1100 Radiation Oncology 0 Biology 0 Physics July 1983, Volume 9, Number 7

(that brain irradiation is non-morbid’)-and overlook another impor- tant conceptual advance which has evolved since the initial publications: that of timed restaging including computerized tomography (CT) of the head. With this latter procedure it is probable that brain metastases are detected at an asymptomatic and earlier stage than previously. Therefore, a comparison of quality of life between patients receiving elective versus therapeutic irradiation is not valid by current standards. A more appropriate comparison would include an evaluation of quality of life between elective brain irradiation and those receiving irradiation at time of detection at restaging CT scans (usually asymptomatic). The percentage of patients identified to have brain metastases at a minimally symptomatic or asymptomatic stage should certainly be considerably higher now than in the initial series, which used brain scans upon suspicion of central nervous system involvement. My own conclusion from the article of Rosenman and Choi is not that elective brain irradiation is of value, but that head CT should be a mandatory restaging procedure along with bronchoscopy and others at 6 to I2 months after treatment of small cell carcinoma.

FRANCO M. MUGGIA, M.D. Director Division of Oncology NYU Medical Center 550 First Avenue New York, New York 10016

Ellison, N., Bernath, A., Kane, R., Porter, P.: Disturbing problem of success clinical status of long term survivors of small cell lung cancer. (SCLC) Proc. ASCO 1: 149, 1982. Hansen, H.H.: Should initial treatment of small cell carcinoma include systemic chemotherapy and brain irradiation. Cancer Che- mother. Rep. part 3 4: 239. 1973b. Hansen, H.. Muggia, F.M.: Staging of inoperable patients with bronchogenic carcinoma with special reference to bone marrow examination and peritoneoscopy. Cancer 30: 1395-1401, 1972. Hansen, H.H., Muggia, F.M., Andrews, R., Selawry, S.: Intensive combined chemotherapy and radiotherapy in patients with nonre- sectable bronchogenic carcinoma. Cancer Jo: 3 15-324, 1972.

REBUTTAL

To the Editor: Cure of patients with small-cell carcinoma of the lung by current chemotherapy alone is rather exceptional because of frequent relapses at the primary site, and the brain in addition to the systemic relapse.’ However, a dramatic improvement in the short-term result achieved by the current chemotherapy has been clearly witnessed: a median survival time of patients with the limited stage of the tumor has improved from 5-6 months with radiation therapy alone to l&l4 months with chemotherapy alone or with chemotherapy plus radiation therapy. Patients, who have survived more than the median survival time of l&l4 months, are faced with an increasing risk of recurrence in the brain which can reach as high as 58% at 24 months.’ A comprehensive treatment program aimed at a total cure of patients with small-cell carcinoma of the lung should have a treatment method to prevent a failure in the brain and also along the spinal axis.

We agree with Dr. Muggia that elective cranial irradiation can be potentially morbid. The neurological complications reported by Ellison et 01. are rather unusual and most likely associated with the combination of elective cranial irradiation and neurotoxic chemotherapeutic agents, i.e. methotrexate and vincristine.’ Long-term neurological morbidity has not been a problem when elective cranial irradiation for this tumor has employed a total dose of 2,500 to 3,000 cGy in IO fractions over a period of two weeks.’ Nevertheless, we are sensitive to the issue of neurological morbidity which is a function of radiation dose, and fractionation schedule; the optimum dose which is yet to be determined may be less than 3,000 cGy in IO fractions. The potential gain of elective cranial irradiation also has to be weighed against the expense and inconvenience of this treatment for those who will never develop metastases to the brain.

Alternative methods to prevent recurrence in the brain have to be explored. Therapeutic cranial irradiation for clinically demonstrable metastatic tumor in the brain has been rather ineffective in eliminating the metastatic tumors, although symptomatic relief for a short term of 4-6 months has been excellent.* Dr. Muggia raised an issue of timed re-staging procedure using computed tomography of the brain in place of elective cranial irradiation with an assumption that minimally symptomatic or asymptomatic lesions can be eradicated with a radiation dose which is tolerable by the normal brain tissue. However, asymp- tomatic lesions are not necessarily microscopic and they can be as big as several centimeters in the frontal lobe of the brain. Nonetheless, the issue of timed re-staging procedure using computed tomography of the brain needs to be explored. The experiences that we have learned from the management of patients with acute lymphocytic leukemia have been very useful in the treatment strategies for patients with this tumor.

NOAH C. CHOI, M.D. JULIAN ROSENMAN, M.D. Department of Radiation Therapy Harvard Medical School; Department of Radiation Medicine Massachusetts General Hospital Boston, Mass. 021 I4

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Catane, R., Schwade, J.G., Yarr, I., Lichter, A.S., Tepper, J.E., Dunnick, N.R., Brody, L., Brereton. H.D., Cohen, M., Glatstein, E.: Follow-up neurological evaluation in patients with small-cell lung carcinoma treated with prophylactic cranial irradiation and chemo- therapy. Int. J. Radiat. Oncol. Biol. Phys. 7: 105-109, 1981. Cox, J.D., Komaki. R., Byhardt, R.W., Kun, L.E.: Results of whole-brain irradiation for metastases from small-cell carcinoma of the lung. Cuncer Treat. Rep. 64: 957-96 I, 1980. Ellison, N.. Bernaths, A., Kane, R., Porter, P.: Disturbing problems of success: Clinical status of long-term survivors of small-cell lung cancer. Proc. ASCO 1: 149, 1982. Komaki, R., Cox., J.D., Whitson, W.: Risk of brain metastases from small-cell carcinoma of the lung related to length of survival and prophylactic irradiation. Cancer Treat. Rep. 65: 8 I l-8 14, I98 I. Matthews, M.J., Rozencweig, M., Staquet, M.J., Minna, J.D., Muggia, F.M.: Long-term survivors with small-cell carcinoma of the lung. Eur. J. Cancer 16: 527-531, 1980.