PCNA--a cell proliferation marker in vocal cord cancer. Part II: Recurrence in malignant laryngeal lesions

Laryngeal squamous cell carcinoma constitutes the most frequent carcinoma found in the head and neck region. A precise prediction for recurrence potential cannot be done on site, treatment and histologic grading. Since Proliferating Cell Nuclear Antigen (PCNA) and DNA-cytometry have shown a good correlation between premalignant lesions and their progressive potential towards full-fledged carcinoma in the larynx as described in part I of this work, we have analyzed the PCNA index and DNA cytometry in specimen taken from vocal chord carcinomas with a 5-year follow-up, in order to assess its relationship with the presence or absence of tumour progression. 42 cases with (21) and without (21) recurrence have been examined. The DNA-index ranged from 1.01 to 1.43 (mean 1.10) in the group without and from 1.02 to 1.59 (mean 1.38) in the group with recurrent carcinoma (p = 0.002). The PCNA-index ranged from 0.00% to 18.90% (mean 6.97%) in the non-recurrent group and from 0.00 to 3g.50% (mean 16.35%) in the patients with recurrence (p = 0.001). Both indices also correlated in a highly significant way. From these data emerges a highly significant correlation between the cytometric indices of cell proliferation and PCNA immunostaining. Furthermore the high correlation between PCNA and DNA-index is of special interest for single case assessment. High DNA aberration and PCNA-index in vocal chord carcinoma may indicate a higher cellular aggressiveness of the tumour, resulting in a greater overall risk of metastases and local recurrences. Our results support the thesis that the indices of cellular proliferation within some cancers can define subsets of patients of high risk and help in isolating a population in which a more aggressive clinical protocol may be proposed.