The impact of pretreatment prostate volume on severe acute genitourinary toxicity in prostate cancer patients treated with intensity-modulated radiation therapy.

PURPOSE: To assess the impact of pretreatment prostate volume on the development of severe acute genitourinary toxicity in patients undergoing intensity-modulated radiation therapy (IMRT) for prostate cancer. METHODS AND MATERIALS: Between 2004 and 2007, a consecutive sample of 214 patients who underwent IMRT (75.6 Gy) for prostate cancer at two referral centers was analyzed. Prostate volumes were obtained from computed tomography scans taken during treatment simulation. Genitourinary toxicity was defined using the National Cancer Institute Common Terminology Criteria for Adverse Events Version 3.0 guidelines. Acute toxicity was defined as any toxicity originating within 90 days of the completion of radiation therapy. Patients were characterized as having a small or large prostate depending on whether their prostate volume was less than or greater than 50 cm(3), respectively. Genitourinary toxicity was compared in these groups using the chi-square or Fisher's exact test, as appropriate. Bivariate and multivariate logistic regression analysis was performed to further assess the impact of prostate volume on severe (Grade 3) acute genitourinary toxicity. RESULTS: Patients with large prostates (>50 cm(3)) had a higher rate of acute Grade 3 genitourinary toxicity (p = .02). Prostate volume was predictive of the likelihood of developing acute Grade 3 genitourinary toxicity on bivariate (p = .004) and multivariate (p = .006) logistic regression. Every 27.0 cm(3) increase in prostate volume doubled the likelihood of acute Grade 3 genitourinary toxicity. CONCLUSIONS: Patients with larger prostates are at higher risk for the development of severe acute genitourinary toxicity when treated with IMRT for prostate cancer.

Radical prostatectomy vs. intensity-modulated radiation therapy in the management of localized prostate adenocarcinoma.

BACKGROUND AND PURPOSE: To determine whether radical prostatectomy (RP) or intensity-modulated radiation therapy (IMRT) to > or =72 Gy, plus hormonal therapy if indicated, results in improved biochemical disease-free survival (BDFS) in localized prostate adenocarcinoma. MATERIALS AND METHODS: Between 1997 and 2005, a consecutive sample of 556 patients who underwent RP (n=204) or IMRT (n=352) at two referral centers was analyzed. The patients were stratified into prognostic groups based on clinical stage, Gleason score, and pretreatment prostate-specific antigen (PSA). The outcome measure was BDFS. RESULTS: IMRT patients had more advanced disease at baseline (p<.001). There was no difference in five-year BDFS rates between RP and IMRT in the favorable (92.8% vs. 85.3%, p=.20) or intermediate prognosis (86.7% vs. 82.2%, p=.46) subsets. A difference favoring IMRT plus hormonal therapy was seen in the poor prognosis (38.4% vs. 62.2%, p<.001) subset. Within the entire cohort, after adjustment for confounding variables, Gleason score (p<.001) and clinical stage (p<.001) predicted BDFS, but treatment modality (p=.06) did not. Within the poor prognosis subset, treatment modality (p=.006) predicted BDFS. CONCLUSIONS: BDFS is similar between RP and IMRT for patients with a favorable or intermediate prognosis. Patients with a poor prognosis display higher BDFS when treated with IMRT to > or =72 Gy plus hormonal therapy.

Whole pelvic radiotherapy versus prostate only radiotherapy in the management of locally advanced or aggressive prostate adenocarcinoma.

PURPOSE: To determine whether whole pelvic radiotherapy (WPRT) or prostate-only radiotherapy (PORT) yields improved biochemical disease-free survival (BDFS) in patients with advanced or aggressive prostate adenocarcinoma. METHODS AND MATERIALS: Between 2000 and 2007, a consecutive sample of 277 patients with prostate adenocarcinoma and at least a 15% likelihood of lymph node involvement who had undergone WPRT (n = 68) or PORT (n = 209) at two referral centers was analyzed. The median radiation dose in both arms was 75.6 Gy. The outcome measure was BDFS, as determined using the prostate-specific antigen nadir + 2 ng/mL definition of failure. BDFS was calculated using the Kaplan-Meier method and compared with the log-rank test. A multivariate analysis was performed to assess for confounding. Treatment-related toxicity was assessed using the National Cancer Institute's Common Terminology Criteria for Adverse Events guidelines. The median follow-up was 30 months. RESULTS: WPRT patients had more advanced and aggressive disease at baseline (p < .001). The 4-year BDFS rate was 69.4% in the PORT cohort and 86.3% in the WPRT cohort (p = .02). Within the entire cohort, after adjustment for confounding variables, the pretreatment prostate-specific antigen (p < .001), Gleason score (p < .001), use of hormonal therapy (p = .002), and use of WPRT (vs. PORT, p = .006) predicted for BDFS. Patients undergoing WPRT had increased acute gastrointestinal toxicity (p = .048), but no significant difference in acute genitourinary toxicity was seen (p = .09). No difference in late toxicity was found. CONCLUSION: WPRT may yield improved BDFS in patients with advanced or aggressive prostate adenocarcinoma, but results in a greater incidence of acute toxicity.

A phase II study of topotecan and cyclophosphamide with G-CSF in patients with advanced small cell lung cancer.

PURPOSE: We conducted a multicenter phase II study to evaluate the efficacy and safety of the combination of topotecan and cyclophosphamide for patients with advanced small cell lung cancer (SCLC). PATIENTS AND METHODS: Patients were eligible if they had newly diagnosed extensive stage SCLC or if they had SCLC that progressed more than three months after completion of the first chemotherapy regimen. Patients were treated every 21 days with cyclophosphamide 600 mg/m2 IV on day 1 and topotecan 1.0 mg/m2 on days 1 to 5. Filgrastim was administered for 10 days starting on day 6. Patients were evaluated for objective tumor response, time to tumor progression, overall survival and toxicity. RESULTS: Forty-two eligible patients were treated. Seventeen patients (40.5%) had an objective response including 4 (9.5%) complete remissions (CR). Fifteen patients (35.7%) had stable disease. There are 2 patients known to be alive at the time of this report: one with stable disease at 26 months and another with a CR at 37 months. The median number of cycles completed was 6 (range 1-12). The major toxicities were grades 3 and 4 neutropenia (73.8%), grades 3 and 4 anemia (35.7%) and grades 3 and 4 thrombocytopenia (50%). Five patients died during the first cycle of chemotherapy. The median time to progression was 3 months (range 5 days-36 months) (CI: 51-135 days) and the median overall survival was 9 months (5 days-37 months) (CI: 210-330 days). The two-year survival rate was 21%. CONCLUSIONS: The combination of topotecan and cyclophosphamide is highly active in small cell lung cancer. Myelosuppression is the major toxicity and is rapidly reversible in most patients. The incidence of treatment-related mortality was comparable to some other intensive chemotherapy regimens. This incidence is unacceptably high and indicates better selection criteria are needed in order to exclude patients at excessive risk of morbidity.

Phase I study of perillyl alcohol in patients with refractory malignancies.

We treated 21 patients in a dose-finding and pharmacokinetic study of the monoterpene perillyl alcohol with the drug given orally in 3 divided doses on a chronic basis. The average number of days that patients remained on study was 48 (range 11-172). Fatigue and low-grade nausea were dose limiting. Using this schedule, a starting dose of 1.6 g/m2 with escalation to 2.1 g/m2 as tolerated is recommended. Two major metabolites were detectable and the mean peak plasma concentrations were 383 microM for perillic acid and 27 microM for dihydroperillic acid. The peak plasma concentration and the metabolite half-life were 2 h and 1 h post ingestion for perillic acid, and 4 h and 2.4 h for dihydroperillic acid, respectively. Stabilization of disease was observed in one of the 16 patients evaluable for response. Many of the gastrointestinal side effects that were poorly tolerated on a chronic basis may be partly related to the soybean oil base used in the current formulation. Further development of perillyl alcohol on this schedule would be facilitated by reformulation of the capsule.

Phase I dose escalation trial of weekly docetaxel plus irinotecan in patients with advanced cancer.

Background. Docetaxel and irinotecan have additive or synergistic activity in vitro and in vivo as well as differing toxicities and unique mechanisms of action. We conducted a phase I trial to determine the maximum-tolerated dose of docetaxel and irinotecan given on a weekly schedule. Methods. Eligible patients had advanced, incurable, solid tumors. Docetaxel was administered as a 1-hour infusion and escalated over four dose levels (25, 30, 35, and 40 mg/m(2)) followed by irinotecan administered over 30 minutes at a fixed dose of 50 mg/m(2). Treatment was administered weekly for four weeks followed by two weeks of rest. To improve tolerability, the schedule was modified to weekly administration for two weeks with one week of rest, and irinotecan was escalated over 3 dose levels (55, 60, and 65 mg/m(2)) with docetaxel fixed at 35 mg/m(2). Results. Forty-four patients were treated and the most common dose-limiting toxicity was diarrhea observed in 11% of patients. Severe neutropenia was rare (grade 4: 2%, grade 3: 23%). Other nonhematologic toxicities included nausea/vomiting, dehydration and fatigue. Partial responses occurred in two patients with pancreatic cancer, and one patient each with non-small cell lung and esophageal cancer. Conclusions. Weekly docetaxel and irinotecan is a promising non-cisplatin doublet with preliminary evidence of activity in advanced solid tumors. Diarrhea is the predominant dose-limiting toxicity but unlike the every 3 weeks schedule myelosuppression is modest. The recommended phase II doses are docetaxel 35 mg/m(2) and irinotecan 60 mg/m(2) on days 1 and 8 of a 21-day schedule. Phase II trials of this regimen are ongoing or planned in lung, head and neck, stomach, esophageal, and pancreatic cancers.