Pediatric non-Hodgkin lymphomas should be added to the list of cancers associated with BRCA2 mutations, and survivors of childhood NHL should be considered for genetic counseling, investigators suggest.
Among 1,380 survivors of childhood lymphomas, those who were retrospectively found to be carriers of BRCA2 mutations had a fivefold higher risk for non-Hodgkin lymphoma than controls without cancer, reported Zhaoming Wang, PhD, and colleagues from St. Jude Children’s Research Hospital in Memphis.
“Genetic counseling and the option of BRCA2 genetic testing should be offered to survivors of pediatric or adolescent non–Hodgkin lymphoma, particularly those with a family history of BRCA2-associated cancers,” they wrote in JAMA Oncology.
The investigators had previously reported that BRCA2 was the third-most frequently mutated gene among 3006 survivors of childhood cancers, with the highest number of mutations seen in lymphoma survivors. In that study, 7 of 586 survivors of Hodgkin and non-Hodgkin lymphoma (1.2%) were found to carry BRCA2 mutations.
In the current study, the investigators performed germline whole-genome sequencing on samples from 815 survivors of childhood Hodgkin lymphoma and 748 survivors of non-Hodgkin lymphoma from the St. Jude Lifetime Cohort and Childhood Cancer Survivor studies and compared the data with those of controls without cancer from the Genome Aggregation Database.
They identified mutations in five Hodgkin lymphoma survivors (0.6%) and eight non-Hodgkin lymphoma survivors.
A comparison of cancer risk among lymphoma survivors and controls found that non-Hodgkin lymphoma survivors and BRCA2 carriers had an odds ratio for cancer of 5.0, compared with controls who were not BRCA2 carriers (P less than .001). Among Hodgkin lymphoma survivors the OR for carriers vs. controls was 2.1, but was not statistically significant.
Available family histories for seven of the eight non-Hodgkin lymphoma BRCA2 mutation carriers showed histories of BRCA2-linked cancers, including breast, prostate, and pancreas tumors and malignant melanoma.
“Survivors whose test results are positive for mutation should be offered surveillance for BRCA2-associated cancers, such as breast and ovarian, and counseled about cancer risk–reducing strategies. Currently, it remains unclear whether surveillance for non–Hodgkin lymphoma is associated with early detection of lymphomas or with other medical advantages,” the investigators wrote.
“This study was funded by a grant to St Jude Children’s Research Hospital from the American Lebanese Syrian Associated Charities and by grants to St Jude Children’s Research Hospital from the National Institutes of Health. The authors reported having no conflicts of interest.
SOURCE: Wang Z et al. JAMA Oncology. 2019 Jul 25. doi: 10.1001/jamaoncol.2019.2203.