Background: Acute myeloid leukemia (AML) is a clonal, malignant disease of hematopoietic tissues, which carries a poor prognosis and a median survival of 12 months. Definitive treatment includes chemotherapy and hematopoietic stem cell transplantation. Spontaneous remission in AML is possible but extremely rare, with 100 cases reported since the 1980s. Even rarer is an indolent course of de novo AML, with only eight patients reported in literature surviving beyond 12 months without treatment. To date, no case report of indolent AML has yet been published locally.

Objective: This paper reports the first documented case of acute myeloid leukemia following an indolent course who achieved spontaneous peripheral remission in the Philippines.

Case: A 34-year-old female presented initially with a three-month history of fever, pallor, dizziness and body malaise. Complete blood count showed pancytopenia and bone marrow aspirate with biopsy revealed acute myeloid leukemia. She required multiple transfusions and developed severe sepsis secondary to osteomyelitis. After treatment with blood transfusion and antibiotics, the patient’s blood counts improved and were maintained at almost normal levels for the next 16 months. Multiple repeat bone marrow biopsies still showed diffuse infiltration with acute myeloid leukemia. She remained asymptomatic, did not require further blood transfusions and did not undergo chemotherapy.

Conclusion: We report a rare case of an indolent acute myeloid leukemia in a young female patient who had spontaneous peripheral remission following a severe systemic infection. Despite abnormal bone marrow morphology and no chemotherapy, our patient has remained asymptomatic with normal blood counts 16 months since diagnosis of acute myeloid leukemia. To our knowledge, this is the first case report of indolent AML following spontaneous peripheral remission in the local setting.

Keywords: Indolent acute myeloid leukemia, spontaneous remission

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