Ethnic differences in patients undergoing thyroidectomy for non-toxic multinodular goitre.

BACKGROUND: Maori have an increased incidence of thyrotoxicosis when compvared to non-Maori, however there are limited data on benign non-toxic nodular thyroid disease. AIMS: The aims of this study were to determine the rates of non-toxic multinodular goitre (NTMNG) surgery for Maori and non-Maori and to determine if there were differences in thyroid size between Maori and non-Maori undergoing total thyroidectomy for NTMNG. METHODS: Single centre study of patients undergoing thyroidectomy for NTMNG from 1 December 2006 to 30 November 2016. RESULTS: Maori were overrepresented amongst the 427 patients who underwent surgery for NTMNG at 34% compared to the expected ~17% of the background Maori adult population in the region. At the time of surgery, Maori were younger (P = 0.004) and had a larger thyroid gland (P < 0.001) when compared to non-Maori also undergoing total/near total thyroidectomy. Complication rates were low across all ethnic groups. CONCLUSION: Maori have increased rates of surgery for NTMNG compared to non-Maori and thyroid size is larger at the time of surgery. The reasons for this are currently unknown and more research is required.

The cost of investigating weight-related comorbidities in children and adolescents in Aotearoa/New Zealand.

AIM: Expert recommendations for child/adolescent obesity include extensive investigation for weight-related comorbidities, based on body mass index (BMI) percentile cut-offs. This study aimed to estimate the cost of initial investigations for weight-related comorbidities in children/adolescents with obesity, according to international expert guidelines. METHODS: The annual mean cost of investigations for weight-related comorbidities in children/adolescents was calculated from a health-funder perspective using 2019 cost data obtained from three New Zealand District Health Boards. Prevalence data for child/adolescent obesity (aged 2-14 years) were obtained from the New Zealand Health Survey (2017/2018), and prevalence of weight-related comorbidities requiring further investigation were obtained from a previous New Zealand study of a cohort of children with obesity. RESULTS: The cost of initial laboratory screening for weight-related comorbidities per child was NZD 28.36. Based on national prevalence data from 2018/2019 for children with BMI greater than the 98th percentile (obesity cut-off), the total annual cost for initial laboratory screening for weight-related comorbidities in children/adolescents aged 2-14 years with obesity was estimated at NZD 2,665,840. The cost of further investigation in the presence of risk factors was estimated at NZD 2,972,934. CONCLUSIONS: Investigating weight-related comorbidities in New Zealand according to international expert guidelines is resource-intensive. Ways to further determine who warrants investigation with an individualised approach are required.

Rates of unsuspected thyroid cancer in multinodular thyroid disease.

BACKGROUND: Previously the risk of concomitant thyroid cancer in multinodular goitre (MNG) has been reported as approximately 4%. Cancer risk in toxic MNG was often considered lower than for non-toxic MNG, due to a possible protective effect of TSH suppression. However, recent American data suggest an approximately 18% risk of occult malignancy in both toxic and non-toxic MNG. AIMS: To assess malignancy risk in a New Zealand population undergoing thyroidectomy for MNG. METHODS: Single-centre study of patients undergoing thyroidectomy for MNG from 1 December 2006 to 30 November 2016. RESULTS: Six hundred and two patients underwent surgery for MNG (448 non-toxic and 154 toxic). Of these, 95/602 (16%) had thyroid cancer. After excluding patients operated for preoperative suspicion for cancer, 30/401 (8%) patients with non-toxic MNG and 15/151 (10%) with toxic MNG had unsuspected or occult thyroid cancer (p=0.358). Patients with toxic MNG were less likely to undergo preoperative fine needle aspiration than those with non-toxic MNG (34% vs 52%, respectively p=0.0001). Two-thirds of unsuspected thyroid cancers were incidental micropapillary carcinomas and unlikely to alter survival irrespective of therapy. CONCLUSION: Malignancy rates in MNG are higher than historically reported, although most unsuspected cancers are unlikely to alter mortality even if diagnosis is delayed.