ABSTRACT
During the years 1978-1983, 1100 thyroid biopsies were received in the pathology department of Mosul Medical College. Analysis of these biopsies showed: 79.1% colloid goitre [diffuse and nodular], 9.1% adenoma, 4.3% toxic goitre, 4.3% malignant neoplasm, 2.3% Hashimoto's thyroiditis, 0.5% de Quervain's thyroiditis, 0.3% parasitic infestation, 0.1% Reidle's thyroiditis, 0.1% tuberculosis, 0.1% pyogenic infection. The age and sex distributions were presented and some of the aetiological factors and preventive measures were reviewed
ABSTRACT
The preventive and therapeutic roles of retinoic acid applied as a lotion was evaluated on chemically induced skin tumours by repeated application of 7 - 12 dimethylbenz [a] anthacene [DMBA] on the skin of rats, guinea pigs and mice. Guinea pigs and rats were apparently resistant to DMBA as a skin carcinogen in 50 ug dosage applied repeatedly [2 x/week x 20]. Mice were susceptible to DMBA and skin tumours began to appear after 2 weeks of repeated application of 20 ug of the carcinogen [2 x/wk x 8]. The percentage response of DMBA was 58% with an average of 4.6 tumours/animal. In testing the therapeutic action, the established tumours regressed markedly when painted 3 times a day for one week with 0.05% of retinoic acid. In pre-retinoic treatment, the tumour nodules showed squamous papilloma, keratoacanthoma and acanthosis with hyperkeratosis. But after treatment, there was mild acanthosis with hyperkeratosis yet no actual tumour had remained. The preventive role of retinoic acid was obvious in terms of the number and size of tumours developed after concomitant treatment of the carcinogen and then the retinoic acid [2 x/wk x8] when compared with mice which received the same dosage of the carcinogen alone. The histologic picture of the treated skin of the mice, showed normal dermis with mild chronic inflammatory cells which infiltrated the dermis, but without skin tumours, while others showed thickening of the dermis with hyperkeratosis but no skin tumours