Conclusions
Liposarcomas commonly occur in the extremities, however, primary pleural
liposarcoma is extremely rare with very few reported
cases1. We could only find 34 reported cases of
pleural liposarcomas1-4.
The World Health Organization classifies liposarcoma into five types:
atypical, well-differentiated, dedifferentiated, myxoid, and
pleomorphic1. Of these, the dedifferentiated
liposarcomas have a significantly poor prognosis with rates of local
recurrence and metastasis of 41% and 17%, respectively, and 5-year
survival rate of only 28%. Conversely, the 5-year survival rate for
well-differentiated liposarcomas is 80% 5.
The curative treatment for
liposarcoma is surgical resection, with chemotherapy and/or
radiotherapy. Adjuvant chemotherapy is selectively applied because the
subtypes differ in chemosensitivity; it is not indicated in the
resistant subtypes of dedifferentiated liposarcomas. Radiation therapy
reportedly reduces the risk of local recurrence, especially in cases
with myxoid liposarcoma3.
Regarding surgical resection of the tumor at the cavoatrial junction,
Neves and Zincke classified venous tumor thrombus into four categories:
level I–renal vein thrombus, level II– infrahepatic IVC thrombus,
level III–retrohepatic IVC thrombus, and level IV–intraatrial IVC
thrombus. In the presented case, the cavoatrial tumor thrombus can be
classified as level IV. The standard surgical technique for level IV
tumor thrombus is resection with CPB. However, the use of CPB in
patients suffering from malignant diseases is controversial because CPB
decreases the immunity of patients and potentially causes the spread of
malignant cells to the whole body. Furthermore, CPB is associated with
the release of inflammatory mediators, coagulopathy, platelet
dysfunction, and increased bleeding. There have been contradictory
reports on the use of CPB in cancer patients6, 7.
Among 74 patients with metastatic cancer undergoing open-heart surgery
with and without CPB, no significant difference was reportedly observed
in cancer-specific mortality (patients with and without CPB: 26.7% and
24.1%, respectively, p=0.8)6. Conversely, another
report demonstrated among 43,347 patients undergoing isolated CABG
surgery, the adjusted relative risk of cancer-specific mortality caused
by CPB was 1.16 (95% CI: 0.92–1.46, p=0.20)7. The
lack of significant association between CPB and the progression of
malignant diseases allowed us to perform aggressive surgical resection
with CPB.
Similarly, there are no reports on HCA in cases with cavoatrial tumors,
particularly liposarcoma. It was reported that CPB with HCA to treat
level III or IV renal or adrenal tumors enabling complete tumor
resection did not increase operative risks and was relatively
safe8. The HCA proved useful in removing the
cavoatrial tumor completely and in viewing the inside of the IVC clearly
with endoscopy.
In conclusion, prompt complete resection of the cavoatrial metastatic
dedifferentiated liposarcoma associated with poor prognosis was
successfully performed using CPB with HCA, which resulted in
satisfactory mid-term survival without recurrence.
Acknowledgements: I acknowledge Jun Matsubayashi, a professor
at Tokyo Medical University, Department of Pathology, for assisting with
the pathological analysis of this case.