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Missense driver mutations in cancer are concentrated in a few hotspots1. Various mechanisms have been proposed to explain this skew, including biased mutational processes2, phenotypic differences3–6 and immunoediting of neoantigens7,8; however, to our knowledge, no existing model weighs the relative contribution of these features to tumour evolution. We propose a unified theoretical ‘free fitness’ framework that parsimoniously integrates multimodal genomic, epigenetic, transcriptomic and proteomic data into a biophysical model of the rate-limiting processes underlying the fitness advantage conferred on cancer cells by driver gene mutations. Focusing on TP53, the most mutated gene in cancer1, we present an inference of mutant p53 concentration and demonstrate that TP53 hotspot mutations optimally solve an evolutionary trade-off between oncogenic potential and neoantigen immunogenicity. Our model anticipates patient survival in The Cancer Genome Atlas and patients with lung cancer treated with immunotherapy as well as the age of tumour onset in germline carriers of TP53 variants. The predicted differential immunogenicity between hotspot mutations was validated experimentally in patients with cancer and in a unique large dataset of healthy individuals. Our data indicate that immune selective pressure on TP53 mutations has a smaller role in non-cancerous lesions than in tumours, suggesting that targeted immunotherapy may offer an early prophylactic opportunity for the former. Determining the relative contribution of immunogenicity and oncogenic function to the selective advantage of hotspot mutations thus has important implications for both precision immunotherapies and our understanding of tumour evolution.

Women with Li–Fraumeni Syndrome (LFS) often consider risk-reducing mastectomy (RRM) due to extremely high risk of breast cancer at early ages. Data on uptake of RRM in LFS are scarce, and are inferred from experience in women with pathogenic variants (PVs) in BRCA1/2, despite differences in cancer risks. This study evaluated RRM uptake in a cohort of women with LFS. Women (n = 205) with LFS enrolled in NCI’s LFS study reported lifetime cancer diagnoses and mastectomies and completed questionnaires regarding reproductive history, cancer worry and risk perceptions. A subset of women participating in an annual cancer screening study received counseling regarding RRM. 65% (n = 71) of women diagnosed with presumed unilateral breast cancer (n = 109) underwent contralateral RRM over their lifetime. Nearly half (49%, n = 25) of the women who did not complete contralateral RRM within one year of their breast cancer diagnosis (n = 51) developed contralateral breast cancer (median interval = 6 years). Only 18.5% (n = 15) of women without breast cancer history (n = 81) underwent bilateral RRM. Median age at bilateral RRM of 39 years was sub-optimal for breast cancer risk reduction. Contralateral RRM was associated with early genetic diagnosis, participation in the screening study, and fewer prior cancers. Bilateral RRM uptake was associated with having had children, having breastfed, and high cancer worry. Uptake of contralateral RRM is high in women with LFS. The frequency of contralateral breast cancer necessitates active discussion of benefits of contralateral RRM and counseling regarding bilateral RRM should be tailored to the early age at risk of breast cancer onset in LFS. There is a need for research into the survival and long-term benefits of RRM in LFS.

Comprehensive annual screening reduces cancer-related mortality in Li-Fraumeni syndrome (LFS), a cancer-prone disorder caused by pathogenic germline TP53 variants. Blood tests at months 4 and 8 between annual screening are recommended but their effectiveness in early cancer detection has not been established. Interim blood counts and inflammatory biomarkers were evaluated in 132 individuals with LFS (112 adults, 87 female, median age 36 years [range 3–68], median follow-up 37 months [range 2–70]) and test abnormalities were observed in 225 (35%). Thirteen cancers in 12 individuals were diagnosed between annual screenings but only one cancer (colorectal adenocarcinoma) was diagnosed due to an abnormal interim blood test. Fisher’s exact test and generalized estimating equation models found no statistical associations between cancer diagnoses and any test abnormality. Four- and 8-monthly interim screening blood tests may not be of independent benefit for cancer detection in LFS, but annual cancer screening and personalized follow-up remain essential.

Li-Fraumeni Syndrome (LFS) is characterized by risk of multiple primary malignancies in diverse sites, pediatric onset, near complete penetrance by age 70 years, limited options for prevention, and substantial uncertainty regarding disease manifestation and prognosis. Forty-five families, including 117 individuals aged 13–81 years, enrolled in the US National Cancer Institute’s Li-Fraumeni Syndrome Study completed 66 interviews regarding their LFS experiences. An interdisciplinary team used modified grounded theory to examine family distress regarding expectations of loss and change due to likely cancer diagnoses, and the consequences of this likelihood across physical, social, and emotional domains. Disease-free periods were characterized by fearful anticipation of diagnosis or recurrence, uncertainty regarding post-treatment quality of life, and planning for shifts in family dynamics to enable caregiving. The chronicity of waiting for these changes incited dread and inhibited effective coping with the pragmatic, emotional, and existential challenges of the syndrome. Consequently, families reported high burden on roles and resources and limited guidance to prepare for, or achieve resolution with, grief. Anticipatory loss, the experience of bereavement prior to an expected change, distinguishes hereditary cancer risk from a sporadic diagnosis. Such grief is often incomplete in impact or meaning, subjected to rapid or profound change as conditions worsen, and poorly understood. In this study, losses were compounded by profound uncertainty, a chronic feature of LFS, which compromised mourning. Long-term engagement of mental health providers with bereavement training, in partnership with genetics providers, can provide invaluable educational and psychological support to families as they navigate these implacable challenges.