What is the significance of a 3 mm nodule in the fat anterior to the psoas muscle, present one month post-partial nephrectomy for chromophobe Renal Cell Carcinoma (RCC) and persisting over three years?

From the Guidelines

The 3 mm nodule in the fat anterior to the psoas muscle, present one month post-partial nephrectomy for chromophobe Renal Cell Carcinoma (RCC) and persisting over three years, is most likely a post-surgical change rather than a concerning lesion. This conclusion is based on the fact that the nodule has remained stable over time, which is consistent with benign post-surgical changes rather than recurrent renal cell carcinoma 1. The small size of the nodule and its post-surgical appearance also support this conclusion.

Key Considerations

• The nodule's stability over three years suggests that it is not a rapidly growing or aggressive lesion, which is consistent with benign post-surgical changes rather than recurrent RCC 1.
• The fact that the nodule appeared after surgery and has remained stable since then suggests that it may be related to the surgical intervention rather than a new or recurrent tumor 1.
• Continued surveillance imaging is still necessary to ensure that the nodule remains stable and does not show any signs of growth or change, which could indicate recurrent disease 1.

Recommendations

• Continue surveillance imaging to monitor the nodule's stability and ensure that it does not show any signs of growth or change 1.
• Consider the nodule as a post-surgical change rather than a concerning lesion, unless new evidence or changes in the nodule's appearance suggest otherwise 1.
• Avoid unnecessary biopsies or interventions, as the nodule's behavior is consistent with benign post-surgical changes rather than recurrent RCC 1.

From the Research

Significance of a 3 mm Nodule

• The presence of a 3 mm nodule in the fat anterior to the psoas muscle, one month post-partial nephrectomy for chromophobe Renal Cell Carcinoma (RCC) and persisting over three years, is a significant finding that requires careful evaluation 2, 3, 4.
• According to the study by 2, localized renal cell carcinoma (RCC) can recur in nearly all organs of the body, but most commonly in the lung, bone, liver, brain, and renal fossa.
• The study by 3 suggests that one in 5 patients who undergo surgical resection for clinically localized RCC develop local and/or distant recurrences, which can be detected early through surveillance strategies.
• The American College of Radiology Appropriateness Criteria, as discussed in 4, recommend radiologic imaging as the most useful component of surveillance for follow-up of patients with treated or untreated RCC.

Surveillance Strategies

• The study by 2 recommends identical surveillance for completely resected tumors regardless of surgical approach, with a more intense surveillance strategy within the first 5 years.
• The University of California Integrated Staging System (UISS) combines TNM stage, Fuhrman grade, and performance status to categorize patients into 3 different risk groups, as mentioned in 2.
• The study by 3 provides an overview of the evidence regarding optimal surveillance protocols after surgery for RCC, including the rationale supporting surveillance, American Urological Association and NCCN guidelines, and reasons against routine long-term surveillance.
• The use of liquid biopsy biomarkers, such as circulating tumour cells, extracellular vesicles (EVs), and cell-free DNA, may also be useful in diagnosing and monitoring RCC, as discussed in 5.

Clinical Implications

• The presence of a 3 mm nodule in the fat anterior to the psoas muscle may indicate a potential recurrence of RCC, and further evaluation and monitoring are necessary to determine the best course of action 4, 6.
• The study by 6 provides an overview of the epidemiology, diagnosis, and treatment of RCC, highlighting the importance of early detection and surveillance in improving patient outcomes.