A new surgical approach for nephroblastoma with a tumor thrombus
in the lower vena cava reaching the right atrium
Dear editor:
Malignant renal tumors account for 6% of all pediatric tumors, with
Wilms’ tumor (WT) being the most
prevalent1. Tumor emboli (TE) invade the
inferior vena cava (IVC) and
reach the right atrium in 5–10% of patients2. IVC
thrombectomyis is a complex procedure with a surgical complication rate
of 16.2–20.3%3 . Preoperative chemotherapy can
reduce tumor and thrombi volumes and improve patient survival.
Preoperative chemotherapy and delayed surgery are usually recommended to
reduce the size/extent of the TE and minimize surgical
complications4; nevertheless, TE adhesion to the
vascular wall (VW) is common and can result in fracturing of thrombi and
difficulty in removing emboli. The right atrium and IVC are opened and
TE are removed during cardiopulmonary bypass (CPB) and deep hypothermic
circulation arrest (DHCA) 5, 6. Invasion of the VW by
tumor thrombi may necessitate partial resection and repair. However,
this can increase intraoperative blood loss and transfusion rate and
carries a risk of disseminating intravascular coagulation and tumor
spread7. Small movable thrombi can be removed through
a buttonhole in the vessel, while larger thrombi may require more
extensive cavotomies, and adherent thrombi require partial
resection/reconstruction. However, the use of bioartificial blood
vessels or vascular patch materials carries a risk of thrombosis and
infection, and autologous vascular transplantation can cause
damage8 . As children grow, they require patch
materials with growth potential.
Falciform ligament (FL) is useful
for repairing the IVC during liver surgery. FL is easy to obtain and
adjust in size/shape. Compared to polyester/polytetrafluoroethylene,
vascular repair with FL is associated with a lower risk of thrombosis
and graft infection, and no risk of rejection or need for therapeutic
anticoagulation9, 10.
There are currently no reports on
tumor thrombus (TT) removal from
the IVC and right atrium without CPB and CHCA. Here, we report a novel
pediatric surgical technique wherein the right atrium was incised before
thrombectomy was performed without CPB and DHCA, and FL was used to
repair the IVC.
A 5-year-old girl was
diagnosed with WT with an IVC TT.
Tumor size was reduced after four cycles of the CCCG-WT-2016
chemotherapy regimen (from 11.3×8.5×12.2 cm to 3.8×5.0×6.2 cm). The
patient then underwent right radical nephrectomy and thrombectomy
without CPB and DHAC. An intraoperative ultrasound showed that the TT
had invaded the IVC and entered the pericardium over the second hepatic
hilum, moving 1.5 cm into the right atrium. (Fig. 1). The left renal
vein and IVC were cut longitudinally, and the thrombi in the left renal
vein, IVC, and right atrium were removed. The TT adhered to the blood
vessel wall and into the surrounding branches showing drill-like growth,
which was fully removed. The longest vascular occlusion time was 33 min.
Continuous sutures with 4-0 silk were used to repair the blood vessels.
Complete resection of the right renal tumor, perirenal fat sac, and
ureter was achieved. Stenosis of the IVC blocked blood flow, and the
liver was enlarged. Therefore, blood flow could not be returned to the
abdominal cavity, and the patient’s blood pressure decreased to 40/30
mmHg. The diaphragm was reopened and the suture was removed from the
right anterior stenosis of the IVC. The right vessel wall of the IVC was
found to have been eroded by the tumor and was not amenable to suturing.
A 3-cm long and 1-cm wide section of the FL of the liver was resected
and used to suture the forearm of the IVC continuously with 5-0 silk to
repair the VW. Upon release of the clamp the IVC filled, the blood
supply was restored, and the swelling/congestion of the liver was
relieved. The patient made a full recovery and was discharged 10 days
later without complications. Over the next 3 years of follow-up, the
patient developed normally into a healthy school-age child.
Blocking the right atrium below the level of the coronary artery, below
the sinoatrial node, can thus be used to open the right atrium and
remove TTs without CPB or DHCA, which offers a viable new surgical
protocol. Fibrosis of blood vessels and TTs caused by multiple courses
of chemotherapy in the IVC, and adhesion of these TTs, can lead to
thickening and brittleness of the blood vessel walls and stenosis of the
lumen. This can necessitate TT removal and suturing of the VW after a
longitudinal split, which can in turn lead to further stenosis of the
lumen, resulting in reflux disturbance of the hepatic venous system and
systemic circulatory system below the second porta hepatis. The body
adapts slowly and establishes systemic collateral circulation in the
process of tumor growth; therefore, the enlargement and reconstruction
of the vascular segment of the IVC at the diaphragm level can solve the
problem of blood return obstruction. In contrast to more rigid
materials, the FL is a strong
double-sided peritoneum with excellent tension resistance and smooth
surfaces suitable for facing blood vessels. It is easy to obtain, its
removal has no deleterious effects, and it is, therefore, an ideal
material for repairing the IVC. This case demonstrates that this
surgical technique is safe and effective.