isotretinoin and Adenoma

Topics: Adenoma; Dermatologic Agents; Facial Dermatoses; Humans; Hyperplasia; Isotretinoin; Male; Middle Aged; Sebaceous Gland Neoplasms; Sebaceous Glands; Treatment Outcome

Retinoic acids (RA) regulate growth and differentiation of normal epithelial tissue. They have been employed in anticancer treatment and showed positive effects in hematopoetic and various epithelial tumors. Experimental data with follicular thyroid tumor cells showed strong evidence of induction of differentiated cell function and antiproliferative effects. Based on these data a consecutive series of 10 patients with advanced thyroid carcinoma were treated with 13-cis-retinoic acid (Roaccutan) 1.5 mg/kg body weight for six weeks. Follow-up demonstrated renewed uptake of radioiodine in 4 of 10 patients allowing performance of further radioiodine therapy. Reduction in tumor size due to antiproliferative effects of RA could not yet be verified.

Topics: Adenoma; Aged; Carcinoma, Papillary; Cell Differentiation; Female; Humans; Iodine Radioisotopes; Isotretinoin; Male; Middle Aged; Thyroid Neoplasms

Aberrant crypts are aggregates of single to multiple colonic crypts evidencing hallmarks of dysplasia and may be the earliest detectable pathological lesions for colon cancer. The aberrant crypt assay has been developed in 2 protocols. In one, putative chemoprevention agents are tested for inhibitory effects when administered concomitantly with a carcinogen. In the other, the objective of this study, aberrant crypts were induced in F344 rats by parenteral injection of the colon carcinogen azoxymethane (AOM) and allowed to develop for 4 weeks, when an average of 90-100 aberrant crypt foci per colon were found in the methylene blue-stained colon. Then, during the second 4 weeks of the experiment, aberrant crypts were allowed to further develop to a frequency of > 150 foci per colon, a time when multi-crypt foci were observed. During this time we tested the inhibitory effects of 4 analgesic drugs and 2 differentiation agents for effects of aberrant crypt growth and development. We found the non-steroidal anti-inflammatory drugs piroxicam, aspirin and ibuprofen, but not acetaminophen, to be effective in suppressing aberrant crypt formation or the progression to foci of multiple aberrant crypts. Treatment with chemosuppressing agents 13-cis-retinoic acid (13-cRA) and 4-hydroxyphenretinamide (4-HPR), known differentiating agents, however, did suppress expansion of aberrant crypt foci, with 13-cRA being the much more potent agent.

Topics: Acetaminophen; Adenoma; Analysis of Variance; Animals; Anti-Inflammatory Agents, Non-Steroidal; Anticarcinogenic Agents; Aspirin; Azoxymethane; Colonic Neoplasms; Drug Screening Assays, Antitumor; Fenretinide; Ibuprofen; Isotretinoin; Male; Piroxicam; Precancerous Conditions; Rats; Rats, Inbred F344

Two female patients with multiple syringomas were treated for 5/6 months with cumulative doses of 9 and 11 g isotretinoin respectively. Clinically, the appearance of the lesions in both patients improved from the third month on. After therapy, the lesions were flattened, softened, and skin coloured. Histologically, a marked reduction of size and numbers of syringomas was observed, and the contents of cystic lesions seemed reduced 6 months after therapy. Ultrastructurally, changes in the cystic and ductal epithelium correspond with the keratin modulating efficacy of the drug, but also point at a drug-induced change in intracellular lipid composition.

Topics: Adenoma; Adult; Female; Humans; Isotretinoin; Microscopy, Electron; Sweat Gland Neoplasms; Tretinoin

Twenty-one patients with severe acne (acne papulopustulosa, acne conglobata, acne cystica), six patients with severe rosacea (rosacea paulopustulosa, rosacea conglobata, rhinophyma), and three patients with tuberous sclerosis were treated with 13-cis-retinoic acid for 6-48 weeks. Most patients had been previously treated with dermabrasion, antibiotics or metronidazole. Dependent on the severeness of the pathological symptoms 13-cis-retinoic acid was administered at a dose of 0.2 to 0.5 mg/kg body weight and was then reduced every 4 weeks. We confirm the sebostatic and antiinflammatory effect of the 13-cis-retinoic acid and long-lasting remissions. Side effects had not been serious.

Topics: Acne Vulgaris; Adenoma; Administration, Oral; Adolescent; Adult; Aged; Female; Humans; Isomerism; Isotretinoin; Male; Middle Aged; Rosacea; Sebaceous Gland Neoplasms; Tretinoin

The inhibitory effect of 13-cis-retinoic acid was tested in conjunction with ethyl carbamate (urethane) induced murine pulmonary adenomas. Continuous feeding of the retinoic acid for 20 weeks did not significantly reduce the number of surface adenomas. No physical evidence of toxicity due to the vitamin A analog was observed in any of the mice. All mice showed a steady weight gain during the 20-week period, and there was no evidence of eye lesions, hemorrhage, bone fractures, fur changes or lethargy.

Topics: Adenoma; Animals; Isotretinoin; Lung Neoplasms; Male; Mice; Mice, Inbred Strains; Neoplasms, Experimental; Tretinoin