脇屋 太一

PURPOSE: There are no reports showing the significance and effective range of dissection for patients with lateral lymph node metastasis (LLNM). This study aimed to investigate the indications for lateral lymph node dissection (LLND) in patients with LLNM based on prognostic factors and recurrence types. METHODS: We reviewed 379 patients with advanced rectal cancer who were treated with total mesorectal excision plus LLND. We analyzed background factors and survival times of patients who had LLNM to determine prognostic factors and recurrence types. RESULTS: Pathological LLNM occurred in 44 (11.6%). Among patients with LLNM, the predictors of poor prognoses, according to univariate analysis, were > 3 node metastases, the presence of node metastasis on both sides, and spreading beyond the internal iliac lymph nodes. Moreover, LLNM beyond the internal iliac region was found to be an independent prognostic risk factor. Twenty-eight of the 44 patients with lateral lymph node metastasis (64%) relapsed, 22 of whom had distant metastases and 11 of whom experienced local recurrences. Among the latter group, nine (20%) and two (5%) had recurrences in the central and lateral pelvis, respectively. CONCLUSION: The therapeutic benefit of resection was high, especially in patients with ≤ 3 positive lateral lymph nodes, one-sided bilateral lymph node areas, and positive nodes localized near the internal iliac artery.

BACKGROUND: Neoadjuvant chemoradiotherapy and total mesorectal excision comprise the standard of care for rectal cancer in multiple guidelines. However, neoadjuvant chemoradiotherapy has not exhibited clear survival benefits, but rather has led to an increase in adverse events. Conversely, neoadjuvant chemotherapy is expected to prevent adverse events caused by radiation, yet this treatment is still controversial. OBJECTIVE: To evaluate the feasibility and efficacy of S-1 and oxaliplatin neoadjuvant chemotherapy together with total mesorectal excision for resectable locally advanced rectal cancer. DESIGN: The study was a prospective, single-arm phase II trial. SETTINGS: The study was conducted at multiple institutions. PATIENTS: Fifty-eight patients with resectable locally advanced rectal cancer were enrolled. INTERVENTION: Three cycles of S-1 and oxaliplatin were administered before surgery. S-1 was administered orally at 80 mg/m2/day for 14 consecutive days, followed by a 7-day resting period. Oxaliplatin was given intravenously on the first day at a dose of 130 mg/m2/day. The duration of one cycle was considered to be 21 days. Total mesorectal excision with bilateral lymph node dissection was carried out after neoadjuvant chemotherapy. MAIN OUTCOME MEASURES: The study was designed to detect the feasibility and efficacy of S-1 and oxaliplatin as neoadjuvant chemotherapy. RESULTS: The completion rate of three courses of S-1 and oxaliplatin as neoadjuvant chemotherapy was 94.8% (55/58). The reasons for discontinuation were thrombocytopenia (3.4%) and liver injury (1.7%). The most common severe (grade ≥ 3) adverse effect of neoadjuvant chemotherapy was thrombocytopenia (3.4%). There were no severe adverse clinical symptoms. Consequently, R0 resection was achieved in 51 of 52 patients (98.1%). Pathological complete response occurred in 10 patients (19.2%). LIMITATIONS: This was a single-arm, nonrandomized phase II study. CONCLUSIONS: The combination of S-1 and oxaliplatin neoadjuvant chemotherapy and total mesorectal excision is a feasible and promising treatment option for resectable locally advanced rectal cancer. See Video Abstract at http://links.lww.com/DCR/B555.

＜文献概要＞ポイント ◆ロボット支援下膵体尾部切除術は操作性の高い鉗子ときわめて質の高い3D画像により,多くの膵腫瘍に対して有益な術式になることが期待される.◆弘前大学方式では,患者の右側に2つおよび左側に1つのロボットアームを配置し,術者は左手で2本および右手で1本の鉗子を操作する.◆ロボット膵体尾部切除術のデメリットは触覚がないことであるが,高度な3D画像による視覚や助手との細かな連携によりデメリットを十分に補うことができる.

2020年4月の診療報酬改定により、膵癌を含める膵腫瘍に対するロボット支援下膵体尾部切除術(robot-assisted distal pancreatectomy:RADP)が保険収載を受けた。ロボット支援下手術では、操作性の高い鉗子と極めて質の高い3D画像により精緻な手術を可能とし、多くの膵腫瘍に対して有益な術式になることが期待される。しかしロボット手術の高い技術の側面には、腹腔鏡下手術では経験されない新たな弱点もある。したがってRADP導入期は、良性もしくは良悪性境界病変を適応とし徐々に適応範囲を広げていくべきと考えられる。本稿では、当施設で行っている良悪性境界病変に対するRADPの実際を紹介するとともに、同手術の安全な導入に関して概説する。(著者抄録)

BACKGROUND: Intra-ampullary papillary-tubular neoplasm (IAPN) has been classified as a Vater papillary tumor. The prognosis of IAPN is generally relatively good. Here, we describe a patient with a mucinous adenocarcinoma cluster in the Vater papilla of IAPN origin. CLINICAL PRESENTATION: The patient was a 66-year-old man who was admitted to our hospital after a diagnosis of pancreatic head carcinoma based on a pancreatic duct dilatation found on abdominal ultrasound. CT showed a 40 mm lesion in the pancreatic head and expansion of the main pancreatic duct to a maximum diameter of 9 mm on the caudal side of the lesion. The extrahepatic bile duct had also expanded to a maximum diameter of 8 mm. PET/CT showed fluorodeoxyglucose (FDG) accumulation of SUVmax 6.02 that corresponded to the tumor in the pancreatic head, though it did not suggest distant metastasis. The patient was diagnosed with pancreatic head carcinoma T3 N0 M0 Stage IIA and underwent a pancreaticoduodenectomy. Pathology indicated that the tumor in the pancreatic head was a benign inflammatory lesion. On the other hand, the papillotubular tumor pervading the lumen in the duodenal papillary common channel met the criteria for IAPN, and a mucinous adenocarcinoma cluster found in the surrounding stroma suggested malignant transformation of IAPN. No metastasis to lymph nodes was demonstrated. With regard to the mucus phenotype of each lesion, the IAPN was MUC2 and MUC5AC positive, while the mucinous adenocarcinoma was MUC2-positive and MUC5AC-negative. In addition, CD10 was negative in both lesions, suggesting that mucus transformation from the gastric type to the intestinal type was a key element. A blood test 10 months after surgery showed increased CA19-9 (105 U/mL) and CEA (7.1 ng/mL). Abdominal CT showed multiple cystoid nodes in the liver, which were diagnosed as multiple liver metastases of mucinous adenocarcinoma transformed from the IAPN. CONCLUSIONS: We reported a case with IAPN that developed in the Vater papilla, which took an extremely malignant course. IAPN generally has a good prognosis, but it is important to understand that a malignant course may occur.

Massive intraoperative blood loss (IBL) negatively influence outcomes after surgery for pancreatic ductal adenocarcinoma (PDAC). However, few data or predictive models are available for the identification of patients with a high risk for massive IBL. This study aimed to build a model for massive IBL prediction using a decision tree algorithm, which is one machine learning method. One hundred and seventy-five patients undergoing curative surgery for resectable PDAC at our facility between January 2007 and October 2020 were allocated to training (n = 128) and testing (n = 47) sets. Using the preoperatively available data of the patients (34 variables), we built a decision tree classification algorithm. Of the 175 patients, massive IBL occurred in 88 patients (50.3%). Binary logistic regression analysis indicated that alanine aminotransferase and distal pancreatectomy were significant predictors of massive IBL occurrence with an overall correct prediction rate of 70.3%. Decision tree analysis automatically selected 14 predictive variables. The best predictor was the surgical procedure. Though massive IBL was not common, the outcome of patients with distal pancreatectomy was secondarily split by glutamyl transpeptidase. Among patients who underwent PD (n = 83), diabetes mellitus (DM) was selected as the variable in the second split. Of the 21 patients with DM, massive IBL occurred in 85.7%. Decision tree sensitivity was 98.5% in the training data set and 100% in the testing data set. Our findings suggested that a decision tree can provide a new potential approach to predict massive IBL in surgery for resectable PDAC.

Pancreatic ductal adenocarcinoma (PDAC) is highly malignant. While cancers in other organs have shown clear improvements in 5-year survival, the 5-year survival rate of pancreatic cancer is approximately 10%. Early relapse and metastasis are not uncommon, making it difficult to achieve an acceptable prognosis even after complete surgical resection of the pancreas. Studies have been performed on various treatments to improve the prognosis of PDAC, and multidisciplinary approaches including non-surgical treatments have led to gradual improvement. In the present literature review, we have described the significance of anatomical and biological resectability criteria, the concept of R0 resection in surgical treatment, the feasibility of minimally invasive surgery, the remarkable development of perioperative chemotherapy, the effectiveness of conversion surgery for unresectable PDAC, and ongoing challenges in PDAC treatment. We also provide an essential update on these subjects by focusing on recent trends and topics.

＜文献概要＞ポイント ◆助手は,体外情報を術者に伝えるとともにロボットアームの衝突回避などの対策をとる.必要に応じてポート位置の調整や追加挿入を行う.◆触覚を有しないアーム鉗子による臓器損傷の回避に術者は最大限の注意を払い,臓器圧迫を伴う術野展開は基本的に助手が行う.◆助手は,完全ロボット手術,ハイブリッド手術の如何にかかわらず,腹腔鏡手術操作に習熟する必要がある.また,腹腔鏡下手術ならびに開腹手術へのconversionに対応する必要がある.

BACKGROUND AND OBJECTIVE: Tacrolimus clearance (CL) is significantly altered according to recovery of liver function at an early stage after living donor liver transplantation (LDLT). In this study, we aimed to examine the impact of the change rate from postoperative day (POD) 1 in CL (ΔCL) of tacrolimus during continuous intravenous infusion (CIVI) on recipient recovery. METHODS: A tacrolimus population pharmacokinetic model on POD1 after LDLT was developed using Phoenix NLME 1.3. The CLPOD1 was calculated using the final model. The CLPOD4-7 was calculated by dividing total daily tacrolimus dose by the area under the concentration-time curve from 0 to 24 h. RESULTS: Data were obtained from 57 LDLT recipients, along with 540 points (177 points on POD1, 363 points on POD4-7) of tacrolimus whole blood concentrations at CIVI. The median tacrolimus CL decreased from POD1 to POD4 (from 2.73 to 1.40 L/h) and was then stable until POD7. Stepwise Cox proportional hazards regression analyses showed that the graft volume (GV)/standard liver volume (SLV) ratio (GV/SLV) and the tacrolimus ΔCLPOD6 were independent factors predicting early discharge (within 64 days median value) of recipients after LDLT [hazard ratio (HR) = 1.041, P = 0.001 and HR = 1.023, P = 0.004]. CONCLUSIONS: The tacrolimus ΔCL during CIVI immediately after LDLT in each recipient was a useful indicator for evaluation of recovery at an early stage after LDLT.