The five parameters including nuclear area (NA), nuclear perimeter (NP), nuclear diameter (ND), axis ratio and nuclear roundness were evaluated with MIAS200 Image Analysis System (Sichuan University, Chengdu) in 45 patients with laryngeal primary squamous cell carcinoma, which were confirmed pathologically and operated on from January 1977 to October 1987. The results showed that NA, NP and ND are important prognostic indicators. The survival rate in patients with large nuclei (NA greater-than-or-equal-to 73-mu-m2, NP greater-than-or-equal-to 32.5-mu-m, ND greater-than-or-equal-to 12-mu-m) was significantly lower than that in those with small nuclei (NA < 73-mu-m2, NP < 32.5-mu-m, ND < 12-mu-m) (P < 0.0025). These findings strongly suggest that patients with laryngeal squamous cell carcinoma with large nuclei should be treated more aggressively.