Peritumoral edema associated with metastatic brain tumor

Computed tomographic (CT) examinations were performed in 94 lesions of 50 patients with metastatic brain tumors. Peritumoral edema (AE) and tumor area (AT) were measured using the planimetric method on the CT scan films that demonstrated maximum size of the tumor. Then, the volume of the peritumoral edema (VE) and the surface area of the tumor (ST) were claculated from these data. Eighty-three brain lesions from lung cancers were subdivided into 49 adenocarcinomas, 11 squamous cell carcinomas, 16 small cell carcinomas and 7 large cell carcinomas. Eleven metastatic tumors from breast cancers were all adenocarcinomas. There was statistical correlation between the surface area of tumor and the volume of the peritumoral edema for the adenocarcinoma (r=0.4043, p<0.01), the squamous cell carcinoma (r=0.6057, p<0.05), the small cell carcinoma (r=0.5055, p<0.05), the large cell carcinoma (r=0.8566, p<0.05) and the breast cancer (r=0.6905, p<0.05). Metastatic tumors adjacent to the ventricular systems showed little peritumoral edema. The VE/ST ratios in small cell carcinomas were smaller then those in non-small cell carcinomas, when the volume of the tumor was larger than 10 mm3. Accordingly, we suggest that the volume of the peritumoral edema in the small cell carcinoma is generally smaller than that in others. (author)