Citations

Purpose Patient adherence is critical in evaluating the effectiveness of an oral therapy. We sought to measure adherence among women randomly assigned to capecitabine in a preplanned substudy of a multicenter clinical trial. Patients and Methods Cancer and Leukemia Group B study CALGB 49907 was a randomly assigned trial comparing standard chemotherapy versus oral chemotherapy with capecitabine in patients age 65 years or older with early-stage breast cancer. We used microelectronic monitoring system (MEMS) caps on participants' capecitabine bottles to record pill bottle openings. Capecitabine was given in two divided daily doses for 14 consecutive days of a 21-day cycle for six cycles. Adherence was calculated as the number of doses taken divided by doses expected, taking into account toxicity-related dosing changes. A participant was defined as adherent if 80% or more of expected doses were recorded by MEMS. Results Overall, 161 patients were enrolled. Median age was 71 years (range, 65 to 89 years); 124 patients (83%) persisted with capecitabine to completion of planned protocol therapy. Adherence was 78% across all cycles, and adherence did not vary by cycle (P = .32). Twenty-five percent of participants took fewer than 80% of expected doses and were nonadherent. In a logistic regression model, participants with node-negative disease (P = .01) and mastectomy (P = .01) were more likely to be nonadherent. Adherence was not related to age, tumor stage, or hormone receptor status. Adherence was not significantly associated with relapse-free survival or grade 3 or 4 toxicity. Conclusion Most older women with early-stage breast cancer were adherent to short-term oral chemotherapy in a randomized clinical trial. Age was not associated with adherence.

Abstract Recent studies have indicated that neutral collagenase can be produced in bones of rats. In addition, it has been demonstrated by in vitro studies that the enzyme is likely secreted by osteoblasts. Cells of the osteoblastic tumor cell line UMR-106 can be stimulated to produce not only collagenase, but also collagenase inhibitor and plasminogen activator. However, it is conceivable that not all osteoblasts produce all of these proteins. In this study, in which UMR cells were maximally stimulated with PTH, only a subpopulation of cells was observed to produce enhanced levels of collagenase but all cells had the ability to synthesize plasminogen activator. Cells of the rat osteosarcoma line UMR-106-01 were stained for the presence of collagenase and tissue plasminogen activator using an immunohistochemical procedure. In many cases, the cells were exposed to monensin for the final 3 h of incubation as well as to the inducing agent PTH. Monensin prevented export of the enzymes, enabling them to be visualized within their cell of origin. Maximal stimulation of collagenase was demonstrated to occur 8 h after exposure to 10−8-10−7 M PTH. Under these conditions, 14-17% of the cells appeared to synthesize elevated amounts of collagenase (as determined by intense staining). Without PTH stimulation, there was a low level of collagenase in all cells, but < 1% of the cells stained heavily for the enzyme. In contrast, strong staining for plasminogen activator was observed in all cells with or without PTH treatment. This suggests that the regulation of collagenase production in osteoblasts occurs at the level of the individual cell such that there appear to be subpopulations of cells that respond differently to PTH stimulation.