Leukemias, lymphomas & oncologic emergencies

◆Acute leukemias

• •ALL: kids, pancytopenia, hepatosplenomegaly, bone pain, mediastinal mass (T-cell) — treat with combination chemo + CNS prophylaxis
• •AML: adults, Auer rods, gum hypertrophy (M5), DIC (M3 = APL)
• •APL (M3): t(15;17), Auer rods bundles, DIC — start ATRA empirically (don't wait for genetics)
• •AML risk: prior chemo (alkylators), radiation, MDS, Down syndrome, benzene
• •Diagnosis: ≥20% blasts in marrow

◆Chronic leukemias & myeloproliferative

• •CLL: elderly, smudge cells, indolent, often asymptomatic — observation if early; treat with ibrutinib / venetoclax / chemoimmunotherapy when symptomatic
• •CLL complications: hypogammaglobulinemia (infections), AIHA, Richter transformation to DLBCL
• •CML: BCR-ABL t(9;22), massive splenomegaly, basophilia — imatinib (TKI); monitor BCR-ABL PCR
• •Hairy cell leukemia: middle-aged men, massive splenomegaly, pancytopenia, hairy cells with TRAP positivity — cladribine
• •Polycythemia vera: JAK2 V617F, pruritus after hot showers, erythromelalgia — phlebotomy + ASA
• •Essential thrombocythemia: platelets >450k, JAK2/CALR/MPL — ASA + hydroxyurea if high-risk
• •Myelofibrosis: tear drop cells, leukoerythroblastic blood, massive splenomegaly — ruxolitinib, allogeneic SCT in young fit

◆Lymphomas

• •Hodgkin: Reed-Sternberg cells (CD15+ CD30+), bimodal age, B symptoms, contiguous nodal spread, EBV-associated — ABVD chemo, highly curable
• •Hodgkin alcohol-induced node pain (rare but classic)
• •NHL: more common than HD, NON-contiguous spread, extranodal involvement common
• •DLBCL: most common NHL, aggressive but curable — R-CHOP
• •Follicular: indolent, t(14;18) BCL-2 — watchful waiting if asymptomatic; rituximab + chemo when symptomatic
• •Burkitt: c-MYC t(8;14), highest mitotic rate, starry sky — aggressive curative chemo, TLS prophylaxis essential
• •MALT lymphoma (stomach): H. pylori → triple therapy can be curative if low-grade

◆Plasma cell disorders

• •MGUS: M-spike < 3 g/dL, marrow <10% plasma cells, NO end-organ damage — observe, ~1%/yr to myeloma
• •Multiple myeloma: CRAB (Calcium ↑, Renal failure, Anemia, Bone lytic), M-spike, ≥10% clonal plasma cells
• •MM workup: SPEP, UPEP, serum free light chains, X-rays (NOT bone scan), bone marrow
• •Waldenström: IgM monoclonal gammopathy, hyperviscosity syndrome (headache, blurry vision, retinal vein engorgement)

◆Oncologic emergencies

• •Tumor lysis: high cell-turnover tumors post-chemo (Burkitt, ALL); ↑ K, ↑ PO4, ↓ Ca, AKI — IV fluids + rasburicase
• •Febrile neutropenia: ANC <500 + fever >38.3 once or >38.0 sustained → cultures + empiric pip-tazo/cefepime within 1 hour
• •Spinal cord compression: back pain + neurologic deficits + known malignancy → emergent MRI + IV dexamethasone + radiation/surgery
• •SVC syndrome: facial/upper extremity edema, JVD, dyspnea; lung cancer (small cell), lymphoma → CT, biopsy, radiation, stenting
• •Hypercalcemia of malignancy: PTH suppressed, PTHrP elevated → IV fluids + bisphosphonate (zoledronic acid) + calcitonin for acute
• •Hyperleukocytosis: WBC >100k in AML → leukapheresis + induction; risk of leukostasis (CNS, lung)

Translocations to know