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Kubicek, Gregory J

Publications and source records attributed to Kubicek, Gregory J.

Phase I Trial Using the Proteasome Inhibitor Bortezomib and Concurrent Chemoradiotherapy for Head-and-Neck Malignancies

Purpose: Advanced head-and-neck cancer (HNC) remains a difficult disease to cure. Proteasome inhibitors such as bortezomib have the potential to improve survival over chemoradiotherapy alone. This Phase I dose-escalation study examined the potential of bortezomib in combination with cisplatin chemotherapy and concurrent radiation in the treatment of locally advanced and recurrent HNC. Methods and Materials: Eligible patients received cisplatin once weekly at 30 mg/m{sup 2} per week and bortezomib along with concurrent radiation. Bortezomib was given on Days 1, 4, 8, and 11 every 3 weeks, with an initial starting dose of 0.7 mg/m{sup 2} and escalation levels of 1.0 and 1.3 mg/m{sup 2}. Dose escalation was performed only after assessment to rule out any dose-limiting toxicity. Results: We enrolled 27 patients with HNC, including 17 patients with recurrent disease who had received prior irradiation. Patients received bortezomib dose levels of 0.7 mg/m{sup 2} (7 patients), 1.0 mg/m{sup 2} (10 patients), and 1.3 mg/m{sup 2} (10 patients). No Grade 5 toxicities, 3 Grade 4 toxicities (all hematologic and considered dose-limiting toxicities), and 39 Grade 3 toxicities (in 20 patients) were observed. With a median follow-up of 7.4 months, the overall median survival was 24.7 months (48.4 months for advanced HNC patients and 15.4 months for recurrent HNC patients). Conclusion: Bortezomib in combination with radiation therapy and cisplatin chemotherapy is safe in the treatment of HNC with a bortezomib maximum tolerated dose of 1.0 mg/m{sup 2} in patients previously treated for HNC and 1.3 mg/m{sup 2} in radiation-naive patients.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

Do Elderly Patients Experience Increased Perioperative or Postoperative Morbidity or Mortality When Given Neoadjuvant Chemoradiation Before Esophagectomy?

Background: The use of induction chemoradiotherapy followed by surgery has been widely used for the treatment of esophageal cancer. The presumed risk of increased postoperative morbidity and mortality with this regimen has led to reluctance to offer this therapy to elderly patients. We compared the perioperative morbidity and mortality of patients 70 years old and older with those of patients younger than 70 who received CRT followed by esophagectomy and sought to identify preoperative risk factors that may predict higher risk of postoperative death or complications. Methods and Materials: We identified 260 patients who underwent preoperative chemoradiotherapy followed by esophagectomy. The association of age with postoperative death and complications was evaluated. The Charlson index, prior cardiac history, and diabetes were identified as preoperative risk factors and were evaluated as potential confounders or effect modifiers. Results: Cardiac disease and the Charlson index were potential modifiers of the effect of age on length of hospital stay (p = 0.08 and p = 0.07, respectively) and postoperative complications (p = 0.1 and p = 0.2) but were not statistically significant. There was a slight nonsignificant decrease in the risk of death in elderly patients after adjustment for the Charlson index (p = 0.2). Conclusion: No significant differences were detected with respect to morbidity and mortality in elderly patients. The presence of cardiac disease, higher scores on the Charlson index, or diabetes did not significantly influence length of stay, postoperative complications, or postoperative death. Given the potential to improve outcomes, this regimen should not be discounted in elderly patients.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

PSA Decrease During Combined-Modality Radiotherapy Predicts for Treatment Outcome

Purpose: Prostate-specific antigen (PSA) is the well-used marker in the diagnosis, prognosis, and follow-up for prostate cancer patients. Although reports have focused on the importance of pretreatment PSA levels, doubling time, and posttreatment nadirs, there is little information on the value of PSA during the course of radiotherapy. Methods and Materials: Retrospective review of PSA values obtained midway through a course of radiotherapy treatment for prostate cancer. Patients had a PSA (midPSA) measured after a course of external beam radiation (EBRT) before planned transperineal low-dose-rate brachytherapy implant (LDR). Results: A total of 717 patients were analyzed with a median follow-up of 5.8 years, all censored patients had a minimum follow-up of 2 years. A total of 277 patients had low-risk disease, 267 patients had intermediate risk, and 173 patients had high-risk disease. Androgen blockade was used in 512 patients. A total of 653 patients had a midPSA decrease after EBRT, the median decrease was 6.2 ng/mL. Patients who had a midPSA decrease {>=}25% compared with pretreatment PSA had improved overall survival of 10.0 vs. 7.4 years (p < 0.0004) and improved disease-free survival of 9.8 vs. 7.3 years (p < 0.01). When stratified by use of androgen blockade, midPSA remained significant for both androgen and non-androgen patients. Conclusions: PSA response after EBRT before brachytherapy predicts for long-term outcome; this may allow for risk stratification and intervention with higher LDR doses to improve outcomes.

62 RADIOLOGY AND NUCLEAR MEDICINE↗