Primary Small Cell Carcinoma of the Kidney: Disease Characteristics and Treatment Outcomes

Establishment and validation of a nomogram to predict overall survival for patients with primary renal neuroendocrine tumor

Our study aimed to develop a nomogram to predict overall survival (OS) at 1, 3, and 5 years for patients with primary renal neuroendocrine tumor (PRNET). The Surveillance, Epidemiology, and End Results database (2000-2021) was utilized to gather cases and extract data. We performed a multivariate analysis using a Cox proportional-hazards model to identify prognostic factors independently affecting OS. Based on these predictors, a nomogram was constructed and validated internally via a bootstrap resampling method. Finally, we included 266 PRNET patients. The multivariate analysis demonstrated that age, Fuhrman grade, surgery, summary stage, N stage, and histology were prognostic factors independently affecting OS (all P < 0.05). A nomogram was then constructed using the abovementioned predictors, except for the N stage. The bootstrap-corrected concordance index (C-index) of the nomogram was 0.820 (95% CI 0.805-0.835), surpassing the C-index of the TNM stage (0.571, 95% CI 0.550-0.592, P < 0.001). Based on time-dependent C-index results, the nomogram demonstrated a better discriminative ability compared to the TNM staging system. There was a good consistency between the observed values and predicted probabilities indicated by the calibration curves. The nomogram's clinical utility was supported by the decision curve analysis. Additionally, the nomogram can classify PRNET patients into low-risk and high-risk subgroups, with high-risk patients having poorer OS (P < 0.0001). The prognostic nomogram, based on individualized clinicopathological information, may be helpful in predicting survival outcomes for PRNET patients more accurately. Further external validation is required in future studies to confirm our developed nomogram's prognostic accuracy and clinical applicability.

Small cell carcinoma of the kidney treated with immune checkpoint inhibitor/tyrosine kinase inhibitor

Introduction

Small cell carcinoma (SCC) of the kidney is extremely rare. Although the majority of patients with advanced renal small cell carcinoma were treated with a combination of cisplatin and etoposide, the efficacy was limited. We report the first case with renal small cell carcinoma who received nivolumab and cabozantinib.

Case presentation

A 57-year-old woman was referred to our hospital with a massive left kidney mass and several bone, lymph nodes, liver, and lung metastases. A left renal mass biopsy made the diagnosis of small cell carcinoma. Nivolumab and cabozantinib were used in combination therapy. The tumors were stable during the treatment for 4 weeks. However, the treatment was halted due to a serious adverse event, immune-related hemophagocytic lymphohistiocytosis. Although immune-related hemophagocytic lymphohistiocytosis was resolved with corticosteroids, the patient died 3 months after the initiation of nivolumab and cabozantinib.

Conclusion

We reported the first case of renal small cell carcinoma treated with nivolumab and cabozantinib.

Primary renal small cell carcinoma: A case report

BACKGROUND

Small cell carcinoma (SCC) is a malignant tumour that is frequently accompanied by extensive metastasis. Primary renal SCC has typical characteristics related to SCC and is extremely rare, with no uniform treatment standard. Clinical treatment is mainly based on the literature. Here we report the diagnosis and treatment of an interesting case of primary renal SCC.

CASE SUMMARY

We report a tortuous course of treatment for a 68-year-old man. Four years before diagnosis, the patient developed continuous gross haematuria, during which he underwent several ureteral biopsies, ureteral stricture relief, and urine exfoliated cell examinations; however, SCC was not confirmed. One month before radical resection of the renal pelvic carcinoma, the severe haematuria recurred. Computed tomography revealed transitional cell carcinoma in the right kidney and right upper ureter. A preoperative examination exluded the possibility of a pulmonary origin of the tumour, and primary renal SCC was diagnosed. The postoperative pathology findings were suggestive of SCC. The patient was treated with combined chemotherapy but died of tumour progression at 7 mo postoperative.

CONCLUSION

Our patient's disease onset in the context of a succession of regular testing and the fact that it occurred so quickly with perirenal encroachment immediately after diagnosis reveals the cruel and unforgiving side of the disease. Furthermore, patients with poor comprehensive treatment results require new treatment regimens.