Perineural Invasion in Papillary Thyroid Cancer: A Rare Indicator of Aggressive Disease.

TitlePerineural Invasion in Papillary Thyroid Cancer: A Rare Indicator of Aggressive Disease.
Publication TypeJournal Article
Year of Publication2023
AuthorsLimberg J, Lee-Saxton YJ, Egan CE, AlAnazi AA, Easthausen I, Stefanova D, Stamatiou A, Beninato T, Zarnegar R, Scognamiglio T, Fahey TJ, Finnerty BM
JournalAnn Surg Oncol
Date Published2023 Jun
KeywordsCarcinoma, Papillary, Humans, Neoplasm Recurrence, Local, Prognosis, Retrospective Studies, Thyroid Cancer, Papillary, Thyroid Neoplasms, Thyroidectomy

BACKGROUND: Perineural invasion (PNI) is associated with aggressive tumor behavior, increased locoregional recurrence, and decreased survival in many carcinomas. However, the significance of PNI in papillary thyroid cancer (PTC) is incompletely characterized.

METHODS: Patients diagnosed with PTC and PNI from 2010-2020 at a single, academic center were identified and matched using a 1:2 scheme to patients without PNI based on gross extrathyroidal extension (ETE), nodal metastasis, positive margins, and tumor size (±4 cm). Mixed and fixed effects models were used to analyze the association of PNI with extranodal extension (ENE)-a surrogate marker of poor prognosis.

RESULTS: In total, 78 patients were included (26 with PNI, 52 without PNI). Both groups had similar demographics and ultrasound characteristics preoperatively. Central compartment lymph node dissection was performed in most patients (71%, n = 55), and 31% (n = 24) underwent a lateral neck dissection. Patients with PNI had higher rates of lymphovascular invasion (50.0% vs. 25.0%, p = 0.027), microscopic ETE (80.8% vs. 44.0%, p = 0.002), and a larger burden [median 5 (interquartile range [IQR] 2-13) vs. 2 (1-5), p = 0.010] and size [median 1.2 cm (IQR 0.6-2.6) vs. 0.4 (0.2-1.4), p = 0.008] of nodal metastasis. Among patients with nodal metastasis, those with PNI had an almost fivefold increase in ENE [odds ratio [OR] 4.9 (95% confidence interval [CI] 1.5-16.5), p = 0.008] compared with those without PNI. More than a quarter (26%) of all patients had either persistent or recurrent disease over follow-up (IQR 16-54 months).

CONCLUSIONS: PNI is a rare, pathologic finding that is associated with ENE in a matched cohort. Additional investigation into PNI as a prognostic feature in PTC is warranted.

Alternate JournalAnn Surg Oncol
PubMed ID36897419
PubMed Central ID6992619
Related Faculty: 
Theresa Scognamiglio, M.D.

Pathology & Laboratory Medicine 1300 York Avenue New York, NY 10065 Phone: (212) 746-6464
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