Small Cell Carcinoma of the Rectum Associated With a Tubulovillous Adenoma: An Atypical Case Presentation.

Small cell carcinoma of the rectum (SCCR) is a rare and aggressive neuroendocrine tumor. Its association with a tubulovillous adenoma is an exceptional occurrence, presenting significant implications for diagnosis and treatment. This case report details a 62-year-old male, undergoing treatment for hepatocellular carcinoma, presented with symptoms of diarrhea. A colonoscopy initially suggested a benign tubulovillous adenoma, but the presence of discordant clinical findings led to further evaluation. The final diagnosis, established post-surgery, was SCCR originating from a tubulovillous adenoma. This case highlights the diagnostic challenges when unusual presentations arise from atypical pathological findings, especially in patients with concurrent malignancies. The management followed standard care protocols, including robotic transanal surgery, despite the patient's ongoing HCC treatment. This case adds to the limited existing literature on SCCR, particularly its rare association with a tubulovillous adenoma. It emphasizes the importance of a multi-disciplinary approach in diagnosing and managing rare entities in colorectal cancer while demonstrating the feasibility of standard care in patients with complex comorbidities.

Immature Teratoma With Metastatic Gliosis.

Immature teratomas are rare malignant tumors of the ovary. They are made of immature components of germ cell origin. The incidence of immature teratomas is highest in young adults aged 18 to 39. The prognosis heavily depends on the International Federation of Gynecology and Obstetrics (FIGO) staging system and is influenced by factors such as cell type, tumor grade, capsular rupture, and metastatic risk factors. Initial treatment is complete surgical resection. When indicated, platinum-based adjuvant chemotherapy with bleomycin, etoposide, and cisplatin (BEP) is the treatment of choice. Next-generation sequencing of the tumor can influence treatment in the recurrent setting. Temozolomide is an alkylating agent used to target high-grade gliomas. Bevacizumab is a targeted therapy that interferes with the process of angiogenesis by inhibiting vascular endothelial growth factor (VEGF). We report a 36-year-old female who presented with a 17.6cm x 10.5cm x 24.2cm intraabdominal mass and ascites. Upon tumor resection, she was found to have a stage IIIa, grade 2 immature teratoma of the left ovary, with glial tissue being the metastatic cell type. Disease progression continued despite treatment with BEP. She was then treated experimentally with six months of bevacizumab and temozolomide, given its rarity and targeted therapy for glial tissue. Despite monoclonal antibody therapy, the tumor progressed again and was treated with docetaxel and gemcitabine. A repeat CT of the chest, abdomen, and pelvis demonstrated scattered peritoneal implants that were increasing in size. Chromosome analysis was performed and revealed somatic mutations of MLH1, MSH2, MSH6, and PD-L1. The patient has requested a break from chemotherapy but will be treated with direct immunotherapy when she restarts. This case's importance lies in its rarity because fewer than 10 cases of immature teratomas with metastatic glial tissue are noted in the world's literature. Furthermore, this is the first reported case of this cell type being treated with immunotherapy in the world literature.

Diagnostic pitfalls associated with fine-needle aspiration biopsy in a patient with the myxoid variant of monophasic fibrous synovial sarcoma.

Synovial sarcoma (SS) is one of the most common soft tissue tumors that typically presents in the extremities of young adults, but may occur at any site and affect children during the first decade. Herein we discuss a 12-yr-old male who complained of left foot pain and plantar mass. A fine-needle aspiration biopsy of an 8 cm subcutaneous mass was performed revealing a myxoid spindle cell neoplasm. The cytologic differential diagnosis included a myxoid neurofibroma, neurothekeoma, and a myxoid sarcoma. Subsequent excision of the mass revealed a monophasic fibrous SS with myxoid features. Examination of the tissue by fluorescence in situ hybridization confirmed the presence of characteristic SS SYT gene rearrangement at chromosome 18q11.2. This case underscores that the cytologic distinction of mxyoid spindle cell tumors may be challenging. We report the cytologic features of a myxoid monophasic fibrous SS, and discuss its distinction from other benign and malignant myxoid soft tissue neoplasms.