RESUMEN
Melanoma is a malignant tumor derived from melanocytes. Esophageal melanomas occur infrequently, especially primary amelanotic malignant melanoma of the esophagus (PAMME), which is extremely rare. Here, we report the case of a 74-year-old man with an esophageal amelanotic melanoma on the esophagogastric junction (EGJ) found on esophagogastroduodenoscopy. Radical surgery for the tumor at the EGJ was performed with total gastrectomy and D2 lymph node dissection. Diagnosis of PAMME was confirmed postoperatively by immunohistochemical staining. Four months after the surgery, abdominal computed tomography revealed multiple liver metastases. The patient received seven cycles of nivolumab monotherapy and two subsequent cycles of nivolumab and ipilimumab, and these metastases diminished. Recently, new therapeutic agents including immunotherapy have been developed for malignant melanoma and these agents have the potential of improving the prognosis of PAMME. Here, we present new insights into the diagnosis and therapeutic methods that can be used against primary esophageal melanoma.
RESUMEN
INTRODUCTION: Retroperitoneal mucinous cystic neoplasms are uncommon, and little is known about the etiology of the disease. Malignant forms of these are extremely rare. Here, we report a case of primary retroperitoneal mucinous cystadenocarcinoma (PRMC), which demonstrated unexpectedly aggressive progression despite finding only a limited area of adenocarcinoma. PRESENTATION OF CASE: A 62-year-old woman with a complaint of abdominal discomfort was admitted to the hospital. Abdominal CT and MRI showed multiple large retroperitoneal cysts dislocating the right kidney nearly to the center of the abdomen. Transabdominal resection of the cysts was performed. Those cysts contained 1100ml of mucinous fluids in total. Cytological examination of those fluids revealed no malignant cells. The cyst wall was lined with mucinous epithelial cells, and contained some ovarian-type stroma. Also, there was a focal area of adenocarcinoma in the cyst wall, and the lesion was diagnosed as primary retroperitoneal mucinous cystadenocarcinoma. Eight months later, the patient developed lumbar bone metastasis. Chemotherapy with S-1, an oral fluoropyrimidine, and docetaxel had been begun immediately; however, the disease had rapidly spread in the retroperitoneum. Eventually, the patient died of the disease 15 months after surgery. DISCUSSION: Retroperitoneal mucinous cystic neoplasms are considered to be metaplasia of embryonal coelomic epithelium. Complete excision without rupture is essential. However, variance of biological aggressiveness might exist in PRMCs. CONCLUSION: Retroperitoneal mucinous cystadenocarcinoma is a rare tumor, and it is urgently necessary to elucidate the etiology of an effective therapy for the disease.
RESUMEN
Schwannomas of the colon are rare and difficult to diagnose preoperatively. We report a case of schwannoma of the ascending colon that was resected laparoscopically. A 64-year-old woman was referred to our hospital by her local clinic for further evaluation and management of a submucosal tumor of the ascending colon. A definitive preoperative diagnosis could not be reached despite examinations. Gastrointestinal stromal tumor, leiomyoma and lymphoma were the differential diagnoses. We performed a laparoscopic right hemicolectomy with D2 lymph node dissection. Histological findings with hematoxylin-eosin staining revealed spindle-like tumor cells, and immunohistochemical analysis showed that the tumor was positive for S-100 but negative for c-kit, CD34, smooth muscle actin and desmin, with a Ki-67 index of <5%. Thus, the diagnosis in this case was benign schwannoma of the ascending colon.
