Mixed high-grade serous and large cell neuroendocrine carcinoma arising from rectal endometriosis 11 years after hysterectomy.

The malignant gastrointestinal endometriosis transformation is represented by endometriosis-associated intestinal tumors. Endometrioid adenocarcinoma and clear cell adenocarcinoma are most common among the endometrial cancers of all organs. Only four cases of mixed serous carcinoma and large cell neuroendocrine carcinoma have been reported, and all these cases originated from the uterus. A 59-year-old woman with a month's history of bloody stools was admitted. She was stable until the hematochezia occurred but is 11 years post-hysterectomy. A circumferential type-3 advanced upper rectum tumor was seen on colonoscopy. Adenocarcinoma was revealed from the forceps biopsies of the type-3 tumor component. Computed tomography showed narrowed lumen with a thickened rectum wall, a continuing mass, and a component on the anorectal side. Swollen lymph nodes were observed around the rectum, but no distant metastatic lymph nodes or organs were found. To treat the lesion, rectal surgical resection with D3 lymph node dissection was performed. Histological examination revealed combined high-grade serous and large cell neuroendocrine carcinomas. Tumor was contiguous to the endometrium in the sub-serosa. Endometriosis was determined to be the origin of both carcinomas. Therefore, endometriosis-associated intestinal tumors should be included in the differential diagnosis when rectal tumors with cystic structures are found post-hysterectomy.

Localized gastric amyloidosis diagnosed by endoscopic ultrasound-guided fine-needle aspiration.

A 49-year-old man was found to have an elevated lesion on esophagogastroduodenoscopy (EGD) for gastric cancer screening. This lesion had been noted in EGD 13 years earlier, but the patient had not received EGD since then. Endoscopy showed a relatively soft subepithelial lesion (SEL) in the gastric antrum. In addition, endoscopic ultrasonography (EUS) showed a 20-mm-sized, slightly non-uniform hypoechoic mass in the submucosa. Since the diagnosis could not be confirmed by mucosal biopsy, EUS-guided fine-needle aspiration (EUS-FNA) was performed. Hematoxylin-eosin staining of EUS-FNA samples revealed deposition of acidophilic unstructured materials. The structure was positive on Congo red staining, and green polarized light was also observed under a polarizing microscope. Moreover, it was resistant to potassium permanganate reaction, negative for serum amyloid A protein, positive for anti-λ chain antibody, and negative for anti-κ chain, anti-amyloid A, anti-transthyretin, and anti-ß2-microglobulin antibodies. Therefore, the lesion was diagnosed as AL-λ-type amyloidosis. No systemic amyloidosis findings were found; thus, the patient was finally diagnosed with localized gastric AL amyloidosis. If an SEL is seen without disease-specific endoscopic findings, amyloidosis should be included in the differential diagnosis, and EUS-FNA can contribute to obtaining tissue samples in such cases.

Intestinal Behçet disease associated with myelodysplastic syndrome accompanying trisomy 8 successfully treated with abdominal surgery followed by hematopoietic stem cell transplantation: A case report.

RATIONALE: Intestinal Behçet disease (BD) with myelodysplastic syndrome (MDS) is a rare condition that is resistant to various immunosuppressive therapies. Several cases in which hematopoietic stem cell transplantation (HSCT) was effective for intestinal BD with MDS accompanying trisomy 8 have been reported. PATIENT CONCERNS: We report an 18-year-old female with a 7-year history of BD. Colonoscopy demonstrated a huge ulcer in the cecum. Chromosomal examination revealed a karyotype of trisomy 8 in 87% of cells. Bone marrow examination revealed dysplastic cells in multilineages. DIAGNOSES: A diagnosis of intestinal BD associated with MDS accompanying trisomy 8 was made. INTERVENTIONS: The patient underwent ileocecal resection due to microperforations of ileocecal ulcers; she then underwent allogeneic peripheral blood stem cell transplantation (PBSCT) with her mother as a donor. OUTCOMES: After the PBSCT, the patient's symptoms due to BD (fever, oral aphthae, abdominal pain, and genital ulcers) completely disappeared, with no severe adverse events. LESSONS: The present case demonstrates that HSCT including PBSCT might be an effective new therapeutic option for refractory intestinal BD with MDS when immunosuppressive therapy has achieved insufficient efficacy.