A Phase I clinical trial of dose-escalated metabolic therapy combined with concomitant radiation therapy in high-grade glioma.

BACKGROUND: Animal brain-tumor models have demonstrated a synergistic interaction between radiation therapy and a ketogenic diet (KD). Metformin has in-vitro anti-cancer activity, through AMPK activation and mTOR inhibition. We hypothesized that the metabolic stress induced by a KD combined with metformin would enhance radiation's efficacy. We sought to assess the tolerability and feasibility of this approach. METHODS: A single-institution phase I clinical trial. Radiotherapy was either 60 or 35 Gy over 6 or 2 weeks, for newly diagnosed and recurrent gliomas, respectively. The dietary intervention consisted of a Modified Atkins Diet (ModAD) supplemented with medium chain triglycerides (MCT). There were three cohorts: Dietary intervention alone, and dietary intervention combined with low-dose or high-dose metformin; all patients received radiotherapy. Factors associated with blood ketone levels were investigated using a mixed-model analysis. RESULTS: A total of 13 patients were accrued, median age 61 years, of whom six had newly diagnosed and seven with recurrent disease. All completed radiation therapy; five patients stopped the metabolic intervention early. Metformin 850 mg three-times daily was poorly tolerated. There were no serious adverse events. Ketone levels were associated with dietary factors (ketogenic ratio, p < 0.001), use of metformin (p = 0. 02) and low insulin levels (p = 0.002). Median progression free survival was ten and four months for newly diagnosed and recurrent disease, respectively. CONCLUSIONS: The intervention was well tolerated. Higher serum ketone levels were associated with both dietary intake and metformin use. The recommended phase II dose is eight weeks of a ModAD combined with 850 mg metformin twice daily.

Gallium-68 prostate-specific membrane antigen PET-CT and the clinical management of prostate cancer.

OBJECTIVES: The purpose of this study was to evaluate the use of Gallium-68 prostatic-specific membrane antigen (PSMA) PET-computerized tomography (CT) in patients with prostate cancer undergoing imaging for initial staging, biochemical failure or the evaluation of metastatic disease. METHODS: This is a single institution retrospective study of 95 patients with prostate cancer who were referred for PSMA PET-CT scans. The National Comprehensive Cancer Network guidelines were used to generate treatment recommendations. Univariate and multivariate statistical analyses were performed to identify parameters associated with positive findings on a PET-CT PSMA scan. RESULTS: Mean age, Gleason score, and median prostate serum antigen (PSA) were: 72 years, 7.6 and 4 ng/ml, respectively. PSMA PET-CT was positive in 75.5% of the patients. A maximum standardized uptake value was 10.7 ± 8.8. PSMA avidity increased with rising PSA level: PSA ≤ 1 ng/ml: 5/15 patients (33%); PSA 1-5 ng/ml: 18/27 patients (67%), and PSA ≥ 5 ng/ml: 33/34 patients (97%). Following imaging in nine high-risk patients referred for staging, changes in treatment occurred in 6 (67%). Treatment recommendations changed in 27/35 (65%) patients referred due to biochemical failure; these included recurrences suitable for salvage therapy (n = 14), metastatic disease not suitable for salvage therapy (n = 10), and no lesion (n = 17). No changes in treatment occurred in any of the 35 patients referred to evaluate metastatic disease. DISCUSSION: PSMA PET-CT imaging may have a substantial impact on clinical management in prostate cancer patients at the time of initial staging or with biochemical failure; yet this modality does not appear useful in the management of patients with known metastatic disease.

Classifying high-risk versus very high-risk prostate cancer: is it relevant to outcomes of conformal radiotherapy and androgen deprivation?

OBJECTIVE: To evaluate outcomes in prostate cancer patients classified as high-risk (HR) or very high-risk (VHR) who were treated with conformal radiation therapy (CRT) and androgen deprivation therapy (ADT). METHODS: Between 11/2001 and 3/2012, 203 patients with HR disease received CRT to the prostate (78-82 Gy) and pelvic lymph nodes (46-50 Gy) with ADT (6 m-2 years). Median follow-up was 50 months (12 m-142 m). Biochemical failure was defined according to Phoenix definition. Imaging studies were used to identify local, regional or metastatic failure. Four different VHR/HR groupings were formed using the 2014 and revised 2015 NCCN guidelines. Differences were examined using Kaplan Meier (KM) estimates with log rank test and uni- and multivariate Cox regression analysis (MVA). RESULTS: Failure occurred in 30/203 patients (15%). Median time to failure was 30 m (4 m-76 m). KM estimate of 4 year biochemical disease free survival (b-DFS) for the entire cohort was 87% (95%CI: 82-92%). Four year KM survival estimates for b-DFS, PCSS and OS were comparable for each NCCN subgroup. On univariate analysis, the NCCN subgroups were not predictive of b-DFS at 4 years, however, DMFS was worse for both VHR subgroups (p = .03and .01) respectively. Cox univariate analysis was also significant for: PSA ≥40 ng/ml p = 0.001; clinical stages T2c p = .004, T3b p = .02 and > 4 cores with Gleason score 8-10 p < .03. On MVA, only PSA ≥ 40 ng/ml was predictive for b-DFS or MFS at 4 years (HR: 3.75 and 3.25, p < 0.005). CONCLUSION: Patients with HR and VHR disease treated with CRT and ADT had good outcomes. Stratification into HR and VHR sub-groups provided no predictive value. Only PSA ≥40 ng/ml predicted poor outcomes on MVA. Distant failure was dominant and local recurrence rare, suggesting that improved systemic treatment rather than intensification of local therapy is needed. Patients with high-risk prostate cancer are most often treated with conformal dose escalated radiation therapy with androgen deprivation. Stratification into high versus very high-risk subgroups using 2014 or revised 2015 National Comprehensive Cancer Network (NCCN) criteria did not impact treatment outcomes. Only Prostate Serum Antigen (PSA) ≥40 ng/ml was predictive of poor prognosis. Distant failure was dominant and local recurrence uncommon which challenges the notion that intensification of local therapy will further improve outcomes in patients with high-risk disease.

Adjuvant chemotherapy and whole abdominal irradiation for gastric carcinoma.

AIMS AND BACKGROUND: To analyze the efficacy and toxicity of adjuvant chemotherapy followed by whole abdominal irradiation in the treatment of resectable gastric cancer with positive lymph nodes. METHODS AND STUDY DESIGN: Between 1996 and 1999, 10 patients with node-positive gastric cancer underwent complete gross resection and were treated by postoperative chemoradiotherapy. The chemotherapy regimen consisted of 5-fluorouracil, 1000 mg/m2/day as a 96-hr continuous infusion on day 1, and cisplatin, 100 mg/m2 on day 2, every 21 days. Six courses were planned. Radiotherapy was administered 3 weeks after completion of the chemotherapy protocol as a single-fraction dose of 600 cGy in a two-field (anterior and posterior) configuration. RESULTS: Treatment was generally well tolerated, with no treatment-related deaths. However, 9 of the 10 patients died of recurrent disease, with a median survival of 20 months (range, 7-84). CONCLUSIONS: Adjuvant chemotherapy with whole abdominal irradiation for gastric cancer is safe and tolerable but has no apparent effect on patient outcome. Studies in larger series are needed to evaluate the role of the approach in this disease.

A phase II study of oral UFT and leucovorin concurrently with pelvic irradiation as neoadjuvant chemoradiation for rectal cancer.

BACKGROUND: Neoadjuvant chemoradiation with continuous infusion (CI) of 5-fluorouracil (5FU) is widely used in rectal cancer. The aim of this study was to evaluate the use of oral tegafur-uracil (UFT) and leucovorin (LV) instead of CI 5FU. PATIENTS AND METHODS: Patients had resectable T3-4 or low T2 rectal adenocarcinoma. Chemoradiation consisted of pelvic irradiation (45 Gy in fractions of 1.8 Gy) and oral UFT (240 mg/m2/day) and LV (30 mg/day) given during the first 28 days of radiotherapy. RESULTS: Thirty-two patients were treated; 81% had T3-4 tumors and 25% had N+ disease. Toxicity, predominantly gastrointestinal, was generally mild. Grade 3 toxicity occurred in only one patient. Pathological down-staging was noted in 13 patients (42%) and pathological complete response in 3 (10%). Sphincter preservation was possible in 71% of patients undergoing surgery. CONCLUSION: Neoadjuvant chemoradiation with oral UFT/LV is well-tolerated and active against rectal cancer. Formal comparison with the current standard treatment is warranted.