[A Case of Giant Abdominal Desmoid Tumor in a Young Man].

Desmoid tumor is a rare tumor of the soft tissue. The frequency of occurrence is 2.4 to 4.3 cases per year per million people, which is a very rare disease. We experienced a huge intra-abdominal desmoid tumor which is thought to be the primary mesentery. The case was a male in his 20s. He visited a nearby doctor with a complaint of abdominal bloating and abdominal pain. Abdominal contrast CT revealed a huge abdominal mass with a clear boundary of 35×25 cm in size extending from the upper right abdomen to the pelvis. Surgery was performed with a diagnosis of an intra-abdominal mass. Open abdominal tumor resection. Due to infiltration into the duodenum, transverse colon, and pancreas, right hemicolectomy and duodenal combined resection were performed. The pathological diagnosis was a diagnosis of desmoid tumor.

[A Case of Primary Hepatic Mucosa-Associated Lymphoid Tissue Lymphoma].

A 74-year-old man with no chronic liver disease was admitted for an incidental liver tumor by computed tomography. Serological examinations for hepatitis B and C virus were negative and tumor markers, including carcinoembryonic antigen, α-fetoprotein, carbohydrate antigen 19-9, and des-gamma-carboxy prothrombin, were within the normal range. The contrast- enhanced magnetic resonance imaging revealed that the 26 mm in diameter patchy tumor occupied the S7 in the liver. The tumor boundary was enhanced slightly in the arterial phase and inside gradually in the portal phase, and the enhancement was faded in the late phase. As a characteristic finding, vessels penetrated the tumor. The tumor was diagnosed as cholangiocarcinoma, and the patient underwent right lateral sectionectomy. After 19 days postoperatively, the patient was discharged. The diagnosis of hepatic mucosa-associated lymphoid tissue(MALT)lymphoma was made by pathological examination. Currently, the patient has no recurrence for 5 months without adjuvant chemotherapy. The primary hepatic MALT lymphoma is a rare disease among primary hepatic malignant lymphomas. The patient must be followed up carefully because 2 cases were reported as recurrent cases after several years postoperatively although the disease has a good prognosis.

[A Case of Laparoscopically Resected Sigmoid Colon Cancer and Transverse Colon Mesentery Primary Solitary Fibrous Tumor].

The patient is a 52-year-old woman who visited the general practitioner because of positive fecal occult blood test by medical examination. The patient underwent colonoscopy at the hospital, which revealed sigmoid colon cancer. Therefore, the patient was referred to our hospital for surgery. Preoperative CT scan revealed a well-defined and lobulated 54 mm tumor on the caudal side of the duodenal third portion. On MRI, the tumor showed low T1-weighted image signal and high T2-weighted and diffusion-weighted images signal, with low ADC. For preoperative diagnosis, we diagnosed sigmoid colon cancer and transverse colon mesenteric and performed laparoscopic sigmoid colon and transverse colon mesenteric tumor resections. The histopathological tumor diagnoses were sigmoid colon cancer(S, type 2, 30×30 mm, 1/2 circumference, moderately differentiated adenocarcinoma, pT3[SS], INF b, Ly1a, V1a, pN1b[#252: 2/4], sM0, fStage Ⅲb)and transverse colon mesentery primary solitary fibrous tumor. The patient was treated with XELOX as the adjuvant chemotherapy and survived without recurrence until present.

[A Case of Giant Pancreatic Mucinous Cystic Neoplasm That Was Difficult to Preoperative Diagnosis].

A 43-year-old woman with about abdominal distension was referred to our hospital for a more detailed examination. Abdominal CT showed 27 cm-sized cystic lesion with the calcification along the partition wall and a nodular hyperplasia. We suspected pancreatic pseudocyst, primary retroperitoneal tumor and we performed tumorectomy. The resected specimen had a maximum diameter of 27 cm. The histopathological diagnosis was mucinous cystadenocarcinoma of the pancreas with ovarian-type stroma. The adjuvant chemotherapy treated with gemcitabine was selected for 3 courses. She continues to do well without any recurrences 7 months later.

[A Case of Gastric Cancer Performed Curative Operation after Nivolumab].

A 69-year-old man was admitted for the severe anemia. Upper gastrointestinal endoscopy revealed type 3 gastric cancer (por1, HER2 negative)that spread from EG junction to the lesser curvature of lower gastric body. CT revealed LNs metastasis and the direct invasion to the diaphragm. We diagnosed the locally advanced gastric cancer(T4bN[+]M0, Stage ⅣA) and planed neoadjuvant chemotherapy. After 3 courses of S-1 plus CDDP therapy, serum CEA level increased. And the invasion to diaphragm was unclear although the tumor shrunk. After 3 courses of nab-PTX plus RAM therapy as the second- line, the tumor was PD. As the third-line chemotherapy, nivolumab therapy was repeated up to a total of 15 courses. As the tumor was PR, the patient underwent total gastrectomy with D2 lymphadenectomy. The histopathological examination revealed that the cancer invaded into the muscle layer without lymph nodes metastasis. The cancer was diagnosed as pT2 (MP)N0M0, Stage ⅠB. The cancer cells were EB virus positive and MSI-high. CD 8 positive T lymphocytes infiltrated into the stroma. The patient is alive 26 months without adjuvant chemotherapy. The curative operation was able to perform because the infiltrative CD8 positive T lymphocytes reactivated with nivolumab responded remarkably.

[A Case of Pseudo-Meigs' Syndrome Caused by Ovarian Metastasis from Colon Cancer].

This case pertains to a female patient in her 60s who was diagnosed with carcinoma in the cecum with lung, ovarian, and peritoneal metastases. She complained of abdominal distension and poor feeding because her ascites and ovarian metastasis worsened 18 months after chemotherapy initiation. Repeated cytologic examination of the ascitic fluid revealed no malignant cells. Therefore, Pseudo-Meigs' syndrome was suspected. Bilateral salpingo-oophorectomy was performed as palliative surgery because of the patient's reduced capacity to perform activities of daily living(ADL)due to ascites. After palliative surgery, her ascites disappeared, and she was able to better perform ADL. Further, chemotherapy was resumed. The patient remains well 10 months after surgery. This case highlights the importance of considering Pseudo-Meigs' syndrome in patients with massive ascites and ovarian metastasis, because surgical resection can improve their quality of life.