Maintenance chemotherapy for up to 3 years is traditionally given to patients with acute lymphoblastic leukaemia (ALL) achieving complete remission. We questioned the value of such maintenance therapy in adult patients treated with intensive induction/consolidation. In a phase II study (SAKK 33/86) 63 patients between 17 and 72 years of age (median 27 years) with newly diagnosed ALL were treated with three intensive cycles of marrow-ablative chemotherapy. All subtypes were included. No maintenance phase was added. 53 patients (84%) entered a complete remission (CR) and 21 (33%) continue to be in unmaintained remission for 11-69 months (median 21 months). The disease-free survival of patients achieving CR and completing all three cycles is 40% at 3 years, with a 95% confidence interval of +/- 19%. These findings are comparable to the results of conventional studies. We conclude that maintenance therapy might not be needed in all adult ALL patients. Its value should be tested in a randomized trial. For patients failing, novel approaches are needed to improve outcome in adult ALL.

Nineteen patients with advanced malignant tumors, less than 20 years old were treated with intensive chemotherapy (vincristine 2 mg/m2 i.v. and adriamycin 60 mg/m2 i.v. on day - 7; cyclophosphamide 45 mg/kg i.v. on days -6 to -3), total body irradiation (TBI, 600 rads on day -1) and autologous bone marrow transplantation (ABMT, day 0). Prior to this procedure induction of complete or partial remission by conventional therapy was attempted. Ten patients had intra-abdominal non-Hodgkin's lymphoma (NHL); three, yolk sac tumor; three, Ewing's sarcoma; and three, neuroblastoma. The supportive care included reverse isolation, immunoglobulin 400 mg/kg i.v. q 2 weeks, cotrimoxazole per os, and cell support as needed. No correlation between the bone marrow dose and the time of hematological reconstitution could be established. Five of seven patients with intra-abdominal NHL stage III (transplanted in first remission) are surviving disease-free for 5+, 5+, 20+, 23+, and 35+ months after ABMT. None of three patients with intra-abdominal NHL stage IV is surviving (two of them were transplanted in second remission). One of three patients with yolk sac tumor is surviving disease-free for 27+ months. There are no survivors among the patients with Ewing's sarcoma and neuroblastoma. Only one of 19 patients was lost due to therapeutic complications, while 12 died due to tumor. Regarding treatment results for advanced intra-abdominal NHL, the procedure described here is comparable to the best conventional regimens. In vitro methods for tumor cell eradication in the collected bone marrow might further improve the results of ABMT.

Elimination of neoplastic B cell populations from autologous bone marrow grafts also removes normal B lymphocytes. This is potentially hazardous for the reconstitution of the immune system in patients undergoing high-dose chemotherapy and total body irradiation followed by autologous marrow rescue. Five pediatric patients with B cell non- Hodgkin's lymphoma in first remission undergoing such a regimen were studied. They received bone marrow pretreated with anti-Y 29/55 monoclonal antibody and complement. B and T lymphocyte subpopulations reached normal levels within 6 months after autologous bone marrow transplantation (ABMT), and serum immunoglobulin levels became normal within 4 to 9 months. Vaccination with diphtheria and tetanus toxoid, trivalent poliomyelitis vaccine of the Salk type, and pneumococcal capsular antigens (38 to 54 months after transplantation) gave rise to specific antibody production. ABO isoagglutinins could be demonstrated in all patients. The response pattern was similar to that of patients who received unmanipulated autologous bone marrow. It is concluded that ex vivo anti-Y 29/55 depletion of the marrow graft does not induce relevant disturbances of humoral immune functions.

Elimination of neoplastic B cell populations from autologous bone marrow grafts also removes normal B lymphocytes. This is potentially hazardous for the reconstitution of the immune system in patients undergoing high-dose chemotherapy and total body irradiation followed by autologous marrow rescue. Five pediatric patients with B cell non- Hodgkin's lymphoma in first remission undergoing such a regimen were studied. They received bone marrow pretreated with anti-Y 29/55 monoclonal antibody and complement. B and T lymphocyte subpopulations reached normal levels within 6 months after autologous bone marrow transplantation (ABMT), and serum immunoglobulin levels became normal within 4 to 9 months. Vaccination with diphtheria and tetanus toxoid, trivalent poliomyelitis vaccine of the Salk type, and pneumococcal capsular antigens (38 to 54 months after transplantation) gave rise to specific antibody production. ABO isoagglutinins could be demonstrated in all patients. The response pattern was similar to that of patients who received unmanipulated autologous bone marrow. It is concluded that ex vivo anti-Y 29/55 depletion of the marrow graft does not induce relevant disturbances of humoral immune functions.

No abstract