[A Case of Small Thymic Carcinoma with Pleural Dissemination Preoperatively Suspected as Pulmonary Metastasis from Rectal Cancer].

A case was 73-year-old man, who had history of laparoscopic high anterior resection surgery for rectal cancer, followed by adjuvant chemotherapy 2 years ago. Preoperative diagnosis was anterior mediastinal tumor, with multiple intrapulmonary nodules noted, though no increasing tendency. During adjuvant chemotherapy for colorectal cancer, the anterior mediastinal tumor showed some shrinkage, while that and 3 intrapulmonary nodules slowly increased in size after completion, thus rectal cancer pulmonary and mediastinal metastasis were suspected. Complete resection of the intrapulmonary nodules and anterior mediastinal tumor was considered feasible. Thoracoscopic observation revealed multiple small pleural seeding lesions and all speculated to be intrapulmonary metastases before surgery were also pleural lesions. Intraoperative rapid diagnostic findings of a biopsy section revealed possible colorectal cancer metastasis, though histological type was not revealed. Final histopathological diagnosis was pleural dissemination of thymic carcinoma. Lenvatinib was introduced 2 months later for thymic carcinoma with pleural dissemination. Two years after surgery, the anterior mediastinum primary tumor had slightly decreased and the pleural nodules also showed a shrinking tendency. In such cases of small tumor with increasing tendency and irregular margins, thymic carcinoma should be considered when planning treatment.

[A Case of Hypertrophic Pulmonary Osteoarthropathy Associated with Pulmonary Pleomorphic Carcinoma].

Hypertrophic pulmonary osteoarthropathy(HPO)is a tumor-associated syndrome that features the triad of clubbed fingers, periosteal bone growth in long bones, and arthritis, and is often associated with an adenocarcinoma or squamous cell carcinoma. This report presents details of a case of HPO associated with pleomorphic carcinoma, which was relieved by treatment. A 47-year-old woman was presented with a complaint of generalized arthralgia. A physical examination showed swollen joints in the body and clubbed fingers. Chest CT revealed a mass shadow in the left upper lobe and ultrasound- guided biopsy findings led to a diagnosis of non-small cell lung cancer. Furthermore, bone scintigraphy indicated symmetrical accumulation in bones and joints throughout the body. A right upper lobectomy was performed along with combined chest wall resection and mediastinal lymph node dissection with an open chest, and the presence of lung cancer complicated with HPO was indicated. Pathological examination results revealed a diagnosis of pleomorphic carcinoma(pT4N0M0, Stage ⅢA). Systemic arthralgia was resolved on the first postoperative day. One year after surgery, a solitary brain metastasis developed and was removed, with no recurrence at the time of writing. Joint symptoms related to HPO can be expected to improve with treatment of pulmonary lesions, thus aggressive procedures for diagnosis and treatment are desirable.

[A Case of Rectal Neuroendocrine Tumor with a Major Axis of 10.7 mm with Lymph Node Metastasis].

The case is a 50-year-old woman. Colonoscopy performed by a local doctor for the purpose of stool occult blood positive revealed a 15 mm tumor in the lower rectum, biopsy showed chromogranin positive, synaptophysin positive, and Ki-67 index<1% showed a neuroendocrine tumor(NET), G1 was diagnosed and introduced. Colonoscopy revealed a smooth- surfaced circular hemispherical tumor with a lower edge 30 mm from the anal margin and 20 mm from the dentate line, and EUS showed 10.7×5.2 mm in layers 2 to 3. It was visualized as a well-defined hypoechoic tumor. Contrast-enhanced CT examination showed a 12×5 mm mass showing a contrast-enhancing effect, and no lymphadenopathy or distant metastasis was observed. Contrast-enhanced MRI showed no evidence of pelvic lymphadenopathy. Based on the above, it was diagnosed that NET, G1, and infiltration to the submucosa exceeding 10 mm. Although endoscopic resection as a diagnostic treatment was also an option, we determined surgical resection policy, therefore we performed laparoscopic rectal intersphincteric resection and upper D2 dissection. Histopathological findings showed a tumor of 11×8 mm infiltrating the submucosa( 5,000µm)with metastasis to the pararectal lymph nodes, and the diagnosis was T1b, N1, Ki-67 index 3%, Ly1, V1a, NET G2, pStage ⅢB. Her postoperative course was uneventful, and 6 months later, we performed her artificial anal closure. One year after the operation, there are frequent bowel movements but no fecal incontinence and she is alive without recurrence. For rectal NET with a tumor diameter of 10 mm or more, radical surgery with dissection is recommended because of the high risk of lymph node metastasis. In this case lymph node metastasis was observed surgical resection according to the above reason, but endoscopic resection was possible except that the preoperative size exceeded 10 mm to 0.7 mm and the distance from the anus was short, therefore it took some thought to decide the policy.

[A case of nonfunctioning islet cell tumor with extensive calcification].

A 52-year-old man was admitted for detailed examination of a mass with extensive calcification in the tail of the pancreas by fluoro-deoxy glucose-positron emission tomography/computed tomography (FDG-PET/CT). Abdominal CT and magnetic resonance imaging (MRI) findings showed a calcified tumor 5 cm in diameter with a smooth surface. The tumor mainly showed calcification at it center and a partially solid element around it margin which was enhanced in the early phase. With no definiture preoperative diagnossi, we performed distal pancreatectomy and splenectomy. Pathological and immunohistochemical studies revealed a nonfunctioning islet cell tumor with calcification. A nonfunctioning islet cell tumor with central calcification formation as it grew to a maximum diameter of 7 cm is rare. When diagnosing pancreatic tumors it must be kept in mind that some nonfunctioning islet cell tumors of the pancreas can show nontypical features such as calcification formation.