Context Among patients with locally advanced metastatic pancreatic adenocarcinoma, gemcitabine has been shown to improve outcomes compared with fluorouracil. Objective To determine if the addition of gemcitabine to adjuvant fluorouracil chemoradiation (chemotherapy plus radiation) improves survival for patients with resected pancreatic adenocarcinoma. Design, Setting, and Participants Randomized controlled phase 3 trial of patients with complete gross total resection of pancreatic adenocarcinoma and no prior radiation or chemotherapy enrolled between July 1998 and July 2002 with follow-up through August 18, 2006, at 164 US and Canadian institutions. Intervention Chemotherapy with either fluorouracil (continuous infusion of 250 mg/m 2 per day; n=230) or gemcitabine (30-minute infusion of 1000 mg/m 2 once per week; n=221) for 3 weeks prior to chemoradiation therapy and for 12 weeks after chemoradiation therapy. Chemoradiation with a continuous infusion of fluorouracil (250 mg/m 2 per day) was the same for all patients (50.4 Gy). Main Outcome Measures Survival for all patients and survival for patients with pancreatic head tumors were the primary end points. Secondary end points included toxicity. Results A total of 451 patients were randomized, eligible, and analyzable. Patients with pancreatic head tumors (n=388) had a median survival of 20.5 months and a 3-year survival of 31% in the gemcitabine group vs a median survival of 16.9 months and a 3-year survival of 22% in the fluorouracil group (hazard ratio, 0.82 [95% confidence interval, 0.65-1.03]; P=.09). The treatment effect was strengthened on multivariate analysis (hazard ratio, 0.80 [95% confidence interval, 0.63-1.00]; P=.05). Grade 4 hematologic toxicity was 1% in the fluorouracil group and 14% in the gemcitabine group (PϽ.001) without a difference in febrile neutropenia or infection. There were no differences in the ability to complete chemotherapy or radiation therapy (Ͼ85%). Conclusions The addition of gemcitabine to adjuvant fluorouracil-based chemoradiation was associated with a survival benefit for patients with resected pancreatic cancer, although this improvement was not statistically significant. Trial Registration clinicaltrials.gov Identifier: NCT00003216
In this study we evaluate the influences of optical property assumptions on near-infrared diffuse correlation spectroscopy (DCS) flow index measurements. The optical properties, absorption coefficient (µa) and reduced scattering coefficient (µs′), are independently varied using liquid phantoms and measured concurrently with the flow index using a hybrid optical system combining a dual-wavelength DCS flow device with a commercial frequency-domain tissue-oximeter. DCS flow indices are calculated at two wavelengths (785 and 830 nm) using measured µa and µs′ or assumed constant µa and µs′. Inaccurate µs′ assumptions resulted in much greater flow index errors than inaccurate µa. Underestimated/overestimated µs′ from −35%/+175% lead to flow index errors of +110%/−80%, whereas underestimated/overestimated µa from −40%/+150% lead to −20%/+40%, regardless of the wavelengths used. Examination of a clinical study involving human head and neck tumors indicates up to +280% flow index errors resulted from inter-patient optical property variations. These findings suggest that studies involving significant µa and µs′ changes should concurrently measure flow index and optical properties for accurate extraction of blood flow information.
Purpose Treatment of oropharyngeal squamous cell carcinoma (OPSCC) is evolving toward risk-based modification of therapeutic intensity, which requires patient-specific estimates of overall survival (OS) and progression-free survival (PFS). Methods To develop and validate nomograms for OS and PFS, we used a derivation cohort of 493 patients with OPSCC with known p16 tumor status (surrogate of human papillomavirus) and cigarette smoking history (pack-years) randomly assigned to clinical trials using platinum-based chemoradiotherapy (NRG Oncology Radiation Therapy Oncology Group [RTOG] 0129 and 0522). Nomograms were created from Cox models and internally validated by use of bootstrap and cross-validation. Model discrimination was measured by calibration plots and the concordance index. Nomograms were externally validated in a cohort of 153 patients with OPSCC randomly assigned to a third trial, NRG Oncology RTOG 9003. Results Both models included age, Zubrod performance status, pack-years, education, p16 status, and T and N stage; the OS model also included anemia and age × pack-years interaction; and the PFS model also included marital status, weight loss, and p16 × Zubrod interaction. Predictions correlated well with observed 2-year and 5-year outcomes. The uncorrected concordance index was 0.76 (95% CI, 0.72 to 0.80) for OS and 0.70 (95% CI, 0.66 to 0.74) for PFS, and bias-corrected indices were similar. In the validation set, OS and PFS models were well calibrated, and OS and PFS were significantly different across tertiles of nomogram scores (log-rank P = .003;< .001). Conclusion The validated nomograms provided useful prediction of OS and PFS for patients with OPSCC treated with primary radiation-based therapy.
Advanced nodal disease associated with head and neck cancer warrants aggressive, often multi-modality therapy to maximize local-regional control. The expansion of a novel treatment paradigm developed by our institution includes the addition of a single-fraction of high dose spatially-fractionated radiation (GRID) to a conventional course of treatment.Between 1995 and 2002 a series of 27 patients (median age 65) with bulky N2-3 disease were treated. Median nodal tumor size was 7 cm. Two groups of patients were evaluated. Group 1 (N=14) patients received a median neck dose 69 Gy (range 54-79 Gy) plus GRID treatment. Group 2 (N=13) patients received a median neck dose of 59 Gy (range 54-72 Gy) plus GRID treatment followed by planned neck dissection. Patients were evaluated for local-regional control, pathological response, survival, and morbidity.Median time to follow-up for Group 1 was 10 months (range 3-44 months). Neck control was 93%. Disease specific survival was 50%. Morbidity was limited to soft-tissue related damage and was mild. Median time to follow-up for Group 2 was 38 months (range 5-116 months). Pathologic complete response rate was 85%. Overall neck control rate was 92%. Disease specific survival was 85%. Surgical morbidity was limited to three wound healing complications.GRID treatment may be safely added to conventional treatment management of locally advanced neck disease related to cancer with acceptable morbidity. It may improve pathologic complete response rates in those patients who undergo planned neck dissection, possibly leading to improved survival. In patients with inoperable bulky disease, addition of GRID enhances local-regional control.
Summary Prospective analysis was performed of self-reported and biochemically confirmed tobacco use in 50 head and neck cancer patients during treatment. With 93.5% compliance to complete weekly self-report and biochemical confirmatory tests, 29.4% of smokers required biochemical assessment for identification. Accuracy increased by 14.9% with weekly vs. baseline self-reported assessments. Data confirm that head and neck cancer patients misrepresent true tobacco use during treatment.
Tobacco use significantly increases the risk of developing cancer. Moreover, there is growing evidence that tobacco use decreases survival in cancer patients. Nicotine, a systemically available component of tobacco, is associated with tumor promotion and decreased apoptosis in cell culture; however, the role of nicotine on response to radiotherapy (RT) or chemoradiotherapy (CRT) in vivo has not been evaluated. Our study evaluated the effects of nicotine administration on cancer cell survival in cell culture and mouse models. Nicotine increased survival in two cell lines following RT in vitro. Nicotine administration in mice during fractionated RT or CRT increased xenograft regrowth as compared to RT or CRT alone. Nicotine increased hypoxia-inducible factor 1-alpha (HIF-1a) expression in tumor xenografts without altering expression of carbonicanhydrase, a clinical marker of tumor hypoxia. The effects of nicotine on HIF-1a expression were transient, returning to baseline levels within 2-3 days after nicotine removal. Further mechanistic studies indicated that inhibition of phosphoinositide-3-kinase (PI3K) prevented nicotine-mediated increases in HIF-1a expression as well as the prosurvival effects of nicotine on RT. These findings imply that during tobacco use, nicotine may function as a systemic agent through acute and reversible regulation of HIF-1a expression and a decreased therapeutic response.Tobacco use is the most significant preventable risk factor for the development of lung cancer and continued tobacco use during cancer treatment is associated with poor therapeutic outcomes. 1-3 Analysis of the effects of tobacco use in cancer patients demonstrates that smoking decreases survival in both tobacco-related and nontobacco-related cancers. 4 Importantly, the effects of tobacco use appear to be systemic rather than localized and thus supporting the role of a systemically available agent as a mediator of the adverse effects of tobacco.Nicotine is a systemically available agent of tobacco that is currently advocated as a clinical standard of care for smoking cessation. 5 As one of more than 7,000 compounds in tobacco smoke, nicotine has the capacity to penetrate all tissues in the body and bind to a spectrum of nicotinic acetylcholine receptors (nAChR) present on both normal (noncancerous) and cancerous tissue. Nicotinic activation of nAChRs in cancerous tissue leads to broad downstream activation of several tumor promoting proteins including activation of the phosphoinositide kinase-3 (PI3K)-Akt cascade as well as the Ras-Raf-MEK-ERK1/2 cascade, resulting in increased proliferation, angiogenesis, invasion, metastasis and decreased apoptosis. [6][7][8] In parallel, nicotine administration has been shown to decrease the cytotoxic effects of chemotherapy and radiotherapy (RT) in vitro 9-12 ; however, no studies have evaluated the effects of nicotine on therapeutic response in vivo.Separate studies demonstrate that nicotine administration significantly increases hypoxia inducible factor-1 alpha (HIF1a) in vitro. 1...
This study explored using a novel diffuse correlation spectroscopy (DCS) flow-oximeter to noninvasively monitor blood flow and oxygenation changes in head and neck tumors during radiation delivery. A fiber-optic probe connected to the DCS flow-oximeter was placed on the surface of the radiologically/clinically involved cervical lymph node. The DCS flow-oximeter in the treatment room was remotely operated by a computer in the control room. From the early measurements, abnormal signals were observed when the optical device was placed in close proximity to the radiation beams. Through phantom tests, the artifacts were shown to be caused by scattered x rays and consequentially avoided by moving the optical device away from the x-ray beams. Eleven patients with head and neck tumors were continually measured once a week over a treatment period of seven weeks, although there were some missing data due to the patient related events. Large inter-patient variations in tumor hemodynamic responses were observed during radiation delivery. A significant increase in tumor blood flow was observed at the first week of treatment, which may be a physiologic response to hypoxia created by radiation oxygen consumption. Only small and insignificant changes were found in tumor blood oxygenation, suggesting that oxygen utilizations in tumors during the short period of fractional radiation deliveries were either minimal or balanced by other effects such as blood flow regulation. Further investigations in a large patient population are needed to correlate the individual hemodynamic responses with the clinical outcomes for determining the prognostic value of optical measurements.
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