Renal Neuroendocrine Neoplasms: A Single-center Experience.

Primary neuroendocrine neoplasms (NENs) of the kidney are exceedingly rare malignancies and the available data are very limited. The natural history and response to treatments have not been well characterized. We have described the presenting features, demographic data, tumor characteristics, and treatment outcomes of patients with renal NENs.

We performed a retrospective analysis of the data from all Mayo Clinic patients with a tissue diagnosis of a primary renal NEN. The baseline patient and surgical pathologic features and treatment modalities were collected. The time to recurrence after resection and overall survival (OS) were estimated using survival analysis. The Surveillance, Epidemiology, and End Results data were used to estimate the population-wide incidence and OS.

A total of 17 patients were included in the present study, with a median follow-up of 62.8 months. Distant metastasis was present in 29% at diagnosis, with 76% experiencing distant metastasis at any point; 24% had a horseshoe kidney. Of the 17 patients, 14 had undergone surgical resection with no evidence of disease postoperatively. Ten of these patients had documented recurrence. The median time to recurrence was 18 months (95% confidence interval, 9-46 months). Only 1 of the 10 patients showed a radiographic response to systemic therapy. Of 9 patients, 4 had had stable disease with somatostatin analogs. The median OS was 143 months (95% confidence interval, 50-143 months).

Renal NENs are rare malignancies affecting mostly middle-age patients, with distant metastasis common. Approximately one half of patients will experience stable disease with somatostatin analogs. The OS will usually be > 5 years.

Clinical genitourinary cancer. 2019 Dec 05 [Epub ahead of print]

Patrick W McGarrah, Gustavo F M Westin, Timothy J Hobday, Joseph A Scales, Johann P Ingimarsson, Bradley C Leibovich, Thorvardur R Halfdanarson

Department of Internal Medicine, Mayo Clinic, Rochester, MN., Division of Medical Oncology, Mayo Clinic, Rochester, MN; University Cancer and Blood Center, Athens, GA., Division of Medical Oncology, Mayo Clinic, Rochester, MN., Department of Urology, Mayo Clinic, Rochester, MN; Urology Clinics of North Texas, Plano, TX., Department of Urology, Mayo Clinic, Rochester, MN; Maine Medical Partners Urology, South Portland, ME., Department of Urology, Mayo Clinic, Rochester, MN., Division of Medical Oncology, Mayo Clinic, Rochester, MN. Electronic address: .