Hematologic and oncologic emergencies Doing the most good in the least time Malcolm L. Brigden, MD PREVIEW Several urgent problems in oncology and hematology may require that pri- mary care physicians start therapy wi thout waiting for subspecialist inter- vention. Most of these pr oblems are related to chemotherapy , which often consists of multidrug immunosupp r essive regimens , or to the effects of the cancer itself , such as hypercalcemia from bone metastasis or spinal cord compression from tumor extension . In this article , Dr Brigden reviews 11 such emergencies and the most efficient steps to take to manage them. E merge nci es in hematology and onco logy may be conve- nie ntl y grouped into three major categories: metabo li c crises, compressions and obstructions, and sympto matic cytope nias. 1 • 3 Primary care ph ys icians are often involved, because such emer- gency situations may be the ini- tial prese nting fe ature of disease or a comp li cation of known can- cer. In any case, appropriate manageme nt depen ds on not o nl y a correct diagn os is but also prognostic information, with considerat ion given to the poss i- bility of cure, significa nt remis- sion, or improvement in quality of li fe. This article provid es a concise overview of initial man- ageme nt of common emergency situations in hematology a nd oncology. Metabolic crises Among the most often encoun- tered metabo li c emergenci es a re hyperuricemia, hypercalcemia, hyponatremia (th e syndrome of inappropriate antidiuretic hor- mone [SIADH]), a nd tumor- associated hypokalemia. Hyperuricemia Hyperuricemia-wi th renal uric acid deposition and possible renal failure-occurs mos t commonly with high-grade lymphoprolifera- tive disorde rs (eg, Burkitt's lym- pho ma, lymphoblastic lymphoma), often in association with treat- ment. t.2 Rare cases of spo ntaneous hyperuricemic nephropa thy have been reported in patie nts who have aggressive lymphoma or leuke mi a, especia ll y if underlying VOL 109 / NO 3 / MA RCH 2001 / POSTGRAD UATE MEDICINE I H EMATOLOGIC AND ONCOLOGI C EME RGENCIES renal function is compromised. 3 In addition, cases have been re- ported of uric acid nephropathy in patients with chro nic mye lo - proliferative disorders, multiple myeloma, and squamous cell ca r- cinoma of the head and neck. 2 • 3 Presentat ion and evaluation: Rarely, a patie nt with hyperurice- mia may present with signs of acute gout, but usually, signs indi- cate uremia ( eg, nausea, vomit- ing, leth argy, oliguria). Levels of uric acid, creatinin e, phosphate, calcium, electrolytes, a nd bl ood urea nitrogen shou ld be deter- mined. Studies using intravenous contras t material should be avoided because of the possibility of dehydration, which further ag- gravates renal dete rioration. Treatment: A nticipation and preve nt ion of hyperu ri cemia should be the primary goal sY Therefore, any patie nt pre se nt ing wi th a high-grade lymphop ro lif- erat ive disorder or low-grade ly m- phoproliferative disease with bulky adenopathy should be pre- treated with hy drat ion, urinary alkalization (with use of sodium bicarbonate a nd acetazolamide [Daza mide, Oiamox]), and ad- ministration of a llopurinol (Zy lo- con tinued 143