天野 雄介

The present study immunohistochemically investigated trimethylation of lysine 27 of histone 3 (H3K27me3) expression in 769 endometrial carcinomas and 196 uterine mesenchymal tumors. One dedifferentiated endometrial carcinoma (DEC) and one carcinosarcoma showed H3K27me3 deficiency that was limited to undifferentiated and sarcomatous components, respectively. Switch/sucrose nonfermenting (SWI/SNF) complex subunits (SMARCA4, SMARCB1, and ARID1A/1B) and mismatch repair proteins were proficient in both tumors. The dimethylation of H3K27 (H3K27me2) was deficient in the undifferentiated component, whereas the sarcomatous component had scattered H3K27me2-positive cells. CXorf67, which inhibits PRC2 function, was diffusely expressed in the sarcomatous component. CXorf67 was negative in the undifferentiated component, which was submitted to a genetic analysis and showed no alterations in PRC2 core subunits or H3K27. The present results suggest H3K27 methylation dysregulation as a cause of SWI/SNF-proficient DEC and carcinosarcoma and imply differences in their level of and the mechanisms underlying H3K27 methylation dysregulation.

We previously proposed the classification of lung adenocarcinoma into two groups: the bronchial epithelial phenotype (BE phenotype) with high-level expressions of bronchial epithelial markers and actionable genetic abnormalities of tyrosine kinase receptors and the non-BE phenotype with low-level expressions of bronchial Bronchial epithelial (BE) epithelial markers and no actionable genetic abnormalities of tyrosine kinase receptors. Here, we performed a comprehensive analysis of tumor morphologies in 3D cultures and xenografts across a panel of lung cancer cell lines. First, we demonstrated that 40 lung cancer cell lines (23 BE and 17 non-BE) can be classified into three groups based on morphologies in 3D cultures on Matrigel: round (n = 31), stellate (n = 5), and grape-like (n = 4). The latter two morphologies were significantly frequent in the non-BE phenotype (1/23 BE, 8/17 non-BE, p = 0.0014), and the stellate morphology was only found in the non-BE phenotype. SMARCA4 mutations were significantly frequent in stellate-shaped cells (4/4 stellate, 4/34 non-stellate, p = 0.0001). Next, from the 40 cell lines, we successfully established 28 xenograft tumors (18 BE and 10 non-BE) in NOD/SCID mice and classified histological patterns of the xenograft tumors into three groups: solid (n = 20), small nests in desmoplasia (n = 4), and acinar/papillary (n = 4). The latter two patterns were characteristically found in the BE phenotype. The non-BE phenotype exhibited a solid pattern with significantly less content of alpha-SMA-positive fibroblasts (p = 0.0004) and collagen (p = 0.0006) than the BE phenotype. Thus, the morphology of the tumors in 3D cultures and xenografts, including stroma genesis, reflects the intrinsic properties of the cancer cell lines. Furthermore, this study serves as an excellent resource for lung adenocarcinoma cell lines, with clinically relevant information on molecular and morphological characteristics and drug sensitivity.

The clinical signs of cervico-isthmic pregnancy during pregnancy remain unknown. We herein report a case of cervico-isthmic pregnancy showing placental insertion into the cervix with cervical shortening, with a final diagnosis of placenta increta at the uterine body and cervix. A 33-year-old multiparous woman with a history of cesarean section was referred to our hospital at 7 weeks of gestation with suspected cesarean scar pregnancy. Cervical shortening with a cervical length of 14 mm was noted at 13 weeks of gestation. The placenta is gradually inserted into the cervix. An ultrasonographic examination and magnetic resonance imaging strongly suggested placenta accreta. We planned elective cesarean hysterectomy at 34 weeks of gestation. The pathological diagnosis was cervico-isthmic pregnancy with placenta increta at the uterine body and cervix. In conclusion, placental insertion into the cervix with cervical shortening in the early pregnancy period may be a clinical sign to suspect cervico-isthmic pregnancy.

This report presents a case of malignant melanoma in a 40-year-old male who underwent resection of the tumor in his right ankle. Eleven months after the resection, a subcutaneous mass was observed on his right femur. Ultrasound examination revealed a hypoechoic tubular structure in the right thigh, with a small amount of blood flow in the lesion. Using ultrasound and fine-needle aspiration, the patient was diagnosed with metastasis and lymphovascular invasion of malignant melanoma. Treatment with an immune checkpoint inhibitor was originally scheduled, but the lesion disappeared spontaneously after the fine-needle aspiration.

AIMS: The pathological diagnosis of undifferentiated and dedifferentiated endometrial carcinomas (UC/DCs) is prognostically important. However, undifferentiated components may be confused with other subtypes, particularly grade 3 endometrioid carcinomas (G3ECs). ZEB1 has recently been identified as a promising marker because it is frequently expressed in the undifferentiated components of UC/DCs, but not in other carcinomas. Therefore, we herein evaluated the diagnostic utility of ZEB1 with an emphasis on distinguishing between UC/DCs and G3ECs using an expanded cohort of endometrial carcinomas and carcinosarcomas. METHODS AND RESULTS: Immunostaining for ZEB1 was performed on whole-tissue sections of 19 UC/DCs, 194 non-UC/DC endometrial carcinomas, and 29 carcinosarcomas. Staining was defined as negative (<5%), focal (5-50%), and diffuse expression (>50%). ZEB1 was expressed in 84% of the undifferentiated components of UC/DCs (diffuse in 14, focal in two). Focal expression was observed in eight non-UC/DC endometrial carcinomas and diffuse expression in seven, with the latter comprising G3ECs (4/76), serous carcinoma (1/37), clear cell carcinoma (1/21), and neuroendocrine carcinoma (1/3). Epithelial differentiation was morphologically and immunohistochemically less evident in G3ECs and neuroendocrine carcinoma with diffuse ZEB1 expression. All carcinosarcomas showed diffuse ZEB1 expression in their sarcomatous components. CONCLUSION: Immunostaining for ZEB1 was sufficiently sensitive to detect undifferentiated components. Diffuse ZEB1 expression showed high specificity for distinguishing between undifferentiated components and G3ECs; however, ZEB1 expression was not entirely specific to UC/DCs. The integration of ZEB1 into the diagnosis of UC/DCs requires careful examinations to exclude other tumours, such as less differentiated G3ECs, neuroendocrine carcinomas, and carcinosarcomas.

INTRODUCTION AND IMPORTANCE: Intussusception is invagination of the bowel and is rare in adults, representing only 5% of all cases of intussusception. Duodenal intussusception is also very rare. To the best of our knowledge, there is only one previous report of a malignant tumor in the fourth portion of the duodenum as the lead point of intussusception (Vaibhav et al., 2021 [1]). This reports a duodenal-duodenal intussusception caused by a malignant tumor in the third portion of the duodenum. CASE PRESENTATION: A 36-year-old woman with abdominal pain was diagnosed with duodenal intussusception by abdominal ultrasonography and computed tomography scan. Double balloon endoscopy showed that the intussusception had spontaneously reduced, and a tumor was found in the third portion of the duodenum. Open resection was performed because of the tumor location. Pathologic examination revealed adenocarcinoma with an adenoma of the duodenum. The patient had no evidence of recurrence for 4 years after resection. CLINICAL DISCUSSION: This patient had a primary duodenal malignancy and presented with intussusception, Duodenal intussusception is a rare condition requiring prompt intervention, usually requiring surgery. In this patient, since endoscopic resection was difficult, partial resection of duodenum was performed by open surgery assisted by double balloon enteroscopy. The pathological diagnosis of the resected specimen was primary duodenal malignancy. CONCLUSION: This is a report of adult duodenal intussusception caused by a primary duodenal malignancy. This rare condition posed an intriguing challenge for the optimal operative approach.

SMARCA4-deficient uterine sarcoma (SMARCA4-DUS) was recently proposed as a new entity of uterine sarcoma. Reported cases of SMARCA4-DUS showed the loss of SMARCA4 and SMARCA2 expression. However, the prevalence of their deficiency in uterine mesenchymal tumors remains unclear. This study immunohistochemically examined the expression of SMARCA4, SMARCA2, and SMARCB1 in 206 uterine mesenchymal tumors and detected a round cell tumor with the loss of SMARCA4 and SMARCA2 and a low-grade endometrial stromal sarcoma with SMARCA4 deficiency. The remaining 204 cases, including 170 smooth muscle tumors, 22 endometrial stomal nodule/sarcomas, seven undifferentiated uterine sarcomas, two adenosarcomas, one uterine tumor resembling ovarian sex cord tumor, and two perivascular epithelioid cell tumors, retained the expression of both SMARCA4 and SMARCA2. All tumors retained SMARCB1 expression. The round cell tumor with the loss of SMARCA4 and SMARCA2 was composed of diffuse small round cell growth with follicle-like spaces, which resembled small cell carcinoma of the ovary, hypercalcemic type. Immunohistochemically, the tumor showed the proficient expression of mismatch repair proteins and wild-type p53 expression, which favored SMARCA4-DUS; however, the tumor harbored the PIK3CA mutation, and thus, was reclassified as undifferentiated endometrial carcinoma. In conclusion, SMARCA4, SMARCA2, and SMARCB1 were rarely deficient in uterine mesenchymal tumors. SMARCA4 immunohistochemistry has potential in the diagnosis of SMARCA4-DUS with the exclusion of some tumors showing its deficiency, such as endometrial stromal sarcoma and undifferentiated carcinoma. Undifferentiated carcinoma may show an indistinguishable morphology and immunophenotype from SMARCA4-DUS, and thus, molecular analysis is required for their distinction in diagnostic practice.

Switch/sucrose nonfermenting complex subunits, such as BRG1, INI1, and ARID1B, are inactivated in a subset of endometrial undifferentiated carcinoma and dedifferentiated carcinoma (DC). Limited information is currently available on their prevalence in other subtypes or the nosological status of endometrial carcinoma with their deficiencies. This study immunohistochemically examined the expression status of BRG1, INI1, and ARID1B using 570 archived cases of endometrial carcinoma and carcinosarcoma resected at a single institution. We identified 1 BRG1-deficient undifferentiated carcinoma, 8 BRG1/INI1/ARID1B-deficient DC, and 3 BRG1-deficient clear-cell carcinomas. None of the cases of endometrioid and serous carcinomas or carcinosarcoma showed deficiencies of these subunits. We then compared 8 BRG1/INI1/ARID1B-deficient DC with 6 BRG1/INI1/ARID1B-intact DC and 28 carcinosarcomas, the latter of which was often confused with DC. Histologically, BRG1/INI1/ARID1B-intact and BRG1/INI1/ARID1B-deficient DC shared a monotonous solid appearance with rhabdoid and epithelioid cells and a myxoid stroma; however, abrupt keratinization and cell spindling was absent in BRG1/INI1/ARID1B-deficient tumors. The median overall survival of patients with BRG1/INI1/ARID1B-deficient DC was 3.8 months, which was worse than those with BRG1/INI1/ARID1B-intact DC (P=0.008) and with carcinosarcoma (P=0.004). BRG1/INI1/ARID1B-deficient DC may be a separate entity with an aggressive behavior to be distinguished from BRG1/INI1/ARID1B-intact DC and carcinosarcoma. Regarding clear-cell carcinoma (n=12), BRG1 deficiency appeared to be mutually exclusive with abnormal ARID1A, BRM, and p53 expression. Further studies are needed to clarify whether BRG1 deficiency plays a role in the pathogenesis of clear-cell carcinoma.

We herein report a variant case of desmoplastic small round cell tumor (DSRCT) showing limited desmoplasia and confusing immunohistochemical findings. A 26-year-old male was referred for multiple abdominal masses. Laparoscopic biopsy showed only the solid proliferation of small round cells, and he was initially diagnosed with small cell carcinoma. At autopsy, the tumor spread diffusely throughout the abdominal and pelvic cavities. Although the tumor was composed of a predominantly solid pattern of small round cells, multiple samples revealed a fibrous stroma in limited areas only. While immunohistochemistry showed the diffuse expression of desmin, CD99, and bcl-2, epithelial differentiation was unclear with few cytokeratin-positive cells and no staining for the epithelial membrane antigen. Although fluorescence in situ hybridization analysis indicated the EWSR1 gene rearrangement, we were unable to exclude Ewing sarcoma considering the morphological and immunohistochemical findings. The diagnosis of DSRCT was confirmed with a reverse transcription-polymerase chain reaction for EWSR1-WT1 fusion transcripts. DSRCT must be included in a differential diagnosis of small round cell tumors even if desmoplasia is not immediately detected, and thorough sampling and a molecular analysis are mandatory.

Molecular targeted therapies against EGFR and ALK have improved the quality of life of lung adenocarcinoma patients. However, targetable driver mutations are mainly found in thyroid transcription factor-1 (TTF-1)/NK2 homeobox 1 (NKX2-1)-positive terminal respiratory unit (TRU) types and rarely in non-TRU types. To elucidate the molecular characteristics of the major subtypes of non-TRU-type adenocarcinomas, we analyzed 19 lung adenocarcinoma cell lines (11 TRU types and 8 non-TRU types). A characteristic of non-TRU-type cell lines was the strong expression of TFF-1 (trefoil factor-1), a gastric mucosal protective factor. An immunohistochemical analysis of 238 primary lung adenocarcinomas resected at Jichi Medical University Hospital revealed that TFF-1 was positive in 31 cases (13%). Expression of TFF-1 was frequently detected in invasive mucinous (14/15, 93%), enteric (2/2, 100%), and colloid (1/1, 100%) adenocarcinomas, less frequent in acinar (5/24, 21%), papillary (7/120, 6%), and solid (2/43, 5%) adenocarcinomas, and negative in micropapillary (0/1, 0%), lepidic (0/23, 0%), and microinvasive adenocarcinomas or adenocarcinoma in situ (0/9, 0%). Expression of TFF-1 correlated with the expression of HNF4-α and MUC5AC (P < .0001, P < .0001, respectively) and inversely correlated with that of TTF-1/NKX2-1 (P < .0001). These results indicate that TFF-1 is characteristically expressed in non-TRU-type adenocarcinomas with gastrointestinal features. The TFF-1-positive cases harbored KRAS mutations at a high frequency, but no EGFR or ALK mutations. Expression of TFF-1 correlated with tumor spread through air spaces, and a poor prognosis in advanced stages. Moreover, the knockdown of TFF-1 inhibited cell proliferation and soft-agar colony formation and induced apoptosis in a TFF-1-high and KRAS-mutated lung adenocarcinoma cell line. These results indicate that TFF-1 is not only a biomarker, but also a potential molecular target for non-TRU-type lung adenocarcinomas.

症例は45歳の男性で,多発血管炎性肉芽腫症に対して当院アレルギー・リウマチ科で薬剤療法を開始した.開始後12日目に下腹部痛が出現し,腹部CTにて消化管穿孔と診断し緊急手術を施行した.小腸間膜対側に10mm以下の発赤を20ヶ所認め,うち2ヶ所の穿孔部を含む3ヶ所を部分切除した.術後経過は良好で,9日目に薬剤療法を再開した小腸穿孔部の病理組織学的検査所見では,血管壁への炎症細胞の浸潤を認め,多発血管炎性肉芽腫症に伴う消化管穿孔と診断した.術後53日目に絞扼性イレウスが疑われ緊急手術を施行したが,明らかな絞扼性イレウスや穿孔の所見は認めなかった.その後の経過は良好で,薬剤療法を再開,継続中である.今回の検討から多発血管炎性肉芽腫症に伴う消化管穿孔は重症化しやすく,潰瘍性病変が多発する傾向にあり,ときに再穿孔を来すことがわかった.これらを十分理解し,患者・家族へ説明し,治療にあたることが必要である.(著者抄録)

症例は60歳代女性で、2週間程度で亜急性進行性の多発脳神経障害と錐体路・小脳・全感覚路の障害を認めた。頭部MRI所見より中枢神経系原発悪性リンパ腫(PCNSL)と考えられたが、脳幹部位であったため生検による組織診断が不可能で、脳脊髄液細胞診においても確定には至らなかった。ステロイド治療により病変の縮小と造影効果の消失を認めたが、約半年後に症状の急速な悪化がみられた。MRIで病変の広がりを認め、鎖骨上窩や腹腔内リンパ節の腫大、右腎周囲・脾・膵・腸管周囲の腫瘤、胸腹水貯留がみられ、再発/浸潤が疑われた。その後の治療で寛解になっている。当院の過去10年間において脳生検または手術を施行したPCNSLは34例で、全脳腫瘍に対して4.9%と少なく、全例においてDLBCLであった。さらに脳脊髄液細胞診を行い、悪性リンパ腫が疑われた症例は2例であった。脳生検または手術を施行しなかったPCNSLの症例は今回の症例のみで、他臓器転移があった症例は他に1例みられた。

当院では開院当初(1974年)からの旧病理解剖室と2016年にリニューアル移転した現在の新病理解剖室において、ホルマリン濃度が0.1ppm以下の第1管理区分を目標とした環境改善対策を旧剖検室で1回、新剖検室で3回、合わせて4回実施した。本稿では、対策前後の作業環境改善結果について報告した。当院の旧剖検室はホルマリン環境対策を一切行っていなかった。旧倉庫は病理レポートの保管棚と同じスペースにあり、切り出し台、ホルマリン原液ストック場と床に直置きした臓器保管用ホルマリンバケツ置き場が混在していた。2013年に旧解剖室と旧倉庫のホルマリン対策を初めて行い、それを参考に2016年に新解剖室・臓器保管倉庫のリニューアルが実施され、1階の旧剖検室から地下1階の新剖検室に場所を移した。リニューアル移転時のホルマリン環境測定結果は、第1管理区分に至らなかった。新解剖室では切り出し臓器時にホルマリン吸収シートを使用したり、新倉庫で保管容器のビニール袋使用による二重密閉・パッキン付き容器への変更・ホルマリン吸着ビーズを使用したりと工夫を重ね、最終的には何とか第1管理区分を達成できた。旧剖検室では、ホルマリン臭がするのが当たり前との意識で剖検業務をこなしていた。現在の新剖検室は旧剖検室に比べてホルマリン臭はかなり軽減されてはいる。しかし現在第1管理区分を達成していても、ホルマリン臭がきつくなる場面も多々あり、ホルマリン濃度の低減への根本的な解決にはなっていないと思われる。

Data presented in this article are related to our article entitled "Unilateral posterior reversible encephalopathy syndrome: A case report" [1]. Cases of Posterior Reversible Encephalopathy Syndrome (PRES) involving unilateral lesions are very rare. We searched the PubMed database using keywords such as PRES, unilateral, and asymmetric and found a small number of cases to include in our review. We summarized the characteristics of these reported cases of unilateral PRES, including our case.

Atypical polypoid adenomyoma (APA) is a polypoid lesion that is comprised of atypical endometrial glands and fibromuscular stroma, which pathologists often confuse with myoinvasive endometrioid carcinoma. Here, we characterized the immunohistochemical and molecular features of the stromal components of APA to find distinct markers between APA and myoinvasive endometrioid carcinoma. First, we examined the immunohistochemical expression and gene mutations that were previously investigated in uterine and breast fibroepithelial lesions using 12 cases of APA. α-smooth muscle actin was diffusely positive in the stromal component in all cases, whereas desmin and h-caldesmon were focally expressed in 8 cases. Positive expression was also observed in 9 cases for CD10, 12 cases for estrogen receptor, 3 cases for HMGA2, and 3 cases for MDM2. All cases showed normal p53 expression and negative staining of HMGA1 and nuclear β-catenin. No mutations in MED12 exon 2 and the TERT promoter were found in any cases. p16 was positive in all cases and showed diffuse expression in 10 cases. We assessed stromal p16 expression in 84 cases of myoinvasive endometrioid carcinoma. The stromal p16 status was negative in all myoinvasive carcinomas, but there was 1 case with focal staining. There was a significant difference in stromal p16 expression between APA and myoinvasive endometrioid carcinoma (P<0.001). Stromal p16 expression was more suggestive of APA than myoinvasive endometrioid carcinoma among endometrial fibroepithelial lesions.

BACKGROUND: Pegylated liposomal doxorubicin plays an important role in the treatment of patients with severe refractory human immunodeficiency virus (HIV)-associated Kaposi sarcoma (KS). High cumulative doses of conventional doxorubicin exceeding 500 mg/m2 are known to cause cardiac toxicity. However, the safe cumulative dose of pegylated liposomal doxorubicin is unclear. CASE PRESENTATION: A 40-year-old Japanese man with HIV infection presented with pain, edema, and multiple skin nodules on both legs which worsened over several months. He was diagnosed with HIV-associated KS. He received long-term pegylated liposomal doxorubicin combined with antiretroviral therapy for advanced, progressive KS. The cumulative dose of pegylated liposomal doxorubicin reached 980 mg/m2. The patient's left ventricular ejection fraction remained unchanged from baseline during treatment. After he died as a result of cachexia and wasting, caused by recurrent sepsis and advanced KS, an autopsy specimen of his heart revealed little or no evidence of histological cardiac damage. We also conducted a literature review focusing on histological changes of the myocardium in patients treated with a cumulative dose of pegylated liposomal doxorubicin exceeding 500 mg/m2. CONCLUSIONS: This case report and literature review suggest that high (> 500 mg/m2) cumulative doses of pegylated liposomal doxorubicin may be used without significant histological/clinical cardiac toxicity in patients with HIV-associated KS.

Decreased cell adhesion has been reported as a significant negative prognostic factor of lung cancer. However, the molecular mechanisms responsible for the cell incohesiveness in lung cancer have not yet been elucidated in detail. We herein describe a rare histological variant of lung adenocarcinoma consisting almost entirely of individual cancer cells spreading in alveolar spaces in an incohesive pattern. A whole exome analysis of this case showed no genomic abnormalities in CDH1 or other genes encoding cell adhesion molecules. However, whole mRNA sequencing revealed that this case had an extremely high expression level of mucin 21 (MUC21), a mucin molecule that was previously shown to inhibit cell-cell and cell-matrix adhesion. The strong membranous expression of MUC21 was found on cancer cells using mAbs recognizing different O-glycosylated forms of MUC21. An immunohistochemical analysis of an unselected series of lung adenocarcinoma confirmed that the strong membranous expression of MUC21 correlated with incohesiveness. Thus, MUC21 could be a promising biomarker with potential diagnostic and therapeutic applications for lung adenocarcinoma showing cell incohesiveness.

35歳女性。発赤と疼痛を伴う左乳房腫瘤を主訴に近医を受診、左乳腺炎として抗菌薬CFPN-PI(Cefcapene pivoxil)を投与されるも改善せず、当科へ紹介となった。乳房超音波では左乳房AC領域にプローブのスケールを超える境界不明瞭な低エコー腫瘤がみられ、内部は不均一で一部嚢胞様構造を呈していた。また、乳房MRIではダイナミック造影で左乳房AC領域を中心に最大径95mmの造影効果を伴う腫瘤を認め、内部には複数のリング状濃染される結節性病変を認めた。以上、これらの所見のほか、乳房膿様分泌液からの細菌培養により、本症例はCorynebacterium属感染による巨大肉芽腫性乳腺炎を考え、抗菌薬であるLVFXの内服とドレナージによる感染コントロールを行い、次いで少量のステロイド内服を開始したところ、左乳房腫瘤は徐々に蝕知されなくなり、治癒が得られた。

BACKGROUND: Osteosarcomas of the head and neck region are rare entities that comprise < 10% of all osteosarcomas. Multimodality treatment of patients with osteosarcoma is well-established for osteosarcoma in long bones, and the benefits of chemotherapy in long bones are clearly known. However, there is no consensus regarding the effects of chemotherapy in cases of head and neck osteosarcoma. The prognostic factor for head and neck osteosarcoma is complete tumor resection with negative margin, which is a radical surgery. However, a clear margin may be difficult to achieve in the head and neck region. CASE PRESENTATION: We present a case of a 69-year-old Japanese woman who developed osteosarcoma of the condyle within the masticator space and infratemporal fossa, which was treated with radical surgery using a modified preauricular and transmandibular approach. Although we recommended adjuvant treatment after surgery, the patient refused this treatment. There was no evidence of local recurrence or distant metastasis through 30 months of follow-up. CONCLUSIONS: Our modified preauricular and transmandibular approach allowed access to the masticator space and infratemporal fossa, thereby increasing complete resection of the tumor and resulting in minimal functional and cosmetic deficits.

RATIONALE: Liver heterotopia associated with congenital diaphragmatic hernia (CDH) is a rare condition; to the best of our knowledge, only 17 cases have been reported to date. The histogenesis and clinicopathological features are largely unknown. We herein report 2 cases of liver heterotopia associated with CDH along with 17 cases described in the literature to shed light on their clinicopathological characteristics. PATIENT CONCERNS: Case 1 was a vaginally delivered male newborn who presented with respiratory distress immediately after birth. Case 2 was a female fetus who was found to have left-sided CDH during gestation. DIAGNOSIS: In case 1, a chest X-ray revealed left-sided CDH. In case 2, magnetic resonance imaging performed at 33 weeks of gestation revealed left-sided CDH. INTERVENTIONS: Case 1 underwent diaphragmatic patch repair surgery 3 days after birth. Histopathological examination following surgery in case 1 revealed the presence of ectopic liver tissue in the hernia sac. Case 2 was delivered by Cesarean section, and diaphragmatic patch surgery was performed 3 days after birth. During surgery, an isolated nodule was identified on the peritoneal side of the border of the defective foramen of the diaphragm. Histopathological examination following surgery in case 2 confirmed the presence of an epidermal cyst in the hernia sac. In addition, the isolated nodule was histopathologically found to be ectopic liver tissue. OUTCOMES: In Case 1, CDH recurred at 6 months after surgery, and a second patch repair surgery was performed. The surgically removed hernia sac was found to contain microscopic ectopic liver tissue on histopathology. Case 1 recovered well after surgery, and there was no critical change during the 10-month postoperative period. Case 2 recovered well after surgery, and there was no critical change during the 20-month postoperative period. LESSONS: There were no secondary pathological conditions associated with the presence of ectopic liver in CDH, such as torsion, infarction, rupture, intra-abdominal bleeding, or tumorization. Our observations suggest that liver heterotopia is a rare but asymptomatic condition in patients with CDH.

The major driver mutations of lung cancer, EGFR mutations and EML4-ALK fusion, are mainly detected in terminal respiratory unit (TRU)-type lung adenocarcinomas, which typically show lepidic and/or papillary patterns, but are rarely associated with a solid or invasive mucinous morphology. In order to elucidate the key genetic events in non-TRU-type lung cancer, we carried out whole-exome sequencing on 43 non-TRU-type lung adenocarcinomas based on morphology (17 acinar, nine solid, and two enteric adenocarcinomas, and 15 adenocarcinomas with a mucinous morphology). Our analysis identified mutations in TP53 (16/43, 37.2%), KRAS (13/43, 30.2%), and NKX2-1/TTF-1 (7/43; 16.3%) as the top three significantly mutated genes, while the EGFR mutation was rare (1/43, 2.3%) in this cohort. Eight NKX2-1/TTF-1 mutations (five frameshift, two nonsense, and one missense) were identified, with one case harboring two distinct NKX2-1/TTF-1 mutations (one missense and one frameshift). Functional assays with the NK2 homeobox 1 (NKX2-1)/thyroid transcription factor 1 (TTF-1) mutants revealed that none of them retain the activity as a transcriptional factor. Histologically, invasive mucinous adenocarcinomas accounted for most of the NKX2-1/TTF-1 mutations (five cases), as well as one enteric and one acinar adenocarcinoma. Immunohistochemistry showed that the cohort was largely divided into TTF-1-postive/hepatocyte nuclear factor 4-α (HNF4-α)-negative and TTF-1-negative/HNF4-α-positive groups. NKX2-1/TTF-1 mutations were exclusively found in the latter, in which the gastrointestinal markers, mucin 5AC and cytokeratin 20, were frequently expressed. Bisulfite sequencing revealed that the NKX2-1/TTF-1 gene body was highly methylated in NKX2-1/TTF-1-negative cases, including those without the NKX2-1/TTF-1 mutations. The genetic or epigenetic inactivation of NKX2-1/TTF-1 may play an essential role in the development and aberrant differentiation of non-TRU-type lung adenocarcinomas.

A 68-year-old man presented with polyarthritis, proximal muscle weakness, and erythema of the face, arms, neck, and anterior chest that resembled the V-neck sign. Initially, dermatomyositis (DM) was considered because of the erythema, polyarthritis, and muscle weakness. He also had mediastinal and hilar lymphadenopathy on contrast-enhanced computed tomography. Unexpectedly, a biopsy of the forehead skin revealed numerous multinucleated giant cells. A biopsy of a solitary nodule on the dorsum of his right middle finger revealed similar multinucleated giant cells with ground-glass cytoplasm, leading to the diagnosis of multicentric reticulohistiocytosis (MRH). Although MRH is rare, it should be remembered that MRH can mimic DM.

Decreased cell-substratum adhesion is crucially involved in metastasis. Previous studies demonstrated that lung cancer with floating cell clusters in histology is more likely to develop metastasis. In the present study, we investigated whether cancer cells in long-term, three-dimensional low attachment cultures acquire high metastatic potential; these cells were then used to examine the mechanisms underlying metastasis. Two KRAS-mutated adenocarcinoma cell lines (A549 and H441) were cultured and selected on ultra-low attachment culture dishes, and the resulting cells were defined as FL (for floating) sublines. Cancer cells were inoculated into NOD/SCID mice via an intracardiac injection, and metastasis was evaluated using luciferase-based imaging and histopathology. In vitro cell growth (in attachment or suspension cultures), migration, and invasion were assayed. A whole genomic analysis was performed to identify key molecular alterations in FL sublines. Upon detachment on low-binding dishes, parental cells initially formed rounded spheroids with limited growth activity. However, over time in cultures, cells gradually formed smaller spheroids that grew slowly, and, after 3-4 months, we obtained FL sublines that regained prominent growth potential in suspension cultures. On ordinary dishes, FL cells reattached and exhibited a more spindle-shaped morphology than parental cells. No marked differences were observed in cell growth with attachment, migration, or invasion between FL sublines and parental cell lines; however, FL cells exhibited markedly increased growth potential under suspended conditions in vitro and stronger metastatic abilities in vivo. A genomic analysis identified epithelial-mesenchymal transition (EMT) and c-Myc amplification in A549-FL and H441-FL cells, respectively, as candidate mechanisms for metastasis. The growth potential of FL cells was markedly inhibited by lentiviral ZEB1 knockdown in A549-FL cells and by the inhibition of c-Myc through lentiviral knockdown or the pharmacological inhibitor JQ1 in H441-FL cells. Long-term three-dimensional low attachment cultures may become a useful method for investigating the mechanisms underlying metastasis mediated by decreased cell-substratum adhesion.

Co-expression of MYC and BCL2 proteins in diffuse large B-cell lymphoma (DLBCL), or 'double-expressor lymphoma' (DEL), results in poor patient prognosis, but the significance of DEL when aggressive treatments are applied remains uncertain. We performed a retrospective analysis of 40 patients with de novo DLBCL, who were categorized as being at high/high-intermediate risk according to the age-adjusted International Prognostic Index. Patients underwent an R-Double-CHOP regimen, a dose-intensified immunochemotherapy with or without consolidative high-dose chemotherapy followed by autologous stem cell transplantation. According to immunohistochemical analysis, 10 (25%) patients were categorized as having DEL, showing positivity for MYC (≥40%) and BCL2 (≥50%). The 3 year progression-free survival and overall survival of the DEL group were significantly worse compared with those of the non-DEL group (30% vs. 63%, p = 0.019 and 40% vs. 82%, p = 0.006, respectively). These results suggest that advanced DEL may need discrete treatment strategies.

Undifferentiated (anaplastic) carcinoma with rhabdoid features is a rare and aggressive subtype of pancreatic carcinoma. Here, we report the clinical, histological, and immunohistochemical phenotypes in six autopsy cases of anaplastic carcinoma with rhabdoid features. The patients ranged between 44 and 76 years of age (median, 61 years) and consisted of four males and two females. All patients except one case died within 3 months of diagnosis, as these tumors were found at an advanced stage and were chemoresistant. At autopsy, tumor masses measuring 4-22 cm in maximum diameter were mainly located in the pancreatic body and tail. Microscopically, all cases showed anaplastic carcinoma with rhabdoid features that were discohesive with round to polygonal eosinophilic cytoplasm with occasional inclusions, and that had vesicular nuclei, and prominent nucleoli. Immunohistochemistry showed that the rhabdoid cells, particularly the inclusions, were strongly positive for pan-cytokeratin (AE1/AE3) and vimentin. Meanwhile, downregulation or aberrant cytoplasmic localization with focal aggregation of E-cadherin, β-catenin, and EMA were frequently observed in the rhabdoid cells. Moreover, the intracytoplasmic inclusions were labeled with selective autophagy-related molecules including p62/SQSTM1, ubiquitin, and kelch-like ECH-associated protein 1 (KEAP1). In addition, nuclear factor erythroid 2-related factor 2 (NRF2) and overexpression of its target molecule multidrug resistance-associated protein 1 (MRP1) were commonly observed in the rhabdoid cells. Therefore, these results suggest that p62-mediated aggregation of ubiquitinated intermediate filaments and membranous proteins is an important phenomenon in the rhabdoid phenotype. Indeed, the ubiquitinated aggregates of p62 and KEAP1 would induce activation of NRF2 and upregulation of MRP1, leading to potential chemoresistance of anaplastic carcinoma with rhabdoid features.

Stem cell-based therapy has been proposed as a promising strategy for regenerating tissues lost through incurable diseases. Side population (SP) cells have been identified as putative stem cells in various organs. To examine therapeutic potential of SP cells in hypofunction of exocrine glands, SP cells isolated from mouse exocrine glands, namely, lacrimal and salivary glands, were transplanted into mice with irradiation-induced hypofunction of the respective glands. The secretions from both glands in the recipient mice were restored within 2 months of transplantation, although the transplanted cells were only sparsely distributed and produced no outgrowths. Consistent with this, most SP cells were shown to be CD31-positive endothelial-like cells. In addition, we clarified that endothelial cell-derived clusterin, a secretory protein, was an essential factor for SP cell-mediated recovery of the hypofunctioning glands because SP cells isolated from salivary glands of clusterin-deficient mice had no therapeutic potential, whereas lentiviral transduction of clusterin restored the hypofunction. In vitro and in vivo studies showed that clusterin had an ability to directly inhibit oxidative stress and oxidative stress-induced cell damage. Thus, endothelial cell-derived clusterin possibly inhibit oxidative stress-induced hypofunction of these glands.

Benzo[a]pyrene (BaP), a polycyclic aromatic hydrocarbon produced by cigarette combustion, is implicated as a causative agent in smoking-related cancer and atherosclerosis. 1,25-Dihydroxyvitamin D3 [1,25(OH)2D3], a potent ligand for the nuclear receptor vitamin D receptor (VDR), has been shown to decrease the risk of osteoporosis, some types of cancer and cardiovascular disease, suggesting an opposing effect of vitamin D3 to cigarette smoking. In this study, we investigated the effects of BaP on the vitamin D3 signaling pathway. BaP effectively enhanced the 1,25(OH)2D3-dependent induction of cytochrome P450 24A1 (CYP24A1) in human monocyte/macrophage-derived THP-1 cells and breast cancer MCF-7 cells. BaP combination was less or not effective on mRNA expression of CD14, arachidonate 5-lipoxygenase, and cathelicidin antimicrobial peptide in THP-1 cells. BaP also increased the expression of CYP24A1 induced by a non-vitamin D VDR ligand, lithocholic acid acetate. Another aryl hydrocarbon receptor (AhR) ligand, 2,3,7,8-tetrachlorodibenzo-p-dioxin, enhanced CYP24A1 expression by 1,25(OH)2D3 in THP-1 cells. Treatment of cells with an AhR antagonist and a protein synthesis inhibitor inhibited the enhancing effect of BaP on CYP24A1 induction, indicating that the effects of BaP are mediated by AhR activation and de novo protein synthesis. BaP pretreatment increased 1,25(OH)2D3-dependent recruitment of VDR and retinoid X receptor to the CYP24A1 promoter. Analysis of 1,25(OH)2D3 metabolism showed that BaP enhanced the hydroxylation of 1,25(OH)2D3 by CYP24A1 in THP-1 cells. Thus, AhR activation by BaP stimulates vitamin D3 catabolism. Modulation of vitamin D signaling by AhR may represent a mechanism underlying cigarette smoking-related diseases.

We report an unusual case of gingival anaplastic large-cell lymphoma (ALCL) that occurred in a 76-year-old Japanese woman who showed marked gingival swelling in both the maxilla and mandible. Although the patient received caries and periodontal therapy at the outpatient clinic of our dental hospital, the gingival swelling remained and she was referred to the oral surgery department, where a biopsy of the gingiva was performed. The specimens showed proliferation of large atypical and amphophilic epithelioid cells beneath the covering epithelium. Immunohistochemical analysis of the proliferating cells revealed positivity for CD30 and T-cell markers, such as CD45RB, as well as CD45RO antibodies, and they were weakly positive for the granzyme B antibody. In contrast, the tumor cells were negative for all B-cell markers as well as for CD3, CD56, S-100 protein, epithelial membrane antigen, and p80(NPM/ALK) antibodies. Based on the clinical and histopathologic features, the lesion was diagnosed as an ALCL in both the upper and the lower gingiva. This is an extremely rare case, in which a specific subtype of T-cell lymphoma appeared in the oral cavity.

ヒト口腔癌細胞株HSC-3を用い,分泌型phospholipase A2(sPLA2)とcyclooxygenase(COX)-2の発現と増殖能およびprostaglandin E2(PGE2)産生を解析し,その意義について検討した.HSC-3におけるsPLA2(-II A,-V,-X),COX-1およびCOX-2の発現をRT-PCRと免疫組織化学で検索した.ついで,HSC-3にsPLA2またはCOX-2特異的inhibitorを加え,細胞増殖をMTT法で,PGE2産生量をELISA法で測定した.RT-PCRによりsPLA2-X,COX-1およびCOX-2のmRNA発現を認めたが,sPLA2-II A,-Vは検出されなかった.免疫組織化学によりsPLA2-X,COX-1およびCOX-2はHSC-3細胞質に陽性を示した.HSC-3の細胞増殖は各inhibitor添加により,濃度依存的,経時的に抑制された.またPGE2産生も,各inhibitor添加により低下した.以上より,口腔扁平上皮癌におけるsPLA2の発現を検討したところ,sPLA2-Xが主要なサブタイプであることを明らかにした.また,sPLA2,COX-2の発現が,口腔扁平上皮癌の細胞増殖およびPGE2産生の調節因子の一つであることを示した.本研究の結果,両酵素の機能制御による口腔癌治療の応用の可能性が示された(著者抄録)

A 54-year-old male presented with the complaint of a painful sore on the left side of his tongue. Our examination found an ulcer 15 x 20 mm in size on the left edge of the tongue, with peripheral indurations. The lesion was diagnosed histopathologically as squamous cell carcinoma (T2N0M0). Consequently, the lesion was surgical removed and radical neck dissection was performed. Four months after the operation, two unusual cyst-like lesions were identified in the parapharyngeal space by CT and MRI. A biopsy specimen revealed recurrent carcinoma with a cyst-like structure. The route of the tumor metastasis into the parapharyngeal space was obscured, but it was speculated that the excessive lymph accumulation was due to a lymphatic occlusion caused by the surgical procedure, proliferation of the metastatic carcinoma, or stagnation and accumulation of tissue fluid caused by parapharyngeal invasion by the recurrent lesion.