(S.S., A.S., A.P., M.B., M.J., J.K. W.)C3H/HeA mice with high incidence of spontaneous breast cancer and Balb1c mice treated with 3,4-benzopyrene (BP) (by painting of the skin resulting in the development of skin cancer) were irradiated with 2,450-MHz microwaves (MW) in an anechoic chamber at 5 or 15 mW/cm2 (2 h daily, 6 sessions per week). C3WHeA mice were irradiated from the 6th week of life, up to the 12th month of life. Balb1c mice treated with BP were irradiated either prior to (over 1 or 3 months) or simultaneously with BP treatment (over 5 months). The appearance of palpable tumors in C,H/HeA mice and of skin cancer in BP-treated Balbic mice was checked every 2 weeks for 12 months. Two additional groups of mice were exposed to chronic stress caused by confinement or to sham-irradiation in an anechoic chamber; these served as controls. Irradiation with M W s at either 5 or 15 mW1cmZ for 3 months resulted in a significant lowering of natural antineoplastic resistance (mean number of lung neoplastic colonies was 2.8 f 1.6 (SD) in controls, 6.1 t 1.8 in mice exposed at 5 mW/cmz and 10.8 2 2.1 in those irradiated at 15 mW1 cm2) and acceleration of development of BP-induced skin cancer (285 days in controls, 230 days for 5 mW/cm* and 160 days for 15 mW/cm2). Microwave-exposed C&I/HeA mice developed breast tumors earlier than controls (322 days in controls, 261 days for 5 mW/cmz and 219 days for 15 mWicm'). A similar acceleration was observed in the development of BP-induced skin cancer in mice exposed simultaneously to BP and MWs (285 days in controls, 220 day for 5 mWicmZ and 121 days for 15 mW1cm'). The acceleration of cancer development in all tested systems and lowering of natural antineoplastic resistance was similar in mice exposed to MW at 5 mW/cm' or to chronic stress caused by confinement but differed significantly from the data obtained on animals exposed at 15 mWicm2, where local thermal effects ("hot" spots) were possible.

PurposeBrachytherapy (BT), due to rapid dose fall off and minor set-up errors, should be superior to external beam radiotherapy (EBRT) for treatment of lesions in difficult locations like nose and earlobe. Evidences in this field are scarce. We describe computed tomography (CT) based surface mould BT for non-melanoma skin cancers (NMSC), and compare its conformity, dose coverage, and tissue sparing ability to EBRT.Material and methodsWe describe procedure of preparation of surface mould applicator and dosimetry parameters of BT plans, which were implemented in 10 individuals with NMSC of nose and earlobe. We evaluated dose coverage by minimal dose to 90% of planning target volume (PTV) (D90), volumes of PTV receiving 90-150% of prescribed dose (PD) (VPTV90-150), conformal index for 90 and 100% of PD (COIN90, COIN100), dose homogeneity index (DHI), dose nonuniformity ratio (DNR), exposure of organs. Prospectively, we created CT-based photons and electrons plans. We compared conformity (COIN90, COIN100), dose coverage of PTV (D90, VPTV90, VPTV100), volumes of body receiving 10-90% of PD (V10-V90) of EBRT and BT plans.ResultsWe obtained mean BT-DHI = 0.76, BT-DNR = 0.23, EBRT-DHI = 1.26. We observed no significant differences in VPTV90 and D90 between BT and EBRT. Mean BT-VPTV100 (89.4%) was higher than EBRT-VPTV100 (71.2%). Both COIN90 (BT-COIN90 = 0.46 vs. EBRT-COIN90 = 0.21) and COIN100 (BT-COIN100 = 0.52 vs. EBRT-COIN100 = 0.26) were superior for BT plans. We observed more exposure of normal tissues for small doses in BT plans (V10, V20), for high doses in EBRT plans (V70, V90).ConclusionsComputed tmography-based surface mould brachytherapy for superficial lesions on irregular surfaces is a highly conformal method with good homogeneity. Brachytherapy is superior to EBRT in those locations in terms of conformity and normal tissue sparing ability in high doses.

Satisfactory local tumor control confirmed the assumption of the study. No residual tumor in the resected specimen (pCR) is the most favorable prognostic factor and determinant of long-term survival. Surgery should not be performed in the patients with persistent N2 disease.

Three experiments were conducted using day-old broiler type chicks to determine the effect of different cereal grains on vitamin D3 utilization and to investigate the effects of rye, corn, wheat and triticale as the cereal grain component of the diets on the development of a rachitic condition in chicks. Rye was submitted to acid treatment and water extraction in an attempt to destroy or isolate the rachitogenic factor. Results showed that with chicks fed a diet containing 200 I.U. of vitamin D3 with corn as the grain, mineralization of their bones was normal. Growth and bone ash were depressed when rye replaced corn in the diet. These effects were partially reversed when either fat or procaine penicillin was added to the diet, and comppletely prevented with a high level of vitamin D3 (2,000 I.U./kg.). In another experiment, triticale depressed bone ash even though it did not affect body growth to the same extent as rye. Our results indicate that the factor responsible for the rachitogenic condition of rye-fed chicks can be removed by water extraction of this grain or partially destroyed by acid autoclaved treatment. A combination of acid autoclaved treatment and penicillin supplementation prevented the depression in bone ash.

Development and growth of skin cancer may be affected by various physical and chemical factors present in human environment. Of these factors electromagnetic radiation of radio- and microwave spectra are among the most common. In the present study Balb/c mice were exposed to chemical carcinogen, 3,4-benzopyrene, painted on the skin every 2nd day for a total of 6 months, and simultaneously irradiated with athermal (5 mW/cm2) or subthermal (15 mW/cm2) doses of 2,450 MHz microwaves. The other group of animals was preirradiated with microwaves at 10 mW/cm2 power level for 1, 2, or 3 months and then treated with benzopyrene, as above. Control mice were exposed for 6 months to benzopyrene, resulting in the development of baso- or spinocellular skin carcinoma within approximately 9 months, and sham-irradiated with microwaves. The growth of the tumour was assessed according to a self-designed 7-range macroscopic scale, supported by microscopical examinations of skin sections. All protocols of microwave irradiations resulted in a significant acceleration of the development of benzopyrene-induced skin cancer and in shortening of life span of the tumour-bearing hosts. This effect seemed to be dose-dependent since subthermal doses (15 mV/cm2) and longer (3 months) expositions to microwaves were more efficient as compared to athermal doses (5 mW/cm2) and shorter preirradiations. In addition, low-level, long-lasting exposure to microwaves led to a marked suppression of delayed hypersensitivity of mice treated with benzopyrene, as assessed by their reactivity to dinitrofluorbenzene (DNFB). It is suggested that the observed co-carcinogenic effect of microwave radiation may, at least in part, result from the inhibitory action of microwaves on cellular immune reactions of exposed animals.