BACKGROUND: It is unclear whether differentiated thyroid cancer (DTC) patients classified as intermediate risk based on the presence of microscopic extrathyroidal extension (ETE) should be treated with low or high doses of radioiodine (RAI) after surgery. We evaluated success rates and long-term clinical outcomes of patients with DTC of small tumor size, microscopic ETE, and no cervical lymph node (LN) metastasis treated either with a low (1.1 GBq) or high RAI dose (5.5 GBq). METHODS: This is a retrospective analysis of a historical cohort from 2000 to 2010 in a tertiary referral hospital. A total of 176 patients with small (≤2 cm) DTC, microscopic ETE, and no cervical LN metastasis were included. Ninety-six patients were treated with 1.1 GBq (LO group) and 80 patients with 5.5 GBq (HI group). Successful RAI therapy was defined as (i) negative stimulated thyroglobulin (Tg) in the absence of Tg antibodies, and (ii) absence of remnant thyroid tissue and of abnormal cervical LNs on ultrasonography. Clinical recurrence was defined as the reappearance of disease after ablation, which was confirmed by cytologically or pathologically proven malignant tissue or of distant metastatic lesions. RESULTS: There was no significant difference in the rate of successful RAI therapy between the LO and HI groups (p=0.75). In a subgroup analysis based on tumor size, success rates were not different between the LO group (34/35, 97%) and the HI group (50/56, 89%) in patients with a tumor size of 1-2 cm (p=0.24). In patients with smaller tumor size (≤1 cm), there was no significant difference in success rates between the LO (59/61, 97%) and HI groups (22/24, 92%; p=0.30). No patient had clinical recurrences in either group during the median 7.2 years of follow-up. CONCLUSIONS: Low-dose RAI therapy is sufficient to treat DTC patients classified as intermediate risk just by the presence of microscopic ETE.
BACKGROUND: It is unclear whether differentiated thyroid cancer (DTC) patients classified as intermediate risk based on the presence of microscopic extrathyroidal extension (ETE) should be treated with low or high doses of radioiodine (RAI) after surgery. We evaluated success rates and long-term clinical outcomes of patients with DTC of small tumor size, microscopic ETE, and no cervical lymph node (LN) metastasis treated either with a low (1.1 GBq) or high RAI dose (5.5 GBq). METHODS: This is a retrospective analysis of a historical cohort from 2000 to 2010 in a tertiary referral hospital. A total of 176 patients with small (≤2 cm) DTC, microscopic ETE, and no cervical LN metastasis were included. Ninety-six patients were treated with 1.1 GBq (LO group) and 80 patients with 5.5 GBq (HI group). Successful RAI therapy was defined as (i) negative stimulated thyroglobulin (Tg) in the absence of Tg antibodies, and (ii) absence of remnant thyroid tissue and of abnormal cervical LNs on ultrasonography. Clinical recurrence was defined as the reappearance of disease after ablation, which was confirmed by cytologically or pathologically proven malignant tissue or of distant metastatic lesions. RESULTS: There was no significant difference in the rate of successful RAI therapy between the LO and HI groups (p=0.75). In a subgroup analysis based on tumor size, success rates were not different between the LO group (34/35, 97%) and the HI group (50/56, 89%) in patients with a tumor size of 1-2 cm (p=0.24). In patients with smaller tumor size (≤1 cm), there was no significant difference in success rates between the LO (59/61, 97%) and HI groups (22/24, 92%; p=0.30). No patient had clinical recurrences in either group during the median 7.2 years of follow-up. CONCLUSIONS: Low-dose RAI therapy is sufficient to treat DTCpatients classified as intermediate risk just by the presence of microscopic ETE.
Authors: C Nascimento; I Borget; A Al Ghuzlan; D Deandreis; L Chami; J P Travagli; D Hartl; J Lumbroso; C Chougnet; L Lacroix; E Baudin; M Schlumberger; S Leboulleux Journal: Endocr Relat Cancer Date: 2011-03-03 Impact factor: 5.678
Authors: David S Cooper; Gerard M Doherty; Bryan R Haugen; Bryan R Hauger; Richard T Kloos; Stephanie L Lee; Susan J Mandel; Ernest L Mazzaferri; Bryan McIver; Furio Pacini; Martin Schlumberger; Steven I Sherman; David L Steward; R Michael Tuttle Journal: Thyroid Date: 2009-11 Impact factor: 6.568
Authors: Bryan R Haugen; Erik K Alexander; Keith C Bible; Gerard M Doherty; Susan J Mandel; Yuri E Nikiforov; Furio Pacini; Gregory W Randolph; Anna M Sawka; Martin Schlumberger; Kathryn G Schuff; Steven I Sherman; Julie Ann Sosa; David L Steward; R Michael Tuttle; Leonard Wartofsky Journal: Thyroid Date: 2016-01 Impact factor: 6.568
Authors: Ayanthi Wijewardene; Matti Gild; Carolina Nylén; Geoffrey Schembri; Paul Roach; Jeremy Hoang; Ahmad Aniss; Anthony Glover; Mark Sywak; Stan Sidhu; Diana Learoyd; Bruce Robinson; Lyndal Tacon; Roderick Clifton-Bligh Journal: Eur Thyroid J Date: 2021-05-25
Authors: Nicholas S Andresen; John M Buatti; Hamed H Tewfik; Nitin A Pagedar; Carryn M Anderson; John M Watkins Journal: Eur Thyroid J Date: 2017-03-23
Authors: Norra Kwong; Ellen Marqusee; Michael S Gordon; P Reed Larsen; Jeffrey R Garber; Matthew I Kim; Erik K Alexander Journal: Endocr Connect Date: 2014-10-14 Impact factor: 3.335