Receptors for epidermal growth factor and steroid hormones in primary laryngeal tumors. The authors investigated the presence of epidermal growth factor (EGF-R), estrogen (ER), progesterone (PR), and androgen (AR) receptors in 42 laryngeal squamous cell carcinomas and 20 normal laryngeal mucosa specimens. EGF-R were expressed in all tumor specimens analyzed, with significantly higher levels in tumor samples compared with normal mucosa (P less than 0.05). The immunohistochemical study demonstrated the presence of EGF-R in basal and parabasal cells of normal mucosa and in most of the cancer cells. There was no correlation between EGF-R and tumor localization or T classification. On the other hand, the authors did find an interesting correlation between EGF-R levels and grading, EGF-R levels being significantly higher in G3 than in G1-G2 tumors. Moreover, the three patients whose tumors expressed the highest EGF-R levels had disease recur within 8 months. Among tumor specimens, 9.5%, 35.7%, and 9.5% expressed very low but detectable ER, PR, and AR levels, respectively. No statistically significant difference was found between the levels of steroid receptors in the tumor and normal mucosa specimens, and neither was there any correlation of ER, PR, and AR with the pathologic findings. The authors' results suggest that the EGF-R system may play a role in regulating the growth of laryngeal cancer. Additional studies should demonstrate whether, as in other tumor types, EGF-R expression may have prognostic significance in human laryngeal cancer. 