Etiology, complications and management protocols for superior vena cava obstruction (SVCO) in children are well recognized [1]. However, there is paucity of literature addressing SVCO at presentation in childhood acute lymphoblastic leukemia (ALL), its association with risk factors, prognostic impact and outcome [2]. Herein, we describe our management experience of 24 (3.14%) children with ALL presenting with SVCO at diagnosis out of 762 patients managed at our center from January 1990 to December 2005 and followed until January 2009 [3]. Therapy protocols were modified United Kingdom ALL (UKALL) X and XI.

Dyspnea, orthopnea, stridor, facial puffiness with plethora and venous engorgement along with constitutional symptoms of fever, pallor, fatigue and bleeding were the most common presenting features. The diagnosis of ALL was confirmed in all patients by bone marrow examination. The extent of disease was delineated by computed tomography in patients presenting after 2000 with cautious use of procedural sedation where needed.

Four had frank superior mediastinal syndrome (SVCO with significant and manifest tracheal compression with respiratory distress or failure) while 1 presented with raised intracranial pressure (ICP). Emergency radiotherapy was not used in any of these patients. SVCO was managed as per standard guidelines [1].

On comparison with other ALL children and those in Continuous complete remission, children presenting with SVCO at diagnosis had significantly higher incidence of hepatomegaly, splenomegaly, lymphadenopathy, bulky disease, mediastinal adenopathy, overt testicular disease and high total leukocyte count at presentation. Ten (47.1%) had hyperleukocytosis. In contrast, age, gender, symptom diagnosis interval, hemoglobin and platelet counts at diagnosis were similar in the 3 groups.

Seventeen patients opted for therapy while 7 cited socioeconomic reasons for therapy refusal. 4 (2 combined, 1 bone marrow and 1 central nervous system) relapsed, 4 died (within 1 day to 3 weeks from diagnosis), 4 were lost to follow up or defaulted therapy. There were 5 (29.4%) survivors at median follow up periods of 41 months (range: 29-84 months). The survival outcome was significantly inferior as compared to the entire cohort (n=762) by univariate log-rank analysis (P=0.045)(3). However, SVCO at presentation did not have independent prognostic impact (P=0.12) in multivariate Cox-regression analysis.

To the best of our knowledge, this is the largest study till date describing SVCO at presentation in ALL [2,4]. We observed a very high incidence of SVCO at presentation (in contrast to 0.27% reported in a study from America) and identified a range of associated adverse and high-risk factors [4]. Additionally, SVCO had an inferior outcome in contrast to 67% and 50% survival reported earlier [2,4]. Further large scale and collaborative studies to confirm these observations and assessing the molecular and cytogenetic characteristics of this unique presentation are necessary. Reinforcement and implementation of standard management guidelines, educational initiatives, better supportive care and management of anticipated complications (respiratory compromise, thrombosis, tumor lysis syndrome, ICP) should improve the outcome [5].

Although uncommon, oncologists and pediatricians are likely to encounter a child with ALL presenting as SVCO and need to be aware of this potentially treatable medical emergency.