TALL-CELL VARIANT OF PAPILLARY THYROID-CANCER - DISREGARDED ENTITY

The tall-cell variant of papillary thyroid carcinoma (TCV) has been de scribed as an aggressive tumor with a significantly higher incidence o f recurrence and mortality than other forms of papillary carcinoma. In some series it has accounted for up to 10%, whereas in other series i t has not been reported at all, indicating that there are difficulties identifying it, In a series of 162 consecutively treated patients wit h papillary thyroid carcinoma treated by total thyroidectomy according to a highly standardized procedure, all specimens were specifically e xamined by an international group of pathologists to establish the occ urrence of TCV, All patients with TCV were studied with regard to loca l aggressiveness, the presence of metastases, iodine uptake, DNA patte rn, thyroglobulin production, treatment (surgical and adjuvant), and o utcome (follow-up 3-17 years, median 10 years), At primary histopathol ogic evaluation by the local pathologist, three patients were recorded as having TCV, At special evaluation by the expert group, eight more cases were found, giving a total of 11 patients in this series (7%), F ive of them had extracapsular growth, and four were multifocal, Three had metastases at the time of admission. Seven tumors were diploid, on e tetraploid, and three aneuploid, Of the three patients with primary distant metastases two died (8 and 24 months after operation), and one is still alive after 10 years, Four other patients developed recurren ces, one of whom died from cardiac failure, but the others have so far been treated successfully, Two of these recurrences had no radioiodin e uptake, and one had no rise in thyroglobulin concentrations; the oth er two had rising values that correlated with recurrence, The other fo ur patients are alive without recurrence. It,vas concluded that identi fication of the TCV requires examination by an experienced pathologist . Moreover, it may have a higher incidence than is generally recognize d, No reliable criteria for prognostic classification were identified, The results suggest that early identification and active treatment ca n lead to an outcome more favorable than has previously been described .