Congratulations and Happy Match Day!!! Thank you to Dan Reiss, for presenting a case of a middle-aged woman with systemic symptoms and pancytopenia, who was diagnosed with new acute lymphoblastic leukemia. We discussed ALL as an entity and also discussed tumor lysis syndrome!
SamMy (Sam & Myung)
- ALL is a rare disease in adults. Prognosis in adult-onset ALL is poor, with long-term survival of only about 40% with treatment.
- A positive Philadelphia chromosome confers a poorer prognosis.
- Tumor lysis syndrome is an oncologic emergency and requires urgent treatment: hydration, hypouricemic agents (allopurinol, rasburicase), management of severe electrolyte abnormalities (hyperK tx, phos binders, calcium repletion), and possible dialysis
Acute Lymphoblastic Leukemia
- We all recall from our med school years, that ALL is the most common form of cancer in children (~30% of all childhood malignancies).
- ALL in adults is a rare disease. However, there is a bimodal peak in incidence of ALL, so late-onset ALL can occur.
- In general, prognosis in poorer in ALL of adults compared to that in children. Long-term survival of older adults with ALL who are intensively treated is only 40%.
- ALL can be subdivided into B cell ALL vs T cell ALL
- Prognostic Factors
- Certain cytogenetic findings are associated with poor prognosis– Philadelphia chromosome positivity, t(4;11), complex abnormalities (more than 5 chromosomal changes)
- B-cell disease is associated with higher treatment failure rates
- Induction chemotherapy à consolidation à maintenance
- CD20/CD 22 antibodies as adjuncts to chemotherapy in B-cell ALL are being tested in RCTs.
- Tyrosine kinase inhibitors for Philadelphia + ALL
- Bone Marrow Transplantation
Tumor Lysis Syndrome (Blast from the Past)
Tumor lysis is an oncologic emergency caused by massive tumor cell lysis and release of potassium, phosphate, and uric acid. Uric acid or calcium phosphate crystal deposition can cause acute kidney injury.
2 or more of these values (or 25% change from baseline values) are necessary for “laboratory TLS”:
- Uric acid >8 mg/dL
- Potassium >6 mEq/L
- Phosphorus >4.5 mg/dL
- Calcium <7 mg/dL
Risk factors include high tumor cell proliferation rate, large tumor burden, kidney disease, dehydration, and chemosensitive tumors. TLS occurs much more frequently in hematologic malignancy compared to solid tumors.
TLS typically occurs after chemotherapy (usually within a week), and more cases are being seen with targeted therapies.
Prevention and treatment are determined by risk stratification but can include hydration, hypouricemic agents (allopurinol, rasburicase), management of severe electrolyte abnormalities (hyperK tx, phos binders, calcium repletion), and possible dialysis
“Clinical TLS” = Laboratory TLS + AKI, cardiac arrhythmia, or seizure.