Demons-Meigs syndrome combines a benign ovarian tumor, ascites and pleural effusion. It is a rare pathology and its pathophysiology remains obscure [1]. The ovarian tumor frequently corresponds to a fibroma and a thecoma [2]. Fibroma accounts for 1% to 4% of ovarian tumors and is observed in 1% of cases in the context of Demons-Meigs syndrome [3]. The aim of our study is to report a case of Demons-Meigs syndrome, to determine its different characteristics and to make clinicians aware of the malignant predictive value of CA 125 in front of an ovarian tumor.

The patient was 42 years old and had no previous history. Several weeks before her admission, she presented with intense abdominal pain of sudden onset, triggered by prolonged sitting and calmed by non-steroidal anti-inflammatory drugs, prompting a medical consultation. On clinical examination, the abdomen was distended with signs of peritoneal effusion and right pleural effusion. Ultrasound revealed a well-circumscribed, irregularly contoured ovarian mass with an internal fluid component (Figure 1) and hypervascularization on Doppler. There was another right lateropelvic mass, tissue, hypoechoic, heterogeneous, measuring 119 × 89 mm, associated with a cluster of right iliac lymph nodes. These lesions were accompanied by a large, finely echogenic intraperitoneal fluid effusion and a medium-sized, nonpartitioned right pleural fluid effusion. The CA 125 level was elevated (293.9 U/ml). Exploratory laparotomy revealed two bilateral, firm, smooth ovarian tumors without vegetation or peritoneal lesions, which were removed (Figure 2). Macroscopically, one of the tumors was well circumscribed, lobulated with a smooth outer surface. It measured 20 × 17 × 8 cm and weighed 1400 g. The section slices were white, solid, firm, heterogeneous with cystic areas of 0.5 cm to 4 cm with mucoid content. The other tumor measured 19 × 11 × 5 cm, weighed 1090 g and had the same characteristics as the other tumor. Histologically, both tumors were a proliferation of fibroblastic spindle cells organized in short intersecting or storiform bundles, without cyto-nuclear atypia or excess mitoses (Figure 3 and Figure 4). In some places, tubular or tubulocordal structures were identified. The diagnosis retained was bilateral ovarian fibroma in the context of a Demons-Meigs syndrome. Regarding

the management, follow up and prognosis, the postoperative course was simple with disappearance of the pleural and peritoneal effusions at the 45th postoperative day.

Demons-Meigs syndrome is defined by the triad of benign ovarian tumor, ascites and pleural effusion [1]. The ovarian tumor frequently corresponds to a fibroma and a thecoma [2]. Fibroma accounts for 1% to 4% of ovarian tumors and is observed in 1% of cases in the context of Demons-Meigs syndrome [3].

Demons-Meigs syndrome is much more common in postmenopausal women, especially those around 50 years of age, and its peak incidence is in the seventh decade. It is extremely rare in women under 30 years of age [4] [5]. In the case of our patient, she was a 42-year-old woman near perimenopause.

In Demons-Meigs syndrome, ovarian tumors can be fibroma, thecoma, cystadenoma, or granulosa tumor, but the most frequently reported are fibroma and thecoma [2]. Fibroma is often unilateral but is sometimes bilateral. In our patient, it was a bilateral fibroma. Other tumors such as teratoma or struma ovarii may be associated with ascites and pleural effusion but in these cases, according to Peparini N and al, it would be a pseudo Demons-Meigs syndrome [6].

Several theories would explain the appearance of peritoneal and pleural effusions in Demons-Meigs syndrome [7]. First, mechanical theories, by vascular compression or cardiac decompensation were evoked. Then, the secretory theory, by mechanical irritation of the peritoneum due to a tumor (foreign body) or to the existence of a germinative secretory epithelium on the tumor was noted. Then, anaphylactic theories were added by histaminic toxicosis of the peritoneum by vasodilating histamine. Endocrine theories by endocrine dysregulation of the hyperestrogenic type could be due to the presence of a secreting tumor, either by minimal thecoma or by islands of thecal proliferation [7]. According to the experiments of Meigs [2], the persistence of the pleuroperitoneal duct would explain the pleural effusions. According to Liou JH [8], pleural effusions result from transudation of fluids through the transdiaphragmatic lymphatic trunks classically on the right side. Ascites would be attributed to fluid transudation related to direct pressure on the surrounding lymphatics and vessels, hormonal stimulation, or tumor torsion [8].

A significant elevation of the CA 125 level to a normal of less than 35 IU/l raises the suspicion of an ovarian malignancy. In our observation, the CA 125 level was 293.9 IU/l. During Demons-Meigs syndrome, it is classical to demonstrate an elevation of CA 125 which is an antigenic marker of the coelomic epithelium and its derivatives [9]. Several authors such as Plaisant N and al [9] or Santangelo M and al [1] have demonstrated that an elevated CA 125 level is not a good indicator of ovarian malignancy.

Treatment is based on surgical removal of the ovarian tumor which ensures that the effusions are dried up [10]. In our patient, she underwent bilateral oophorectomy. The postoperative course was simple with disappearance of the pleural and peritoneal effusions at the 45th postoperative day.

Demons-Meigs syndrome is a benign condition with a good prognosis with early management. Pleural effusion and ascites disappear permanently after tumor removal. The postoperative life expectancy of patients with this syndrome is equivalent to that of the general population after surgery [11].

Demons-Meigs syndrome is a rare entity. The concomitant elevation of the CA 125 level is not always an indicator of ovarian cancer. The curative treatment is surgical based on tumor removal ensuring the disappearance of peritoneal and pleural effusions.

We obtained the consent from the patient for the case study.

The authors declare no conflict of interest.

Elisabeth, R.H., Joëlle, R.V., Nalisoa, R.F., Lucas, R.Z., Ranaliarinosy, R.M. and Soa, R.N. (2023) Demons-Meigs Syndrome with a High CA 125 Level: A Case Report at Soavinandriana Center Hospital Antananarivo. Open Journal of Pathology, 13, 73-78. https://doi.org/10.4236/ojpathology.2023.132007