Is Radiation-Induced Cardiac Toxicity Reversible? Prospective Evaluation of Patients With Breast Cancer Enrolled in a Phase 3 Randomized Controlled Trial.

PURPOSE: Myocardial perfusion defects after breast radiation therapy (RT) correlate with volume of irradiated left ventricle (LV). We aimed to determine the relationship between myocardial perfusion, LV dosimetry, and grade ≥2 late cardiac events in patients with breast cancer undergoing adjuvant RT. METHODS AND MATERIALS: A randomized study evaluated the benefit of inverse-planned intensity modulated radiation therapy over forward-planned intensity modulated radiation therapy for radiation toxicity in breast cancer. A secondary endpoint was evaluating cardiac perfusion by single-photon emission computed tomography done at baseline, 6 months, 1 year, 2 years, and 5 years post-RT. We used receiver operating curve and regression analysis to identify association between perfusion, radiation dose-volumes, and the risk of late cardiac events. RESULTS: Of 181 patients who received adjuvant RT, 102 were patients with cancer in the left breast (called in this study the left-sided group) and 79 were patients with cancer in the right breast (called in this study the right-sided group). Median follow-up was 127 months (range, 19-160 months). A significant worsening of perfusion defects occurred after RT in the left-sided group, which improved by 1 year. Late cardiac events were found among 16 patients (17.2%) in the left-sided group and 4 patients (5.5%) in the right-sided group. Perfusion changes did not correlate with late cardiac events, but LV dose-volumes correlated with late cardiac events. Maintaining the LV volume receiving 5 Gy and 10 Gy to <42 cc and <38cc, respectively, can reduce the risk of radiation-related late cardiac events at 10 years to <5% over baseline. CONCLUSIONS: RT was associated with short-term perfusion defects that improved within 1 year and was not correlated with late cardiac events. The ventricular volumes receiving 5 Gy and 10 Gy were correlated with late cardiac events.

PSMA Theranostics: Current Landscape and Future Outlook.

INTRODUCTION: Prostate-specific membrane antigen (PSMA) is a promising novel molecular target for imaging diagnostics and therapeutics (theranostics). There has been a growing body of evidence supporting PSMA theranostics approaches in optimizing the management of prostate cancer and potentially altering its natural history. METHODS: We utilized PubMed and Google Scholar for published studies, and clinicaltrials.gov for planned, ongoing, and completed clinical trials in PSMA theranostics as of June 2021. We presented evolving evidence for various PSMA-targeted radiopharmaceutical agents in the treatment paradigm for prostate cancer, as well as combination treatment strategies with other targeted therapy and immunotherapy. We highlighted the emerging evidence of PSMA and fluorodeoxyglucose (FDG) PET/CT as a predictive biomarker for PSMA radioligand therapy. We identified seven ongoing clinical trials in oligometastatic-directed therapy using PSMA PET imaging. We also presented a schematic overview of 17 key PSMA theranostic clinical trials throughout the various stages of prostate cancer. CONCLUSIONS: In this review, we presented the contemporary and future landscape of theranostic applications in prostate cancer with a focus on PSMA ligands. As PSMA theranostics will soon become the standard of care for the management of prostate cancer, we underscore the importance of integrating nuclear medicine physicians into the multidisciplinary team.

Erlotinib monotherapy in patients with advanced non-small cell lung cancer: an effective approach with low toxicity.

BACKGROUND: Treatment of non-small cell lung cancer (NSCLC) with tyrosine kinase inhibitors (TKIs) of epidermal growth factor receptor (EGFR) and particularly erlotinib (Tarceva) has been a field of intense research. This retrospective study was conducted to assess the efficacy of erlotinib and its impact on survival. PATIENTS AND METHODS: Patients with stage IIIB or IV, advanced or recurrent metastatic NSCLC were included in the study and were administered erlotinib 150 mg daily, at different lines of treatment. RESULTS: Thirty-six patients were included in the study: 29 (81%) male, 7 (19%) female. At the time of analysis, all patients had progressed and died. Median progression-free survival (PFS) was 4 months +/- 2.43 months (range 0-8 months), whereas median overall survival (OS) was 7 months +/- 2.65 months (range 3-15 months). Patients with ECOG performance status of 0 or 1 had better OS and significantly higher PFS rates. Overall response rate was 16.7%, while the disease control rate was 81%. CONCLUSION: Erlotinib is effective and well tolerated in pretreated patients with advanced NSCLC and a good performance status.