M. Nakayama et Jh. Brandenburg, CLINICAL UNDERESTIMATION OF LARYNGEAL-CANCER - PREDICTIVE INDICATORS, Archives of otolaryngology, head & neck surgery, 119(9), 1993, pp. 950-957
Objective: To evaluate the accuracy of clinical staging of advanced la
ryngeal cancer and to morphologically analyze the underestimated cases
. Design: We conducted a retrospective histopathologic study of laryng
es from patients who had had total laryngectomy and were seen over a 2
1-year period. Settings: Academic tertiary referral medical center. Pa
rticipants: Forty-one patients had clinically staged T3 laryngeal canc
er and 16 patients had T4 cancer. Intervention: Patients all underwent
wide-field total laryngectomy. All larynges were processed as whole-o
rgan serial sections in the coronal plane. Outcome Measure: The incide
nce of clinically underestimated laryngeal cancer. During this investi
gation, it became obvious that predictive indicators of thyroid cartil
age involvement could be established. Results: Clinical underestimatio
n 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 adjace
nt 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 cance
r (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 laryngea
l cancer was high because thyroid cartilage involvement was not accura
tely diagnosed. We believe our indicators of thyroid cartilage involve
ment will provide objective guidelines for laryngeal cancer staging an
d will contribute to more reliable clinical cancer-staging decisions.