Clinical Outcomes in Two Different Cohorts of Patients with Inflammatory Breast Cancer (IBC) Treated at the MD Anderson Cancer Center: The Experience of the Morgan Welch IBC Research Program and Clinic

BACKGROUND: Inflammatory Breast Cancer (IBC) is a rare but aggressive manifestation of primary breast cancer. Survival in patients with IBC is significantly lower than for non-IBC breast cancer patients. Appropriate diagnostic and treatment strategies provided by a specialized multidisciplinary team could impact the overall prognosis of the disease. We recently established an IBC research program and clinic including investigators from various disciplines solely dedicated to this disease. We sought to compare the characteristics and clinical outcomes of newly diagnosed IBC patients evaluated and treated using novel diagnostic and therapeutic approaches with an historical cohort of IBC patients treated at our institution.METHODS: We included 240 IBC patients treated at MD Anderson Cancer Center between January 1970 and August 2000. In this analysis we compared characteristics, 1 year progression free survival (PFS) and 1 year survival between the historic cohort and 47 patients diagnosed with IBC and seen at our IBC clinic between August 2007 and September 2008. The new patients are part of a prospective IBC registry. All of them had staging and monitoring with breast MRI and FDG-PET/CT. When indicated, they were treated with targeted therapies (e.g. trastuzumab and tipifarnib), that were not available for the patients in the old cohort. Descriptive statistics were used. Kaplan Meier product-limit method was used to calculate survival outcomes, groups were compare by log-rank test.RESULTS: Median age was similar in both cohorts (53 vs 51). In the new cohort 40% of the patients had evidence of distant metastasis at presentation. The most common sites were contralateral lymph nodes (26%), pleura (16%), bone (16%) and liver (11%). In the old cohort only 17% presented with stage IV. 38.7% of the new patients had Her2-neu amplified and 34%, triple receptor negative IBC. There was no difference in 1-year survival between the two groups (92.4% vs. 93.8%, p=0.637). For patients with stage III disease, the 1-year survival was 95% for both groups. The 1 year-PFS was 86.4% in the new cohort compared to 77.9% (p=0.43) in the old cohort. With a median follow up of 13 months, 51%of the patients in the new cohort are disease free and 87% are still alive.CONCLUSIONS: IBC is an aggressive but rare disease with poor prognosis. We have established a specialized IBC research program and clinic that introduces novel concepts and strategies in laboratory, imaging diagnostics and targeted therapies. This approach may accelerate our understanding of the biology, develop new therapeutic strategies and finally improve the outcome of IBC. Early results of this multidisciplinary approach show a modest, but not significant difference in outcome. We hope that with additional patients and longer follow-up a significant improvement in outcomes will become apparent.

Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 5119.

Thomboembolic Events in Patients with Breast Cancer: A Population Based Study

BACKGROUND: Thromboembolic events (TEEs) are common in patients with cancer. Metastatic disease, treatment and comorbidities have been associated with increased risk. In this population-based study we sought to evaluate the risk factors and the prevalence of different TEEs in patients with breast cancer.METHODS: Retrospective cohort study using the SEER-Medicare linked database. Patients with breast cancer (stage I-IV) diagnosed from 1992-2002, who were 66 and older, and had full coverage of Medicare A and B were identified. ICD-9, HCPCS codes were used to identify different TEEs that occurred within one year of the breast cancer diagnosis. We identified pulmonary embolism (PE), deep venous thrombosis (DVT)/thrombophlebitis, other TEEs, as well as the use of chemotherapy, radiotherapy, surgery and comorbidities. Analyses were conducted using descriptive statistics and logistic regression.RESULTS: 71,864 patients were included. Age groups were distributed as follows: 66-70 (24.1%), 71-75 (26.4%), 76-80 (23.2%), >80 (26.3%). At diagnosis 52.4% of patients had stage I, 35.2% stage II, 6.6% stage III and 5.8% stage IV. 66.8% of the patients had ER-positive breast cancer. Within one year of diagnosis, 2652 (3.7%) of patients developed a TEE, including 800 patients with at least two events. 3565 total number of events were observed. A total of 596 (0.85%) PEs, 1252 (1.74%) DVT/thrombophlebitis, and 1717 (3.39%) other TEEs were identified. In the univariate analysis race, marital status, education and poverty level, geographical location, stage, tumor grade, estrogen receptor status, comorbidities, as well as surgical modality, radiation therapy and chemotherapy use, were associated with the development of any TEE.After adjusting for potential confounders, the development of any TEE was associated with ER-positive tumors (OR 1.20, 95% CI 1.07-1.34), stage II vs. I (OR 1.22, 95% CI 1.11-1.35), stage III vs. I (OR 1.63, 95% CI 1.40-1.90), stage IV vs. I (OR 2.16, 95% CI 1.82-2.57), chemotherapy (OR 2.02, 95% CI 1.82-2.23), radiotherapy (OR 1.39, 95% CI 1.27-1.52), comorbidity score (OR 1.19, 95% CI 1.08-1.32 and OR 1.74, 95% CI 1.54-1.96 for score 1 and 2 respectively), and type of surgery (OR 1.25, 95% CI 1,13-1.38 for mastectomy vs. breast conservation surgery and OR 1.23, 95% CI 1.02-1.49 for no surgery vs. breast conservation surgery). Borderline association was seen with age (using 66-70 as a reference value, the ORs for the 71-75, 76-80 and >80 year old categories were: 1.14, 95%CI 1.02-1.28; 1.17, 95% CI 1.04-1.32; and 1.15, 95% CI 1.01-1.29 respectively). Relatively similar estimates were seen for the analysis of PE, DVT/thrombophlebitis and other TEEs.CONCLUSION: 3.7% of patients in this cohort developed a TEE within one year from breast cancer diagnosis. Age, stage, type of treatment, comorbidities and receptor status were associated with the development of TEEs. To the best of our knowledge this is the largest cohort of patients older than 66years old, in which the patterns and risk factors associated with TEEs are analyzed. Whether these observations apply to patients younger than age 65, remains to be established.

Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 2053.

Fosfomycin prevents cisplatin-induced ototoxicity: Results of a randomized, double blind, placebo controlled trial

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Background: Cisplatin is one of the most frequently used chemotherapy agents. The main dose-limiting toxicity for its use is hearing-loss, present in 40–100% of patients. To date, no treatment has proven efficacy in preventing or reducing cisplatin acoustic damage. Fosfomycin, acting as a free-radical scavanger, has shown to reduce cisplatin-induced ototoxicity and nephrotoxicity in animal models, without affecting its antineoplastic activity. This trial evaluated the effect of fosfomycin in cisplatin-induced ototoxicity. Methods: 22 chemotherapy naive patients with normal audition, scheduled to receive cisplatin-based chemotherapy (cumulative dose =200mg/m2) were randomized to receive placebo (n=11) or 1g of IV fosfomycin concurrent with each cisplatin administration (2–4 cycles). Primary outcome was ototoxicity when comparing audiometric studies (low and high frequencies and otoaccustic emissions) at baseline and at completion of chemotherapy. With β=0.8 and a=0.05 the study was powered to detect differences =20 dB at any given frequency. Fisher's test, Wilcoxon and Mann-Whitney test were used. Results: Groups were balanced for baseline characteristics, cisplatin dose and response rates. No differences were found when comparing ototoxicity at low frequency ranges. When analyzing high frequencies and otoaccustic emissions, 9 patients (82%) in the placebo group developed ototoxicity vs 4 (36%) in the fosfomycin group (p=0.04). The degree of hearing-loss, evaluated by comparing percentage of change in each evaluated frequency, was significantly lower in patients receiving fosfomycin (p=0.04). Other chemotherapy toxicities were similar in both groups. Conclusions: In patients with audiometric integrity, the concurrent administration of fosfomycin with cisplatin significantly reduces ototoxicity. The degree of hearing-loss is lower in patients receiving fosfomycin than in those receiving placebo. The use of fosfomycin in combination with cisplatin is safe and does not interfere with its antineoplastic activity. To our knowledge this is the first clinical-trial that demonstrates prevention and reduction of cisplatin-induced hearing-loss.

No significant financial relationships to disclose.