RYBP contributes to improved prognosis in colorectal cancer via regulation of cell cycle, apoptosis and oxaliplatin sensitivity.

Ring1 and YY­1 binding protein (RYBP) is a member of the polycomb repressive complex 1 and serves as a transcriptional suppressor via epigenetic modification. RYBP has a tumour­suppressive role in solid tumours, but its function in colorectal cancer (CRC) remains unknown. The present study evaluated the expression of RYBP using immunohistochemistry in 140 cases of primary CRC and 11 patient­matched cases of liver metastases. Using CRC cell lines with different TP53 gene status such as HCT116 (TP53wt/wt), HCT116 (TP53­/­), SW48 and DLD­1 cells, proliferation, cell cycle progression and apoptosis, as well as the effect of RYBP on oxaliplatin sensitivity, were assessed. Clinical data showed that low RYBP expression was significantly associated with risk of distant metastasis and recurrence, and patients with high RYBP expression demonstrated significantly better cancer­specific and disease­free survival. In vitro experiments revealed that RYBP suppressed cell proliferation by inducing cell cycle arrest and apoptosis in TP53 wild­type cells. In addition, endogenous RYBP overexpression enhanced sensitivity to oxaliplatin. Therefore, RYBP may contribute to improved prognosis in CRC by regulating the cell cycle, apoptosis and oxaliplatin sensitivity via the p53­mediated pathway.

[A Case Report of Needle-Tract Implantation on the Thoracic Wall after Radiofrequency Ablation for Hepatocellular Carcinoma Treated with Surgical Resection].

A 71-year-old man with hepatocellular carcinoma(HCC)underwent hepatectomy at another hospital in 200X. In 200X+ 7, +9, and +10, radiofrequency ablation(RFA)was performed for HCC recurrence. In 200X+11, he complained of a mass at the right site of the thoracic wall. After further examination, he was diagnosed with needle-tract implantation after RFA. We performed tumorectomy via a thoracotomy. Twelve months after the operation, he is alive with no recurrence. In case of needle-tract implantation after RFA, it is important to consider the possibility of surgical resection for local control.

[A Case of Locally Recurrent Tumor Resected by Left Hemicolectomy with Left Nephrectomy Six Years after Curative Operation for Sigmoid Colon Cancer].

A 65-year-old woman underwent high anterior resection for sigmoid colon cancer in 2011. The histopathological diagnosis was type 2, 25×27 mm, tub2, SE, N2, ly2, v1, and Stage Ⅲb. Her treatment was completed after 6months of adjuvant chemotherapy with UFT plus UZEL followed by a 5-year follow-up study, without recurrence. However, 6years after the initial operation, a routine chest and abdominal CT scan showed a 24mm local recurrence involving the left urinary tract and bilateral lung lesions. Eight courses of systemic chemotherapy using FOLFOX plus panitumumab regimen was administered immediately. CT scan after chemotherapy showed that all masses were downsized and no new lesions were identified. We resected the recurrent tumor after considering it feasible by left hemicolectomy with left nephrectomy. Histopathological examination of the recurrent tumor revealed adenocarcinoma, consistent with that of the previous primary sigmoid colon cancer. She is currently undergoing systemic chemotherapy using the FOLFOX regimen. There has been no change in the lung lesions and no new lesions have developed. This is a very rare case of recurrence more than 5 years after curative resection of Stage Ⅲ colon cancer. This paper presents the case considering that keeping the patient under surveillance for more than 5 years enabled the disclosure of recurrence without subjective symptoms.

[A Case of Perforative Peritonitis Due to Intestinal Metastasis from Lung Cancer].

We here describe a case of an acute peritonitis due to perforation of a small intestine tumor metastasized from a lung cancer. A 66-year-old man who had undergone a bladder cancer procedure 2 years ago and was hospitalized for the second operation, complained sudden abdominal pain. An enhanced abdominal CTrevealed a small amount of free gas and ascites in the abdominal cavity. On the same day, emergency exploratory surgery was performed with the diagnosis of perforative peritonitis. A laparotomy revealed a jejunal tumor with perforation 40 cm distal from the Treitz ligament. After surgery, the patient confessed that he had got a notice of the recurrence of lung cancer which had been treated 9 years ago. The pathological result indicated the lesion was metastasis from lung cancer. Although small intestinal metastatic tumor from lung cancer is rare, it should be considered when acute abdomen is observed.

[Two Cases of Hepatocellular Carcinoma Skin Metastasis].

Case 1: A7 2-year-old man, during diabetes medical treatment, was introduced at our hospital for liver cancer treatment. He had a subcutaneous mass 4 cm in size in the right precordial region, and subsequently underwent an operation. Histopathological findings indicated subcutaneous metastasis of hepatocellular carcinoma. Case 2: A6 0-year-old man presented with a subcutaneous mass noted in the right shoulder during hepatocellular carcinoma treatment. It was diagnosed as metastasis of the hepatocellular carcinoma to the dermis. Metastasis to the skin of internal organ-related tumors is relatively rare and is reported with approximately a 1.4-6.7%frequency of all dissection cases. Hepatocellular carcinoma is infrequent and it is reported that hypodermal and skin metastasis is 0.3-0.7% in autopsy cases. In addition, metastasis of hepatocellular carcinoma to the skin is a relatively terminal symptom.

[A Case of a Metastatic Liver Tumor from a Thymic Carcinoma Detected During a Cesarean Section].

A 40-year-old pregnant woman who had previously been diagnosed with uterine myoma underwent cesarean section. During the operation, a tumor thought to be uterine myoma was found to be an extrauterine tumor arising from the upper abdomen. After the delivery of the fetus, a staging CT scan was performed, which revealed a huge, 18 cm, hepatic tumor in the left lateral segment, a mediastinal tumor with calcification, and multiple lung nodules. She underwent a left hepatic lobectomy and a wedge resection 8 days after the delivery. The initial pathological diagnosis was moderately differentiated neuroendocrine tumor (NET). However, as a primary hepatic NET is extremely rare, further immunohistochemical staining was performed. The tumor was positive for p63, CD5, c-kit, and bcl-2, indicating a diagnosis of thymic carcinoma with liver and lung metastases.