Use of a dosimetry-based RAI protocol for treatment of benign hyperthyroidism optimises response while minimising exposure to ionising radiation.

BACKGROUND: The optimal treatment strategy for radioiodine (RAI) treatment protocols for benign hyperthyroidism remains elusive. Although individualised activities are recommended in European Law, many centres continue to provide fixed activities. Our institution implemented a dosimetry protocol in 2016 following years of fixed dosing which facilitates the calculation of individualised activities based on thyroid volume and radioiodine uptake. METHODS: This was a retrospective study comparing success rates using a dosimetry protocol targeting an absorbed dose of 150 Gy for Graves' disease (GD) and 125 Gy for Toxic Multinodular Goiter (TMNG) with fixed dosing (200MBq for GD and 400MBq for TMNG) among 204 patients with hyperthyroidism. Success was defined as a non-hyperthyroid state at 1 year for both disease states. Results were analysed for disease specific or patient specific modulators of response. RESULTS: This study included 204 patients; 74% (n = 151) received fixed activities and 26% (n = 53) of activities administered were calculated using dosimetry. A dosimetry-based protocol was successful in 80.5% of patients with GD and 100% of patients with TMNG. Differences in success rates and median activity administered between the fixed (204Mbq) and dosimetry (246MBq) cohort were not statistically significant (p = .64) however 44% of patients with GD and 70% of patients with TMNG received lower activities following treatment with dosimetry as opposed to fixed activities. Use of dosimetry resulted in successful treatment and reduced RAI exposure for 36% of patients with GD, 70% of patients with TMNG, and 44% of patients overall. CONCLUSION: This retrospective clinical study demonstrated that treatment with a dosimetry-based protocol for TMNG and GD achieved comparable success rates to fixed protocols while reducing RAI exposure for over a third of patients with GD and most patients with TMNG. This study also highlighted that RAI can successfully treat hyperthyroidism for some patients with activities lower than commonplace in clinical practise. No patient or disease specific modulators of treatment response were established in this study; however, the data supports a future prospective trial which further scrutinises the individual patient factors governing treatment response to RAI.

Atlantic DIP: is weight gain less than that recommended by IOM safe in obese women with gestational diabetes mellitus?

BACKGROUND/OBJECTIVES: The Institute of Medicine (IOM) recommends gestational weight gain (GWG) of 5-9 kg in women with a body mass index (BMI) ≥ 30 kg/m2. Debate continues as to whether GWG less than that recommended is safe in women with gestational diabetes mellitus (GDM). The study objective was to examine maternal and infant outcomes for obese women with GDM who lost weight or gained 0-5 kg during pregnancy. SUBJECTS/METHODS: A 7-year retrospective cohort study of pregnancy outcomes for obese women with GDM recorded in the Atlantic Diabetes in Pregnancy database was conducted. We examined pregnancy outcomes for mothers with GDM and a BMI ≥ 30 who either lost weight or gained 0-5 kg (Group 1, n = 237) and women who gained 5-9 kg (Group 2, n = 77). We further divided groups 1 and 2 into women treated by diet only (GDM-D) (n = 120) and those requiring additional treatment with insulin (GDM-I) (n = 194). RESULTS: GDM-D women in Group 1 were more likely to deliver earlier (38.9 vs 39.8 weeks, p < 0.01), to develop pregnancy induced hypertension (PIH) (15.4% v 0%; p = 0.02) or have a post-partum haemorrhage (PPH) (13.2% vs 0, p = 0.03) compared to women in Group 2. Rates of prematurity were higher in group 1 vs 2 (14.3% vs 0%, p = 0.03). However, further logistic regression analysis adjusted for smoking status, family history of diabetes, ethnicity and age determined no significant difference in maternal or infant outcomes for women in Group 1 compared to those in Group 2. CONCLUSION: In our population, weight gain less than IOM guideline appears safe and is not associated with any further increase in adverse outcomes. However, validation through a prospective study with a larger obese GDM cohort is required before the findings presented here could be recommended for routine clinical use.

Tumour Lysis Syndrome and Partial Remission Occurring After Administration of a Test Dose of Obinutuzumab.

Chronic lymphocytic leukaemia (CLL) is one of the most common haematological malignancies worldwide, with an increasing prevalence in the elderly population. Obinutuzumab is a type II anti-CD20 monoclonal antibody which showed superiority over rituximab in combination chemotherapy with chlorambucil for the treatment of CLL in the CLL11 trial (NCT01010061) and is becoming part of standard first line treatment for CLL in the elderly based on its potent efficacy and benign safety profile. We report the case of a chemotherapy naive patient who develop tumour lysis syndrome despite appropriate prophylaxis, and had partial remission of her disease after receiving only the initial test dose of obinutuzumab. LEARNING POINTS: Chemotherapy-induced tumour lysis syndrome is a serious complication that can occur after even a small dose of chemotherapy.Chronic lymphocytic leukaemia patients with strongly positive CD20 cells can be more sensitive to obinutuzumab chemotherapy.