Clinical aspects of transplantability of human gastric and colorectal carcinomas in nude mice

Transplantability of human tumors into nude mice might represent higher grade of malignancy. In our institution, surgically resected tumors have been subjected to transplantation into nude mice since 1975. We retrospectively investigated clinical outcomes of donor patients with gastric and colorectal cancer who underwent operation and analyzed the relationship between the transplantability and clinical characteristics of the patients. Thirty five out of 119 gastric tumors were successfully transplanted into nude mice with a 29.4% take rate. Results of transplantation among 92 patients' tumor in stage 2, 3 and 4 revealed 35 takes and 57 non-takes. There were only 3 ten-year survivors in the 'take' group while there were 17 ten-year survivors in the 'non-take' group. Patients with tumors which are transplantable into nude mice appeared to have poor prognosis (p < 0.05). The take rate with fifty colorectal tumors was 50%. Among 46 patient's tumors in stage 2, 3 and 4, there were 25 takes and 21 non-takes. Ten-year survivors included 11 'take' donors and 7 'non-take' donors. As opposed to gastric cancers, no statistically significant difference in survival was observed between the two groups.