Objective: To investigate the factors on distant metastases (DM) of laryngeal cancer.
Methods: 277 cases of laryngeal cancer hospitalized in Cancer Center of Sun Yat-sen University from 1990 to 1995 were reviewed. 18 cases with DM were investigated to confirm the distant metastatic rate, target organ, time interval, and prognosis. Kaplan-Meier and Cox model analysis were used to find the significant indicators for DM in laryngeal cancer.
Results: The overall incidence of DM in laryngeal cancer was 6.5% (18/277). The target site of DM was mainly in lung 83.3% (15/18), liver 16.7% (3/18). 3 cases with DM in lung also combined with bone metastases which occurred in vertebra 1, lib 1 and 1 in multi-sites. 2 patients were diagnosed DM when admitted, and the rest with time interval between 1 and 103 months (median 7 months). The 3-year and 5-year cumulative survival in laryngeal cancer with DM was 23.8% and 11.9% respectively. The time interval between the presentation of DM and death was 2.77 months (median 4.6 months). The worst prognosis is liver metastasis with which the patient could survive 4.6 months at most in our study. Kaplan-Meier analysis in 277 laryngeal cancers showed that pathology, pathological differentiation of squamous cell carcinoma, N stage, and clinical stage were significant indicators for DM from laryngeal cancer. Cox model analysis showed that only N stage was the significant prognostic factor for DM in laryngeal cancer (Wald = 7.889, P = 0.005).
Conclusion: Laryngeal cancer has certain percentage of DM, which is mainly in lung and their prognosis is usually poor. Non-squamous cell carcinoma, low pathological differentiation, cervical metastasis and advanced cancer are the possible indicators for DM, but our study shows that only N stage significantly predicts DM from laryngeal cancer.