King Abdulaziz Medical CIty, Kingdom of Saudi Arabia
Title: A Recent Paradigm Shift in a Common Thyroid Neoplasm Diagnosis and Management: A single institutional experience
Biography: Hatim Q Al-Maghraby
Background: Encapsulated Follicular Variant of Papillary Thyroid Carcinoma (EFV-PTC) is a common subtype of Papillary Thyroid Carcinoma (PTC) with low malignant potential. Based on capsular and vascular invasion they are divided into Non-Invasive and Invasive subtypes (NIEFV-PTC and IEVV-PTC, respectively). Recently a proposal by international groups of thyroid disease experts has been made to re-classify non-invasive encapsulated follicular variant of papillary thyroid carcinoma as a non-malignant thyroid neoplasm and to use the term: “Noninvasive Follicular Thyroid Neoplasm with Papillary-Like Nuclear Features (NIFTP)”. In this study, we identified the clinic-pathological characteristics and management of NIEFV-PTC at King Abdul-Aziz Medical City, Jeddah during 2011-2015.
Methods: A retrospective review of all pathological reports of thyroidectomy specimen with a malignant diagnosis. All cases of EFV-PTC were included as well as other common variants of PTC for comparison. All pathological diagnoses were reviewed by a board-certified pathologist. Additional needed data were obtained by reviewing patient’s charts.
Results: A total of 69 EFV-PTCs (44 non-invasive, 25 invasive) accounting for 28% of all PTC. EFV-PTC had significantly larger tumor size than PTC (P<0.001). NIEFV-PTC tend to be uni-focal compared to invasive EFV-PTC (p=0.006). None of the NIEFV-PTCs showed peri-neural invasion/extra-thyroidal extension/lympho-vascular invasion/lymph node metastasis. 56.8% (n=25) of NIEFV-PTC were managed by surgery and radioactive iodine ablation with a mean dose of 92.82 MCI.
Conclusion: Our local institutional experience indicates that NIEFV-PTC tumors were over staged and treated as conventional thyroid cancer despite an indolent behavior. Adopting the NIFTP terminology in accordance with the recent recommendations might significantly reduce the over-treatment and its associated complications. Where are the conventional PTC cases?? NIEFV-PTC is an indolent thyroid tumor with very low-likelihood of metastases. To avid over-treatment, we recommend the incorporation of the recently coined term (NIFTP) into the diagnosis and management algorithms for patients with thyroid tumors.