From the Research
A 3 mm nodule appearing 1 month after partial nephrectomy for T1a chromophobe renal cell carcinoma that is located in the fat anterior to the psoas muscle below the lower pole of the kidney is most likely scar tissue rather than recurrent tumor. The small size (3 mm), short time frame (1 month post-surgery), and location in the surgical field are all consistent with normal healing processes. Chromophobe renal cell carcinomas typically have a favorable prognosis with low recurrence rates, especially for small T1a tumors that have been completely resected, as noted in a study published in the Asian journal of urology 1. However, standard follow-up imaging at 3-6 month intervals is still recommended to monitor for any changes in the nodule's size or characteristics, as suggested by the Journal of endourology 2. If the nodule remains stable or decreases in size on subsequent imaging, this would further support that it represents benign post-surgical changes rather than tumor recurrence. Some studies have reported rare cases of metastasis to unusual locations, such as the psoas muscle, but these are extremely rare and typically occur much later than 1 month post-surgery, as reported in the International journal of urology 3. Given the low risk of recurrence and the likelihood of post-surgical changes, imaging surveillance can be safely deferred until 1 year after surgery, as recommended by the Journal of endourology 2, but close monitoring and clinical judgment should always be exercised. Key factors to consider in the management of this patient include:
- The natural history of chromophobe renal cell carcinoma, which is generally favorable, as described in Annals of medicine and surgery 4
- The potential for post-surgical changes to mimic recurrence on imaging, as discussed in the Journal of endourology 2
- The importance of long-term follow-up to detect any potential recurrence or metastasis, as highlighted in the International journal of surgical pathology 5