CHENNAI: Over the last 2 decades, there has been considerable progression in the treatment of the most dreaded blood cancer with survival rates ranging from 60 to 80 per cent in various subtypes.
There are 2 types of blood cancers – acute leukemia and chronic leukemias. Acute leukemia can be lymphoid or myeloid. With the progress in various chemotherapy regimens, the cure rate in pediatric acute lymphatic leukemia has been as high as 80 to 90 per cent in western literature, but the numbers are lower in our country, it is around 60 to 80 per cent.
Doctors say that there are various reason for this starting from delay in diagnosis, to higher infection rates to disease biology and pharmacogenetics. However, acute myeloid leukemia has lower cure rates with chemotherapy alone and a large subset of these patients need a bone marrow transplant as a curative treatment option.
“Bone marrow transplant (BMT) was not easily available in our country 10 years ago, but now there are more than 100 transplant centers in the country who can offer this treatment. It needs a donor to donate the stem cells and generally siblings tend to be the fully matched HLA eligible to donate. However, not all patients would have fully matched sibling donors and hence medical science started looking for other donor options. The stem cell registries were set up and they were able to offer the option of unrelated matching stem cell donors,” said Dr Sharat Damodar, Clinical Director and Head of adult haematology, BMT and Immunotherapy, Mazumdar Shaw Cancer Center, Narayan Health City.
“Adults between the age group of 18 to 60 years can enroll in these registries voluntarily and donate stem cells when needed. Due the non-availability of fully matched donors the next option was to use a half matched parent, child or sibling called a haplo transplant and this is the new therapy for leukemias who need BMT as a curative option,” added Dr Sharat.
However, in spite of all these advances there are patients who cannot undergo BMT or relapse. Only 30 per cent patients who need transplants have a fully HLA matched donor in their family, rest of them depend on an unrelated donor. “A successful blood stem cell transplant depends on a perfect HLA tissue match,” says Dr Sunil Bhat, Director and Clinical Lead, Pediatric Hematology, Oncology and Blood & Marrow Transplantation.