Multifocal Micropapillary Thyroid Cancers: Should We Adopt a More Conservative Approach?

Abstract

Introduction There is a trend toward more conservative management of solitary micropapillary thyroid carcinomas (mPTC). Incidental findings of multifocal mPTC are a regular subject of discussion at multidisciplinary team (MDT) meetings, however, guidance on its management is limited. Methods All patients discussed at the West of Scotland Thyroid Cancer MDT between November 2008 and July 2020 with multifocal mPTC (10mm or less) on the first surgical pathology specimen were included. Cases with solitary mPTC on the first surgical pathology specimen were excluded, as were any cases with pathology that would alter prognosis e.g. papillary carcinoma >10mm. Results 52 patients were included in the final analysis, representing 6% of the total cases discussed at the Thyroid cancer MDT. The incidence has increased over time. 76.9% (40) of cases were female with a mean age of 48.6. Median follow up was 23.5 months (Range 1–119). 15.4% (8) of cases had pathological lymphadenopathy on pre-operative imaging. Capsular or vascular invasion and extrathyroid extension were common (26.9%, 9.6% and 32.7% of cases respectively). 55.8% (29) of cases underwent additional treatment after the finding of multifocal mPTC. Overall, 1 (1.9%) patient developed recurrence and is still alive at 75 months follow up after salvage treatment. 1 (1.9%) patient died during follow up, not felt to be related to their thyroid disease. Conclusion Multifocal mPTC is an increasingly common MDT discussion. Recurrence rates are low and may respond well to salvage therapy. A more conservative approach may be an appropriate management strategy for this patient cohort.