Isolated myocardial relapse of Philadelphia-positive acute lymphoblastic leukaemia causing myocarditis: a case report

Abstract

BackgroundRelapse of acute lymphoblastic leukaemia (ALL) causes significant morbidity. Extramedullary relapse is seldom isolated to one site and almost always coexists with extensive marrow disease. Leukaemic infiltration of the myocardium is a well described entity, evident in up to 44% of patients at post-mortem examination; however, ante-mortem diagnosis remains difficult and rare. As a result, myocardial involvement in the absence of any other foci of relapse has only seldom been reported.Case summaryHere, we present an unusual case of isolated gross intracardiac relapse of ALL in a patient presenting with chest pain and fevers. Both cardiac magnetic resonance imaging and endomyocardial biopsy were utilized in the diagnosis and identified leukaemic infiltrate in the absence of peripheral lymphoblasts.DiscussionDespite evidence supporting a positive correlation between peripheral lymphocyte count and myocardial infiltration, our case highlights the rare and hypothesis-driving occurrence of myocardial infiltration with a complete absence of a peripheral lymphoblastosis. The report highlights the utility of modern histopathological and imaging modalities in the diagnosis of isolated myocardial relapse of ALL and provides insight into the aetiologies driving this process.

Other (Non-CNS/Testicular) Extramedullary Localizations of Childhood Relapsed Acute Lymphoblastic Leukemia and Lymphoblastic Lymphoma—A Report from the ALL-REZ Study Group

“…In contrast, ALL relapses in extramedullary compartments other than CNS or testis are poorly characterized and not addressed with specific treatment recommendations in current treatment protocols. Due to the relative rarity of these so-called other extramedullary relapses (OEMRs) and the large heterogeneity of organs involved, primarily case reports on single-center experience with unusual extramedullary localizations have been published so far [4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20][21][22][23]. Gunes and colleagues described other extramedullary relapses in 6 out of 51 adult and adolescent ALL patients following HSCT.…”