Management of renal cell carcinoma in young patients and patients with hereditary syndromes

The evolving management of small renal masses

Small renal masses (SRMs) are a heterogeneous group of tumours with varying metastatic potential. The increasing use and improving quality of abdominal imaging have led to increasingly early diagnosis of incidental SRMs that are asymptomatic and organ confined. Despite improvements in imaging and the growing use of renal mass biopsy, diagnosis of malignancy before treatment remains challenging. Management of SRMs has shifted away from radical nephrectomy, with active surveillance and nephron-sparing surgery taking over as the primary modalities of treatment. The optimal treatment strategy for SRMs continues to evolve as factors affecting short-term and long-term outcomes in this patient cohort are elucidated through studies from prospective data registries. Evidence from rapidly evolving research in biomarkers, imaging modalities, and machine learning shows promise in improving understanding of the biology and management of this patient cohort.

Inherited kidney cancer syndromes

PURPOSE OF REVIEW

To describe current paradigms for genetic testing, screening, and treatment of patients with inherited kidney cancer syndromes.

RECENT FINDINGS

We describe various new aspects of hereditary kidney cancer. Recent data now support that hereditary kidney cancer may account for 5-8% of kidney cancers diagnosed. Methods of testing have evolved including the introduction of multigene next-generation sequencing panels. We continue to learn more about the natural history and management of classic hereditary cancer syndromes. New emerging conditions with lower kidney cancer penetrance have been recognized adding the growing list of syndromes associated with kidney cancer development. The surgical management strategies of enucleation remain however systemic therapy options are being explored both for localized and advanced settings.

SUMMARY

Genetic predisposition to kidney cancer is likely more common than once thought. Knowledge of clinical manifestation and genetic testing strategies are needed to properly identify and treat patient and their families.

Roles for active surveillance in renal cancer

PURPOSE OF REVIEW

With this review, we describe the most recent advances in active surveillance as well as diagnosis and management of small renal masses (SRMs).

RECENT FINDINGS

We discuss diagnosis, differentiation of solid from cystic lesions, risk prediction and treatment of the SRM. A better understanding of the disease facilitates the use of more conservatory treatments, such as active surveillance. Active surveillance has been increasingly accepted not only for SRM, but also for larger tumors and even metastatic patients. Exiting advances in risk prediction will help us define which patients can be safely managed with active surveillance and which require immediate treatment. Meanwhile, the use of renal tumor biopsies is still an important tool for these cases.

SUMMARY

Active surveillance is an option for many patients with renal masses. Noninvasive methods for diagnosis and risk prediction are being developed, but meanwhile, renal tumor biopsy is a useful tool. A better understanding of the disease increases the number of patients who can undergo active surveillance fully certain of the safety of their management.

Update on Indications for Percutaneous Renal Mass Biopsy in the Era of Advanced CT and MRI

OBJECTIVE. The objective of this article is to review the burgeoning role of percutaneous renal mass biopsy (RMB). CONCLUSION. Percutaneous RMB is safe, accurate, and indicated for an expanded list of clinical scenarios. The chief scenarios among them are to prevent treatment of benign masses and help select patients for active surveillance (AS). Imaging characterization of renal masses has improved; however, management decisions often depend on a histologic diagnosis and an assessment of biologic behavior of renal cancers, both of which are currently best achieved with RMB.

Interaction of germline variants in a family with a history of early-onset clear cell renal cell carcinoma

Background

Identification of genetic factors causing predisposition to renal cell carcinoma has helped improve screening, early detection, and patient survival.

Methods

We report the characterization of a proband with renal and thyroid cancers and a family history of renal and other cancers by whole‐exome sequencing (WES), coupled with WES analysis of germline DNA from additional affected and unaffected family members.

Results

This work identified multiple predicted protein‐damaging variants relevant to the pattern of inherited cancer risk. Among these, the proband and an affected brother each had a heterozygous Ala45Thr variant in SDHA, a component of the succinate dehydrogenase (SDH) complex. SDH defects are associated with mitochondrial disorders and risk for various cancers; immunochemical analysis indicated loss of SDHB protein expression in the patient’s tumor, compatible with SDH deficiency. Integrated analysis of public databases and structural predictions indicated that the two affected individuals also had additional variants in genes including TGFB2, TRAP1, PARP1, and EGF, each potentially relevant to cancer risk alone or in conjunction with the SDHA variant. In addition, allelic imbalances of PARP1 and TGFB2 were detected in the tumor of the proband.

Conclusion

Together, these data suggest the possibility of risk associated with interaction of two or more variants.

Trends in reporting histological subtyping of renal cell carcinoma: association with cancer center type

Histological classification of renal cell carcinoma (RCC) has become increasingly important for clinical management. We identified 295483 RCC diagnosed from 1998-2014 in the National Cancer Database (NCDB) to examine temporal trends in proportions of RCC with unspecified histology and several specific histologies from the 1998 and 2004 World Health Organization classifications of RCC. Further, multivariable log binomial analysis of 101062 RCC diagnosed from 2010 to 2014 was used to determine whether the association of diagnosing/treating facility type and the proportion of unspecified RCC is independent of patient demographic and clinical factors. Between 1998 and 2014, the proportion of histologically unspecified RCC decreased substantially in all facility types, with the decrease smallest in community programs (from 86.0% to 28.1%) and largest in National Cancer Institute-designated centers (from 85.1% to 9.8%). These decreases were offset by increases in percentages of papillary, clear cell, and chromophobe RCC cases. During 2010 to 2014, relative to community programs, RCCs were 21% less likely to be reported as unspecified histology (adjusted prevalence ratio [aPR] = 0.79; 95% CI, 0.68-0.92) in comprehensive community programs, 32% less likely in integrated network programs (aPR = 0.68; 95% CI, 0.57-0.92) and academic programs (aPR = 0.68; 95% CI, 0.54-0.87), and 63% less likely (aPR = 0.37; 95% CI, 0.26-0.52) in National Cancer Institute -designated programs. These results have implications for the optimal selection of targeted systemic therapies for patients with advanced disease, and for the potential value of cancer registry data in pathology quality improvement programs to promote more rapid and consistent adoption of new classifications of RCC and other neoplasms.