Assessment of thyroid cartilage ossification pattern in cancer patients: A suggestion of active ossification by tumor progression.

Background: Ossified cartilage is much more susceptible to cancer infiltration, but the reason remains unknown, and the relationship between the ossification pattern and cancer infiltration has not been studied. Methods: The presence of thyroid cartilage ossification, cancer infiltration, ossification pattern (usual: direction from inferior to superior; unusual: other than the usual pattern), and distance between cancer and ossified cartilage were evaluated in laryngectomy specimens. Results: There were 28 and 27 cases of usual and unusual patterns, respectively. There was no association between ossification pattern and cancer infiltration. However, the distance between the ossified area and cancer cells was greater in the usual pattern than in the unusual pattern (p = 0.006). And the usual pattern was more frequently observed in cases with a distance >1 mm than in cases with cancer infiltration or a distance ≤1 mm (p = 0.004). Conclusion: These results suggest the possibility of an active ossification due to tumor progression. [ABSTRACT FROM AUTHOR]