Pathologic spectrum of lymphocytic infiltration and recurrence of papillary thyroid carcinoma

The aim of this study was to investigate the prognosis of papillary thyroid carcinoma (PTC) patients according to different pathologic grades of lymphocytic thyroiditis (LT).

This study included 144 PTC patients who underwent total thyroidectomy with radioactive iodine remnant ablation therapy. Pathologic grades of LT were separated at two points, chronic lymphocytic thyroiditis (CLT) and Hashimoto thyroiditis (HT). Patients were divided into two groupings according to the presence of the diseases (Grouping 1; patients with CLT or HT and without CLT or HT, Grouping 2; patients with HT and without HT). The groupings were compared according to recurrence, clinicopathologic and ultrasound (US) characteristics, and disease free survival.

Of 144 patients, 41 had CLT and 19 had HT. There were 10 patients (6.9%) with tumor recurrence. In both groupings, the presence of calcification was more frequently associated with patients with LT (p=0.041 and 0.047, respectively). In Grouping 2, the mean age at diagnosis was older in patients without HT compared to patients with HT (p=0.032). On multivariate analysis, the presence of LT was not an independent predictor of recurrence in both groupings. For both groupings, pathologic tumor size and taller than wide shape on US were independent predictors of recurrence. The presence of LT in PTC patients did not affect recurrence.

There was no relationship between PTC prognosis and different grades of LT. Pathologic tumor size and taller than wide shape on ultrasound were independent predictors of PTC recurrence regardless of concurrent LT.