Incorporating weekly carboplatin in anthracycline and paclitaxel-containing neoadjuvant chemotherapy for triple-negative breast cancer: propensity-score matching analysis and TIL evaluation.

BACKGROUND: The generation of data capturing the risk-benefit ratio of incorporating carboplatin (Cb) to neoadjuvant chemotherapy (NACT) for triple-negative breast cancer (TNBC) in a clinical practice setting is urgently needed. Tumour-infiltrating lymphocytes (TILs) have an established role in TNBC receiving NACT, however, the role of TIL dynamics under NACT exposure in patients receiving the current standard of care is largely uncharted. METHODS: Consecutive TNBC patients receiving anthracycline-taxane [A-T] +/- Cb NACT at three Institutions were enrolled. Stromal-TILs were evaluated on pre-NACT and residual disease (RD) specimens. In the clinical cohort, propensity-score-matching was used to control selection bias. RESULTS: In total, 247 patients were included (A-T = 40.5%, A-TCb = 59.5%). After propensity-score-matching, pCR was significantly higher for A-TCb vs A-T (51.9% vs 34.2%, multivariate: OR = 2.40, P = 0.01). No differences in grade ≥3 haematological toxicities were observed. TILs increased from baseline to RD in the overall population and across A-T/A-TCb subgroups. TIL increase from baseline to RD was positively and independently associated with distant disease-free survival (multivariate: HR = 0.43, P = 0.05). CONCLUSIONS: We confirmed in a clinical practice setting of TNBC patients receiving A-T NACT that the incorporation of weekly Cb significantly improved pCR. In addition, A-T +/- Cb enhanced immune infiltration from baseline to RD. Finally, we reported a positive independent prognostic role of TIL increase after NACT exposure.

Outcomes of Radiotherapy in Oligoprogressive Breast Cancer.

INTRODUCTION: Radiotherapy (RT) shows potential for improving local control in cases of oligoprogressive metastatic breast cancer (mBC). This retrospective analysis aims to evaluate the advantages of RT in such a clinical scenario. METHODS: We conducted a retrospective analysis including patients with mBC who received radiation therapy (RT) for up to three sites of oligoprogression while continuing systemic therapy. The study took place between January 2014 and December 2021. Our endpoints were progression-free survival after radiotherapy (PFS-AR), the rate of discontinuation of systemic therapy (RDT) at three months post-RT, and overall survival (OS). We used Cox regression analysis to perform multivariate analysis for PFS-AR. RESULTS: Fifty-nine patients met the inclusion criteria. The PFS-AR was 13 months (95% CI 8.5-18.8 months). At three months, the RDT was 3% (two patients). A significant difference in median PFS-AR was observed between patients in the first + second-line group and those in the subsequent line group (p = 0.03). In the multivariate analysis conducted for PFS-AR, the biologically effective dose (BED) with α/ß = 4 > 100 Gy emerged as the sole significant variable (p = 0.0017). The median overall survival (OS) was 24.4 months (95% CI 17-24.4 months). CONCLUSIONS: This study is the first report on the outcomes of radiotherapy in a cohort of over 50 patients with oligoprogressive metastatic breast cancer (mBC). Our findings emphasize the significant relationship between PFS-AR, the number of ongoing lines of systemic therapy, and the BED of radiotherapy.

The likelihood of being helped or harmed as a patient-centred tool to assess cyclin dependent kinase 4/6 inhibitors clinical impact and safety in metastatic breast cancer: a systematic review and sensitivity-analysis.

Background: In hormone-receptor positive/HER2-negative metastatic breast cancer (mBC) no randomized comparisons are available between CDK4/6 inhibitors. We undertook this systematic review and meta-analysis to assess the reliability of the likelihood of being helped or harmed (LHH). Methods: PubMed, CENTRAL, Embase and oncological meetings websites were searched to September 13th, 2022. We included phase III randomized controlled trials (RCTs) investigating palbociclib, ribociclib and abemaciclib in addition to endocrine therapy (ET) compared to placebo in hormone-receptor positive/HER2-negative advanced or mBC. Outcomes were progression-free survival (PFS), overall survival (OS), adverse events (AEs), dose reductions and discontinuations. Hazard ratios (HRs) and risk differences were computed with a random effect model to estimate the number needed to treat/harm (NNT/NNH). LHH was computed as (1/NNT)/(1/NNH). PROSPERO registration number: CRD42022362417. Findings: 2204 records were screened and seven RCTs (4415 patients) were included. A significant PFS benefit was observed in patients treated with a CDK4/6 inhibitor compared to placebo (HR 0.549; 0.508-0.594, I 2  = 0). Palbociclib, ribociclib and abemaciclib had similar NNTs (4.4, 5.0 and 4.4). Palbociclib and ribociclib showed lower LHHs for grade 3-4 neutropenia (0.33 and 0.35) and febrile neutropenia ([FN], 14.27 and 15.52), while abemaciclib the lowest LHH for any grade diarrhea (0.42). Abemaciclib had a lower LHH for grade 3-4 fatigue (9.92) and the highest LHH for all grade 3-4 AEs (0.62), while ribociclib the lowest LHH (1.75) for grade 3-4 hepatotoxicity. Palbociclib had the highest LHH for dose reductions and discontinuations (0.65 and 6.17). Considering OS, an overall benefit was observed (HR 0.788, 0.727-0.856, I 2  = 0%); ribociclib and abemaciclib had lower NNTs (9.7 and 10.0). Ribociclib showed the highest LHH for diarrhea (1.29), fatigue (7.37), dose reductions (0.28) and discontinuations (2.40), while abemaciclib the highest LHHs for neutropenia (0.40), FN (12.53) and hepatotoxicity (2.23). Interpretation: Palbociclib and ribociclib showed lower LHHs for haematological toxicities and abemaciclib for diarrhea. Palbociclib confirmed to be a manageable drug. The LHH appears to be a reliable synthesis tool for balancing risks and benefits of experimental drugs when head-to-head comparisons are missing. Funding: None.

Estrogen deprivation effects of endocrine therapy in breast cancer patients: Incidence, management and outcome.

Endocrine therapy is one of the standard adjuvant treatments to reduce the risk of recurrence and mortality in patients with hormone receptor positive early breast cancer. Despite its proven efficacy, ET side effects, which persist over time even if low grade, may deteriorate quality of life. During follow-up visits, emphasis is generally placed on the risk of disease recurrence, while the topic of ET side effects is commonly neglected and discussed only briefly. This could lead to poor adherence to therapy and early treatment discontinuation, resulting in worse survival outcomes. The aim of this review is to provide an overview of the available evidence on the incidence and reporting of ET-related side effects (including vasomotor symptoms, musculoskeletal disorders and genitourinary syndrome of menopause, as well as fatigue, psychological and ocular disorders, dysmetabolic effects and loss of bone density) and of the pharmacological and non-pharmacological strategies available to mitigate symptom burden.

Case report: Vitiligo-like toxicity due to ribociclib during first-line treatment of metastatic breast cancer: two cases of premature interruption of therapy and exceptional response.

Cancer treatment-related adverse events (AEs) are sometimes associated with outcomes for cancer patients, especially with the newest therapies such as target therapy and immunotherapy. A few years ago, the first-line therapy for hormone-receptor-positive metastatic breast cancer (mBC) patients has been deeply changed by the introduction of cyclin-dependent kinase (CDK) 4/6 inhibitors, and now, we are improving our knowledge about their AEs and significance in clinical practice. Here, we report our experience with two cases of vitiligo-like lesions that occur early during treatment with ribociclib. We tried to change the CDK4/6 inhibitor for one patient, but the skin reaction persisted. Both patients retained only the endocrine therapy alone and had an unexpected durable progression-free survival (PFS). Some data on skin toxicities, including vitiligo-like lesions by CDK4/6 inhibitors, have recently been reported in the literature, but for the first time, we highlight a possible correlation with improved survival outcomes of patients. Uncovering the etiology of this toxicity, verifying the involvement of the immune system, and demonstrating a possible positive impact in survival represent an intriguing research objective for the near future.

Adjuvant denosumab in early breast cancer: a systematic review and meta-analysis of randomized controlled clinical trials.

Background: In early breast cancer (BC) the impact of denosumab on survival outcomes is still unclear. We undertook a systematic review and meta-analysis to assess efficacy and safety of adjuvant denosumab in addition to standard anticancer therapy. Methods: PubMed, CENTRAL, Scopus, Embase, and oncological meetings websites were screened to identify potentially eligible randomized controlled trials (RCTs). Survival outcomes were disease-free survival (DFS), bone-metastasis-free survival (BMFS), and overall survival (OS). Fracture incidence and time to first fracture were bone-health outcomes. Osteonecrosis of the jaw (ONJ), atypical femur fractures (AFF), and other adverse events were also evaluated. Pooled hazard ratios (HRs) and risk ratios (RR) with respective 95% confidence interval (95% CI) were computed using a random-effects model. Exploratory subgroup analyses were performed. Results: Two phase III RCTs were included, the Austrian Breast & Colorectal Cancer Study Group-18 (ABCSG-18) and the D-CARE trials, for a total of 7929 patients. In the ABCSG-18 trial, denosumab was administered every 6 months during endocrine therapy (for a median of seven cycles) while the D-CARE trial used an intensive schedule for a total treatment duration of 5 years. Adjuvant denosumab showed no difference in DFS (HR: 0.932; 95% CI: 0.748-1.162), BMFS (HR: 0.9896; 95% CI: 0.751-1.070), and OS (HR: 0.917; 95% CI: 0.718-1.171) compared to placebo in the overall population. In hormone receptor positive/human epidermal growth factor receptor 2 (HER2) negative BC patients, a DFS (HR: 0.883; 95% CI: 0.782-0.996) and BMFS (HR: 0.832; 95% CI: 0.714-0.970) benefit was observed and BMFS was prolonged in all hormone receptor positive patients (HR: 0.850; 95% CI: 0.735-0.983). Fracture incidence (RR: 0.787; 95% CI: 0.696-0.890) and time to first fracture (HR: 0.760; 95% CI: 0.665-0.869) were also improved. No increase in overall toxicity was seen with denosumab and no differences were observed for ONJ and AFF between the 60-mg every 6-month schedule and placebo. Conclusion: Denosumab addition to anticancer treatment does not improve DFS, BMFS, or OS in the overall population, although a DFS improvement was observed in hormone receptor positive/HER2 negative BC patients and a BMFS improvement in all hormone receptor positive patients. Bone-health outcomes were improved with no added toxicity with the 60-mg schedule. Registration: PROSPERO identifier: CRD42022332787.

Development of a nomogram for predicting pathological complete response in luminal breast cancer patients following neoadjuvant chemotherapy.

Background: Given the low chance of response to neoadjuvant chemotherapy (NACT) in luminal breast cancer (LBC), the identification of predictive factors of pathological complete response (pCR) represents a challenge. A multicenter retrospective analysis was performed to develop and validate a predictive nomogram for pCR, based on pre-treatment clinicopathological features. Methods: Clinicopathological data from stage I-III LBC patients undergone NACT and surgery were retrospectively collected. Descriptive statistics was adopted. A multivariate model was used to identify independent predictors of pCR. The obtained log-odds ratios (ORs) were adopted to derive weighting factors for the predictive nomogram. The receiver operating characteristic analysis was applied to determine the nomogram accuracy. The model was internally and externally validated. Results: In the training set, data from 539 patients were gathered: pCR rate was 11.3% [95% confidence interval (CI): 8.6-13.9] (luminal A-like: 5.3%, 95% CI: 1.5-9.1, and luminal B-like: 13.1%, 95% CI: 9.8-13.4). The optimal Ki67 cutoff to predict pCR was 44% (area under the curve (AUC): 0.69; p < 0.001). Clinical stage I-II (OR: 3.67, 95% CI: 1.75-7.71, p = 0.001), Ki67 ⩾44% (OR: 3.00, 95% CI: 1.59-5.65, p = 0.001), and progesterone receptor (PR) <1% (OR: 2.49, 95% CI: 1.15-5.38, p = 0.019) were independent predictors of pCR, with high replication rates at internal validation (100%, 98%, and 87%, respectively). According to the nomogram, the probability of pCR ranged from 3.4% for clinical stage III, PR > 1%, and Ki67 <44% to 53.3% for clinical stage I-II, PR < 1%, and Ki67 ⩾44% (accuracy: AUC, 0.73; p < 0.0001). In the validation set (248 patients), the predictive performance of the model was confirmed (AUC: 0.7; p < 0.0001). Conclusion: The combination of commonly available clinicopathological pre-NACT factors allows to develop a nomogram which appears to reliably predict pCR in LBC.

Updated Neoadjuvant Treatment Landscape for Early Triple Negative Breast Cancer: Immunotherapy, Potential Predictive Biomarkers, and Novel Agents.

Triple-negative breast cancer (TNBC) is characterized by the absence of hormone receptor and HER2 expression, and therefore a lack of therapeutic targets. Anthracyclines and taxane-based neoadjuvant chemotherapy have historically been the cornerstone of treatment of early TNBC. However, genomic and transcriptomic analyses have suggested that TNBCs include various subtypes, characterized by peculiar genomic drivers and potential therapeutic targets. Therefore, several efforts have been made to expand the therapeutic landscape of early TNBC, leading to the introduction of platinum and immunomodulatory agents into the neoadjuvant setting. This review provides a comprehensive overview of the currently available evidence regarding platinum agents and immune-checkpoint-inhibitors for the neoadjuvant treatment of TNBC, as well as the novel target therapies that are currently being evaluated in this setting. Taking into account the economic issues and the side effects of the expanding therapeutic options, we focus on the potential efficacy biomarkers of the emerging therapies, in order to select the best therapeutic strategy for each specific patient.

Tailoring neoadjuvant treatment of HR-positive/HER2-negative breast cancers: Which role for gene expression assays?

Neoadjuvant chemotherapy (NACT) for breast cancer (BC) increases surgical and conservative surgery chances. However, a significant proportion of patients will not be eligible for conservative surgery following NACT because of large tumor size and/or low chemosensitivity, especially for hormone receptor (HR)-positive/ human epidermal growth factor receptor 2 (HER2)-negative tumors, for which pathological complete response rates are lower than for other BC subtypes. On the other hand, for luminal BC neoadjuvant endocrine therapy could represent a valid alternative. Several gene expression assays have been introduced into clinical practice in last decades, in order to define prognosis more accurately than clinico-pathological features alone and to predict the benefit of adjuvant treatments. A series of studies have demonstrated the feasibility of using core needle biopsy for gene expression risk testing, finding a high concordance rate in the risk result between biopsy sample and surgical samples. Based on these premises, recent efforts have focused on the utility of gene expression signatures to guide therapeutic decisions even in the neoadjuvant setting. Several prospective and retrospective studies have investigated the correlation between gene expression risk score from core needle biopsy before neoadjuvant therapy and the likelihood of 1) clinical and pathological response to neoadjuvant chemotherapy and endocrine therapy, 2) conservative surgery after neoadjuvant chemotherapy and endocrine therapy, and 3) survival following neoadjuvant chemotherapy and endocrine therapy. The purpose of this review is to provide an overview of the potential clinical utility of the main commercially available gene expression panels (Oncotype DX, MammaPrint, EndoPredict, Prosigna/PAM50 and Breast Cancer Index) in the neoadjuvant setting, in order to better inform decision making for luminal BC beyond the exclusive contribution of clinico-pathological features.

The Therapeutic Challenge of Disseminated Bone Marrow Metastasis From HR-Positive HER2-Negative Breast Cancer: Case Report and Review of the Literature.

The efficacy and safety of the combination of endocrine therapy (ET) and CDK4/6 inhibitors for patients with hormone receptor (HR)-positive HER2-negative metastatic breast cancer (BC) presenting with visceral crisis or life-threatening conditions represent a challenge for daily clinical practice. Indeed, the peculiarity of this clinical presentation (signs and symptoms of rapidly progressive disease) does not allow to include such patients in a trial aiming for drug approval. On the basis of the scientific evidence available so far, chemotherapy represents the standard of care according to guidelines, on the basis of the more rapid activity in comparison with ET alone. Besides, the combination of ET and CDK4/6 inhibitors have demonstrated in clinical trials to have clinically impactful activity in a short time, thus suggesting a potential role in advanced tumors that require rapid response. Herein, we report the clinical history of a young woman with HR-positive HER2-negative metastatic BC and a pancytopenia due to carcinomatosis of the bone marrow receiving letrozole and leuprorelin plus the CDK4/6 inhibitor palbociclib, who significantly derived clinical benefit from treatment. Considering that these peculiar cases are excluded from clinical trials, the estimation of the magnitude of the benefit of the newer ET combination may potentially represent a practical question for large case series and real-world studies.

Impact on survival of primary tumor resection in patients with metastatic breast cancer: preliminary results of a retrospective analysis.

BACKGROUND: Treatment of de-novo metastatic breast cancer is usually centered around systemic therapy, with local therapy (surgery and radiation therapy) largely reserved for palliation in patients with significant symptoms from primary tumor. The efficacy of locoregional treatment like surgery and/or radiotherapy is still controversial and the debate about surgical resection of primary tumor (PT) in de novo metastatic breast cancer (MBC) patients persists. METHODS: All patients with de-novo MBC undergone surgical treatment between January 2015 and January 2020 at the Multidisciplinary Breast Center of the IRCCS A. Gemelli University Polyclinic Foundation in Rome were included in this study. The primary endpoint was overall survival (OS) after PT resection, the secondary endpoint was progression free survival (PFS). The survival analyses were done using Kaplan-Meier method. Patients and tumor characteristics were analyzed in an exploratory modality in order to identify prognostic factor. RESULTS: Forty-five patients received resection of the primary breast cancer (26 mastectomy and 19 breast conserving surgery). Median age of diagnosis was 53 years old (range 25-75 years old). Median follow-up was 25.67 months. The median OS was not reached with 75% of patients alive over 2 years from PT resection. The median PFS was not reached with 64% of patients alive over 2 years from PT resection. For both PFS and OS only the triple negative (TN) immunophenotype appears to be a prognostically unfavorable factor in multivariate analysis. CONCLUSIONS: In view of the low number of disease progression events and deaths, although our results are preliminary, surgical treatment of primary breast cancer in metastatic setting seems to be an option after systemic therapies in luminal and HER2 positive breast cancer. Randomized prospective trials for each immunophenotype are necessary in order to confirm this evidence.

Liver Metastasectomy for Metastatic Breast Cancer Patients: A Single Institution Retrospective Analysis.

The liver represents the first metastatic site in 5-12% of metastatic breast cancer (MBC) cases. In absence of reliable evidence, liver metastasectomy (LM) could represent a possible therapeutic option for selected MBC patients (patients) in clinical practice. A retrospective analysis including MBC patients who had undergone an LM after a multidisciplinary Tumor Board discussion at the Hepatobiliary Surgery Unit of Fondazione Policlinico Universitario "Agostino Gemelli" IRCCS in Rome, between January 1994 and December 2019 was conducted. The primary endpoint was overall survival (OS) after a MBC-LM; the secondary endpoint was the disease-free interval (DFI) after surgery. Forty-nine MBC patients underwent LM, but clinical data were only available for 22 patients. After a median follow-up of 71 months, median OS and DFI were 67 months (95% CI 45-103) and 15 months (95% CI 11-46), respectively. At univariate analysis, the presence of a negative resection margin (R0) was the only factor that statistically significantly influenced OS (78 months versus 16 months; HR 0.083, p < 0.0001) and DFI (16 months versus 5 months; HR 0.17, p = 0.0058). A LM for MBC might represent a therapeutic option for selected patients. The radical nature of the surgical procedure performed in a high-flow center and after a multidisciplinary discussion appears essential for this therapeutic option.

Neoadjuvant therapy for triple-negative breast cancer: potential predictive biomarkers of activity and efficacy of platinum chemotherapy, PARP- and immune-checkpoint-inhibitors.

INTRODUCTION: Despite recent advances in the molecular characterization of triple-negative breast cancer (TNBC), the standard treatment for early-stage TNBC is represented by the historically used anthracycline and taxane-based chemotherapy. In this modern era of precision medicine, several new therapeutic strategies and novel agents have been investigated in the neoadjuvant setting of TNBC, in order to individualize treatment. AREAS COVERED: This review provides a comprehensive overview of the currently available evidence regarding the activity and efficacy of platinum agents, PARP- and immune-checkpoint-inhibitors for the neoadjuvant treatment of TNBC, highlighting the available data on potential predictive biomarkers of response or resistance to such treatments. EXPERT OPINION: The genomic and immune landscape of TNBC has encouraged the exploration of drugs that interfere with the DNA repair mechanism and that modulate immune response. Overall, these drugs seem to improve the pCR rate in TNBC, despite preliminary and heterogeneous results. Taking into account the economic issues and the side effects of these drugs, it is crucial to further explore the potential predictive role of BRCA mutational status and homologous recombination deficiency score, for platinum agents and PARP-inhibitors, and tumor infiltrating lymphocytes and other immune biomarkers for checkpoint inhibitors, respectively.

Treatment of Locally Advanced Gastric Cancer (LAGC): Back to Lauren's Classification in Pan-Cancer Analysis Era?

Background: Guidelines recommend a perioperative approach in patients with stage II/III gastric cancer, but in real-life many patients receive immediate surgery followed by adjuvant chemotherapy (aCT). Although histologic subtypes may have different response to CT, no study has explored the influence of histotype on the efficacy of perioperative CT (pCT) or aCT. Materials and methods: The objective of the study was to evaluate the impact of clinicopathological features and histology (intestinal or diffuse) on survival according to strategy (pCT vs. aCT). The primary endpoint was overall survival (OS) and the secondary endpoint was event-free survival (EFS). Results: Out of 203 patients affected by LAGC, 83 received pCT and 120 aCT. At multivariate, histology and LVI in pCT cohort and positive resection margin in the aCT influenced both OS and EFS. No difference in EFS and OS was observed in relation to strategy. However, in the intestinal-type of pCT cohort survival outcomes were significantly higher compared to the aCT cohort, whereas in the diffuse-type were significantly worse in patients receiving pCT compared to those receiving aCT. Conclusions: Although retrospective and small-sized, this study suggests that the benefit of pCT might be limited to the intestinal-type. This hypothesis needs to be confirmed in prospective series.

Palbociclib Plus Fulvestrant or Everolimus Plus Exemestane for Pretreated Advanced Breast Cancer with Lobular Histotype in ER+/HER2- Patients: A Propensity Score-Matched Analysis of a Multicenter Retrospective Patient Series.

Cyclin-dependent kinase 4/6 inhibitors (CDK4/6i) in combination with endocrine therapy (ET) show meaningful efficacy and tolerability in patients with metastatic breast cancer (MBC), but the optimal sequence of ET has not been established. It is not clear if patients with lobular breast carcinomas (LBC) derive the same benefits when receiving second line CDK4/6i. This retrospective study compared the efficacy of palbociclib plus fulvestrant (PALBO-FUL) with everolimus plus exemestane (EVE-EXE) as second-line ET for hormone-resistant metastatic LBC. From 2013 to 2018, patients with metastatic LBC positivity for estrogen and/or progesterone receptors and HER2/neu negativity, who had relapsed during adjuvant hormonal therapy or first-line hormonal treatment, were enrolled from six centers in Italy in this retrospective study. A total of 74 out of 376 patients (48 treated with PALBO-FUL and 26 with EVE-EXE) with metastatic LBC were eligible for inclusion. Progression-free survival (PFS) was longer in patients receiving EVE-EXE compared with PALBO-FUL (6.1 vs. 4.5 months, univariate HR 0.58, 95% CI 0.35-0.96; p = 0.025). On the propensity score (PS) analysis, PFS was confirmed to be significantly longer for patients treated with EVE-EXE compared to PALBO-FUL (6.0 vs. 4.6 months, p = 0.04). This retrospective analysis suggests that EVE-EXE is more effective than PALBO-FUL for second line ET of metastatic LBC, allowing us to speculate on the optimal therapeutic sequence.

Monoinstitutional real world experience in management of Vinflunine as second line therapy for transitional cell carcinoma of the urothelium.

Vinflunine is the only cytotoxic agent tested as a second line therapy in transitional cell carcinoma of the urothelium in a phase III trial. It is not largely employed in clinical practice because of the high incidence of grade 3-4 toxicity. We evaluated efficacy and safety of Vinflunine at the dose of 280 mg/m2 every 3 weeks associated with primary prophylaxis with granulocyte growth factors and laxatives for patients progressed after platinum + Gemcitabine. Overall survival was 8.5 months, progression-free survival 4.33 months and response rate 25%, with disease control rate 57.2%. Grade III-IV neutropenia occurred in 10.7% of the patients, grade III-IV anemia and grade III thrombocytopenia in 10.7% and 7.2%, respectively. Among non haematological toxicity, grade I-II constipation was reported in 14.2% of the patients, without grade III-IV adverse events. No discontinuation for toxicity was observed. This study underlines that Vinfluinine at a dose of 280 mg/m2 associated with primary prophylaxis for neutropenia and constipation is effective and with a favorable toxicity profile.