Abstract
Background : Primary pericardial malignant mesothelioma is a
highly malignant and rare tumor. We present a case of primary
pericardial malignant mesothelioma in an adult male patient and review
the relevant literature to extend the understanding of the disease.
Methods: The patient underwent pericardial decortication
through the cardiopulmonary bypass, which effectively relieved the
clinical symptoms caused by the tumor blockage.
Results: Postoperative pathological diagnosis and
immunohistochemistry resulted in primary pericardial malignant
mesothelioma. The patient recovered after surgery and was followed up
regularly after discharge.
Conclusions: Primary pericardial malignant mesothelioma lacks
characteristic clinical and imaging manifestations, invariably resulting
in misdiagnosis. Pathological results combined with immunohistochemistry
are the gold standard for diagnosis. Surgery is the mainstay of
treatment, but the prognosis is extremely poor.
Keywords : Primary pericardial malignant mesothelioma; cardiac
surgery; pathological diagnosis; immunohistochemistry; case report
Introduction
Primary malignant pericardial mesothelioma (PPM) is a malignant heart
tumor originating in the serous pericardium and is highly invasive1,2. Through the collection of clinical data from a
patient with PPM and literature review, the clinical manifestations,
diagnostic methods, treatment and prognosis, pathological results and
immunohistochemical characteristics of PPM are further discussed to
expand the understanding of the disease and improve its diagnosis and
treatment.
Case report
A 30-year-old man was hospitalized for dyspnea 1 year ago and initially
diagnosed with tuberculous pericarditis. The patient regularly underwent
anti-tuberculosis and other related treatments for 6 months and was
discharged after symptoms were relieved. Over 50 days, the patient
developed cough, sputum production, pronounced dyspnea without obvious
causes, and concomitant alcoholic cirrhosis. The patient underwent
enhanced computed tomography (CT), which revealed diffuse thickening of
the pericardium and nodular changes (Fig. 1). Cardiovascular magnetic
resonance (CMR; Fig. 2a,b) confirmed that the pericardium was diffusely
thickened and abnormally strengthened, limiting cardiac contraction and
extending.the mass along the left ventricular wall with possible
invasion of the left heart, and tumor-like lesions were not excluded.
Positron emission computed tomography suggested uneven thickening of the
pericardium and increased metabolism, with infectious lesions being
considered first. The patient received anti-tuberculosis therapy while
reducing the burden on the heart and nourishing the myocardium by
diuresis. On day 22 of the preoperative preparation, the patient
suddenly suffered respiratory failure and was placed on a ventilator for
endotracheal intubation. After heart failure and oxygenation indicators
improved, pericardial decortication was performed. The patient was
placed in a flat recumbent position and monitored intraesophageally by
esophageal ultrasound. An anterior median incision of the sternum was
made to enter the chest cavity, and examination revealed that the
pericardium was thickened and extensively adhered, and the heartbeat was
weak.Opening the pericardium longitudinally from the anterior wall of
the right ventricle, the pericardium is markedly thickened (about 1.0 cm
at the thickest point) and contractures without significant
calcification.The visceral pericardium was closely adhered, and the
thickened pericardium was carefully separated by gradually peeling up to
the root of the aortic, down to the diaphragm, to the left side to the
anterior diaphragm nerve, and to the right side to the atrium in the
order of the outflowing tract first and then into the tract. The
thickened visceral pericardial tissue at the apex of the heart was
tightly adhered to the heart and was released where it could not be
peeled off. The area of excision and release of the pericardium was
approximately 15 cm × 10 cm. Cardiac beats were seen to be significantly
strengthened, and central venous pressure was slightly lower than before
surgery. The surgery was effective, and the patient was treated in
intensive care after surgery and underwent three rounds of artificial
liver therapy for liver failure and ventilator-assisted therapy for 8
days. The patient was not treated again for tuberculosis, and did not
receive tumor-related treatment owing to liver failure and poor systemic
condition. He was discharged from the hospital 44 days after surgery.
Postoperative pathological results revealed pericardial fibrous tissue
hyperplasia and endothelial cell hyperplasia in the shape of a cord
(Fig. 3a,b). Mesothelial cell atypia was not pronounced. Hyperplastic
mesothelial cell cords were arranged in some areas, and mucoid
degeneration could be observed around them. In the immunohistochemical
results, adenoid structural cells were CK(+), EMA (partial +), CK5/6
(+), HBME-1 (+), calretinin (+), WT1 (+), D2-40 (+), CEA(−), TTF-1(−),
CK7(+), CK20(-), CDX-2(−), CD31(−), CD34(−), FLi1 (+), p53 (partial+),
Vim (+). ), p16(−), GLUT1 (partial +), desmin(−), Ki-67 (approximately
20% +) (Fig. 4a,b,c,d). Histological images combined with marker
results resulted in a diagnosis of pericardial-reactive mesothelial cell
hyperplasia and pericardial malignant mesothelioma (epithelial-like
type).