144

Results: In stage I and II disease the potential 2-ye&r surviv&l is the same

whether radiotherapy has been administered after surgery or not. In stage II squamous

cell ca. the 2 year expected survival was

30% radiation+surgery (if N 2 21.4% and if N -i 26.7%) while with surgery alone 44.4%

(~2 41.6% and N O 1 41.3%). In adenocarci- noma patients operated and then irradia-

ted the 2 year survival was 23.9% (N 2 23.9%, N0_ 1 not assessable) and with sur- gery alone it was 20.2% (if N 2 13.8 per- cent, N_ 1 not assessable).

U- Concluslons

The results show that there is no sig- nificant advantage in the use of adjuvant radiotherapy for squamous cell ca. in stage III patients while it does help in adenocarcinoma at stage III N 2 level.

New Modalities in Radiotherapy of Lung Cancer. Cohen, L. Michael Reese Hospital and Uni- versity of Chicago, Chicago, Illinois 60616, U.S.A.

The feasibility of improved local con- trol of non-small-cell lung cancer (NSCLC) by the use of high linear energy transfer (LET) radiation is explored. From the known radiobiological characteristics of epidermoid and non-epidermoid carcinomas, it is clear that in order to optimize local control of NSCLC without unacceptable side effects, complex physical (dose, time and fractionation) and biological (repair and repopulation ) interactions are involved.

Radiosensitizing drugs and altered fractionation may be helpful in this re- gard. The use of high LET radiations, notably neutrons, greatly simplifies the optimization process and could yield im- proved local control, fewer complications and a wider role for elective chemotherapy.

Of 42 late-stage NSCLC patients treated with neutrons at Fermilab (Chicago) and followed for two or more years, 9 (22%) were locally controlled, 8 (17%) are alive without evident disease and 5 (12%) exhibi- ted significant side effects. Results of other pilot studies and proposed future clinical trials with neutrons and chemo- therapy are discussed.

The Treatment Volume in Radiation Therapy (RT) of Small Cell Lung Cancer (SCLC). M~ntyl~, M., Niiranen, A. Department of Radiotherapy and Oncology and Department of Pulmonary Medicine, University Central Hospital, Helsinki 00290 Finland.

The purpose of this paper is to evaluate the issue of the volume to be irradiated in SCLC: the initial prechemotherapy or the reduced treatment volume following re- sponse to chemotherapy. All patients with

previously untreated SCLC initially recei-

ved 4 cycles of induction chemotherapy (cyclo-

phospham½de 1200 mg/m i.v. d i, vinc~istine 1.3 mg/m 2 i.v.d. 1+8, VP-16 150 mg/m i.v. dl, 200 mg/m p.o. d 3) 3 of which were administe- red before RT and 1 during the 3-week rest in- terval of the split-course regimen consisting of 55 Gy/20F/7 wk to the primary tumor, media- stinum and supraclavicular areas. Maintenance treatment to patients responding (CR,PR) to induction chemotherapy and RT were randomized to one of three arms: maintenance-IFN, mainte- nance chemotherapy or no maintenance treatment at all.

In 28 cases the whole original tumor volume was in the treatment fields and in 24 cases the reduced tumor volume following chemotherapy was included in treatment volume. There was a high proportion of intrathoracic failures outside the field in the group with reduced fields.

Failures Original tumor size Reduced tumor size included tn the included in the trrad.fJelds trrad.f ie lds

no failures 10 1 Iota] (+ distant) S 14 dJ stant only 13 9

The median survival is 12.5 months in the group with original tumor volume in the treat- ment volume (11/28 are living at the mean fol- low-up of 18 months), and 8.5 months in the group with reduced field size (only 1/24 living).

Single Dose Thoracic Irradiation After a Short Intensive Chemotherapy Regimen for the Treat- ment of Small Cell Lung Cancer (SCLC). Stout, R., Thatcher, N. (Manchester Lung Tumour Group) Christie Hospital, Manchester, U.K.

181 patients with SCLC, the majority with "Limited stage", have been treated since 1981 with a 3 month regimen of 3 courses of etopo- side an~ moderate dose cyclophosphamide (1.5- 3.5 ~/m ) followed by methotrexate and irradi- ation of the primary site.

A complete radiological response was achieved in 41% of the patients before radiotherapy was given and this rose to 55% within a month of its completion. There was failure of primary control in 55% of the complete responders who relapsed.

Methotrexate was given 14 days and 24 hours before irradiation to utilise any potential synergism between the drug and x-ray therapy. No increase in early or late radiation morbi- dity was observed but neither was there any evidence of enhanced response.

In our recent study ifosfamide and etoposi- de is given for 6 cycles at 3 weekly intervals. The aim is to increase the number achieving a complete response and reduce the incidence of local and distant relapse.

We have replaced the fractionated course of thoracic irradiation (30 G (3000) in 8 fractions over i0 days using a parallel-opposed pair) with a single exposure of 12.5 G (1250 rad)

145

using a rotation technique. The overall treatment time is still only 4.5 months. The first 25 patients with a maximum follow up of 6 months will be presented, compa- ring the radiotherapy technique, response and morbidity with our previous experience using the fractionated course.

Hypofractionated (0nce-A-Week) Radiation Therapy For Treatment of Advanced Lung Cancer . 1 Poulter_, C., Rubi~ l, P., VanHoutte 2, p.,

Salazar 5, O., Lush-, C. i. University of Rochester, Rochester, New York, U.S.A. 2. Institut Jules Bordet, Bruxelles i000, Belgique. 3. University of Maryland Hospi- tal, Baltimore, Maryland, U.S.A.

Between February 1980 and January 1984, 70 patients with advanced lung cancer were registered to receive 5.00 Gy once weekly to a total dose of 50-60,00 Gy (1826-2050 ret). Seventy-three percent completed treat- ment to at least the 50.00 Gy dose and all cases where therapy was incomplete were attributable to disease symptomatology or progression rather than treatment-related causes. Acute toxicity was, in fact, mini- mal and incidence of late effects such as fibrosis was virtually no different than that found with standard fractionation schedules. Preliminary evaluation of re- sponse yielded a response rate comparable to that achieved with conventional frac- tionation regimens. Final analysis evalua- ting response, disease-free and overall survival rates, acute and late toxicities, with stratification by histologic cell type, is in process.

~ice-A-Week Irradiation for Locally Advan- ced Non-Small Cell Lung Cancer. Alberti, W., Stuschke, M., Niederle, N., Doberauer, C., Scherer, E. West German Tumor Center, Essen. F.R.G.

Radio-oncologic innovations aiming at improvement of the local tumor control include unconventional fractionation sche- mes. Twice-a-week irradiation schedule was investigated at our center in the time period between sep. 81 to mai 84. Thirty eight patients (pts) with inoperable non- small cell lung cancer (limited disease) with a median age of 56 years (range 44 to 76) were irradiated according to the fol- lowing schedule: 2 x 4 Gy per week to a total dose of 52 to 60 Gy. 28 pts (74%) achieved objective tumor response (CR: 5 and PR: 23 pts). Another i0 pts showed stable disease (NC, n=8) or progressive disease (PD, N=2). Fifteen pts are survi- ving. The median observation time of the survivors is 13 months and the median survival for all patients is I0 months. Median survival correlates well with treat- ment response (CR: 15 mo, PR: ii mo, NC +

PD 6 mo). Acute side effects including esopha-

gitis, tracheitis and nausea were common but mild. Late complications such as radiation pneu- monitis or pulmonary fibrosis were clinical insignificant and did not require treatment.

We conclude: i. Hypofractionation schedule leads to high remission rates with tolerable side effects. 2. Therapy failures were mainly encountered when patients developed extensive metastatic disease. Therefore a combined moda- lity approach including radio-/chemotherapy seems to be a suitable therapeutic regimen for such patients.

Interstitial Radiation Therapy - An Extension of Surgery for Lung Carcinoma. Isterabadi, S., Horowitz, B., Kvale, P., Lewis, J. Henry Ford Hospital, Detroit, Michigan.

Over a four year period, 38 patients with pulmonary malignancies underwent 39 radioactive iodine seed implantations (RISI). Irriduim af- terloading catheters were also used in 14% of patients. In 59%, RISI was incidental if re- sectable lesions were found at thoracotomy de- spite negative staging. In 41%, RISI was plan- ned in patients with recurrent neoplasms after chemotherapy or external beam radiation. Pri- mary lung carcinomas (79% of cases) included adeno- 46%, squamous 27%, nonsmall cell undif- ferentiated 17%, and small cell 10%; other chest neoplasms (21%) included metastatic syno- vial cell and osteogenic sarcomas, hemangioperi- cytomas, testicular and thyroid carcinomas, mesothelioma, thymoma, and neuroblastoma. An average of 45 seeds was implanted per patient (range 5-103); the mean irriduim dosage was 2500 RADS (range 1000-4500). There were no hos- pital deaths. Complications included postope- rative bleeding - 1 case, prolonged air leak - i, and fever of unknown origin - 3. The ave- rage tumor diameter of 5.2 cm preoperatively decreased to 3.0 cm at a mean follow-up of 12.0 mo. Progressive disease claimed 26% of this series with a mean time to death of 7.8 mo. 22% of patients with extensive mediastinal or hilar lymph node metastasis survived 18 mo or more while 11% survived 24 mo. or more. Al- though most individuals in this series have not reached end of life, RISI seems to offer a useful surgical approach to patients with unresectable pulmonary malignancies at the time of thoracotomy or limited therapeutic al- ternatives with recurrent carcinoma.

Effect of Treatment Planning With Computed To- mography on Prognosis of Patients With Inope- rable Carcinoma of the Lung. COX, J.D., Derus, S., Gillin, M., Byhardt, R.W., Kline, R.W., Lawlor, P., Reavis, R., Hartz, A. Radiation Oncology Department, Medical College of Wisconsin, Milwaukee, WI.

A retrospective study was undertaken to determine the value of thoracic CT in diagno- sis and treatment planning of patients who received radiation therapy for inoperable or