Papaya leaf has shown to increase platelet count. The Platelet Disorder Support Organization (www.pdso.org) provides the following information:
Low Platelets Associated with Cancer:
for many types of cancer can damage the bone marrow and result in a low platelet count. However, there are some cancers that have a more direct association with thrombocytopenia due to bone marrow involvement, compromised immune system, or an enlarged spleen. Someone with cancer usually has other symptoms in addition to low platelets.
Myelodysplastic Syndrome (MDS)
Blood cells are produced in the bone marrow. In MDS the bone marrow is damaged and blood cell production is impaired, including platelets. The disease can transform into acute myelogenous leukemia (AML)
Chronic Lymphocytic Leukemia (CLL)
In CLL there is a gradual increase in the B-cells, a type of white blood cell, and eventually bone marrow failure. You can get ITP in addition to CLL
CD8 T-lymphocyte large granular lymphocytic leukemia (LGL)
This diseases is a rare form of leukemia characterized by abnormal CD8+ T cells, a type of white blood cell.
Refer to the following study related to low platelet count (specifically Dengue) and papaya leaf: