M. Katin

Radiation therapy in the management of medically inoperable carcinoma of the lungs: Results and implications for future treatment strategies

Surgery is the treatment of choice for resectable non-small cell lung carcinoma. For patients who are medically unable to tolerate a surgical resection or who refuse surgery, radiation therapy is an acceptable alternative. We reviewed the records of 152 patients with medically inoperable non-small cell lung carcinoma treated at our institution between 1982 and 1990. Patients with metastatic disease, mediastinal lymph node involvement or unresectable tumors were excluded. The actuarial overall survival at 2 and 5 years was 40% and 10%, respectively. The disease-free survival at 2 and 5 years was 31% and 15%. The disease-free survival for patients with T1 tumors was 55% at 2 years, versus 20 and 25% for T2 and T3 lesions, respectively (p = .0006). Increasing tumor dose was also associated with increasing disease-free survival (p = .0143). Overall, 66% percent of the patients were considered to have failed. Of these, 70% showed a component of local failure and 45% failed distantly. Patients with T1 tumors experienced a lower probability of failing locally or distantly than did patients with T2 or T3 tumors. A reduced risk of local and distant failure was seen for patients treated to doses of greater than 65 Gray, especially for T1 tumors. We conclude that radical radiation therapy is an effective treatment for small tumors when treated to doses of 65 Gray or more. Since local failure is the prominent pattern of relapse in patients with large tumors, new therapeutic strategies should be considered for this patient group.

Local control in medically inoperable lung cancer: An analysis of its importance in outcome and factors determining the probability of tumor eradication

PURPOSEnFor patients who are medically unable to tolerate a surgical resection for technically resectable non-small-cell lung carcinoma, radiation therapy is an acceptable alternative. We report on the effect of achieving local control of the primary tumor on survival end-points, and analyze factors that may influence local control.nnnMETHODS AND MATERIALSnWe reviewed the records of 152 patients with medically inoperable non-small-cell lung carcinoma treated at our institutions. All patients had technically resectable lesions and no evidence of metastatic disease. Treatment was delivered using megavoltage irradiation to doses ranging from 45 to 75 Gy.nnnRESULTSnFor patients with tumors 3 cm or less, locally controlling the tumor significantly improved survival (p = .0371). Patients with T1 tumors had a higher probability of survival and disease-free-survival than patients with larger tumors if the primary tumor was locally controlled, but this survival advantage disappeared if the tumor was not controlled. Overall, patients with smaller tumors had a lower incidence of distant spread, but this association was maintained only when the primary tumor was controlled (36 month risk of 10%, 23%, and 57% for tumors < 3 cm, 3-4.9 cm, 5 cm or greater, respectively, p = .0027). For patients whose tumors were not controlled, there was no significant difference in the risk of distant dissemination by tumor size. Higher radiation doses influenced local control and metastatic spread. We observed no influence of the initial field size in the risk of local control and in the probability of survival.nnnCONCLUSIONnRadical radiation therapy is an effective treatment for small (T1 or < 3 cm) tumors when treated to doses of 65 Gy or more, and should be offered as an alternative to surgery in elderly or infirm patients. New therapeutic strategies to improve the local control rate should be considered for larger tumors, through the use of hyperfractionated treatment, endobronchial boost irradiation, and sensitizing chemotherapy agents.

Medically inoperable lung carcinoma: The role of radiation therapy

Although surgery has traditionally been the treatment of choice for patients with resectable non-small cell lung cancer, for those with significant medical problems where surgery is contraindicated, radiation therapy (RT) is a reasonable treatment modality. In contrast to the widely held belief that RT confers little benefit to these patients, a review of the literature and our own series of 245 patients shows that RT can provide significant tumor shrinkage, improved symptoms, and in a small but not negligible number of patients, cure. Several prognostic factors have emerged, including patient performance status, prior weight loss, tumor size, and radiation dose. Patients with a good performance status and a small tumor treated to a dose of 65 Gy or more have a real possibility of long-term survival and cure. Larger tumors demand strategies to improve the therapeutic ratio, such as hyperfractionation, conformal RT, brachytherapy boosts, or chemotherapy. Patients with medically inoperable lung cancer should be offered RT with curative intent, rather than the option of no treatment.

Low doses of prophylactic cranial irradiation effective in limited stage small cell carcinoma of the lung.

PURPOSEnProphylactic cranial irradiation (PCI) for the prevention of brain metastasis in small cell lung cancer remains controversial, both in terms of efficacy and the optimal dose-fractionation scheme. We performed this study to evaluate the efficacy of PCI at low doses.nnnMETHODS AND MATERIALSnOne hundred and ninety-seven patients were referred to our institution for treatment of limited stage small cell carcinoma of the lung between June 1986 and December 1992. Follow-up ranged from 1.1 to 89.8 months, with a mean of 19 months. Eighty-five patients received PCI.nnnRESULTSnPatients receiving PCI exhibited brain failure in 15%, while 38% of untreated patients developed metastases. This degree of prophylaxis was achieved with a median total dose of 25.20 Gy and a median fraction size of 1.80 Gy. At these doses, acute and late complications were minimal. Patients receiving PCI had significantly better 1-year and 2-year overall survivals (68% and 46% vs. 33% and 13%). However, patients with a complete response (CR) to chemotherapy and better Karnofsky performance status (KPS) were overrepresented in the PCI group. In an attempt to compare similar patients in both groups (PCI vs. no PCI), only patients with KPS > or = 80, CR or near-CR to chemotherapy, and treatment with attempt to cure, were compared. In this good prognostic group, survival was still better in the PCI group (p = 0.0018).nnnCONCLUSIONnIn this patient population, relatively low doses of PCI have accomplished a significant reduction in the incidence of brain metastasis with little toxicity. Whether such treatment truly improves survival awaits the results of additional prospective randomized trials.