Clinical underestimation of laryngeal cancer. Predictive indicators
M. Nakayama and J. H. Brandenburg
Department of Surgery, University of Wisconsin, Madison.
OBJECTIVE: To evaluate the accuracy of clinical staging of advanced
laryngeal cancer and to morphologically analyze the underestimated cases.
DESIGN: We conducted a retrospective histopathologic study of larynges from
patients who had had total laryngectomy and were seen over a 21-year
period. SETTING: Academic tertiary referral medical center. PARTICIPANTS:
Forty-one patients had clinically staged T3 laryngeal cancer and 16
patients had T4 cancer. INTERVENTION: Patients all underwent wide-field
total laryngectomy. All larynges were processed as whole-organ serial
sections in the coronal plane. OUTCOME MEASURE: The incidence of clinically
underestimated laryngeal cancer. During this investigation, it became
obvious that predictive indicators of thyroid cartilage involvement could
be established. RESULTS: Clinical underestimation had been made in
approximately 50% of all T3 laryngeal cancer cases. The extent of the
cartilage involvement in the underestimated group was characterized by
microinvasion without penetration; approximately 90% of the cartilage
involvement affected the thyroid notch and adjacent area. We established
five objective indicators of thyroid cartilage involvement: (1) extensive
cartilage ossification (risk for cartilage involvement, 73%); (2) glottic
fixation (54%); (3) transglottic cancer (74%); (4) tumor length longer than
the entire vocal fold length or longer than 2 cm (66%); and (5) extensive
involvement of the anterior commissure (67%). CONCLUSIONS: Clinical
underestimation of T4 laryngeal cancer was high because thyroid cartilage
involvement was not accurately diagnosed. We believe our indicators of
thyroid cartilage involvement will provide objective guidelines for
laryngeal cancer staging and will contribute to more reliable clinical
cancer-staging decisions.
