Hematologic oncology

ALSO KNOWN AS: Blood and bone marrow treatment

DEFINITION: Hematologic oncology is the medical specialty for the diagnosis, treatment, and prevention of disorders and cancerous conditions affecting the blood, bone marrow, and lymphatic system. As defined by the American Society of Hematology, a hematologist is a physician who specializes in the diagnosis, treatment, prevention, or investigation of disorders of the hematopoietic, hemostatic, and lymphatic systems, and disorders of the interaction between blood and the blood vessel wall. Hematologic oncology practices can be found in university medical centers, community hospitals or clinics, specialized cancer hospitals, comprehensive cancer centers, and laboratories.

Subspecialties: Medical oncology/hematology, pediatric oncology/hematology

Cancers treated: Many cancers, particularly leukemia, lymphoma, multiple myeloma, hemophilia, sickle cell disease, thalassemia, aplastic anemia and other anemias, hemochromatosis, Hodgkin disease, marrow failure syndromes, platelet disorders, idiopathic thrombocytopenic purpura, and other thrombotic disorders, and von Willebrand disease and related conditions.

Training and certification: Hematologists may be internists or pathologists who further specialize in disorders of the blood. In addition to having a four-year medical degree from an accredited program and board certification from the American Board of Internal Medicine (ABIM), hematologists complete a one-year internship and three or more years of postgraduate residency training in hematological disorders.

After completing at least three years of training, hematology fellows can take a certification exam in hematology offered by the ABIM or the American Board of Pathology. They become board-certified after passing this exam. Once certified, hematologists often further their training by participating in one or more years of clinical or laboratory research.

Hematologists are trained in the basic science principles and techniques, the pathophysiology of normal and abnormal hematologic processes, and the tools needed to diagnose and manage patients with hematologic disorders. Specific areas of study include basic laboratory concepts and techniques, pharmacology, clinical laboratory techniques, transfusion medicine, radiation therapy, diagnostic imaging, hematopoiesis, red and white blood cell disorders, hemochromatosis, platelet and megakaryocyte disorders, bone marrow failure states, hemostasis, hematologic neoplastic disorders, palliative care, bone marrow transplantation, stem cell transplantation, and hematologic manifestations of infectious diseases.

Hematologic clinical practice guidelines, quality care standards, and quality assurance measures are established primarily by the American Society of Hematology (ASH), a nonprofit organization representing thousands of blood specialists, including scientists, practitioners, educators, and trainees from over ninety countries. The mission of the ASH is to further the understanding, diagnosis, treatment, and prevention of blood disorders by promoting research, clinical care, education, training, and advocacy in hematology.

Services and procedures performed: Treatments provided by a hematologist may include therapeutic phlebotomy, bone marrow aspiration and biopsy, and chemotherapy. Therapeutic phlebotomy removes blood from the circulatory system through an incision or puncture for analysis and diagnosis. Phlebotomy may treat certain blood disorders, such as polycythemia vera, which causes increased red blood cell volume (hematocrit). It may also treat patients with disorders that highly elevate blood iron levels, such as hemochromatosis, hepatitis B, and hepatitis C.

Bone marrow aspiration and core bone marrow biopsy involve removing a bone marrow and fluid sample for analysis. During the bone marrow biopsy procedure, a needle is inserted into the hip bone, and a sample of fluid and bone marrow is withdrawn through the needle into an attached syringe. Ultrasound or computed tomography (CT) may help guide and accurately place the needle. Bone marrow aspiration can also be done to collect bone marrow for medical procedures such as stem cell transplantation or chromosomal analysis.

Chemotherapy is a cancer treatment medication that has a toxic effect on cancer cells. Chemotherapy drugs slow the growth of cancer cells, shrink tumors before other treatments, such as surgery or radiation, or cure a specific cancer.

Related specialties and subspecialties: Hematologists work with a multidisciplinary team of healthcare providers to provide early detection and accurate diagnosis, offer prompt, appropriate state-of-the-art treatment to reduce morbidity and improve quality of life and survival, provide psychological guidance through complex treatment phases, reduce long-term effects of chemotherapy and radiation therapy, and provide long-term follow-up.

Multidisciplinary team members include primary care physicians and other specialists such as medical oncologists, urologic surgeons, orthopedic surgeons, neurosurgeons, diagnostic radiologists, radiation oncologists, infectious disease specialists, pathologists, oncology nurses, physical therapists, oncology social workers, and other allied healthcare professionals, such as educational specialists, registered dietitians, and pharmacologists.

Medical oncologists determine the appropriate systemic or adjunctive drug regimen to treat the patient’s condition and supervise the dosage, schedule, and administration of cancer drugs. They are trained and skilled in chemotherapy drug indications and toxicities, so they can safely administer these therapies with minimal side effects while appropriately managing complications.

Oncologist surgeons use laparoscopy, thoracoscopy, and other surgical techniques to diagnose and treat cancers. These doctors first obtain a four-year medical degree from an accredited program and board certification from the American Board of Surgery. They complete five years of residency training in an accredited general surgery program and at least two years of fellowship training in oncological surgery.

Diagnostic radiologists obtain and interpret medical images to diagnose diseases. They must also have a four-year medical degree from an accredited program and board certification from the American Board of Radiology (ABR) or the American Osteopathic Board of Radiology. They must also pass a licensing examination and complete at least four years of residency training in an accredited radiology program. Radiation oncologists, also known as clinical oncologists, treat cancers using radiation. Most complete an American Council of Graduate Medical Education or ABR-approved residency in radiation oncology.

Infectious disease specialists are physicians who are experts in diagnosing and treating infectious diseases. They obtain a four-year medical degree from an accredited program and board certification from the American Board of Pediatrics. Then, they complete three or more years of residency training and two to three years of additional training in infectious diseases.

Pathologists are physicians who are experts in the pathology of hematologic malignancies and solid tumors and are skilled in immunochemistry and molecular techniques to assess malignancies. In addition to having a four-year medical degree from an accredited program and board certification from the ABIM, pathologists must complete three or more years of residency training and one to two years of additional pathology training.

Oncology nurses administer medications, provide medical care, and educate patients and families. Oncology clinical nurse specialists are registered nurses with a master’s degree in oncology nursing. They prepare and administer medications, including chemotherapy, understand treatment protocols, and have experience in managing treatment complications. Oncology nurse practitioners are registered nurses with a master’s or doctoral degree. The Oncology Nurses Society facilitates the professional development of oncology nurses. 

Bibliography

Abeloff, Martin D. Abeloff’s Clinical Oncology. 6h ed., Elsevier, 2020.

Cavalli, F., et al., eds. Textbook of Medical Oncology. 4th ed. Informa Healthcare, 2009.

Gerçeker, Gülçin Özalp, et al. "The Effect of Virtual Reality on Pain, Fear, and Anxiety During Access of a Port with Huber Needle in Pediatric Hematology-oncology Patients: Randomized Controlled Trial." European Journal of Oncology Nursing, vol. 50, 2021, p. 101886. doi.org/10.1016/j.ejon.2020.101886.

Hastings, Caroline. Handbook of Pediatric Hematology and Oncology: Children’s Hospital and Research Center Oakland. 3rd ed., John Wiley & Sons, 2021.

"Hematologic Oncology Treatment Center." Dana-Farber Cancer Institute, www.dana-farber.org/cancer-care/treatment/blood-disorders. Accessed 10 July 2024.

Hoffman, Ronald. Hematology: Basic Principles and Practice. 8th ed. Elsevier Health Sciences, 2022.

Kantarjian, H. M., et al. The M. D. Anderson Manual of Medical Oncology. 4th ed. McGraw, 2022.