Introduction

Why is leukemia important to pediatric surgeons?

Unlike solid tumors, the outcome of pediatric acute leukemia isn’t predicated on requisite surgical interventions. However, the child with leukemia frequently requires the attention of a pediatric surgeon for placement and maintenance of central venous access, the diagnosis and control of infection and evaluation of unexpected abdominal complications [1][2][3][4][5]. Knowledge of normal hematopoietic development, the specific type of leukemia and the consequences of therapeutic treatments are critical for the pediatric surgeon contemplating an elective or emergent invasive procedure.

Which aspects of leukemia are the most challenging for the pediatric surgeon?

Thrombocytopenia, neutropenia, chemotherapy induced immune suppression, anemia and equivocal physical findings can obscure a diagnosis and increase the risk for surgical interventions in the pediatric leukemia patient [1][6]. Minor and emergent surgical interventions alike may be compromised.

Unfortunately, little current data exists to guide surgical management in the leukemic child. Guidelines suggesting platelet levels of 20-, 50- and 100,000 are empirically accepted for common invasive procedures (e.g. bone marrow biopsy, lumbar puncture). While a platelet count greater 50,000/mm³ is often recommended for surgical procedures, no formal studies exist to support a preoperative platelet transfusion "trigger" for a leukemic child [6]. One would typically target a platelet count of at least 50,000/mm³ and continue to transfuse for signs of excessive bleeding.

Infections due to neutropenia (i.e. absolute neutrophil count (ANC) less than 500 cells/mm³), particularly catheter related infections, are also a common surgical risk for the leukemic child. The risk of catheter infection has been shown to be influenced by the severity of neutropenia and failure to give timely and appropriate perioperative antibiotics. Failure to diagnosis and eliminate septic foci, required prior to administration of immunosuppressive chemotherapy, may be associated with significant morbidity and mortality. Successful surgical management of these children often requires coordination of surgeons, oncologists and infectious disease physicians.

The chronic anemia of leukemia creates perioperative surgical risk and has implications for wound healing. While a hemaglobin of 8 g/dL is often well tolerated in an otherwise stable child with leukemia, significant respiratory and cardiac compromise may be associated with this degree of anemia in the surgical leukemic patient [7]. However, no specific hemaglobin concentration trigger exists for perioperative blood transfusion. Instead, transfusion is often in response to the clinical symptoms of acute or chronic loss (e.g. pulmonary dysfunction, cardiomyopathy and centrsl nervous system compromise). Further complicating transfusion therapy is the need for leukodepleted, irradiated, cytomegalovirus (CMV) negative blood products to reduce the risk of transfusion associated graft versus host disease, CMV transmission and febrile transfusion reaction.

Physical assessment, particularly abdominal examination findings, can be unreliable and misleading in the leukemic patient. Physical findings suggestive of acute abdomen, such as diffuse abdominal pain, distension, nausea and emesis are occasionally observed on initial presentation or in response to chemotherapy or stem cell transplantation in the leukemic child [8]. The localized peritonitis physical findings typical of acute appendicitis may actually be neutropenic colitis, a drug induced pancreatitis or, in fact, acute appendicitis. Furthermore, the common use of systemic steroids in the treatment of acute lymphocytic leukemia may mask serious surgical issues, delay intervention and complicate wound healing [9].

Content in this topic is referenced in SCORE Lymphoma/Leukemia overview