Margaret Mary Showel, M.D.
September 15, 2020
Johns Hopkins Kimmel Cancer Center medical oncology services at Sibley Memorial Hosptial include comprehensive leukemia care — providing patients with access to clinical trials for upfront treatment and recurrent or refractory leukemia; various maintenance therapy options; Johns Hopkins’ bone marrow transplant program; and a nine-bed hematologic malignancy inpatient service.
The Kimmel Cancer Center is also a national leader in haploidentical transplantation, offering patients a greatly expanded pool of bone-marrow donors.
For complex cases, a panel of multidisciplinary experts from throughout the Johns Hopkins system helps determine the best path of care, which is delivered in Washington, D.C.
“The big thing about leukemia is these cases are emergencies and require urgent care,” says Sibley hematologic oncologist Margaret Showel. “We’re available 24/7 to admit patients and start treatment. We have all these resources available and are ready to go here at Sibley.”
The Haploidentical Transplant Program and Clinical Trial Access
For eligible patients, the haploidentical donor program for bone-marrow transplant uses half-matched relatives rather than hard-to-find full matches or unrelated donors. This broadly expands the donor pool, and outcomes are comparable to those of full-match transplants, Showel says.
A portion of the pre- and post-transplant care is provided in the greater Washington, D.C., area, and transplants are performed at the Kimmel Cancer Center’s Bone Marrow Transplant Center in Baltimore, which performs around 350 transplants each year. Johns Hopkins has performed more than 600 haploidentical transplants for adult and pediatric leukemia and lymphoma since developing the procedure more than 10 years ago.
Since leukemia can be aggressive and can relapse in a short period of time, Showel, who is also a transplant coordinator, says time is of the essence in bone marrow transplants.
For patients who relapse after transplant, a situation for which there are limited options, the Kimmel Cancer Center at Sibley offers a number of clinical trials:
- CAR-T cell therapy involves genetically modifying a patient’s own T cells to recognize a specific target on B-cell lymphocytes and then reinfusing the T cells into the patient.
- Donor lymphocyte infusions (DLI) involves the transfusion of donor white cells into patients.
- Adoptive T Cell therapy involves retrieving marrow infiltrating lymphocytes (MILs), which are a kind of T-cell found in cancerous marrow, from patients and reinfusing them after coating them with immune-activating antibodies.
While these and other clinical trials are offered for recurrent and refractory leukemia, these therapies are increasingly being used in upfront settings as well.
“These drugs are improving outcomes and they’re often not as toxic,” says Showel, who is also an assistant professor of oncology at the Johns Hopkins University School of Medicine. “We have more and more upfront trials now and access to drugs that you don’t normally have access to because they’re trial drugs. That’s only going to increase.”
With leukemia’s high rate of relapse, maintenance therapy plays a prominent role in keeping patients in remission. At Kimmel, these trial treatments, which can be molecularly targeted, immunotherapies or differentiating agents, are often integrated with bone marrow transplants.
For those who require an inpatient stay, the nine-bed hematologic malignancy inpatient unit at the Kimmel Cancer Center at Sibley is staffed by a hematologic malignancy specialist, a pharmacist that specializes in hematologic oncology, a hematopathologist, and nurses who are oncology-certified and have hematologic malignancy training. This service, which admits 280 patients annually, allows patients to be seen urgently and for treatment, including apheresis, to start overnight.
Physicians can refer patients to the Kimmel Cancer Center at Sibley with or without a confirmed diagnosis of leukemia, Showel says.
“Some patients need to be seen right away, and we’re happy to see those patients,” she says. “Often we just need to look at a peripheral blood smear to make a diagnosis. We can do that in the middle of the night and start treatment. Those patients in need of urgent care can be referred to us right away.”
To refer a patient, please contact 202-660-6500. To discuss a case, call and ask for the physician on-call for hematologic oncology.