From adjuvant to preventive breast cancer treatment: bridging the gap over troubled waters.

Recently, chemoprevention trials have demonstrated the efficacy of preventive medical treatment (PMT) in reducing breast cancer (BC) detection rates in at-risk affected and unaffected women selected according to clinical and/or familial risk criteria, particularly with the use of tamoxifen (TAM). Major concerns limiting the routine use of TAM are the questionable benefit/risk ratio and poor patient compliance, which justify the studies undertaken to determine the efficacy of aromatase inhibitors (AIs) with respect to TAM. Issues such as therapy duration, impact on survival, incidence of side-effects and which subsets benefit most from treatment, still remain unsolved. Therefore, only ER+ BC patients are routinely subjected to PMT, independently of their BRCA1/2 status, using adjuvant hormonal therapy. More attention must be focused towards BRCA1/2 carriers as they are probably the women at highest risk of developing BC, in which available data remain controversial and in which hormone-therapy might be important. Hence, at-risk women (affected patients or unaffected women) should be carefully evaluated for inclusion into highly selected preventive clinical trials aimed at evaluating PMT independently of, or according to, BC predisposition status (unknown, positive or negative BRCA1/BRCA2 status) and with respect to menopausal status. BC patients, harboring a BRCA1/2 predisposition, may represent the best subset for extended adjuvant treatment, useful as PMT, simultaneously. Only the evolving differentiation of categories of at-risk women will allow physicians to discriminate PMT in a highly selective manner.

Novel P53 mutations detected by FAMA in colorectal cancers.

BACKGROUND: The aim of the study was to identify p53 gene mutations by FAMA (fluorescence-assisted mismatch analysis) in colorectal cancers. PATIENTS AND METHODS: Analytical scanning of the p53 gene (exons 5-9) was performed in colon cancer samples from 44 consecutive patients by FAMA. FAMA is a semiautomatic scanning approach based on the chemical cleavage of the mismatch in fluorescently labeled heteroduplex DNA, obtained from the combination of a normal and a mutated allele. FAMA has already shown optimal levels of diagnostic accuracy and sensitivity in detecting gene mutations (nucleotide substitutions, insertions/deletions) both at the germline and somatic level. The peculiar feature of FAMA is its ability to detect and localize mutations, by a redundant pattern of signals due to fluorescent DNA fragments generated by chemical cleavage. Moreover, previous data have demonstrated that normal contaminating DNA from stromal cells in the sample does not affect the sensitivity of the procedure, leading to the identification of the mutation even when the ratio mutant/normal allele is 10%. RESULTS: Eighteen mutations (12 missense, one nonsense, two deletions, three nucleotide substitutions at the level of the splice-junctions) and two polymorphisms were detected by FAMA in 17 patients (39%) and then confirmed by automated sequence analysis. Six of 18 mutations (33%) were not previously reported for colon cancer samples and two of 18 lesions (11%) were identified as novel p53 mutations. CONCLUSIONS: Analytical scanning of the p53 gene by FAMA in DNA from colon cancer samples provides a sensitive, accurate and specific diagnostic procedure for routine clinical application.

Increased tolerability of bimonthly 12-hour timed flat infusion 5-fluorouracil/irinotecan regimen in advanced colorectal cancer: A dose-finding study.

A dose-finding study was designed to determine the maximum tolerated dose (MTD) of a bimonthly 12-h (10:00 p.m to 10:00 a.m), timed flat infusion (TFI) of 5-fluorouracil (5-FU) plus irinotecan (CPT-11), without leucovorin (LV), for metastatic colorectal carcinoma (CRC). A total of 33 patients were treated. Seven dose levels included a fixed CPT-11 dose of 180 mg/m2 on days 1 and 15 (d(1,15)) and escalating doses of 5-FU 600-1200 mg/m2 on days 1-4 and 15-18 (d(1-4,15-18)). Dose-limiting toxicities (DLTs) were: grade 3-4 non-hematologic, grade 4 hematologic and any toxicity causing a more than a 2-week delay in treatment. The MTD was reached at the seventh dose level. DLTs were observed in 5/8 patients (63%): G3 diarrhea, 2 patients, associated with G3 mucositis in one instance; G4 neutropenia, 2 patients, associated with severe asthenia in 1 patient; G3 hand-foot syndrome, 1 patient. The recommended doses (RDs) were established at the sixth dose level: 5-FU, 1100 mg/m2/d(1-4,15-18); CPT-11 180 mg/m2/d(1,15) [5-FU and CPT-11 dose intensity (DI), 2200 and 90 mg/m2 per week (w), respectively]. At the recommended dose, the DLTs in 38 cycles were: mucositis, 2 cycles (5%); afebrile G4 neutropenia and hand-foot syndrome, 1 cycle (3%). In 24 assessable patients, the overall response rate was 37.5%. The present CPT-11/5-FU schedule is highly tolerable in an outpatient setting using the highest recommended 5-FU dose effective in advanced CRC.

Timed flat infusion of 5-fluorouracil increases the tolerability of 5-fluorouracil/docetaxel regimen in metastatic breast cancer: a dose-finding study.

A dose-finding study was undertaken to determine the maximum-tolerated dose, and the recommended dose of docetaxel in combination with 12-h timed (22:00-10:00) flat infusion of 5-fluorouracil (5-FU) in metastatic breast cancer patients. This schedule seems to reduce the occurrence of stomatitis of the docetaxel and infusional 5-FU regimen.

[Can analysis of the molecular status of the p53 gene contribute to improving the therapeutic strategy for breast carcinoma?]. / L'analisi dello stato molecolare del gene p53 può contribuire ad innovare le strategie terapeutiche nel carcinoma della mammella?

The occurrence of mutations in the p53 tumor suppressor gene is a specific and recurring genetic event in solid tumors. P53 plays a pivotal role in multiple cellular processes such as cell growth control, DNA repair and programmed cell death. Genotoxic damage, also induced by chemotherapy or radiotherapy, induces p53 overexpression in order to control the rate of proliferating damaged cells, thus triggering the mismatch repair or apoptotic pathways. P53 inactivation determines a condition of genetic instability, justifying the subsequent susceptibility to acquire mutations of different other genes. P53 mutations are associated with worse prognosis and with chemo/radioresistance, due to the inability to trigger p53-dependent programmed cell death. Molecular diagnostic strategies show 32% p53 mutations in breast cancer. The analysis of the p53 gene performed by FAMA (Fluorescence Assisted Mismatch Analysis) in high-risk breast cancer patients with > or = 10 involved axillary nodes may help identify a subset of very high risk BC patients (vHR-BC) with poorer prognosis and a subset with better prognosis, potentially responsive to medical treatments. The accurate evaluation of the p53 status can predict prognosis and sensitivity to chemotherapy, thus representing the first step toward better definition of therapeutic strategies according to the molecular characterization of the individual patient.

Prophylactic options in patients with 5-fluorouracil-associated cardiotoxicity.

At present, the various mechanisms involved in 5-fluorouracil (5-FU)-correlated cardiotoxicity remain to be elucidated and a universally accepted prophylaxis or treatment for this specific toxicity is not available. Although it may improve time to progression, survival and clinical benefit, a 5-FU-based regimen usually has to be discontinued if a patient experiences cardiotoxicity. Here, we describe our experience with three cases of 5-FU-associated cardiotoxicity. The angina-like pain that appeared approximately 95 h after beginning 5-FU therapy was apparently independent of the drug's administration modality. In the two patients receiving 5-FU 12-h flat continuous infusion from 22.00 to 10.00 h (5-FU 12-h c.i.) in combination with other drugs, the dose of 5-FU was reduced by 10-20% and patients received prophylactic transepidermal nitroglycerin. In the third patient, 5-FU administration modality was changed and prophylactic therapy was not given. By taking these precautions, the patients no longer complained of anginal pain and none of them discontinued chemotherapy.

Prognostic value of p53 molecular status in high-risk primary breast cancer.

BACKGROUND: Mutations in the p53 gene are the most common genetic alterations in human primary breast carcinoma and these mutations are often associated with worse prognosis and chemo/radioresistance. PATIENTS AND METHODS: The analysis of the p53 gene was performed by fluorescence-assisted mismatch analysis in 13 consecutive high-risk primary breast cancer (HR-BC) patients with 10 or more involved axillary nodes to evaluate its prognostic value. RESULTS: Three p53 mutations (23%) and four allelic variants were detected. After a median follow-up of 52 months the HR-BC disease-free survival (DFS) was 51% and overall survival 79%. All patients harboring a p53 mutation (p53(mut)) relapsed within 10 months of the median DFS while 67% of those showing a wild-type p53 status (p53(wt)) survive disease-free at a median follow-up of 43 months. One p53(mut) patient is still alive while all the p53(wt) patients survive at 56 months median follow-up. Two out of the four p53(wt) relapsing breast cancer patients showed the Arg72Pro allelic variant; one of these died at 75 months. CONCLUSIONS: p53 mutations may help identify a subset of very high risk breast cancer patients (vHR-BC) with worse prognosis.