FROM JAMA ONCOLOGY
Broader cancer screening of individuals with Li-Fraumeni syndrome (LFS), with or without whole-body magnetic resonance imaging, has a good diagnostic yield and identifies a wide range of cancers, according to a preliminary analysis of the ongoing LIFSCREEN phase 3, randomized, controlled trial.
Investigators led by Olivier Caron, MD, chair of the oncogenetics committee, department of medical oncology, at the Gustave Roussy University Hospital in Villejuif, France, enrolled in the trial 107 individuals from 75 families carrying a TP53 mutation, a genetic aberration commonly present in LFS that confers heightened risk of a variety of malignancies.
Participants had a median age at baseline of 32.9 years, with a range from 5 to 67 years. Fully 98% had a family history of cancer, and 48% had a personal history of cancer.
The participants were assigned to 5 years of standard screening – annual clinical examination, abdomen and pelvis ultrasound, brain MRI, complete blood cell count, and, for women older than 20 years, breast ultrasound and MRI – or intensive screening, entailing the addition of diffusion whole-body MRI.
At the time of the preliminary analysis, 15 patients had undergone only one round of screening; 35, two rounds; 19, three rounds; 24, four rounds; and 7, five rounds, Dr. Caron and associates reported in a research letter (JAMA Oncol. 2017; Aug 3 doi: 10.1001/jamaoncol.2017.1358 ).
Collectively, this amounted to 226.4 person-years of follow-up.
Screening with either trial strategy (with or without whole-body MRI) led to diagnosis of 23 new primary cancers in 20 patients. Nearly half of the total (12 cancers) were detected at the first round. Patients had a median age of 39.8 at the new cancer diagnosis, with a range from 6 to 70 years.
Of the new cancers, 10 belonged to the core LFS spectrum of breast cancer, sarcoma, and brain tumors. However, the other 13 were outside that spectrum, for example, lung adenocarcinomas, all seen in never or light smokers, and leukemias. Screening also detected three relapses of previous cancers.
Analyses further showed that prior cancer diagnosis was not a reliable marker for risk of new primaries. Although 12 of the patients with a screening-detected new primary had a personal cancer history, 8 did not (P = .22).
“The proportion and diversity of off–core LFS spectrum cancers detected in TP53 mutation carriers as reported by others give growing evidence of a broader LFS spectrum, in agreement with the permissive role of TP53 mutations,” write Dr. Caron and colleagues, who report having no relevant disclosures. “Our observations seem to support recent moves toward broader cancer screening in TP53 mutation carriers.”
The investigators continue to collect data in LIFSCREEN and plan to undertake main analysis later this year. “Our final analysis will help to determine the benefits and drawbacks (mostly related to false-positive test results) of whole-body MRI in TP53 mutation carrier surveillance,” they conclude. “Studies focused on TP53 mutation penetrance, using methods limiting selection bias, are required to refine cancer risks to improve TP53 mutation carrier management.”
