田中 亨

We report a unique case of a 74-old man, who presented with double cancers, showing metastasis of pancreatic cancer to colon cancer. Histopathological examination after surgery revealed that the patient had ascending colon cancer, which metastasized to the liver (pT4N0M1), as well as pancreatic cancer (pT2N1M1) that metastasized to the most invasive portion of the colon cancer, namely the serosal to subserosal layers. Although the mechanisms for this scenario have yet to be elucidated, we speculate that the metastatic pancreatic carcinoma overtook the stromal microenvironment of the colon cancer. Namely, the cancer microenvironment enriched by cancer-associated fibroblasts, which supported the colon cancer, might be suitable for the invasion and engraftment by pancreatic carcinoma. The similarity of histological appearance might make it difficult to distinguish metastatic pancreatic carcinoma within colon cancer. Furthermore, the metastasis of pancreatic carcinoma in colon carcinoma might be more common, despite it not having been previously reported.

INTRODUCTION: We report a patient with a rapidly progressing recurrence of hepatocellular carcinoma (HCC) with a portal vein tumor thrombus after radiofrequency ablation of the original lesion, then treated with transcatheter arterial infusion. Radical hepatic resection demonstrated a complete pathological response. PRESENTATION OF CASE: A 60-year old male with alcoholic cirrhosis and gastric varices was diagnosed with HCC measuring 12mm in segment 8. He underwent laparoscopic radiofrequency ablation, but recurred three months later. The lesion progressed rapidly and the right portal vein was occluded. He then underwent transcatheter arterial infusion with miriplatin and iodized oil, which was effective in reducing the size of the main lesion and portal vein tumor thrombus. Right anterior sectionectomy was then performed. Pathologically, there were no viable HCC cells in either the main lesion or the portal vein thrombus. He is alive two years and nine months after surgery without recurrence. DISCUSSION: A rapidly progressing HCC recurrence with portal vein tumor thrombus is usually associated with a poor prognosis. No effective treatments have been reported in this situation except hepatic resection. In this patient the tumor was effectively reduced after three courses of transarterial miriplatin and subsequent radical hepatic resection. This is the first report to achieve a complete pathological response for such an aggressive recurrence after initial radiofrequency ablation. CONCLUSION: This strategy may result in long-term survival of patients with rapidly progressing recurrent HCC with portal vein thrombus, and further study is warranted.

BACKGROUND: The endoscopic resection of early gastric cancers (EGC) is a standard technique in Japan and is increasingly used throughout the world. Further experience in the treatment of EGC and a clearer delineation of the factors related to lymph-node metastasis would permit a more accurate assessment of endoscopic resection. METHODS: The study group comprised 1,389 patients with EGC who underwent gastrectomy with lymph-node dissection. We evaluated the relations of lymph-node metastasis to clinicopathological factors. RESULTS: Of the 718 patients with intramucosal carcinomas, 14 (1.9%) had lymph-node metastasis. All cases of lymph-node metastasis were associated with ulceration. No lymph-node metastasis was found in patients with intramucosal carcinomas without ulceration, irrespective of tumor size and histological type. Lymph-node metastasis was present in 14 (4.7%) of the 296 patients who had cancer with a submucosal invasion depth of less than 500 microm (sm1). Significantly increased rates of lymph-node metastasis were associated with undifferentiated types, ulcerated lesions and lymphatic invasion. No lymph-node metastasis was found in patients with differentiated sm1 carcinomas 30 mm or less in diameter without ulceration. Lymph-node metastasis occurred in 29% of the patients who had cancer with a submucosal invasion depth of 500 microm or more (sm2). CONCLUSION: This large series of patients with EGC provides further evidence supporting the expansion of indications for endoscopic treatment, as well as warns against potential risks.