Adjuvant treatment of canine osteosarcoma with the human cytotoxic T-cell line TALL-104

The human cytotoxic T-cell line TALL-104 has been used successfully to trea t cancer in experimental mouse models with implanted tumors and in dogs wit h spontaneously occurring malignancies. This study investigated the efficac y of TALL-104 cells given in an adjuvant setting to dogs with appendicular osteosarcoma after surgery and chemotherapy. Of the 23 dogs enrolled in the study, 20 had undergone amputation of the affected limb, and 3 had undergo ne limb salvage surgery. After surgery, all dogs but one received cisplatin (CDDP) chemotherapy (60 mg/m(2) i.v. every 21 days x 1-4 cycles). Four dog s also received one to six cycles of CDDP before limb amputation. After CDD P therapy, dogs without overt metastasis received gamma-irradiated (40 Gy) TALL-104 cells systemically (10(8)/kg) for 5 consecutive days, followed by 2-day monthly boosts (at the same dose) for a total of 9 months, Of the 23 dogs treated, 9 survive disease-free at 12.1-29.5 months after surgery, 11 died of metastatic disease between 5 and 21.5 months, 1 experienced a relap se in the lung 9.5 months after surgery but is still alive without further treatment at 13 months, 1 developed severe discopathy at 4 months after sur gery, and 1 developed progressive neuropathy at 5.9 months after surgery. T he overall median survival time is 11.5 months, and the median disease-free interval is 9.8 months. Our cell therapy results compare favorably with hi storical median survival times (up to 9 months) and disease-free intervals (up to 7.5 months) of dogs with osteosarcoma receiving standard therapy (su rgery and chemotherapy) and support the effectiveness of adjuvant TALL-104 cell administration in preventing or delaying disease recurrence in these d ogs.