Greater Ethnic Diversity Needed in Prostate Cancer Genetic Data

Two new studies that will be presented at ESMO Asia Congress 2022 emphasized the need for ethnically diverse prostate cancer genomics data and accessible genetic testing.

The first study has confirmed the existence of variations in the genomic landscape of prostate cancer in Chinese men. Researchers performed targeted genetic sequencing on the tumors of 1,016 Chinese patients and compared the results with data from The Cancer Genome Atlas (TCGA), Memorial Sloan Kettering Cancer Center, and Stand Up to Cancer (SU2C) cohorts representative of White men.

“The most important differences we observed were concentrated in castration-sensitive disease and included lower mutation rates in prostate cancer driver genes such as TP53 and PTEN among Chinese patients compared to the Western cohorts, which may partially account for the better prognosis observed in Asian men in this setting,” reported study author Yu Wei, Fudan University Shanghai Cancer Centre, China.

Tumors in Chinese men had more FOXA1, but less TP53 mutations in locoregional disease. Additionally, in metastatic castration-resistant prostate cancer, Chinese men had fewer TP53, PTEN, and APC mutations compared with White men. According to the researchers, the lower frequency of FOX1A class-2 mutations in Chinese prostate cancer “underscored the mechanistic difference in driving cancer progression between races.”

According to Wei, this raises the question of whether the benefits demonstrated by current standard therapies in clinical trials with Western patients can be translated to the Asian population given the varying treatment responses induced by different driver mutations.

The second study looked at patterns of genetic testing in prostate cancer among oncologists in India. According to the study, prostate cancer is the 12th most common cancer in India and genetic testing has been widely advocated there.

Researchers led by Ganesh Bakshi, of Hinduja National Hospital and Medical Research Centre, Mumbai, India, distributed an online questionnaire to medical and uro-onoclogists in India to assess current practice patterns related to genetic testing; 103 responded.

Genetic testing was advised by the majority (64.1%) of respondents for most prostate cancer patients. A majority (58.3%) also chose to advise genetic testing at the stage of castration-resistant disease. Additionally, more than 88% of patients with a positive family history for prostate cancer were commonly referred for genetic testing.

The most commonly used test was a 15-gene panel that looked at genes that play a role in the homologous recombination repair pathway. Major barriers to testing included affordability (89.3%) and lack of genetic counsellors (70.9%).

References

162MO – Genomic Characterization Revealed From Prospective Clinical Sequencing of 1016 Chinese Prostate Cancer Patients

167P – Genetic Testing for Prostate Cancer: The Indian Scenario