Spontaneous remission of acute lymphoblastic leukemia: A series of nine cases and a review of literature

T-ALL presenting with i-TLP-like indolent clinical course with repeated spontaneous regressions

Rapidly progressing ALL, a potentially fatal disease, demands timely diagnosis and treatment. On the other hand, spontaneous remission/regression (SR) is reported in various cancers including aggressive tumors like ALL. Infection or trauma-mediated immune system activation is assumed to cause SR, with the duration in cases of ALL typically being short. Indolent T-lymphoblastic proliferation (i-TLP) exhibits the uniform proliferation of TdT-positive T-cells, despite being a non-neoplastic disease, underscoring the significance of distinguishing it from T-cell acute lymphoblastic leukemia (T-ALL). i-TLP is expected to gain wider recognition and further advancements in understanding its pathology. Here, we present the case of a 59-year-old woman with T-ALL characterized by cycles of progression and SR followed by a rapid blast proliferation. This is the first reported case of T-ALL with repeated SR for more than one year, making this case an extremely rare clinical presentation. This challenging case will enhance comprehension of T-cell tumor pathogenesis.

Immunophenotypic properties association of CLL and ALL patient cells by flow cytometry analysis

Chronic lymphocytic leukemia (CLL) and acute lymphoblastic leukemia (ALL) are blood cancers that affect lymphocytes and can be diagnosed by flow cytometry. Flow cytometry is a laboratory technique that analyzes cell properties, including cell surface markers such as cluster of differentiation 19 (CD19).

Objective

The main objective of this study was to explore the correlation of the number of CD19-positive cells with other CD antigens in patients with CLL and ALL.

Methods

After receiving ethical approval (Approval No. 5S/401), blood was collected from participants who had been diagnosed by a physician. Then the collected blood was prepared for flow cytometry analysis according to the protocol by staining with fluorescent antibodies.

Results

The results of the current study showed that sex and different age groups had no statistical influence on the number of CD19-positive cells in the patients evaluated. The generated models did not reveal an association with the number of CD19-positive cells in patients with CLL and ALL. In patients with CLL, the number of cells expressing CD5, CD20, CD23, and CD200 was significantly and positively related with the number of CD19-positive cells. In patients with ALL, the number of cells expressing CD79 and CD99 was significantly and positively correlated with the number of CD19-positive cells. This comparison study also found that in patients with CLL, the number of CD19-positive cells was significantly higher than the number of cells expressing CD20, CD23, and CD200. In patents with ALL, there was a significantly higher number of CD19-positive cells than CD34-positive and CD79-positive cells.

Conclusion

In patients with CLL, there was a strong positive correlation between the number of CD19-positive cells and the number of cells expressing CD5, CD20, CD23, and CD200. Additionally, in patients with ALL, there was a positive correlation of CD79 and CD99 with the number of CD19-positive cells.

Spontaneous Remission of Acute Lymphoblastic Leukemia Following Candida tropicalis Fungemia

Spontaneous remission (SR) in acute lymphoblastic leukemia (ALL) is a poorly understood phenomenon that has been sporadically reported in medical literature for over a century, and the molecular and immunologic mechanisms of remission pose interesting clinical questions. Furthermore, the often-transient nature of these remissions poses a challenge to physicians in formulating an approach to treatment. We report on a rare case of Candida tropicalis sepsis in a three-year-old female with high-risk ALL who received less than two months of treatment prior to sepsis and subsequent SR.

B-lymphoblastic leukemia with transient spontaneous remission in the setting of severe group A streptococcus infection

Spontaneous remission of B-lymphoblastic leukemia (B-ALL) in the setting of viral and bacterial infections has been reported. Here, we present a case of B-ALL that showed a complete remission in the setting of group A streptococcal bacteremia. The patient was an 11-year-old boy who presented with a sore throat, right ear pain, and rhinorrhea. Prior to the diagnosis of B-ALL, he was diagnosed with streptococcal pharyngitis and received a single dose of dexamethasone and azithromycin. One day later, he was found to be pancytopenic and an immunophenotypically abnormal B-lymphoblastic population was detected comprising 0.6% and 16.8% of the peripheral blood and bone marrow cells, respectively. Though a diagnosis of B-ALL was highly suspected, blast percentage was <20% and the bone marrow showed relatively unremarkable trilineage hematopoiesis. On close monitoring, the suspected neoplastic population became undetectable by day 17 and the patient's complete blood count (CBC) completely normalized by day 46. On day 82, a peripheral blood smear demonstrated circulating blasts. Flow cytometry of a bone marrow aspirate revealed B-lymphoblastic leukemia accounting for 94% nucleated cells, consistent with the diagnosis of B-lymphoblastic leukemia. This case is of interest as less than 20 examples of spontaneous remission of B-ALL have been reported in the literature. As the case reported here relapsed and previously reported spontaneously remitting cases have uniformly relapsed, cases of B-ALL with spontaneous remission should be followed very closely for recurrence.