Major advances have been made in CRC treatment in recent years, especially in molecularly driven therapies and immunotherapy. Despite this, a large number of advanced colorectal cancer patients do not benefit from these treatments and their prognosis remains poor. The landscape of DNA damage response (DDR) alterations is emerging as a novel target for treatment in different cancer types. PARP inhibitors have been approved for the treatment of ovarian, breast, pancreatic, and prostate cancers carrying deleterious BRCA1/2 pathogenic variants or homologous recombination repair (HRR) deficiency (HRD). Recent research reported on the emerging role of HRD in CRC and showed that alterations in these genes, either germline or somatic, are carried by up to 15–20% of CRCs. However, the role of HRD is still widely unknown, and few data about their clinical impact are available, especially in CRC patients. In this review, we report preclinical and clinical data currently available on DDR inhibitors in CRC. We also emphasize the predictive role of DDR mutations in response to platinum-based chemotherapy and the potential clinical role of DDR inhibitors. More preclinical and clinical trials are required to better understand the impact of DDR alterations in CRC patients and the therapeutic opportunities with novel DDR inhibitors.

Opinion statement: Around 90% of breast tumours are diagnosed in the early stage, with approximately 70% being hormone receptor-positive. The cornerstone of adjuvant therapy for early-stage hormone receptor-positive breast cancer is endocrine therapy, tailored according to disease stage, biological characteristics of the tumour, patient’s comorbidities, preferences and age. In premenopausal patients with hormone receptor-positive breast cancer, ovarian function suppression is a key component of the adjuvant endocrine treatment in combination with an aromatase inhibitor or tamoxifen. Moreover, it can be used during chemotherapy as a standard strategy for ovarian function preservation in all breast cancer subtypes. In the metastatic setting, ovarian function suppression should be used in all premenopausal patients with hormone receptor-positive breast cancer to achieve a post-menopausal status. Despite its efficacy, ovarian function suppression may lead to several side effects that can have a major negative impact on patients’ quality of life if not properly managed (e.g. hot flashes, depression, cognitive impairment, osteoporosis, sexual dysfunction, weight gain). A deep knowledge of the side effects of ovarian function suppression is necessary for clinicians. A correct counselling in this regard and proactive management should be considered a fundamental part of survivorship care to improve treatment adherence and patients’ quality of life.

Multigene germline panel testing is recommended for Pancreatic Cancer (PC) patients; however, for non-BRCA1/2 genes, the clinical utility is unclear. A comprehensive multi-gene assessment in unselected Italian PC patients is missing. We evaluated the prevalence and impact of Pathogenic Variants (PV) in 51 PC susceptibility genes in a real-world series of 422 Italian PC patients unselected for Family History (FH), compared the clinical characteristics and conducted survival analyses. 17% of patients had PVs (70/422), mainly in BRCA1/2 (4.5%, all 50 y), ATM (2.1%). PV carriers were younger (64 vs. 67; p = 0.02) and had more frequent personal/FH of PC, melanoma and breast/ovarian cancer (all p < 0.05). The Overall Survival (OS) was longer in patients carrying PVs (HR 0.78; p = 0.090), comprising ATM carriers (HR 0.33; p = 0.054). In the oxaliplatin-treated subset, PV carriers showed better control of the disease, although this was not statistically significant (67% vs. 56%). CDKN2A, BRCA2 and ATM were the most frequently altered genes. ATM PVs were positively associated with OS in 41% of PV carriers, 60% of whom carried CDKN2A,BRCA2 or ATM PVs, had negative FH and would have been missed by traditional referral. Thus, CDKN2A and ATM should be added to BRCA1/2 testing regardless of FH.

At the end of the past century, the introduction of Total Mesorectal Excision (TME), preceded by either short-course radiotherapy (SCRT) or chemoradiation (CRT), established the new standard of care for locally advanced rectal cancer (LARC). Recently, significant advancements were achieved for both dMMR/MSI and pMMR/MSS LARC patients. For the 2–3% of dMMR/MSI LARCs, ablative immunotherapy emerged as a curative approach, offering the possibility of avoiding chemotherapy (CT), radiotherapy, and surgery altogether. In pMMR/MSS LARCs, the intensification of preoperative treatments with Total Neoadjuvant Treatment (TNT) afforded three outcomes: (a) a reduction of distant metastases, positively impacting on survival endpoints, (b) a significant increase of complete clinical response (cCR) rate, paving the way for non-operative management (NOM), and (c) the selective omission of radiotherapy following induction CT. The choice of the most appropriate therapeutic strategy can only be made through the shared decision-making process between physician and patient based on risk stratification and patient preferences.

Recent studies have shown that immune-related adverse events (irAEs), occurring even after the discontinuation of immune checkpoint inhibitors (ICIs), may be associated with favorable disease outcomes, particularly in patients with melanoma and lung cancer. However, a few clinical cases have been described on the correlation between irAEs and ICIs efficacy in renal cell carcinoma (RCC) patients. This study reports the clinical case of a metastatic RCC patient who has experienced severe immune-related renal toxicity after 19 months of nivolumab use. Despite immunotherapy discontinuation, the patient has maintained clinical benefit and disease progression-free for 3 years. We examined the correlation between the occurrence and the severity of irAEs, treatment discontinuation and clinical benefits. The evidence on ICI retreatment following ICI discontinuation due to irAEs was also reviewed. Lay abstract Immunotherapy has profoundly changed the treatment scenario of cancer patients. However, similar to any oncological therapy, it may cause immune-related adverse events. Cancer patients experiencing immune-related adverse events have a higher probability of better survival outcomes. This correlation has been largely described in patients with melanoma and lung cancer, but only a few data have been reported for genitourinary tumor patients. Here, we report the clinical case of a metastatic renal cell carcinoma patient who has experienced a late-onset and severe immune-related renal toxicity after 19 months of immunotherapy, which led to treatment discontinuation. Despite this, the patient has maintained a clinical benefit and disease progression-free for more than 3.5 years. We reviewed the literature on the correlation between immunotherapy benefit and immune-related adverse events, considering the time of onset, the severity of the adverse events and the concepts of treatment discontinuation and retreatment.