Tina Sidoni

Prevalence of BRCA1 and BRCA2 genomic rearrangements in a cohort of consecutive Italian breast and/or ovarian cancer families

Germline point mutations in BRCA1 and BRCA2 genes account for about 30% of the inherited breast and ovarian cancers. Germline genomic rearrangements have been found in both BRCA1 and BRCA2 genes, but the extent to which these alterations might contribute to increasing the actual mutation detection rate is still debated. Here we screened a cohort of 112 consecutive Italian families at moderate-to-high risk for breast and/or ovarian cancer for BRCA1 and BRCA2 point mutations and genomic rearrangements. Of the 83 point mutation negative probands, two (2.4%) showed BRCA1 rearrangements, accounting for 10.5% of the BRCA1 mutations. BRCA1 del18–19 has been previously described in another Italian family, while the molecular characterization of the BRCA1 del23–24 is given here for the first time. Conversely, we failed to identify any BRCA2 rearrangements even in the hereditary breast cancer families, where we detected an higher prevalence of BRCA2 compared to BRCA1 point mutations. Our results support the idea that search for BRCA1 rearrangements should be included in the genetic screening of even moderate risk breast/ovarian cancer families. In contrast, they suggest BRCA2 rearrangements might be very rare out of the high risk families including a male breast cancer.

Novel BRCA1 and BRCA2 germline mutations and assessment of mutation spectrum and prevalence in Italian breast and/or ovarian cancer families.

Familial aggregations of breast/ovarian cancer cases frequently depend on BRCA1/2 pathogenic mutations. Here we counselled 120 Italian breast/ovarian cancer families and selected 73 probands for BRCA1/2 mutation screening. Through this analysis we defined the prevalence of BRCA1/2 pathogenic mutations occurring in Italian breast/ovarian cancer families, enlarged the spectrum of Italian BRCA1/2 mutations by 15% and report on the identification of 13 novel variants, including two deleterious truncating mutations and two potentially pathogenic missense mutations, on the BRCA1 and BRCA2 genes. Finally in hereditary breast cancer families with three or more female breast cancer cases we observed a low mutation prevalence and a significant association with BRCA2 mutations.

Improving the accuracy of BRCA1/2 mutation prediction: validation of the novel country-customized IC software

Inherited mutations of the BRCA1/2 genes confer a significantly increased risk for breast and/or ovarian cancer development. Several models were elaborated to help genetic counsellors in selecting individuals with high probability of being mutation carriers. The IC software, a country-customized version of the Brcapro model, was recently shown to be particularly accurate in the prediction of carrier probability status in the Italian population. Here, we used our independent series of 70 breast/ovarian cancer families to analyze the performances of the IC software and compare it to widely used models, such as Brcapro and the Myriad mutation prevalence tables. Analysis of the areas under the receiver operator characteristics (ROC) curves indicated that overall the models performed well. However, the IC software and Myriad tables were more efficient in predicting mutated cases, showing a higher sensitivity (94 and 88%, respectively) and negative predictive value (NPV, 94 and 92%, respectively) compared to Brcapro (sensitivity 71 and NPV 83%). IC software also appeared particularly accurate in the identification of families belonging the low mutation risk group (<10%). Finally, most Brcapro failures occurred in the hereditary breast cancer (HBC) family subset, and in 75% of the cases, the IC software corrected them. Our data suggest that the country-customized implementation operated on the Brcapro software generated a more accurate tool for the prediction of BRCA1/2 gene mutation. Whether the IC or other country-customized models might improve BRCA1/2 mutation prediction also in non-Italian families needs to be further explored.

Bone targeted therapy for preventing skeletal-related events in metastatic breast cancer

Cancer cells can alter physiological mechanisms within bone resulting in high bone turnover, and consequently in skeletal-related events (SREs), causing severe morbidity in affected patients. The goals of bone targeted therapy, as bisphosphonates and denosumab, are the reduction of incidence and the delay in occurrence of the SREs, to improve quality of life and pain control. The toxicity profile is similar between bisphosphonates and denosumab, even if pyrexia, bone pain, arthralgia, renal failure and hypercalcemia are more common with bisphosphonates, while hypocalcemia and toothache are more frequently reported with denosumab. Osteonecrosis of the jaw (ONJ) occurred infrequently without statistically significant difference. The present review aims to provide an assessment on bone targeted therapies for preventing the occurrence of SREs in bone metastatic breast cancer patients, critically analyzing the evidence available so far on their effectiveness, in light of the different mechanisms of action. Thus, we try to provide tools for the most fitting treatment of bone metastatic breast cancer patients. We also provide an overview on the usefulness of bone turnover markers in clinical practice and new molecules currently under study for the treatment of bone metastatic disease.

Neoadjuvant chemotherapy in breast cancer: a dose-dense schedule in real life and putative role of PIK3CA mutations

Background Dose-dense chemotherapy is one of the treatments of choice for neoadjuvant therapy in breast cancer (BC). Activating mutations in PIK3CA gene predict worse response to neoadjuvant chemotherapy for HER2-positive patients, while their role is less clearly defined for HER2-negative tumors. Methods We conducted a phase I/II study of neoadjuvant, sequential, dose-dense anthracycline/taxane chemotherapy, plus trastuzumab in HER2-positive patients and investigated the correlation of pre-treatment PIK3CA mutation status with pathologic complete response (pCR) and long-term outcome in a real-life setting. Results we established a dose-dense docetaxel recommended dose of 60 mg/m2 and 65 mg/m2, with or without trastuzumab, respectively, according to HER2-status, following dose-dense epirubicin-cyclophosphamide (90/600 mg/m2), every 2 weeks. The overall pCR rate was 21.4%; median disease-free survival (DFS) was 52 months and median overall survival (OS) was not yet reached. PIK3CA mutation status was not significantly associated with the pCR rate: 18% for both mutated and wild-type patients. The pCR rate was: 25% in the mutated and 24% in the wild-type (p 0.560) cohort of the HER2-positive subgroup; 33% both in the mutant and wild-type cohort of the triple-negative subgroup; no pCR neither in the mutant nor in the wild-type cohort of the HR-positive/HER2-negative subgroup. Among the HER2-positive population, a trend toward worse DFS was observed in case of mutation, as opposed to the triple negative population. Conclusions This study proposes an effective and safe neoadjuvant dose-dense anthracycline/taxane schedule and suggests that PIK3CA mutation analysis can be usefully performed in real-life clinical practice.

The possible different roles of denosumab in prevention and cure breast cancer bone metastases: A ‘hypothesis‑generator’ study from clinical practice

The most frequent site of recurrence in breast cancer (BC) is the bone, particularly in patients with ‘luminal-like’ disease. Denosumab has been shown to prevent aromatase inhibitors (AIs) induced bone resorption in postmenopausal early BC patients and reduce skeletal-related events (SREs) in bone metastatic breast cancer (BMBC). A ‘real life’ analysis of 90 BMBC patients treated with denosumab was performed. Eighty-six patients (95.6%) had ‘luminal-like’ disease, 72 (80%) had bone metastases at the time of first recurrence of disease. Among 50 patients with metachronous ‘luminal-like’ disease, 40 (80%) had first recurrence to the bone. Among these patients median time to skeletal recurrence (TSkR) was shorter for patients who were previously exposed to AIs compared to those who were not (53.0 vs. 102.0 months, respectively; P=0.0300) and longer for patients previously treated with tamoxifen compared to those who were not (102.0 vs. 59.0 months, respectively; P=0.0466). Both of them were not confirmed at multivariate analysis. In the overall population, 17 first SREs were observed (16 radiation therapy) and median time to first SRE was not reached. A statistically significant difference in the incidence of SREs was detected only between patients with exclusively osteolytic bone metastases vs. those without (P=0.013). The presence of exclusively-osteolytic bone metastases was the only factor significantly associated with a shorter time to first SRE (P=0.011). The only G3 toxicity reported was hypocalcemia in one patient. No osteonecrosis of the jaw events (ONJ) occurred. This study demonstrated that a pro-active attitude enables the treatment of the majority of patients with denosumab without significant class-related toxicities. The majority of SREs were from radiation therapy, so pain still remains the clinical hallmark of bone metastases, particularly for osteolytic ones. The suggestion that estrogen deprivation with AIs can favor a ‘bone-related’ risk conditions for developing bone metastases must be considered with caution and surely needs further validations.

Prognostic significance of clinicopathological factors in early breast cancer: 20 years of follow-up in a single-center analysis

Background To quantify the effect of traditional prognostic factors [nodal status, estrogen-receptor (ER), progesterone-receptor (PR), human epidermal growth factor receptor 2 (HER2)] on long-term outcome of patients with early breast cancer (EBC), treated in clinical practice over a period of about twenty years. Results 1198 consecutive patients were identified. Median DFS (disease-free survival): ER+/PR±/HER2−, 165 months (mo) if node-negative (N0) and 114mo if node-positive (N+) (p < 0.001); triple-negative (TN), 109mo if N0 and 65mo if N+ (p 0.144); ER+/PR±/HER2+ in patients not-treated with adjuvant trastuzumab (T−), not reached if N0 and 114mo if N+ (p 0.297); ER+/PR±/HER2+ in patients treated with trastuzumab (T+), 95mo if N0 and 85mo if N+ (p 0.615); ER−/PR−/HER2+ T−, not reached if N0 and 26mo if N+ (p 0.279); ER−/PR−/HER2+ T+, not reached if N0 and 66mo if N+ (p 0.014). Median OS (overall survival): ER+/ PR±/HER2−, 166mo if N0 and 144mo if N+ (p 0.028); TN, 158mo if N0 and 96mo if N+ (p 0.384); ER+/PR±/HER2+ T−, not reached if N0 and 157mo if N+ (p 0.475), ER+/PR±/HER2+ T+, not reached if N0 and 106mo if N+ (p 0.436); ER−/PR−/HER2+ T−, not reached if N0 and 34mo if N+ (p 0.273); ER−/PR−/HER2+ T+, not reached neither if N0 nor if N+ (p 0.094). Materials and Methods Disease-free survival (DFS) and overall survival (OS) were evaluated according to tumor characteristics, based on information retrospectively retrieved from patients’ medical records. Conclusions Pathological tumor characteristics and nodal status still represent useful tools in treatment selection and follow-up decision making of EBC patients in clinical practice.