Fine needle aspiration cytology of the papillary thyroid carcinoma with a solid component: A cytological and clinical correlation

Abstract

PTCSC may pre-operatively be identified by detecting its characteristic cytological features in FNA smears, regardless of the proportion of SC within the tumor. Because clinical outcomes of PTCSC remain undetermined, it is imperative to postulate PTCSC as a differential diagnosis, even when classical nuclear features of PTC are present. Diagn. Cytopathol. 2017;45:391-398. © 2017 Wiley Periodicals, Inc.

Cytopathology of Solid Variant of Papillary Thyroid Carcinoma: Differential Diagnoses with other Thyroid Tumors

“…Although we found nuclear elongation in most (89%) of our cases, Baloch et al [24] reported nuclei in SVPTC to be more rounded than oval. INIs were found in 67% of the cases in the current study, not very different from the results reported by Higuchi et al [12] (78%) and Ohashi et al [18] (65%). INIs, as expected, were also seen in most (83%) of cPTCs.…”

“…In the current study, SVPTC constituted 2.8% of the total PTC cases. Conventionally, it has been associated with childhood presentation, prior radiation exposure, and a less favorable prognosis than cPTC [17, 18]. However, a few authors have reported these tumors to have age and prognosis comparable to cPTC and no association with radiation exposure [4, 5, 18].…”

“…There is only 1 other study by Ohashi et al [18] where a comparison of the cytomorphology of SVPTC with cPTC was carried out. They reported both solid nests/syncytial fragments and trabeculae to be significantly more common in SVPTC than in cPTC ( p < 0.001).…”

“…Only 3 studies detailing cytological features of this rare variant have been published [7, 12, 18]; the rest are case reports or lack detailed description [4, 5, 19-22]. We retrospectively evaluated aspiration smears of 9 SVPTC cases we came across over a period of 3 years and compared their various cytomorphological features with those of NIFTP/FVPTC, cPTC, and PDTC.…”

“…While Nikiforov et al [17] used a cutoff of 70% with a solid/trabecular/nested growth pattern in the primary tumor nodule to define SVPTC, a lower value of 50% is being used more commonly and widely [9, 18]. Even the latest (2017) WHO Classification of Tumours of Endocrine Organs does not specify a cutoff and proposes naming a tumor “solid variant” when all or nearly all of the tumor not belonging to any of the other variants has a solid, trabecular, or nested (insular) appearance [1].…”