Cribriform Adenocarcinoma of the Tongue: Characterization of a New Entity.
Alena Skalova, Roderick HW Simpson, Ilmo V Leivo, Petr Mukensnabl, Michal Michal. Charles University, Faculty of Medicine, Plzen, Czech Republic; Royal Devon and Exeter Hospital, Exeter, United Kingdom; Haartman Institute, University of Helsinki, Finland
Background: In 1999, we have described 8 cases of an unusual carcinoma of the tongue that resembled solid and follicular variant of papillary carcinoma of the thyroid, and we coined the name “cribriform adenocarcinoma of tongue” (CAT). It is currently debated whether CAT is a distinctive tumor type or merely a morphological variant of polymorphous low-grade adenocarcinoma (PLGA). Here we present a new series of 21 tumors with histomorphological features of CAT in order to better characterize a poorly recognized entity.
Design: The 21 patients comprised 12 men and 9 women, with a mean age of 61 years (range 37-88). Most tumors presented with a mass in the tongue (13) or in the tonsils (2), followed by palate (4), and one each was located in the lip and retromolar buccal mucosa. The mean size of the tumors was 2.6 cm (range 2.1 to 4.5 cm). In three patients, the primary site was unknown and first clinical manifestion was cervical lymph node metastasis. Together, 15 patients presented with cervical lymph node metastasis at the time of diagnosis. Clinical follow-up was available in 15 cases, and ranged from 1 to 13 years.
Results: Microscopically, the tumors have a lobulated growth pattern with intervening bands of compressed fibrovascular stroma. Interspersed in the solid parts areas are sheets with compressed tubulo-glandular, microcystic and cribriform structures. The bland looking vesicular nuclei are large with frequent small single nucleoli and considerable nuclear overlapping. The most striking cytological characteristics are pale-staining nuclei with ground-glass appearance resulting in resemblance to solid and follicular variant of papillary thyroid carcinoma.
Conclusions: The evidence favoring CAT as a separate tumor entity from PLGA can be derived from the facts that CAT originates almost exclusively in the base of tongue, it has a typical morphology and extensive clear or “ground glass” nuclear features. Furthermore PLGA shows a much more diverse range of architectural patterns than CAT. None of the described patients and other potential candidates in the literature have died of disease despite the fact that most presented with unilateral or bilateral neck lymph node metastases. It is likely that CAT is a tumor with early lymphotropic metastases into the regional lymph nodes, but in spite of this it has an excellent prognosis.
Category: Head & Neck
Tuesday, March 1, 2011 9:15 AM
Platform Session: Section G, Tuesday Morning