Successful Conversion Surgery Following Chylous Ascites After Nivolumab for Advanced Gastric Cancer.

CASE REPORT: A 75-year-old man who underwent nivolumab as the third-line chemotherapy for advanced gastric cancer had chylous ascites (CA) after the primary tumor shrank remarkably. Total parenteral nutrition and subcutaneous octreotide were initiated, and CA disappeared. Nivolumab was continued for a total of 23 courses. Computed tomography showed lymph node swelling; however, staging laparoscopy showed that peritoneal metastasis had disappeared. Therefore, conversion surgery and distal gastrectomy with D1+ dissection were performed. RESULTS: The pathological diagnosis was type IV, poorly differentiated adenocarcinoma (por2) with signet ring cells, ypT2 (muscularis propria), without lymphatic or venous invasion, and no involvement of the proximal and distal margins. After the operation, no recurrence was observed over 7 months with no adjuvant chemotherapy. CONCLUSION: Nivolumab has the potential to lead to R0 resection for patients with peritoneal carcinomatosis gastric cancer. To our knowledge, this is the first report of successful conversion surgery after nivolumab-related chylous ascites.

Mesenteric venous thrombosis as a rare complication of decompression sickness.

BACKGROUND: Decompression sickness (DCS) induced by extravascular and intravascular gas bubbles during decompression can present with varying manifestations, such as joint pain, numbness, cutaneous symptoms, and cardiopulmonary dysfunction. However, mesenteric venous thrombosis (MVT) is a rare complication of DCS. To the best of our knowledge, only a few cases have been reported, and surgical cases of MVT secondary to DCS have not yet been reported. CASE PRESENTATION: A 59-year-old man who was a fisherman and recreational diver dived to a depth of 100 feet. After diving, he noted abdominal and postcervical pain and visited a community hospital. Computed tomography (CT) revealed a large amount of intravenous gas, so he was diagnosed with DCS. He was then transferred to a previous hospital, where hyperbaric oxygen therapy (HBOT) was performed. HBOT reduced the amount of venous gas, but his abdominal pain worsened, so he was transferred to our hospital. CT showed pneumatosis cystoides intestinalis. Because of the possibility of intestinal necrosis, a laparoscopic examination was performed, which revealed necrosis of the transverse colon. We therefore performed a transverse colon resection. He was discharged 36 days after the surgery and followed an uneventful postoperative course. CONCLUSIONS: DCS is likely to cause MVT. If intestinal necrosis is suspected, a laparoscopic examination may be useful for determining the diagnosis and treatment. MVT should be included as a differential diagnosis of abdominal pain that persists after HBOT.

A case report of successful diagnosis of a pulmonary nodule by a survey of oncogenic mutations; primary lung carcinoma or pulmonary metastasis?

INTRODUCTION: The number of patients diagnosed with solid carcinomas is increasing, and the most common site of metastasis is the lungs. It is often difficult to make a differential diagnosis between primary lung carcinoma and metastatic lung tumor in using histological examination and by determining their immunohistological status. PRESENTATION: A 64-years-old man presented with dyspnea with chest computed tomography (CT) findings of a pulmonary tumor, and afterwards suffered from a sudden bowel hemorrhaged due to colorectal carcinoma. The histological diagnosis of a pulmonary tumor was poorly differentiated adenocarcinoma. Both Thyroid transcription factor-1 (TTF-1) and Cytokeratin20 (CK20) were immunohistologically negative. Of the some oncogenic mutations investigated, a neuroblastoma RAS viral oncogen homolog (NRAS) codon13 G13D mutation was detected in both the colorectal carcinoma and the pulmonary tumor tissue samples. Based on the result, the pulmonary tumor was diagnosed as a metastasis derived from colorectal carcinoma. DISCUSSION: Recently, examination of the oncogenes of solid carcinomas has been clinically investigated in primary lung caricnoma and in colorectal carcinomas. The clinical advantage of the oncogenic mutation survey is to identify the site, and the type, of amino acid change in detail. This case is a rare successful case of a survey of the oncogenes for giving a differential diagnosis. CONCLUSION: A survey of the oncogenic genes is very useful to make a differential diagnosis between primary lung carcinoma and metastatic lung tumor.

Complete resection of unicentric Castleman disease in the superior mediastinum: A case report.

INTRODUCTION: Castleman disease (CD) is a rare benign lymphoproliferative disorder characterized by benign lymph node hyperplasia in a single site (unicentric CD [UCD]) or in multiple sites (multicentric CD [MCD]). Patients with UCD are usually asymptomatic; however, those with MCD usually develop fever, weight loss, and peripheral lymphadenopathy. CASE PRESENTATION: We describe a case of surgically resected UCD in the superior mediastinum in which the involved lymph node was surrounded by important vessels and trachea, necessitating a median sternotomy for complete resection of the tumor. DISCUSSION: Preoperative diagnosis of UCD in the thorax is very difficult, and surgical resection or excision is necessary. Complete resection is recommended for UCD because it is curative and has a 5-year survival rate of 100%. CONCLUDION: UCD should be included in the differential diagnosis of asymptomatic mediastinal tumors. Surgical resection or excision is preferred to ensure an accurate diagnosis and appropriate treatment if malignant disease cannot otherwise be ruled out.