Detection of a possible case of pulmonary tumour thromboembolism by endobronchial ultrasound

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Expression of breast cancer resistance protein (BCRP) in esophageal cancers (EC)

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Background: EC patients face a dismal outcome despite tri-modality management strategy. Median survival remains 15–18 months despite platinum, fluropyrimidine & irinotecan based therapy. BCRP is an ATP-dependent efflux protein associated with chemotherapy (CT) (e.g. irinotecan) resistance. Role of BCRP expression in EC and normal esophageal cells is not known. We examined the expression of this protein and correlate it with survival (OS) in patients receiving irinotecan-based CT. Methods: With IRB approval, 40 cases of EC diagnosed between 2004 and 2008 were stained for BCRP expression by IHC & scored by the pathologist blinded to clinical data. Baseline demographics, therapy given & OS data were collected and correlated with BCRP expression. BCRP score (membrane or cytoplasm) >/= 30 was considered positive (calculated by multiplying BCRP intensity and % staining). Fisher's exact test used to determine association between BCRP expression & demographics. Cox proportional hazards model used for association of BCRP & OS. Results: Baseline patient and tumor characteristics: Gender: M 35, F 5; Histology: 37 Adenoca & 3 SCC; Stage 1-III 27, Stage IV 10, unknown 3; CT: cisplatin+irinotecan (n=16), oxaliplatin+fluoropyrimidine (n=8), other (n=16); IHC: 30 of 40 cancers (75%) expressed BCRP [strong (n=28) & intermediate (n=3); membranous (n=17), cytoplasmic (n=27) & both (n=14)]. Down-regulation of BCRP expression in tumor compared to normal cells seen in 40% of patients. Median OS was 19 months with no difference in OS between BCRP positive and negative patients (p=0.13). Estimated hazard ratio (HR) of death for BCRP positive patients was 2.29 (95% CI 0.79 - 6.64).There was no association between BCRP expression and stage, age, gender or histology. For patients who received cisplatin and irinotecan as first line CT there was no difference in OS (p=0.39) of BCRP negative versus positive patients. Conclusions: BCRP expression is seen in a majority of EC & normal esophageal mucosa. Response rates to irinotecan based therapies are seen in 30–40 % of EC, whether the 40% with low tumor BCRP constitute a majority of the responders needs to be prospectively validated in a larger dataset & should include markers that predict response to 5-FU & platinum based CT to allow individualizing therapy for this cancer.

No significant financial relationships to disclose.

S-phase modulation by irinotecan: pilot studies in advanced solid tumors

Two studies of irinotecan (CPT-11) followed 24 h later by an antimetabolite were conducted. The objectives of the studies were: (1) to determine whether the increase in S-phase in tumor cells seen 24 h after CPT-11 administration in animal studies is seen in advanced solid tumors in patients, (2) to determine the dose of CPT-11 required to produce this effect, (3) to compare two methods (immunohistochemistry, IHC, for cyclin A, and DNA flow cytometry, FC) for evaluating S-phase in tumor biopsies from patients, and (4) to establish the maximum tolerated dose (MTD) and dose-limiting toxicity (DLT) of CPT-11, given 24 h before gemcitabine (GEM, 1000 mg/m(2)). In one study CPT-11 was followed 24 h later by 5-fluorouracil (5-FU), 400 mg/m(2) per week for 4 weeks every 6 weeks. Tumor biopsies were obtained before and 24 h after CPT-11 administration before administration of 5-FU and assayed for S-phase by IHC for cyclin A and by FC. The starting dose of CPT-11 was 80 mg/m(2) per week with subsequent exploration of 40 and 60 mg/m(2) per week to establish the dose-effect relationship of the increase in tumor cells in S-phase. In the second study, CPT-11 was given 24 h before GEM 1000 mg/m(2) per week for 2 weeks every 3 weeks. Doses of 20-80 mg/m(2) were explored to establish the MTD and DLT and to study tumor cell S-phase in selected patients. CPT-11 80 mg/m(2) produced a mean increase in S-phase by IHC for cyclin A of 137%. Lesser increases were seen with 40 and 60 mg/m(2). CPT-11 followed 24 h later by 5-FU 400 mg/m(2) per week for 4 weeks was well tolerated. In the study of CPT-11 followed by GEM 1000 mg/m(2), 60 mg/m(2) of CPT-11 was the MTD.