spontaneous, transient regression of B lymphoblastic leukemia in an adult patient: a variant presentation of prodromal/pre-ALL

Case Details

Disease Location

Bone marrowithblood

Personal Characteristics

50 -year-old female history of hypertension, diabetes, and dyslipidemia, she was treated with regular medication she also reported an herbal supplement for weight control

Clinical Characteristics

2 months history of fatigue and detection of circulating blasts on peripheral blood smear blasts were variable in number on smears, reported as high as 20% but spontaneously decreased and became undetectable over the 2 week period preceding her transfer physical exam after transfer showed mildly pale sclera peripheral blood exam revealed pancytopenia with total wbc count of 11,000/ul, absolute neutrophil of 200/ul, hgb of 8.8g/dl, and platelet count of 64,000/ul bone marrow aspirate yielded a dry tap trephine biopsy demonstrated a variably cellular bone marrow (10-70%) with erythroid and megakaryocytic hyperplasia and interstitial small lymphocytosis fat cells had a diffuse fibrinoid appearance, suggestive of stromal damage mild fibrosis was present there were variably scattered and loose clusters of immature lymphoid cells with high nuclear/cytoplasmic ratios, irregular nuclear contours, finely granular chromatin and small nucleoli ihc studies revealed that these cells comprised approx. 10-20% of the marrow cellularity overall and expressed CD34, tdt and pax5, consistent with b-lymphoblasts b-lymphoblastic leukemia/lymphoma was diagnosed with the atypical histologic features 5 months after initial presentation, the patient returned, she was asymptomatic but lab studies revealed a wbc of 24,900/ul with 68% blasts and a platelet count of 47,000/ul marrow and trephine biopsy demonstrated replacement of normal marrow elements by 90% CD10+, 19+, 34+ lymphoblasts fish showed hyperdiploid with numerical abnormalities of chromosomes 10, 11, 17, and 21 diagnosis of pre-b-all was made and patient was administered bfm based chemo regimen

Remission Characteristics

A few days after marrow biopsy, peripheral blood counts partially recovered, she remained asymptomatic and declined therapy one months later, the patient was asymptomatic without any treatment, with complete normalization of the peripheral blood counts, no peripheral blasts were seen by morphologic or flow cytometrics repeat marrow aspirate smear and trephine biopsy demonstrated a normocellular marrow with unremarkable trilineage hematopoiesis and normalized fat spaces in the majority of the specimen occasional lymphoid aggregates composed of a mixture of small t- and b-cells were noted in non-paratrabecular locations there were persistent but decreased numbers of immature b-cells (10%) with the previous CD34, pax5, tdt positive phenotype scattered through the marrow, but most prominent in aggregates of small lymphocytes and focally increased eosinophils flow cytometrics showed immature b-cell population expressing moderate CD45, 19, 10 and 34 without CD20 or surface immunoglobulin after bfm chemo was inducted, patient achieved remission

Treatment & Mechanisms

Proposed Remission Mechanisms

Possibility of an immune response that my have temporarily prevented outgrowth of the neoplastic blast population (presence of increased t lymphocytes and eosinophils surrounding the b lymphoblast aggregates)

Clinical Treatment

Chemo (bfm based chemo regimen)

Non-Clinical Treatment

None reported