All patients with small renal masses detected on imaging should be considered for renal tumor biopsy when there is a likelihood that the results may affect management of the patient, says a new clinical oncology practice guideline from the American Society of Clinical Oncology.

The guideline defines small renal masses as incidentally image-detected, contrast-enhancing renal tumors 4 cm in diameter or less that are usually consistent with stage T1a renal cell carcinoma (RCC). Approximately one-fourth of all small renal masses turn out to be benign lesions such as oncocytoma or metanephric adenoma, and another 25% may be indolent tumors that can be managed more conservatively, the guidelines note.

“Although certain renal tumor histologies have distinct imaging characteristics, current radiologic imaging cannot reliably discriminate benign from indolent or potentially malignant tumors. In addition to the diagnostic dilemma, the natural history of these lesions is variable, and many tumors demonstrate an indolent course,” write Antonio Finelli, MD, of the Princess Margaret Cancer Center in Toronto and colleagues in the Journal of Clinical Oncology (2017 Jan. doi: 10.1200/JCO.2016.69.9645 ).

Not too long ago, nearly all patients with small renal masses would have undergone radical nephrectomy for lesions of any size. Today, however, partial nephrectomy and percutaneous thermal ablation are safe and less debilitating surgical options for many patients, the authors point out. The purpose of the guideline, therefore, is to help clinicians manage patients with clinically localized small renal masses with evidence-based clinical recommendations.

Recommendations summarized

The guideline, developed with consensus from a multidisciplinary panel, includes six evidence-based recommendations, all based on intermediate quality sources, with recommendation strengths running from moderate to strong. In summary, the guideline recommends:

The guideline also offers advice for clinicians on communicating with patients and coordinating all aspects of care in a complex care environment.

“To begin, remember that today’s empowered patient will expect a greater role in his or her care. This means taking steps to ensure the patient is well educated and informed. Clinicians should take the time to orient the patient to his or her care but also make available recommended sources for information, including both print materials and online information,” the guideline authors advise.

They also recommend that clinicians share the details of pathology reports and test results with patients, families, and caregivers using terminology they can understand, including a thorough explanation of cancer staging, tumor types, and clinical options. Patients should also be informed, if appropriate, about the availability of clinical trials.

The guideline is sponsored by ASCO, Dr. Finelli and multiple coauthors disclosed relationships with various drug and/or device companies.