226 Abstracts/Lung Cancer 13 (1995) 185-232

Radiotherapy

Increased radioresistance of an in vitro transformed human small cell lung cancer cell line Brodin 0, Arnberg H, Bergh J, Nilsson S. Dept. of Oncology. Akademiska Hospital, Uppsala iJniversi&, Uppsala S-751 85. Lung Cancer (Ireland) 1995; 12: 183-98.

Alter 4-6 months in continuous culture the human small cell lung cancer (SCLC) cell line, U-1906, changed its radiobiological character- istics spontaneonsly. The cell linebecame more radioresistant indicating an increased repair capacity. This change was accompanied by a more adherent growth pattern, a higher clonogeneity, a decrease in the cytokexatin (tissue polypeptide antigen) content and increased ghrcagon and neuron-specific enolase (NSE) production. Other parameters such as the estramustine-binding protein (EMEP) and the proliferation associated antigen Ki-67 were unaltered. This spontaneous transformation in vitro of U-1906 may reflect a clinically important in viva phenomenon of SCLC, which frequently develops resistance both to radio- and chemotherapy.

New therapeutic strategies involving radiation therapy for patients with non-small cell lung cancer Curran WJ Jr. Department of Radiation Oncologv Thomas Jefferson CJniversi@, Philadelphia. PA. Chest 1995;107:6 Suppl:302S-5s.

Recent notable developments have occurred involving radiation therapy (RT) for patients with non-small cell lung cancer (NSCLC). For patients with good performance status with tutresected thoracic tumors, induction cisplatin- based chemotherapy followed by RT has resulted in a significant survival advantage over RT alone in two North American trials. However, the best sequence of administration of these two modalities in NSCLC remains to be determined. For palliation of tumor-related symptoms, efforts under way to improve control of brain metastams include the use of twice-daily cranial RT to a higher total dose, the use of focused radiation boost techniques like stereotactic radiosurgery to small metastatic deposits, and increased use of neurosurgical extirpation. For patients with NSCLC with symptomatic bone metastases, use of wider-field irradiation may benefit selected patients. Memstases to the adrenal gland, liver, and s&cutaneous tissues can be palliated successtitlly by brief coorses of RT. Intrathoracic tumor symptoms are well palliated by brief courses of thoracic RT. As adjuvant therapy following curative surgery, RT reduces the intrathoracic tumor recurrence rate among patients with metastatic tumor foci in hilar or mediastinal lymph nodes.

Thoracic and cranial radiotherapy for limited-stage small cell lung cancer Healey EA, Abner A. 50 Binney St, Boston, MA 02I55. Chest 1995;107:Suppl:249S-254s.

Chemotherapy remains the mainstay of treatment for small cell lung cancer (SCLC). For patients with limited-stage disease, the addition of thoracic radiotherapy confers a moderate improvement in local control and a modest survival benefit, but these improvements come at the cost of increased toxic reactions. The optimal method for integrating chemotherapy and thoracic radiotherapy is unresolved. Concurrent and alternating strategies are appealing because they allow uninterrnpted delivery of chemotherapy, but they have not been proven to be superior to conventional sequential approaches. Based on limited data, delivery of thoracic radiation early in the treatment course may be preferable to delivery later in the conme. There is evidence ofa radiation dose-response

effect for SCLC, and, in standard regimens, thoracic radiation doses in the range of 50 to 60 Gy are recommended. The nse of limited radiation fields (to postchemotherapy tumor volumes) appears reasonable. Results for alternative thoracic radiation fractionation schedules such as accelerated hyperfractionation are promising and worthy of further investigation. The role of prophylactic cranial irradiation (XI) is controversial and should be individualized. It should be considered for the favorabk SU&WqI ofpatients witb hnited-stage discaae who achieve a complete response to chemothetapy and thoracic radiothetapy, Ifgiven, we recommend a total dose of30 to 36 Gy in 2-Gy fraction; PC1 should not be delivered concomitantly with chemotherapy.

Initial report on the effectiveness of high dose rate brachytherapy in the treatment of hemoptysis in lung cancer Sur RK, Mahomed GA, Pacella JA, Levitt VC, Feldman C, Donde B. Department of Radiation OncoIogv Hillbrow Hospital, Private Bag 23140, Joubert Park, Johannesburg 2044. Endocuriether Hyperthermia Gncol 1995;11:101-6.

Fourteen patients with advanced and recurrent lung cancers following a radical course of external beam radiotherapy three to 18 months (mean, ten months) previously were treated with a single fraction of high dose rate intraluminal brachytherapy of 10 Gy for severe uncontrolled hemoptysis. Following treatment, hemoptysis decreased within ten to 24 hours (mean, 15.3 hours) and stopped completely within 72 hours in 13 patients. lkvelve of these 14 patients had no further recurrence of hemoptysis three to nine months following treatment. One patient whose hemoptysis decreased initially died three months later of massive uncontrolled hemoptysis. This hemoptysis was not controlled with a second fraction of 10 Gy. The other patient had recurrent hemoptysis two months after the first brachytherapy treatment. This was treated with a further 10 Gy following which the hemoptysis stopped, and the patient is alive two months after the second treatment. High dose rate intraluminal brachflerapy is effective for the treatment of uncontrolled hemoptysis from recurrent or residual tnmor following a course of radical external beam radiotherapy.

Radiotherapy in non-small cell lung cancer: Optimal doses and schedules Schaake-Koning C. The Netherlands Cancer Institute, Antoni van Leeuwenhoek Huis. Plesmanlaan 121, 1066CX Amsterdam. Lung Cancer (Ireland) 1995;12 Suppl l:S119-23.

The doses and schedules for radiation therapy as applied in Stages IIlB and IIIA non-small cell lung cancer patients show a great variety. Depending on its intent, several purely palliative schemes can be used. When a curative intent scheme is wnsidered, patients can lx treated with a more experimental approach as several options are tested to increase selectively the radiation dose in the tumour areas. If improvements in treatment schemes are proven, new standards can be set.

Radiotherapeutic management of non-small cell lung cancer (NSCLC): An overview based on the clinical trials of the Radiation Therapy Oncology Group (RTOG) Wilson JF, Byhardt RW. Department of Radiation Oncology, Medical College of Ksconsin, 8700 West Wisconsin Avenue, Milwaukee, WI 53226. J Jastro 1995;7: l-10.

Recent clinical trials clarified the role of radiation therapy (RT) in the treatment of non-small cell lung cancer (NSCLC). The evolution of this research is illustrated by a systematic succession of studies conducted