A Logical levothyroxine dose Individualization: Optimization Approach at discharge from Radioiodine therapy ward and during follow-up in patients of Differentiated Thyroid Carcinoma: Balancing the Risk based strategy and the practical issues and challenge

摘要

In this communication, the authors discuss the issue of individualization of thyrotropin suppressive therapy in differentiated thyroid carcinoma (DTC) patients and share their views with respect to optimizing the dose of levothyroxine (LT) prescription both during discharge from radioiodine therapy ward and during follow-up. The changing management paradigm at our Institute during post-thyroidectomy period and during the preparation for radioiodine scan is also briefly highlighted. Five factors can be identified as important determinants for the dose individualization approach: (1) Persistence or absence of metastatic disease, (2) the risk characteristics of the patient and the tumor (3) patient's clinical profile, symptomatology, and contraindications (4) the feasibility to ensure a proper thyroid stimulating hormone TSH suppression level (depends on patient's socio-economic and educational background, the connectivity with the local physician and his expertise) (5) time period elapsed since initial diagnosis. While discussing each individual case scenario, the authors, based upon their experience in one of the busiest thyroid cancer referral centers in the country, discuss certain unaddressed points in the current guideline recommendations, deviations made and some challenges toward employing them into practice, which could be situation and center specific. In addition to these, the value of clinical examination, patient profile and detailed enquiry about clinical symptomatology by the attending physician in each follow-up visit cannot be overemphasized. According to the authors, this aspect, quite important for dose determination in an individual, is relatively underrepresented in the present guidelines. It would also be worthwhile to follow a conservative approach (till clear data emerges) in patients who have characteristics of “high-risk” disease, but are clinically and biochemically disease free, if no medical contraindications exist and patient tolerates the suppressive therapy well. This would be particularly applicable in the presence of aggressive histopathological variants, where, in the event of recurrence/metastasis, the disease demonstrates adverse prognosis and higher incidence of radioiodine refractoriness. At the end, certain important and noteworthy concepts pertaining to LT prescription that has definitive practical implications for the suppressive therapy in DTC patients are described.Keywords: Differentiated thyroid carcinoma, levothyroxine, thyroid stimulating hormone TSH suppression, thyrotropin-suppressive therapy