Use of octreotide for relief of gastro-intestinal (GI) symptoms in systemic mastocytosis

Abstract

e present the case of an 82-year-old Caucasian female who was evaluated by hematology oncology for further work up and management of her chronic but progressive anemia. She reported weight loss, poor appetite, fatigue, nausea, several episodes of non-bloody diarrhea and increased abdominal girth over the past 3 months. On admission, her hemoglobin was 8.9 gm/dL, platelets were 43 k/mcl, WBC was 5.49 K/mcl with absolute neutrophil count of 3.73 k/mcl and 0% peripheral blasts. Her metabolic panel was abnormal for elevated LDH (245 U/L) and alkaline phosphatase (207 U/L). Her liver function tests were normal except for albumin of 2.5 g/dl. Computed tomography (CT) of the abdomen/pelvis showed splenomegaly, ascites, and retroperitoneal lymphadenopathy, a concern for a lymphoproliferative or metastatic disease. A bone marrow biopsy and aspirate performed to determine the cause of her progressive anemia and thrombocytopenia revealed hypercellularity (90%) and increased blasts (35% on the touch preparation). The blasts had scant cytoplasm and fine chromatin (blue arrows in Figure 1). In addition, there were paratrabecular infiltrates of round to spindled mast cells (red arrow in Figure 1), which by immunohistochemistry were strongly positive for tryptase (shown in Figure 2), CD117, CD68 and CD25. The blasts were weakly positive for CD117 and strongly positive for myeloperoxidase, CD56, Bcl-2, and CD43 (not shown). The aspirate was severely hemodiluted, likely due to the reticulin fibrosis observed in the biopsy. Flow cytometry specimen was also hemodiluted (9% blasts) with the following myeloid immunophenotype: CD33 positive CD13 positive CD56 positive CD117 partially positive CD34 negative HLA-DR negative. Based on these findings the patient was diagnosed with AML and SM, a subset of systemic mastocytosis with associated clonal hematologic non-mast cell lineage disease (SM-AHNMD). The patient’s diarrhea responded briefly to antimotility agent loperamide, but while awaiting definitive treatment plan, her symptoms worsened rapidly and required admission for severe, profuse non-bloody diarrhea, dehydration and abdominal distension. Splenomegaly and ascites were noted on clinical exam. Labs continued to show anemia and thrombocytopenia. Initial test was positive for clostridium difficile (C. diff). This was successfully treated with metronidazole and then with oral vancomycin. Subsequent tests for C. diff, other infectious agents and transglutaminase IgA antibody were negative. However, the patient continued to have multiple episodes of diarrhea with little relief from antimotility agents. Diarrhea was deemed secondary to SM. Extensive work up for portal hypertension was non-diagnostic. She could not undergo colonoscopy and liver biopsy due to thrombocytopenia. As a consideration for treatment with imatinib she was tested for BCR/ABL and PDGFRA fusion genes which were negative. KIT mutation analysis could not be performed due to lack of tissue sample. After a lengthy discussion with the patient regarding various options of treatment, she chose palliative care and hospice. However, severe diarrhea limited her transition to hospice; she was then started on a trial of octreotide every 8 h for her diarrhea. She had a rapid response with dra-