A comprehensive analysis of renal cell carcinoma as first and second primary cancers

Objective: Second primary renal cell carcinoma (2nd RCC) refers to renal cell carcinoma (RCC) diagnosed after another unrelated malignancy. This study aims to compare the clinical manifestation, pathology, treatment, and prognostic features of patients with 2nd RCC and first primary renal cell carcinoma (1st RCC).

Materials and methods: Data of the patients with localized RCC were retrospectively collected. They were classified as 2nd RCC or 1st RCC according to a previously diagnosed cancer, including 113 cases of 2nd RCC and 749 cases of 1st RCC.

Results: The most common types of extrarenal malignancies in patients with 2nd RCC include lung, colorectal, breast, gynecological, and gastric cancers. The age and smoking rate of 2nd RCC patients were significantly higher than in those of 1st RCC patients. For 2nd RCC patients, fewer had clinical symptoms and renal masses tend to be smaller. One hundred and eight (95.6%) patients with 2nd RCC received surgical interventions. All patients with 1st RCC underwent renal surgery. More patients with 2nd RCC underwent a partial nephrectomy. Pathologically, there was no significant difference in postoperative pathological types between the 2nd and 1st RCCs. However, the 2nd RCCs were commonly identified in the early stages. The median overall survival (OS) of 2nd RCC patients was 117 months, which was shorter than that of 1st RCC patients.

Conclusions: Second RCC is not uncommon. More attention should be paid to screening for 2nd RCC in cancer survivors. There are some differences between patients with 2nd and 1st RCCs that should be viewed separately.