R. Sreeraman

Tobacco Smoking During Radiation Therapy for Head-and-Neck Cancer Is Associated With Unfavorable Outcome

PURPOSE To evaluate the effect of continued cigarette smoking among patients undergoing radiation therapy for head-and-neck cancer by comparing the clinical outcomes among active smokers and quitters. METHODS AND MATERIALS A review of medical records identified 101 patients with newly diagnosed squamous cell carcinoma of the head and neck who continued to smoke during radiation therapy. Each active smoker was matched to a control patient who had quit smoking before initiation of radiation therapy. Matching was based on tobacco history (pack-years), primary site, age, sex, Karnofsky Performance Status, disease stage, radiation dose, chemotherapy use, year of treatment, and whether surgical resection was performed. Outcomes were compared by use of Kaplan-Meier analysis. Normal tissue effects were graded according to the Radiation Therapy Oncology Group/European Organization for the Treatment of Cancer toxicity criteria. RESULTS With a median follow-up of 49 months, active smokers had significantly inferior 5-year overall survival (23% vs. 55%), locoregional control (58% vs. 69%), and disease-free survival (42% vs. 65%) compared with the former smokers who had quit before radiation therapy (p < 0.05 for all). These differences remained statistically significant when patients treated by postoperative or definitive radiation therapy were analyzed separately. The incidence of Grade 3 or greater late complications was also significantly increased among active smokers compared with former smokers (49% vs. 31%, p = 0.01). CONCLUSIONS Tobacco smoking during radiation therapy for head-and-neck cancer is associated with unfavorable outcomes. Further studies analyzing the biologic and molecular reasons underlying these differences are planned.

Initial clinical experience with helical tomotherapy for head and neck cancer

To report a single‐institutional experience with the use of helical tomotherapy (HT)‐based intensity‐modulated radiotherapy (IMRT) for head and neck cancer.

Potential of helical tomotherapy to reduce dose to the ocular structures for patients treated for unresectable sinonasal cancer.

Purpose:To compare intensity-modulated radiotherapy (IMRT) treatment plans generated by segmental multileaf collimator (SMLC) and helical tomotherapy (HT) techniques for patients with unresectable sinonasal cancer. Methods and Materials:SMLC-IMRT and HT-IMRT plans for 5 patients with cancer of the paranasal sinuses and nasal cavity were independently optimized using the Eclipse treatment planning system (Varian Medial Systems, Palo Alto, CA) and Tomotherapy HI-ART treatment planning system (Tomotherapy, Inc, Madison, WI). The goal was to deliver a prescribed dose of 70 Gy to at least 95% of the planning target volume (PTV) encompassing gross tumor over 35 treatments whereas respecting constraints to organs at risk, notably the ocular structures. Results:HT-IMRT reduced the maximum doses to the optic chiasm, as well as to the ipsilateral optic nerve and retina (P < 0.05, for all). Maximum doses to these structures were reduced by 10%, 16%, and 14%, respectively, using HT-IMRT compared with SMLC-IMRT. Additionally, the mean dose to the ipsilateral lacrimal gland was reduced by 32% using HT-IMRT. With respect to conformality, HT-IMRT improved dose homogeneity by decreasing “hot-spots.” The mean percentage of PTV70 receiving greater than 77 Gy (110% of the prescribed dose) was 4.0% for the HT-IMRT plans compared with 17.8% for the SMLC-IMRT plans (P = 0.001). Conclusions:HT-IMRT has the potential to improve dose homogeneity to PTVs whereas reducing dose to the optic structures. Clinical implications are discussed.

Comparison of daily versus nondaily image‐guided radiotherapy protocols for patients treated with intensity‐modulated radiotherapy for head and neck cancer

The purpose of this study was to determine the feasibility of nondaily image‐guided radiotherapy (RT) strategies with intensity‐modulated radiotherapy (IMRT) for head and neck cancer.