Survival of Hematopoietic Stem Cell Transplantation in the National Institute of Neoplastic Diseases, Lima-Perú between 2012 to 2022: 10 Years of Experience

Introduction:

Hematopoietic stem cell transplantation (HSCT) is part of standard treatment in a great number of hematologic malignancies and some solid tumors. The National Institute of Neoplastic Diseases (INEN) started the HSCT program in 2012, performing over 600 HSCT so far. In this study, we report the overall survival (OS) at 5 years of patients who undergone this procedure in our institution through 10 years of experience.

Methods:

We analyzed retrospectively the survival of all patients admitted to the HCST program at INEN between 2012 and 2022. Clinical and pathological data were collected from the medical records and the unit's transplant patient registry. The OS was determined through the Kaplan-Meier method and the comparisons of survival curves were performed using the log-rank or Breslow test.

Results:

During the study period, a total of 647 transplants were performed. The median age was 39 years (range: 1 - 70), 73.4% of patients were between 18 and 60 years, and 57.1% were men.

Most transplants (n = 591, 91.3%) were performed in the adult population and 8.6% (n = 56) in pediatric population. According to the type of transplant, 68% (n=440) were autologous and 32% (n=207) allogeneic from related donor.

The most frequent diagnosis were acute leukemia (n = 221, 34.2%), multiple myeloma (n = 190, 29.3%), non-Hodgkin lymphoma (n = 105, 16,2%; of these, 22 were T- cell lymphomas), Hodgkin lymphoma (n = 69, 10.7%) and germinal cell tumor (n = 33, 5.1%); in the pediatric population, leukemia was the most common diagnosis (66.1%).

The median follow-up of the patients was 3.7 years (95% CI: 3.4, 3.9), 25.2% (n = 163) of the patients died due to disease progression. The median overall survival (OS) for the entire cohort was not reached and the OS rate at 5 years was 68.3%. The 5-year OS rate by transplant subtype was 53.9% and 75.3% (p < 0.001) for allogeneic and autologous transplants, respectively; and according to the pathology, the patients who had a better 5-year OS were HL (87.5%) and NHL (77.5%), while in leukemias it was 56.1%. Survival by age group (<40 vs >40) and sex (female vs. male) did not present a significant difference (p > 0.05).

Conclusions:

The survival of the transplanted patients was similar to that reported in other series. Leukemia was the most frequent hematological malignancy admitted to the HSCT program. HL and NHL were the malignant tumors with the highest survival rates at 5 years. Nearly a third of transplants were allogeneic, all from matched related donors. HSCT in our series has shown an improvement in OS at 5 years in both autologous and allogeneic transplant patients compared to non-transplanted patients, according to international reports.