Amelia Morales-Toquero

Extramedullary Leukemic Relapses Following Hematopoietic Stem Cell Transplantation with Nonmyeloablative Conditioning

Of a group of 149 patients who underwent allogeneic stem cell transplantation using the “Mexican approach,” a nonablative preparative regimen, 49 individuals developed bone marrow relapse, and 8 patients developed extramedullary relapse (EMR). All EMR cases presented in patients who received allografts for myeloid malignancies. In contrast, bone marrow relapses presented in patients with myeloid or lymphoid malignancies. EMR presented 60 to 1010 days after the allograft and appeared in 3 cases as subcutaneous nodules in different parts of the body, in the vertebrae in 3 cases, and in the kidney and the breast in 1 case each. One patient had both subcutaneous nodules and epididymis EMR. When EMR was noted, acute graft-versus-host disease (GVHD) had presented in 4 patients, and limited forms of chronic GVHD were present in 3 patients. All but 1 of the patients were full chimeras when the EMR ensued, and the EMR preceded an overt hematologic relapse in all but 1 of the patients. Patients who experienced an overt hematologic relapse died 20 to 180 days (median, 40 days) after the EMR. The only individual alive 240 days after relapse shows no evidence of a full-blown hematologic relapse. An EMR after allogeneic hematopoietic stem cell transplantation usually has a bad prognosis and presents mainly in individuals with high-risk malignancies.Of a group of 149 patients who underwent allogeneic stem cell transplantation using the “Mexican approach,” a nonablative preparative regimen, 49 individuals developed bone marrow relapse, and 8 patients developed extramedullary relapse (EMR). All EMR cases presented in patients who received allografts for myeloid malignancies. In contrast, bone marrow relapses presented in patients with myeloid or lymphoid malignancies. EMR presented 60 to 1010 days after the allograft and appeared in 3 cases as subcutaneous nodules in different parts of the body, in the vertebrae in 3 cases, and in the kidney and the breast in 1 case each. One patient had both subcutaneous nodules and epididymis EMR. When EMR was noted, acute graft-versus-host disease (GVHD) had presented in 4 patients, and limited forms of chronic GVHD were present in 3 patients. All but 1 of the patients were full chimeras when the EMR ensued, and the EMR preceded an overt hematologic relapse in all but 1 of the patients. Patients who experienced an overt hematologic relapse died 20 to 180 days (median, 40 days) after the EMR. The only individual alive 240 days after relapse shows no evidence of a full-blown hematologic relapse. An EMR after allogeneic hematopoietic stem cell transplantation usually has a bad prognosis and presents mainly in individuals with high-risk malignancies.

Non-myeloablative hematopoietic stem cell transplantation is of limited value in advanced or refractory acute myeloblastic leukemia. The Mexican experience †

Abstract Allogeneic hematopoietic stem cell transplantation (HSCT) is an effective strategy for preventing relapse of acute myelogenous leukemia (AML). We analyzed the outcome of 31 primary AML patients who received a reduced-intensity conditioning regimen for allogeneic HSCT in first or second remission. Thirty-one AML patients, 20 in first complete remission (FCR), 8 in second complete remission (SCR) and 3 in a partial remission (SPR) were included. All received busulfan 4 mg/kg/d/2 days, fludarabine 30 mg/m2/d/3 days and cyclophosphamide 350 mg/m2/d/3 days as conditioning regimen. The median number of CD34+ cells infused was 5.6 × 106/kg and 5.2 × 106 in FCR and SCR group, respectively. All patients received cyclosporine-A (CsA) and methotrexate as graft vs. host disease (GvHD) prophylaxis. All patients showed myeloid engraftment (neutrophils >0.5 × 109/l) after a median of 13 days in FCR group and 15 days in SCR group. Platelet recovery >20 × 109/l was achieved after a median of 13 days in both groups. Relapse for 20 patients in FCR was 35% compared to 91% for 11 in SCR/SPR (p < 0.05). Conclusions. Reduced-intensity conditioning followed by allogeneic HSCT can induce stable remission in primary AML patients transplanted in FCR. A high relapse rate was documented in patients with refractory or relapsed AML.

t(8;21) (q22;q22) Acute myelogenous leukemia in México: A single institution experience

Abstract We analyze the prevalence and clinical features of a group of patients with t(8;21) (q22;q22) acute myeloblastic leukemia, identified in a single institution in México over a 10-year period. Fifteen patients presented at the Centro de Hematología y Medicina Interna de Puebla from February 1995 to August 2005; only nine were treated and followed in the institution. Median age was 24 years, (range 7–49); there was only one male. According to the French–American–British (FAB) morphological classification of leukemia, the morphology was M2 in four cases, M4 in three cases, M3 in one case and M0 in one. In addition to the myeloid markers, lymphoid markers were identified in 6 patients. Patients were induced to remission with combined chemotherapy and three subsequently underwent bone marrow transplantation (BMT). The median overall and disease-free survival has not been reached, being above 3390 days, the probability of survival at this time was 73%. In this single-center experience in México, we found that the t(8;21) (q22;q22) variant of leukemia was more frequent than in Caucasian populations, that the co-expression of lymphoid markers in the blast cells is very frequent and that this malignancy is associated with a relatively good prognosis.