Over the past two decades, studies of the Southwest Oncology Group have consistently reported stable esophagitis rates despite changing scales with concurrent chest radiotherapy and ...cisplatin/etoposide regimens. Patient selection has perhaps contributed to increased survival over this period. The Southwest Oncology Group has incorporated surgical questions and advanced the field with a steady use of consistent therapies (ie, cisplatin/etoposide plus radiotherapy of 45 Gy induction therapy and cisplatin/etoposide plus at least 61 Gy) in potentially operable or unresectable disease. Further studies examining the addition of either docetaxel or novel agents to such regimens are underway.
To review the University of Michigan clinical experience in nonsmall cell lung cancer using high-dose thoracic irradiation (> or = 60 Gy) so that a starting dose for our prospective dose-escalation ...study could be determined.
Eighty-eight consecutive patients diagnosed with medically inoperable or locally advanced, unresectable nonsmall cell lung cancer were identified who were treated with thoracic irradiation alone to a minimum total dose of 60 Gy (uncorrected for lung density). All patients except four (95%) underwent computed tomography scanning for treatment planning that included beam's eye view display for tumor and critical structure localization. All patients were treated with standard fractionation in a continuous course to uncorrected total doses ranging from 60 to 74 Gy (median, 67.6 Gy).
The median follow-up exceeds 24 months for all surviving patients (range, 12 to 78 months). The median survival time was 15 months, and the 2- and 3-year overall actuarial survival rates were 37% and 15%, respectively. Survival was significantly different between stage of disease (p = .004) and N-stage (p = .002) by univariate analysis. In a multivariate analysis, stage becomes the only characteristic significantly associated with outcome. The median time to local progression for 86 evaluable patients was 29 months. Stage (p = .0003), T-stage (p = .0095) and N-stage (p = .027) were significantly different with respect to local progression-free survival by univariate analysis. However, only stage was prognostic for local progression-free survival by multivariate analysis. There was no difference between large volume treatment (inclusion of the contralateral hilar and supraclavicular lymph nodes) and small volume treatment (exclusion of these elective nodal sites) with respect to local progression-free survival (p = .507) or survival (p = .520). With regard to dose, there was no significant difference between patients who received > 67.6 Gy and patients who received < or = 67.6 Gy with respect to local progression-free survival (p = .094) or survival (p = .142). Within the Stage III subgroup, local progression-free survival (p = .018) and survival (p = .061) were longer favoring the high-dose group of patients. Despite these doses, disease progression within the irradiated field was the predominant first site of treatment failure.
This retrospective study has shown that it is feasible to deliver uncorrected tumor doses as high as 70 Gy using standard fractionation in NSCLC with acceptable morbidity. Local control remains a significant problem. These data indicate justification for a starting dose in a prospective radiation dose-escalation study.
This study reports our clinical experience supporting the normal tissue-sparing capability of 3-dimensional (3-D) treatment planning when applied to advanced neoplasms of the paranasal sinuses.
...Between 1986 and 1992, computed tomography (CT)-based 3-D radiotherapy was used to treat 39 patients with advanced stage malignant tumors of the paranasal sinuses as all or part of initial treatment. Fifteen unresectable patients were treated with primary radiotherapy to a median prescribed total dose of 68.4 Gy. Twenty-four patients were treated with postoperative adjuvant radiotherapy for close margins (< 5 mm), microscopic or gross residual disease. The median prescribed total doses were 55.8 Gy, 59.4 Gy and 67.8 Gy, respectively. Globe-sparing fields were used in the primary treatment plans of 37 patients (95%). The median follow-up is 4.5 years (range, 19-86 months).
For the unresectable patients who were treated with radiotherapy alone, the local control rate at 3 years is 32%. The actuarial overall survivals at 3 and 4 years are 32%. For the patients who received postoperative adjuvant radiotherapy, none of the five patients irradiated for close surgical margins recurred locally. Three of the 14 with microscopic residual (21%) recurred locally at 26, 63, and 74 months from the start of irradiation. Four of the five with gross residual (80%) recurred locally with a median time to recurrence of 2 years. The local control rates at 3 and 5 years for the adjuvant group are 75% and 65%, respectively. The actuarial overall survival at 3 and 5 years are 65% and 60%, respectively. None of the first sites of local disease progression were judged to have occurred outside the high-dose region. There was one case of mild osteoradionecrosis successfully treated with conservative treatment, one case of limited optic neuropathy and one case of possible radiation-induced cataract. There was no blindness related to irradiation.
This study indicates that computed tomography-based 3-D radiotherapy can preserve critical structures unaffected by tumor invasion and achieve the generally expected local control rates when it is used as all or part of initial treatment for extensive malignant tumors of the paranasal sinus. The presence of gross disease was a major adverse prognostic factor in this study. Additional therapeutic maneuvers are essential to improve the local control and survival rate in patients with advanced paranasal sinus carcinomas.
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