Collagen matrix cisplatin prevents local tumor growth after margin-positive resection

The extent of a tumor, sometimes combined with its anatomic location, can compromise the surgeon's ability to obtain clear margins of resection. Regional recurrence of a tumor in the resection bed frequently produces significant local morbidity and limits patient survival time and quality of life. A positive margin resection model was created by induction of perinephric VX-2 tumors in New Zealand white rabbits followed by unilateral nephrectomy with grossly positive margins in the retroperitoneum. Resection bed injection of a novel collagen matrix with cisplatin (CDDP) and epinephrine prevented tumor recurrence in all treated animals. In contrast, control animals treated with CDDP alone, CDDP and epinephrine alone, or the collagen matrix with epinephrine had bulky tumor recurrence in the resection bed. Resection bed tissue levels of platinum were determined by flameless absorption spectrophotometry at 1, 4, and 7 days following nephrectomy and injection of the collagen matrix, CDDP, and epinephrine or CDDP and epinephrine without the collagen matrix. Significantly higher resection bed drug levels of platinum were achieved through the use of the novel collagen matrix than through the use of CDDP and epinephrine alone (P < 0.05). The results of this study indicate that tumor bed treatment with CDDP and a unique collagen matrix drug-delivery vehicle produces prolonged high resection bed levels of platinum and prevents local tumor recurrence.