phosphorus-radioisotopes and Adenoma

The induction of DNA adducts and adenomas in the lungs of strain A/J mice has been investigated following the single i.p. administration of each of the following polycyclic aromatic hydrocarbons (PAH): pyrene, dibenz[a,h]anthracene, benzo[a]pyrene, benzo[b]fluoranthene, 5-methylchrysene, and cyclopenta[c,d]pyrene. DNA adducts were measured by 32P-postlabeling at times between 1 and 21 days following injection, while adenomas were counted at 240 days after treatment. Pyrene did not induce either DNA adducts or lung adenomas at any of the doses examined. Each of the remaining PAH induced both adenomas and DNA adducts in a dose-dependent manner, with dibenz[a,h]anthracene > 5-methylchrysene > cyclopenta[c,d]pyrene > benzo[a]pyrene > benzo[b]fluoranthene. DNA adducts reached maximal levels between 3 and 9 days after injection, followed by a gradual decrease. The time-integrated DNA adduct level (TIDAL) was calculated by numerically integrating the areas under the adduct persistence curves extrapolated to 240 days for each PAH at each dose level. This value represents the effective total molecular dose of PAH that was delivered to the lung DNA over the entire course of tumorigenesis. A strong correlation of lung adenoma induction with the TIDAL values was observed for each PAH. The slopes of the tumors versus TIDAL value relationships were essentially identical for 5-methylchrysene, cyclopenta[cd]pyrene, benzo[a]pyrene, and benzo[b]fluoranthene. The slope of this relationship for dibenz[a,h]anthracene was markedly greater. The essentially identical induction of adenomas as a function of TIDAL values for these PAH suggests that the formation and persistence of DNA adducts determines their carcinogenic potency.

Topics: Adenoma; Animals; Caprylates; DNA Adducts; Injections, Intraperitoneal; Lung; Lung Neoplasms; Male; Mice; Mice, Inbred A; Phosphorus Radioisotopes; Polycyclic Compounds; Time Factors; Triglycerides

DNA from human brain tumor samples was analysed by the 32P-postlabeling technique for the presence of aromatic DNA adducts. Thirteen out of 16 samples showed low levels of adducts at 0.14-3.53 adducts per 10(9) nucleotides. Inter-individual variations in the patterns of these aromatic adducts were observed. On the other hand, none of 5 brain samples from epilepsy patients revealed any evidence of such adducts. The data demonstrated the presence of low level, large molecule aromatic DNA adducts in malignant brain tissues and these adducts may either result from environmental exposure to an undetermined genotoxic agent or from the aging process.

Topics: Adenoma; Adult; Aged; Brain Chemistry; Brain Neoplasms; Carcinogens; Carcinoma, Squamous Cell; Chromatography, Thin Layer; Cytochrome P-450 Enzyme System; DNA Damage; DNA, Neoplasm; Epilepsy; Female; Glioma; Humans; Male; Meningioma; Middle Aged; Neurilemmoma; Phosphorus Radioisotopes; Pituitary Neoplasms; Polycyclic Compounds

The authors report on 40 brain tumor patients treated with CT-guided stereotactic injection of 198Au and 32P. Among the 40 cases were astrocytoma in 23 cases, craniopharyngioma in 9, meningioma in 4, pituitary adenoma in 2, and pinealoma and metastatic carcinoma each in 1 case. The tumors were all located in deep or important areas of the brain which were difficult to deal with by conventional operation. 62 injections of colloidal isotopes were performed, and all were successful. No major adverse effects or complications occurred on follow-up of 6-12 months, 28 patients were improved in their clinical symptoms, and CT scanning showed that the tumor sizes were diminished. The effective rate is 70%.

Topics: Adenoma; Adult; Astrocytoma; Brain Neoplasms; Craniopharyngioma; Female; Gold Radioisotopes; Humans; Male; Meningeal Neoplasms; Meningioma; Phosphorus Radioisotopes; Pinealoma; Pituitary Neoplasms; Radiosurgery; Stereotaxic Techniques; Tomography, X-Ray Computed

Topics: Adenoma; Humans; Hyperparathyroidism; Neoplasm Recurrence, Local; Parathyroid Hormone; Parathyroid Neoplasms; Phosphorus Radioisotopes; Radionuclide Imaging; Semiconductors

The 32P uptake test used in the differential diagnosis of 912 cases yielded an accuracy rate of 94.82% for intraocular lesions behind the equator, and 85.15% for lesions of the anterior uvea. The highest error rate occurred in patients with suspected tumors of the iris and ciliary body. It seems advisable to take a 40% difference on the uptake as the limit between a positive or negative test result.

Topics: Adenoma; Choroid Neoplasms; Ciliary Body; Diagnosis, Differential; Eye Neoplasms; False Negative Reactions; False Positive Reactions; Humans; Iris Diseases; Melanoma; Phosphorus Radioisotopes; Retinal Hemorrhage; Sarcoma, Kaposi; Uveal Neoplasms

A benign adenoma of the pigment epithelium of the ciliary body in a 27-year-old woman simulated a malignant melanoma clinically and resulted in enucleation. The correct diagnosis was not made clinically despite the use of A- and B- scan ultrasonography and the radioactive phosphorus (32P) uptake test, procedures which are usually reliable in differentiating between melanoma and pseudomelanoma. We emphasize the shortcomings of these ancillary tests in differentiating pigment epithelial tumors from malignant melanoma.

Topics: Adenoma; Adult; Ciliary Body; Diagnosis, Differential; Diagnostic Errors; Eye Neoplasms; Female; Humans; Melanoma; Ophthalmoscopy; Phosphorus Radioisotopes; Pigment Epithelium of Eye; Ultrasonography; Vision Disorders; Visual Acuity