myelomonocytic leukemia (JMML) is a rare
type of blood cancer that occurs when bone marrow production of white blood
cells becomes severely disregulated. In children with JMML, the bone marrow –
the soft, spongy center of the bones responsible for creating blood cells – produces
immature white blood cells that grow too rapidly and keep reproducing even when
they run out of space. This crowds out healthy bone marrow cells and can lead
to symptoms such as infections, anemia, and bleeding. Currently, the only cure
for JMML is stem cell transplant.
Patients with JMML are treated at Dana-Farber/Boston
Children's through the Leukemia Treatment Program, one of the top programs worldwide for pediatric
leukemia. Our program has been instrumental in refining treatments for
childhood leukemia, which has resulted in improved cure rates and decreased
side effects. We also have one of the largest and most
experienced pediatric stem cell transplant programs in the U.S.
Our leukemia treatment team
includes internationally recognized pediatric hematologist/oncologists, hematopathologists
(who have specialized expertise in correctly diagnosing pediatric hematologic
malignancies like JMML), radiation oncologists, stem cell transplant physicians,
and pediatric oncology nurses.
is a blood cancer. It develops in the bone marrow – the soft, spongy center of
the long bones that produces the three major blood cells: white blood cells (to fight
infection); red blood cells (to carry oxygen); and platelets (to help blood clot and
About 90% of children diagnosed with JMML have been
found to have specific genetic mutations that can be identified by a special laboratory. These
mutations occur in a type of white blood cell known as a monocyte, which are a
part of the body’s immune system. Children with Neuroﬁbromatosis
type 1 and Noonan syndrome are more likely to develop JMML.
important to understand that there’s nothing you could have done or avoided
doing that would have prevented your child’s cancer from developing.
Because JMML is a cancer
of the blood-forming bone marrow, initial symptoms are often related to
abnormal bone marrow function. The bone marrow is responsible for storing and
producing about 95 percent of the body's blood cells, including the red blood
cells, white blood cells, and platelets.
While each child
may experience symptoms of JMML differently, some of the most common include:
It is important to
understand that the symptoms of JMML may resemble other blood disorders or
medical problems. These are common symptoms of the disease but do not include
all possible symptoms. Because many of these symptoms can also point to other
conditions, it’s important to have your child evaluated by a qualified medical
professional right away for an accurate diagnosis and prompt treatment.
The first step in treating your child is forming an accurate and complete diagnosis.
JMML is often suspected due to results from a routine blood test conducted for other reasons.
Your child’s physician may order a number of different tests including:
There may be other
diagnostic tests that your doctor will discuss with you depending on your
child's individual situation. After we complete all necessary tests, our
experts meet to review and discuss what they have learned about your child's
condition. Then, we will meet with you and your family to discuss the results
and outline the best possible treatment options.
JMML is not easily
treated, though several therapies offer hope for a successful outcome. A stem
cell transplant is the best option, though your child's team may consider other
medications and procedures as well.
treatment may include:
your child's stem cells are replaced with those of a healthy and compatible
donor, it is called allogeneic transplantation. The goal is for healthy stem
cells from another person (whose tissue must be the same, or almost the same,
as your child's) to restore your child's normal blood production.
children undergoing a stem cell transplant for JMML must receive high-dose
chemotherapy to make room in their bone marrow for the new stem cells. Called a
“conditioning regimen” this chemotherapy accomplishes several important things.
It suppress the body’s immune system to prevent rejection of the stem cells,
and it destroys cancer cells in the body. Like a blood transfusion, stem cells
are given to a child through an intravenous (IV) catheter. Children are awake
through this painless process. It generally takes two to four weeks for the
stem cells to multiply and make new blood cells. This is called engraftment. Side
effects, such as fever, chills, and shortness of breath, can accompany the
infusion of stem cells. More significant complications, including graft
rejection and graft-versus-host disease (a condition in which the donor’s
immune cells attack the patient’s body), can occur following the transplant.
groups of chemotherapy drugs work in different ways. Your child may receive
chemotherapy orally, as a pill to swallow; intramuscularly, as an injection
into the muscle or fat tissue; intravenously, as a direct injection into the
bloodstream or IV; or intrathecally, as a direct injection into the spinal
column through a needle.
chemotherapy can be quite effective in treating certain cancers, the drugs
cannot differentiate normal healthy cells from cancer cells. As a result, there
can be adverse side effects during treatment. Being able to anticipate these
side effects can help the care team, child, and family prepare (and, in some
cases, prevent) these complications from occurring, if at all possible.
Of course, your child's team of doctors
will help determine the best approach for your child's unique situation, based
on a number of factors including:
Scientists at Dana-Farber/Boston Children's are on the
front lines of research involving pediatric cancers and blood disorders,
Stem Cell Transplant Center is one of eight institutions nationwide investigating
the use of umbilical cord transplantation as a novel method for preventing
graft versus host disease, a serious complication that occurs when transplanted
cells do not recognize the tissues and organs of the recipient's body and react
hostilely. The result of this treatment approach, if it continues to be
successful, will be that the degree of match between donor and recipient need
not be close, increasing the pool of potential donors for each patient. This
could also eliminate the need for long-term drug therapy traditionally needed
to treat graft versus host disease.
Clinical trials, or
research studies evaluating new treatment approaches, are a major offering at
Dana-Farber/Boston Children’s. Clinical trials are very important for children
with hard-to-treat or relapsed conditions.
Clinical trials at Dana-Farber/Boston Children's are designed
to investigate new therapies for refractory or relapsed leukemia, novel
combinations of chemotherapy drugs, and promising new treatment
agents. Our researchers are conducting randomized clinical studies to
reduce treatment intensity to lessen side effects and to test more intense and
newer therapies to improve cure rates.
We connect patients with trials available through collaborative groups such as the Children's
Oncology Group (COG) and the Pediatric Oncology Experimental Therapeutics Investigators'
Consortium (POETIC). We are the New England
Phase I Center of the Children's Oncology Group. If your child has a hard-to-treat
cancer, he or she may be eligible for a number of experimental therapies
available through these groups or from one of our independent clinical
Oncology Group is a
consortium of cancer treatment centers across the United States, Canada, and
other countries that conduct studies of nearly every kind of pediatric cancer.
Our participation in this group gives children with cancer unparalleled access
to the newest clinical trials.
Despite advances in treatment, JMML remains difficult to
cure. Without treatment, the five-year survival rate is dismal (about 5%).
Stem cell transplantation has proven to be a successful treatment; however, the
relapse risk is significant—about 50 percent—following a transplant. If JMML
recurs after a stem cell transplant, a second transplant may be an option.
with any cancer, prognosis and long-term survival varies greatly. Prompt medical
attention and aggressive therapy are important for the best prognosis, and
continuous follow-up care is essential. New methods are continually being
discovered to improve treatment and decrease side effects of the treatment for
Some children who are treated for JMML and other pediatric cancers can experience
significant long-term problems as a result of their treatment. All kids who
have been treated for cancer require ongoing, specialized care.
Through the David B. Perini Jr. Quality of Life Clinic, our cancer
survivorship clinic, childhood cancer survivors receive a comprehensive follow-up evaluation from their cancer care team. In addition to meeting with your pediatric oncologists, your child may see one of our endocrinologists, cardiologists, neurologists, neuro-psychologists, or alternative/complementary therapy specialists. We also offer patient and family education, psychosocial assessment, genetic counseling, reproductive counseling, and opportunities to speak with other childhood cancer survivors.
Phone: 617-632-5508Online form: Request an appointment
Andrew Place, MD, PhD, offers basic information about pediatric leukemia – including what to look out for.
World class cancer care at the #1 children's hospital