Small intestinal submucosa does not promote PAIII tumor growth in Lobund-Wistar rats.
BACKGROUND
Site-specific remodeling and angiogenesis are two observations associated with the use of small intestinal submucosa (SIS) as a tissue repair graft. Its angiogenic capacity has raised questions concerning its effect on tumor growth and metastasis in clinical tumor resection cases. The effect of SIS on the ability of neoplastic (prostate adenocarcinoma) cells to establish, grow, and metastasize was examined in Lobund-Wistar (L-W) rats.


METHODS
In one study, SIS, expanded polytetrafluoroethylene (ePTFE), or human cadaveric dermis was placed in a subcutaneous pocket on the flank of L-W rats and immediately inoculated with PA-III cell suspension. Tumors were allowed to establish and metastasize for 5 weeks prior to sacrifice. Rate of tumor growth, tumor weight, and frequency of lung metastases were assessed. In a second study, SIS was placed in a resected tumor bed and tumors were allowed to recur. Rate of tumor growth, tumor weight, and frequency of lung metastases were assessed after 3 weeks.


RESULTS
ePTFE hastened the rate of formation of palpable tumors compared to controls and other materials; cadaveric dermis and SIS did not. No differences between materials were noted in final tumor weight nor in the frequency of metastasis to the lungs. Following surgical tumor resection, residual tumor cells led to recurrence of same-site tumors in all animals, but in the defects augmented with SIS, the tumors were significantly smaller than those which regrew in the resected, unaugmented group.


CONCLUSIONS
This study demonstrates that SIS does not enhance tumor establishment, growth, or metastasis in de novo tumors. Furthermore, SIS appears to reduce the rate of tumor growth, but not metastasis, when applied in direct contact with a residual tumor bed in a rat model of prostate-related tumors.
Hodde
Jason P
JP
Cook Biotech Incorporated, 3055 Kent Avenue, West Lafayette, Indiana, USA. hodde@cookbiotech.com
Suckow
Mark A
MA
Wolter
William R
WR
Hiles
Michael C
MC
D000230:Adenocarcinoma / Q000473:pathology* / Q000503:physiopathology* / Q000556:secondary / Q000601:surgery; D000818:Animals; D001672:Biocompatible Materials; D002455:Cell Division; D003094:Collagen; D006801:Humans; D007413:Intestinal Mucosa / Q000503:physiopathology*; D007421:Intestine, Small / Q000503:physiopathology*; D008175:Lung Neoplasms / Q000473:pathology / Q000556:secondary; D008297:Male; D009364:Neoplasm Recurrence, Local / Q000473:pathology; D009368:Neoplasm Transplantation; D011138:Polytetrafluoroethylene; D011471:Prostatic Neoplasms / Q000473:pathology* / Q000503:physiopathology* / Q000601:surgery; D051381:Rats; D017208:Rats, Wistar
C440568:Alloderm; D001672:Biocompatible Materials; D011138:Polytetrafluoroethylene; D003094:Collagen