Blood cancer, also known as hematologic cancer, affects the blood, bone marrow, and lymphatic system. The main types include leukemia, lymphoma, and myeloma. These cancers disrupt the normal production and function of blood cells, leading to various health issues such as anemia, infections, and bleeding problems. Symptoms of blood cancer can vary but often include fatigue, unexplained weight loss, fever, and swollen lymph nodes. Diagnosis typically involves blood tests, bone marrow biopsies, and imaging studies. Treatment options may include chemotherapy, radiation therapy, and stem cell transplants, depending on the specific type and stage of the cancer.