A cholangiocellular carcinoma nude mouse strain showing histologic alteration from adenocarcinoma to squamous cell carcinoma.

BACKGROUND

Adenosquamous carcinoma and squamous cell carcinoma (SCC) occur rarely in the liver compared with adenocarcinoma, and the histogenesis and biologic behaviors of these tumors remain unknown. The authors addressed these issues in the current article.

METHODS

A specimen aseptically obtained from the surgically resected cholangiocellular carcinoma (CCC) was cut into pieces and inoculated into the back of a nude mouse, bilaterally. The developed tumors were resected and serially transplanted into nude mice. The morphologic features and growth kinetics of the nude mouse tumors at different passages were compared.

RESULTS

The authors established a new human CCC nude mouse strain, designated nuKMC-2, from a 64-year-old woman. The original tumor of the patient showed the features of moderately differentiated tubular adenocarcinoma with small sheet-like arrangement of polygonal cells. The initial tumor developed in a nude mouse showed morphologic features similar to the original tumor. With the serial transplantation to nude mice, the components of tubular adenocarcinoma diminished, and all of the nuKMC-2 was replaced by SCC. Doubling times of nuKMC-2 at the 5th and 11th passages were 9.9 and 7.4 days, respectively, which suggested that the tumor with squamous components were more aggressive biologically than the adenocarcinoma.

CONCLUSIONS

The results suggested that adenosquamous carcinoma might be a transitional form from adenocarcinoma to SCC and that some of the primary hepatic SCC might originate from adenocarcinomas.