Unexpected Huge Prevalence of Intracardiac Extension of Wilms Tumor—A Single Center Experience from a Ugandan Hospital

Abstract

Wilms tumor (WT) is the most common primary renal malignancy in young children. WT vascular extension to the inferior vena cava (IVC) occurs in 4–10% of cases and can reach the right atrium (RA) in 1%. Data on WT clinical presentation and outcome in developing countries are limited. The aim of the present study is to describe the prevalence of intracardiac extension in a consecutive population of WT patients observed in a large non-profit Ugandan hospital. A total of 16 patients with a histological diagnosis of 29 WT were screened in a 6-month period. Patient n°2, a 3 y/o child, presented with a 3-week history of abdominal distension, difficulty in breathing, and swelling of the lower limbs. A cardiovascular system exam showed rhythmic heart sounds, a heart rate of 110 beats per minute, and a pansystolic murmur on the tricuspid area; the abdomen was grossly distended with a palpable mass in the right flank, hepatomegaly, and splenomegaly. An abdomen ultrasound showed an intra-abdominal tumor, involving the right kidney and the liver and extended to the IVC. An ultrasound guided biopsy showed a picture consistent with WT. Cardiac echo showed a huge, mobile, cardiac mass attached to the right side of the interatrial septum, involving the tricuspid valve annulus, causing a “functional” tricuspid stenosis. The patient died of cardiogenic shock 7 days after admission. Patient n°3, a 3 y/o child, presented with analogue symptoms and the same diagnosis. The cardiac echo showed a round mass in the RA. Thirteen more patients were screened with cardiac echo, showing a normal heart picture. In our limited series, we found WT cardiac extension in three patients over 16 (19%). Cardiac echo performed routinely can lead to a better staging, prognostic, and therapeutic assessment. In our setting, the intra-cardiac extension could be more frequent than previously reported and might have prognostic implications.

Left Atrial Metastasis of Wilms Tumour in Abeokuta, Nigeria: A Case Report

“…Screening is therefore important for all categories of patients to limit disease-related morbidities and optimize care [19] . Our literature search revealed that only a few cases of intracardiac extension of WT have been reported in sub-Saharan Africa [9] , especially on the left side of the heart [11] . While the vena-caval extension of WT into the right atrium is a well-documented phenomenon, left atrial involvement is extremely rare [11] .…”

“…Management of advanced WT is multi-disciplinary and multi-modal [10,17] . Neoadjuvant chemotherapy has been proven to reduce the size of the atrioventricular tumour, with complete regression of the intra-cardiac mass in some reports [9,10,[17][18][19] . Surgical management of intra-cardiac tumours is formidable and technically challenging, especially in LMICs [8][9][10]18] .…”

“…Evidence of metastasis has been reported outside the abdominopelvic region in about 12% of WT cases, with the mode of spread being by direct extension, lymphatic or haematogenous spread [7] the lungs are the primary site for metastasis in more than 80%, with less frequent metastases to the liver, bones, and brain [7] and rarely the heart [8] . Intra-cardiac metastasis of WT, though rare, has been documented in literature [8,9] . In a case series by Mapelli et al [9] , among 16 histologically confirmed WT cases, the prevalence of intra-cardiac extension was as high as 19%.…”

“…Intra-cardiac metastasis of WT, though rare, has been documented in literature [8,9] . In a case series by Mapelli et al [9] , among 16 histologically confirmed WT cases, the prevalence of intra-cardiac extension was as high as 19%. The tumour has been reported to spread to the inferior vena cava (IVC) in about 4-10% of cases, the right atrium in approximately 1%, 9,10, and very rarely to the left atrium [11] .…”

“…Patients with metastasis to the heart may be asymptomatic and identified during routine echocardiography. Others may present with abnormal cardiac findings such as dynamic tricuspid valve obstruction, or cardiogenic shock [5,6,8,9] . Wilms tumour is highly chemo-sensitive and curable, with 5-year overall survival (OS) and event-free survival (EFS) in developed countries approaching 90% with the current multi-modal treatment strategies.…”