Dados do Trabalho

Título

SMALL CELL RENAL CARCINOMA WITH NEUROENDOCRINE DIFFERENTIATION IN 22-YEAR-OLD PATIENT: CASE REPORT

Apresentação do caso

22-year-old female with chief complaint of pain in left flank with irradiation to lower abdomen underwent USG that showed a left kidney with heterogeneous mass measuring 6.5 cm in the lower pole. Urinary tract CT revealed an enlarged left kidney with 6.9 cm partially exophytic hypodense expansile formation affecting the middle and lower third, apparently extending to the renal pelvis. Left radical nephrectomy (RN) was performed on 08/21/19, resulting in lesion-free margins, consisting of small and intermediate cells forming solid blocks, with tubular phenotype and moderate atypia, in addition to frequent apoptotic bodies. Immunohistochemistry was consistent with small cell neuroendocrine carcinoma, with positive CK markers AE1AE3 and CD56. A PET CT on 09/09/19 showed hypoattenuating nodules in the left renal pocket of 1.8cm (Suvmax=11.9), and in peritoneal topography, measuring 1.1cm in the left parieto-colic region (Suvmax=15), and perioaortic lymph nodes measuring 1.5x1.1cm (Suvmax=12.2). Chemotherapy regimen (ChT) was initiated on 09/14/19, with 4 cycles of etoposide and cisplatin, with complete clinical and radiological response. 13 months after RN, a CT revealed heterogeneous expansile mass measuring 5.4 x 8.2 x 6.4 cm in the bottom of the posterior sac, causing anterior displacement of the bladder, uterus and rectum. ChT of 2nd line with cyclophosphamide, doxorubicin and vincristine was proposed. 3 months later, a new CT scan showed, in addition to the adnexal cystic formations and the retrouterine mass, nodular formation with soft parts consistency next to the left iliac vessels. She was submitted to rescue surgery, but no resection was performed due to diffuse carcinomatosis. The new immunohistochemical test confirmed neuroendocrine neoplasia of small cells, with 70% Ki-67. A new ChT with irinotecan and cisplatin was tried for 3 cycles, but evolved with liver metastases and progression of the disease in the pelvis, being in palliative care.

Discussão

Primary neuroendocrine kidney tumors are rare, and in 2009, there were only 42 cases reported on Pubmed. The carcinogenesis
pathway is associated with loss of p53 and amplification of Myc, which differs from the carcinogenesis of clear cell cancer and carries a poor prognosis compared to the usual renal cell cancer.

Comentários finais

This is a case report of a young patient with small cell neuroendocrine cancer of kidney, which must be highlighted, given its rarity.

Palavras-chave

Small Cell Carcinoma. Neuroendocrine. Kidney.