Outpatient Radioiodine Therapy for Thyroid Cancer A Safe Nuclear Medicine Procedure

Purposes: To evaluate the dosimetric effect of outpatient radioiodine therapy for thyroid cancer in members of a patient`s family and their living environment, when using iodine-131 doses reaching 7.4 GBq. The following parameters were thus defined: (a) whole-body radiation doses to caregivers, (b) the production of contaminated solid waste, and (c) radiation potential and surface contamination within patients` living quarters. Methods: In total, 100 patients were treated on an outpatient basis, taking into consideration their acceptable living conditions, interests, and willingness to comply with medical and radiation safety guidelines. Both the caregivers and the radiation dose potentiality inside patients` residences were monitored by using thermoluminescent dosimeters. Surface contamination and contaminated solid wastes were identified and measured with a Geiger-Muller detector. Results: A total of 90 monitored individuals received a mean dose of 0.27 (+/- 0.28) mSv, and the maximum dose registered was 1.6 mSv. The mean value for the potential dose within all living quarters was 0.31(+/- 0.34) mSv, and the mean value per monitored surface was 5.58 Bq/cm(2) for all the 1659 points measured. The overall production of contaminated solid wastes was at a low level, being about 3 times less than the exemption level indicated by the International Atomic Energy Agency. Conclusions: This study indicates that the treatment of thyroid cancer by applying radioiodine activities up to 7.4 GBq, on an outpatient basis, is a safe procedure, especially when supervised by qualified professionals. This alternative therapy should be a topic for careful discussion considering the high potential for reducing costs in healthcare and improving patient acceptance.

Clinicopathological evaluation of in vivo epidermal nuclear fluorescence

Nuclear fluorescence in keratinocytes is an occasional phenomenon, often present in autoimmune diseases, especially in connective-tissue disease (CTD); however, its clinical significance remains unclear. To investigate the profile of patients with positive nuclear staining on direct immunofluorescence (DIF) of skin samples. A retrospective analysis of 28 patient records from our immunodermatology laboratory was performed between May 2003 and June 2006. Inclusion criteria were the presence of autoantibodies (IgG, IgA or IgM) or complement (C3) binding keratinocyte nuclei on DIF. The most prevalent diseases related to the nuclear keratinocyte DIF staining were systemic lupus erythematosus (n = 9), mixed CTD (n = 3), overlap syndrome (n = 3), Sjogren`s syndrome (n = 1), and CREST (calcinosis, Raynaud`s phenomenon, oesophageal dysmotility, sclerodactyly and telangiectasia) syndrome (n = 1). Serum antinuclear antibody (ANA) was positive in 20 of 28 patients, with titres varying from 1 : 160 to 1 : 1280. Of the 20 patients with positive anti-nuclear antibodies (ANA), 17 were positive for anti-extractable nuclear antigen antibodies, 12 had anti-SSA/Ro, 11 had anti-SSB/La and 8 had anti-ribonucleoprotein. Eight patients were negative for ANA. Positive predictive value of in vivo ANA for systemic CTDs was 75%. The present data suggest that in vivo ANA evaluation is an additional and feasible auxiliary tool for diagnosing CTDs.