Epidemiological studies have established an association between exposure to radon and carcinoma of the lung. However, based on data for either lung cancer in uranium miners exposed to radon or bronchial epithelial carcinomas in Japanese A-bomb survivors, it has not been possible to assign estimates of risk of lung cancer for the general population exposed to radon in their homes. Based on past success with the excellent quantitative properties of the C3H 10T1/2 in vitro oncogenic transformation assay system, the relative biological effectiveness (RBE) for radiation-induced transformation for charged particles of defined LET has been determined. As the LET of the radiation was increased, the rate of induction of oncogenic transformation increased and the RBEm approached 20. At higher LETs, RBE dropped precipitously. The rapid drop in effectiveness for alpha particles with LETs between 120 and 265 keV/microns implies a lower quality factor than the 20-25 currently considered appropriate when estimating lung cancer mortality.

Dystrophic epidermolysis bullosa (DEB) is a debilitating systemic disease frequently associated with biologically aggressive secondary squamous cell carcinomas arising from affected skin or mucosal surfaces. Treatment of these carcinomas with surgery, chemotherapy, or radiation is complicated by inherently poor wound healing. We report on two DEB patients treated with radiation therapy for locally advanced squamous cell carcinoma, and retrospectively analyze 10 DEB patients treated with radiation, reported in the literature. Of the 11 fully available and described case results from radiation therapy, six (54%) patients demonstrated a partial tumor response. All patients receiving > 4,500 cGy developed moist skin desquamation and delayed skin healing. Radiation therapy may be of benefit in palliating DEB patients who have locally advanced carcinoma, but has been associated with enhanced normal tissue toxicity, suggesting a narrow or absent therapeutic index between irradiated carcinoma and skin.

No abstract

Two children with Wilms' tomor and prior thoracic radiation developed congestive heart failure at cumulative adriamycin doses of 350 mg/m2 and 400 mg/m2. Details of these two cases and a summary of previously reported adriamycin cardiotoxicity in children are presented. Dose recommendations and predictive tests are discussed.Cancer 39:62-65. 1977. DRIAMYCIN IS AN ANTINEOPLASTIC AGENTA with a broad range of clinical activity including many childhood neoplasms. Because it may produce long-term remissions in children with metastatic Wilms' tumor for whom both dactinomycin and vincristine have failed, Adriamycin has been incorporated into the National Wilms' Tumor Study-2. l2 Cardiotoxicity has limited the usefulness of Adriamycin. Numerous reports have detailed the risk factors for cardiotoxicity and discussed predictive tests. Suggested risk factors include: 1 ) pre-existing cardiac or pulmonary diseases; 2) radiation to the heart; 3 ) prior, concurrent, or subsequent therapy with daunorubicin, dactinomycin, mithramycin, cyclophosphamide, or high dose methotrexate. 637311 Tests which have not been proven predictive of cardiotoxicity include cardiac enzymes, electrocardiograms, and chest x-rays. Encouraging results with systolic time intervals and echocardiograms have been reported. 4-13 A recent case report, however, detailed severe Adriamycin cardiotoxicity in spite of normal systolic time intervals during and after a course of Adriamycin.