Systemic toxicities of trastuzumab-emtansine predict tumor response in HER2+ metastatic breast cancer.

The mechanism by which trastuzumab-emtansine (T-DM1) causes systemic toxicities apart from trastuzumab alone is currently unknown. We hypothesized that the systemic toxicities from T-DM1 may have been caused by the free and active maytansine released from the lysed HER2+ tumor cells, and if so, they may correlate with the response to treatment and eventually disease-free survival or patient outcome. In a retrospective, observational study, we evaluated 73 patients from three centers in the United States and Canada with advanced HER2+ breast cancer that received at least one dose of T-DM1. Toxicity grades were summed to create a corresponding toxicity sum score (TSS), and its association with clinical outcomes was analyzed. A higher TSS was significantly associated with longer progression-free survival with an HR = 0.66 [95% confidence interval [CI]: 0.47-0.92], P = .014, for each 1-point increase in the TSS score. Adjusted for baseline platelet count, aspartate transaminase and alanine transaminase, higher TSS remains significantly associated with longer progression-free survival with adjusted HR = 0.67 [95% CI: 0.47-0.93], P = .020. The analysis suggests that the systemic toxicities of T-DM1 were significantly correlated with its clinical efficacy. This is the first report to correlate the systemic toxicities of T-DM1 with clinical outcome. Further, this suggests that systemic toxicities of antibody-drug conjugates (ADCs) may serve as a predictive biomarker, particularly if noncleavable linkers are used. If confirmed in larger prospective studies, the present finding is significant because most ADCs do not have a biomarker predictive of clinical outcome other than the presence or absence of the antibody target.

Small Biopsies Misclassify up to 35% of PD-L1 Assessments in Advanced Lung Non-Small Cell Lung Carcinomas.

Pembrolizumab is an FDA-approved immune-checkpoint (IC) inhibitor that targets programmed cell death protein PD-1, and recent phase III trials have demonstrated its superiority over chemotherapy in the treatment of patients with advanced non-small cell lung cancer (NSCLC). Eligibility for treatment with Pembrolizumab is based on demonstration of PD-L1 expression on tumoral cells using the approved companion test 22C3 PharmDx (Dako). Access to the drug depends on a tumor proportion score (TPS) expressing the PD-L1 protein above predetermined cutoffs. The scoring interpretation guide requires a minimum of 100 viable cells to be considered adequate for evaluation. Recent studies have questioned the adequacy of the sampling process when small biopsies are utilized. To further explore this concern, the viable tumor area of 426 consecutive NSCLC biopsies and surgical excisions submitted for PD-L1 assessment was measured and recorded with corresponding PD-L1 expression. About 14.6% of all biopsies measured <2 mm creating 2 groups (<2 mm and ≥2 mm) whose PD-L1 categories distribution [negative (<1%), low expressor (≥1% and <50%), and positive (≥50%)] were compared. Results were significantly different between both groups (χ test; P=0.0012). To help understand this difference, 1,407,000 in silico simulated biopsies of various sizes were performed on 201 numerical tumors created from digitalized full sections and analyzed. Not only the same results shown in actual biopsies were reproduced, but the model calculated that up to 35% of very small biopsies were misclassified including a mixture of false negative and false positive results. The percentage decreased to 10% with a threshold of 5 mm. In era of precision medicine, appropriate sampling is more than ever critical to achieve accurate assessment of the NSCLC PD-L1. Ignored in most clinical trials, recording of biopsy size would permit refining data analysis and increase predictive accuracy of current and future biomarkers.

Detergent: an alternative approach to traditional bone cleaning methods for forensic practice.

Osteological assessment of human remains forms an essential part of forensic work, especially during the examination of extensively decomposed, dismembered, or burnt bodies. Currently employed methods for removal of adherent soft tissue reflect practices often used by museum curators, notably insect consumption, enzymatic maceration, or boiling of the bones, with subsequent manual removal of material. This study was designed to assess the effectiveness of detergents for the purpose of soft-tissue removal from animal-derived specimens. The results indicate that such a means is comparable to enzymatic maceration but with fewer health and safety issues and greater advantages regarding transportation and availability of materials when an investigator is in a fieldwork scenario.