INTRODUCTION
Hodgkin Lymphoma (HL) is one of the most prevalent tumors (9%) treated at the Association of Pediatric Hematology-Oncology of Central America (AHOPCA), a childhood cancer network of pediatric cancer centers from Central America, Dominican Republic, and Haiti1. This network designs uniform treatment guidelines, for children with cancer diagnosed at the individual centers. Over time, AHOPCA has studied baseline treatment outcomes for different pathologies in the region, and has addressed unique psychosocial needs in low- and middle income countries (LMIC)1,2. Because radiation therapy is not easily accessible in every country in Central America, the AHOPCA Center in Nicaragua designed a chemotherapy only regimen consisting of four cycles of cyclophosphamide, vincristine, prednisone and procarbazine (COPP) for patients with early stage HL and two to four additional courses of chemotherapy consisting of doxorubicin, bleomycin and vinblastine (COPP/ABV) for advanced stage HL3. Based on encouraging results for this regimen, AHOPCA implemented a chemotherapy-only treatment guideline4: AHOPCA LH-1999 using the same risk assessment and treatment schema for all subjects presenting to an AHOPCA Center. Castellanos et al reported an event-free survival (EFS) of 60% regardless of risk assignment4. However, the EFS for patients with Ann Arbor stage IV HL was only 20%. This report identified two critical factors that influenced the poor outcomes: abandonment of therapy (13%), accuracy of diagnosis and appropriate staging4.
To improve survival, improve diagnostic accuracy and reduce abandonment, AHOPCA introduced in 2004 three risk groups, low, intermediate, and high with strict staging and risk assignment criteria, response assessment and clear radiation therapy guidelines. AHOPCA hypothesized that a regimen that could be administered over a short period of time (to prevent abandonment), that had an established low toxicity profile with lower anthracycline dose (150mg/m2), and low infertility5, would be effective in a resource-limited setting. Based on the excellent results reported with the Stanford V regimen5 6, a short 12-week course of chemotherapy with doxorubicin, vinblastine, vincristine, bleomycin, etoposide, prednisone and mechlorethamine and 36 Gy radiotherapy to bulky sites of disease (> 5cm) at diagnosis. AHOPCA adopted this regimen as a treatment guideline for children presenting with pre-defined high-risk HL (HRHL). In 2004 there was a world-wide shortage of merchlorethamine7, leading AHOPCA to modify the treatment regimen substituting merchlorethamine with cyclophosphamide at a dose that was expected to be an equipotent substitution. Furthermore, radiation therapy was modified to (20-25 Gy) involved field in order to limit radiation-related long-term effects8-10. We report here the experience of AHOPCA with this regimen, AHOPCA HRHL 2004 (mStanford V), as applied between August 2004 and August 2009.