Antonino Musolino

Genetic Basis of Breast and Ovarian Cancer: Approaches and Lessons Learnt from Three Decades of Inherited Predisposition Testing

Germline variants occurring in BRCA1 and BRCA2 give rise to hereditary breast and ovarian cancer (HBOC) syndrome, predisposing to breast, ovarian, fallopian tube, and peritoneal cancers marked by elevated incidences of genomic aberrations that correspond to poor prognoses. These genes are in fact involved in genetic integrity, particularly in the process of homologous recombination (HR) DNA repair, a high-fidelity repair system for mending DNA double-strand breaks. In addition to its implication in HBOC pathogenesis, the impairment of HR has become a prime target for therapeutic intervention utilizing poly (ADP-ribose) polymerase (PARP) inhibitors. In the present review, we introduce the molecular roles of HR orchestrated by BRCA1 and BRCA2 within the framework of sensitivity to PARP inhibitors. We examine the genetic architecture underneath breast and ovarian cancer ranging from high- and mid- to low-penetrant predisposing genes and taking into account both germline and somatic variations. Finally, we consider higher levels of complexity of the genomic landscape such as polygenic risk scores and other approaches aiming to optimize therapeutic and preventive strategies for breast and ovarian cancer.

BRCA2 Germline Mutations Identify Gastric Cancers Responsive to PARP Inhibitors

Abstract Despite negative results of clinical trials conducted on the overall population of patients with gastric cancer, PARP inhibitor (PARPi) therapeutic strategy still might represent a window of opportunity for a subpopulation of patients with gastric cancer. An estimated 7% to 12% of gastric cancers exhibit a mutational signature associated with homologous recombination (HR) failure, suggesting that these patients could potentially benefit from PARPis. To analyze responsiveness of gastric cancer to PARPi, we exploited a gastroesophageal adenocarcinoma (GEA) platform of patient-derived xenografts (PDX) and PDX-derived primary cells and selected 10 PDXs with loss-of-function mutations in HR pathway genes. Cell viability assays and preclinical trials showed that olaparib treatment was effective in PDXs harboring BRCA2 germline mutations and somatic inactivation of the second allele. Olaparib responsive tumors were sensitive to oxaliplatin as well. Evaluation of HR deficiency (HRD) and mutational signatures efficiently stratified responder and nonresponder PDXs. A retrospective analysis on 57 patients with GEA showed that BRCA2 inactivating variants were associated with longer progression-free survival upon platinum-based regimens. Five of 7 patients with BRCA2 germline mutations carried the p.K3326* variant, classified as “benign.” However, familial history of cancer, the absence of RAD51 foci in tumor cells, and a high HRD score suggest a deleterious effect of this mutation in gastric cancer. In conclusion, PARPis could represent an effective therapeutic option for BRCA2-mutated and/or high HRD score patients with GEA, including patients with familial intestinal gastric cancer. Significance: PARP inhibition is a potential strategy for treating patients with gastric cancer with mutated BRCA2 or homologous repair deficiency, including patients with familial intestinal gastric cancer, for whom BRCA2 germline testing should be recommended.

Prevalence and indicators of cure of Italian women with vulvar squamous cell carcinoma: A population-based study

Five-year net survival and conditional survival from vulvar squamous cell carcinoma (VSCC) patients in Italy have shown no progress during the past three decades. This study aims to estimate the complete prevalence and multiple indicators of cure. Observed prevalence was estimated using 31 Italian cancer registries covering 47 % of Italian women. A subset of 22 cancer registries was used to estimate model-based long-term survival and indicators of cure, i.e., complete prevalence, cure fraction (CF), time to cure (TTC), proportion of 'already cured' patients, and cure prevalence. In 2018, VSCC patients alive in Italy (complete prevalence) were 6620 or 22 per 100,000 women. The cure fraction (the proportion of newly diagnosed patients who will not die of VSCC) did not change between 2000 and 2010 both for all patients (32 %) and in each age group. The time to cure (5-year conditional net survival >95 %) was 11 years for patients aged ≥44 years, but excess mortality remained for >15 years in the other age groups. This led to a negligible (5 %) proportion of 'already cured' patients (living longer than time to cure). The proportion of patients alive <2 years (21 %) was the same as that of patients surviving ≥15 years. The cure prevalence (patients who will not die of VSCC) was 64 %. A considerable proportion of patients will not be cured even among those who survived ≥5 years. There is an urgent need to reshape the current vulvar care model in Italy.

Indicators of cure for women living after uterine and ovarian cancers: a population-based study

Abstract This study aims to estimate long-term survival, cancer prevalence, and several cure indicators for Italian women with gynecological cancers. Thirty-one cancer registries, representing 47% of the Italian female population, were included. Mixture cure models were used to estimate net survival, cure fraction, time to cure (when 5-year conditional net survival becomes &amp;gt; 95%), cure prevalence (women who will not die of cancer), and already cured (living longer than time to cure). In 2018, 0.4% (121 704) of Italian women were alive after diagnosis of corpus uteri cancer, 0.2% (52 551) after cervical cancer, and 0.2% (52 153) after ovarian cancer. More than 90% of patients with uterine cancers and 83% with ovarian cancer will not die from their neoplasm (cure prevalence). Women with gynecological cancers have a residual excess risk of death &amp;lt;5% at 5 years after diagnosis. The cure fraction was 69% for corpus uteri, 32% for ovarian, and 58% for cervical cancer patients. Time to cure was ≤10 years for women with gynecological cancers aged &amp;lt;55 years; 74% of patients with cervical cancer, 63% with corpus uteri cancer, and 55% with ovarian cancer were already cured. These results can contribute to improving follow-up programs for women with gynecological cancers and supporting efforts against discrimination of already cured ones. This article is part of a Special Collection on Gynecological Cancers.