AUA 2018: Somatic Mutation in Mitochrondrial DNA Predicts Postoperative Recurrence in Renal Cell Carcinoma.

San Francisco, CA USA (UroToday.com) While it is well-known that DNA mutations and errors in replication increase risk of cancerous cell growth, it is less-known that mutations in mitochondrial DNA (mtDNA) may be a similarly-important influencer. Even further, given that mtDNA mutations occur at a 10-fold higher rate than nuclear DNA, early detection can pose significant advantage in predicting disease progression and postoperative recurrence of RCC.

Dr. Kim, from Isehara Japan, presented a study examining the correlation between ND1 and D-loop mtDNA mutations and postoperative RCC recurrence in 61 patients [47 male, 14 female, median age 62 years] who underwent radical nephrectomy for localized RCC. Clinicopathologic data, ND1 and D-loop mutations, and postoperative mutations at a median follow-up of 66.5 months were correlated via cox regression.

At follow-up, 16.4% (10/61) had recurrent RCC, all of which had mtDNA mutations. Subsequently, in multivariate analysis, mtDNA was significantly associated with a lower 5-year recurrence free survival rate. Of note, the team notes that there may be a risk of false negatives, given that 14 of the 61 patients had a mtDNA mutation and have not yet recurred at 5-years post-op.

While this is the first study that demonstrates a relationship between mtDNA mutations and recurrent RCC, the implications of an early metric of recurrence are profound. As biomarkers, ND1 or D-loop mtDNA mutations can assist in risk stratification, patient-physician decision-making, and improved clinical outcomes.

Presented by: Hakushi Kim, MD

Written by: Linda My Huynh, Department of Urology, University of California-Irvine at the 2018 AUA Annual Meeting - May 18 - 21, 2018 – San Francisco, CA USA