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.
References
1. Arya LS, Thavaraj V, Kulkarni KP. Oncological
emergencies. In: Chaudhary P, Bagga A, Chugh K, Ramji R, Gupta P,
editors. Principles of Pediatric and Neonatal Emergencies: 3rd ed. New
Delhi: Indian Pediatr. (In press)
2. Arya LS, Narain S, Tomar S, Thavaraj V, Dawar R,
Bhargawa M. Superior vena cava syndrome. Indian J Pediatr. 2002;69:293-7.
3. Kulkarni KP, Marwaha RK, Trehan A, Bansal D.
Survival outcome in childhood ALL: experience from a tertiary care centre
in North India. Pediatr Blood Cancer. 2009;53:168-73.
4. Ingram L, Rivera GK, Shapiro DN. Superior vena cava
syndrome associated with childhood malignancy: analysis of 24 cases. Med
Pediatr Oncol. 1990;18:476-81.
5. Hon KL, Leung A, Chik KW, Chu CW, Cheung KL, Fok TF.
Critical airway obstruction, superior vena cava syndrome, and spontaneous
cardiac arrest in a child with acute leukemia. Pediatr Emerg Care.
2005;21:844-6.