Samer Alsidawi

Expression of PD-1 and PD-L1 in anaplastic thyroid cancer patients treated with multimodal therapy: Results from a retrospective study

Context Anaplastic thyroid cancer (ATC) is rare and a highly fatal malignancy. The role of programmed death-1 (PD-1) and programmed death ligand-1 (PD-L1) as prognostic and/or predictive markers in ATC is unknown. Objective Multimodal therapy offers the best chance at tumor control. The objective of this study was to detect potential associations of PD-1/PD-L1 axis variables with outcome data in ATC. Design Retrospective study of a uniformly treated cohort. Setting Single institution retrospective cohort study. Patients or Other Participants Sixteen patients who received intensity-modulated radiation therapy (15 had preceding surgery) were studied. Main Outcome Measure Patients treated with multimodal therapy were followed and assessed for overall survival (OS) and progression-free survival (PFS). Results All samples demonstrated PD-1 expression in inflammatory cells whereas tumor cells were primarily negative. PD-L1 was expressed on ATC tumor cells in most samples and showed mainly membranous staining. High PD-1 expression (>40% staining) in inflammatory cells was associated with worse overall survival (OS; hazard ratio, 3.36; 95% confidence interval, 1.00 to 12.96; P < 0.05) and trended toward worse PFS, whereas high PD-L1 expression in tumor cells (>33% staining) trended toward worse PFS and OS. Conclusion PD-1/PD-L1 pathway proteins are highly expressed in ATC tumor samples and appear to represent predictive markers of PFS and OS in multimodality-treated ATC patients.

Characteristics and long-term outcomes of head and neck squamous cell carcinoma after solid organ transplantation

INTRODUCTION Immunosuppression after solid organ transplant prevents graft rejection, but leads to increased incidence of various malignancies including head and neck squamous cell carcinoma (HNSCC). Outcomes of patients with post-transplant HNSCC are unknown. MATERIALS AND METHODS We retrospectively identified patients who developed HNSCC after solid organ transplant between 1995 and 2010. Adults with pathology-proven HNSCC and adequate follow up were included. Median overall survival and progression free survival were analyzed using the Kaplan-Meier method. The prognostic effect of variables was studied with Cox proportional hazards models. RESULTS Thirty-three patients met study inclusion criteria. The median time to diagnosis of HNSCC after transplant was 5.9years. The primary site was oral cavity in 15 patients, oropharynx in 10, larynx in 3, hypopharynx in 2, parotid in 2 and unknown in 1 patient. Eighty-eight percent underwent upfront surgical resection. Of those, sixty-six percent received adjuvant therapy. Six percent of patients had definitive chemoradiation. Treatment was well tolerated and did not lead to graft rejection. The 5-year overall survival rate was 45% and 37% for localized and locally advanced disease respectively. Seventy-five percent of patients with oropharyngeal tumors were HPV-positive and they had better outcomes (5-year overall survival rate of 67%). In multivariate analysis, age ≥60years was a negative predictor of survival (HR 2.7; 95% CI, 1.1-6.5; P=0.03). CONCLUSIONS Patients with post-transplant HNSCC have relatively poor survival and high risk of locoregional and distant recurrence. HPV- positive oropharyngeal tumors continue to have better outcomes in this population.