Laparoscopic Resection of a Subserosal Leiomyoma Presenting as Pseudo–Meigs' Syndrome

Introduction

The clinical triad presentation of a benign ovarian tumor (fibroma, thecoma, granulosa-cell tumor), ascites, and hydrothorax that resolves after removal of the tumor indicates Meigs' syndrome. ¹ A similar presentation of ascites and hydrothorax coexisting with other benign cysts or teratomas of the ovary or leiomyomas of the uterus, are referred to as pseudo–Meigs' syndrome. ² Although it might seem that uterine leiomyomas are the commonest benign tumors of the uterus, these tumors are rarely accompanied by ascites and hydrothorax, ³ and are even more rare when associated with elevated cancer antigen (CA)–125. ⁴ This article presents a rare case of a subserosal leiomyoma presenting as pseudo–Meigs' syndrome. To the best of the current authors' knowledge, this is the first case of a subserosal leiomyoma with pseudo-Meigs that was resected laparoscopically in contrast to other case reports whereby laparotomy was the standard surgical approach.^5–14

Case

In May of 2008, a 38-year-old woman presented after requesting, at her own risk, discharge from another hospital. She was diagnosed with a large, solid ovarian tumor with ascites, a diagnosis that was supported further by computed tomography (CT) scan of the mass. Given that an advanced ovarian malignancy was suspected, an exploratory laparotomy was suggested, which she refused. She had been well previously with no surgical or medical conditions/history aside from 3 abortions. She did not have any family history of breast or gynecologic malignancies; however she stated that her mother had an unknown benign brain tumor and her sister had a uterine leiomyoma.

A physical examination was conducted, and no masses were palpable in this patient's abdomen. However, ultrasonography (USG) showed a solid 8 × 9.8–cm mass in the left adnexae and a 3.1 × 1.5–cm mass in the right adnexae, with a normal-sized anteverted uterus (7.64 × 5.3 × 4.05 cm), and a normal endometrial lining (Fig. 1A); however, there was ascites. These USG findings suggested the possibility of a left, solid ovarian tumor with ascites. A CT scan of her pelvis showed a large heterogeneous mass with massive ascites. The uterus and bilateral ovaries appeared to be normal (Fig. 1B). This patient's chest radiograph result was normal. Routine preoperative laboratory test (full blood count, biochemistries, A–B–O blood typing, urine analyses and liver-function tests) results were all within normal range. Her carcinogenic embroyologic antigen (CEA) marker was normal (1.26 ng/mL); however, her cancer antigen (CA)–125 was elevated at 706.5 U/mL (normal: <35U/mL).

OPEN IN VIEWER

FIG. 1.

(A) Ultrasonography scan of the pelvis showing the pelvic mass adjacent to the left side of the uterine fundus with ascites. (B) Computed tomography scan of the pelvis showing a large heterogeneous mass with massive ascites. The uterus and bilateral ovaries appear normal. UT, uterus; CX, cervix.

With a suggested diagnosis of a benign ovarian tumor, laparoscopic surgery was arranged (planned with laparotomy conversion if a frozen-section biopsy proved malignancy). During the laparoscopic examination, normal appearances of the liver and subdiaphragmatic surfaces were noted with no evidence of peritoneal or pelvic spread of disease. However, clear-colored ascites of ∼500 mL was also noted. The bilateral adnexa and ovaries were of normal size and contours. A mass highly suggestive of a subserosal myoma, measuring 10 cm was noted (Fig. 2A); it was covered with omentum and adhered to the anterior abdominal wall (Fig. 2B). Frozen-section biopsies of this mass revealed that it was a leiomyoma. Histopathologic examination of the removed specimen confirmed the diagnosis of a leiomyoma, with sections showing myomatous nodules composed of interlacing bundles of smooth-muscle fibers.

OPEN IN VIEWER

FIG. 2.

(A) Laparoscopic view of the actual mass, seen as a subserosal leiomyoma originating from the fundus of the uterus, and normal bilateral ovaries. (B) Laparoscopic view of the subserosal leiomyoma resected away from the fundus of the uterus. Dilated engorged vessels were seen on the leiomyoma as well as adhesions to the anterior abdominal wall.

Institutional review board approval was not required for case reports based on the authors' institutional regulations.

Results

This patient recovered well from the procedure and was discharged on postoperative day 3. Her recovery was uneventful, and, upon subsequent outpatient visits her CA-125 levels declined until they normalized. There has been no recurrence of ascites, and she has remained symptom-free.

Discussion

This case was highlighted for its initially misleading clinical presentation and its subsequent laparoscopic surgical intervention. The subserosal myoma in this case was initially misdiagnosed as a solid ovarian tumor. Findings of a pelvic mass associated with ascites often always lead to conclusion that a patient has a gynecologic malignancy. In the current case, the large uterine leiomyoma was in close proximity to the left ovary and, on the CT scan, appeared to lack any relation to the uterus. This might have given rise to a difficult or confusing radiologic diagnosis; hence an ovarian tumor was presumed. This was compounded furthermore by the findings of ascites and elevated serum CA-125.

Usually, clinical, sonographic, CT, and magnetic resonance imaging findings of leiomyomas are typical and the diagnosis is simple. However, they can be heterogeneous in appearance, being hypo/iso/hyperdense or mixed in density on contrast-enhanced CT scans, especially if there are elements of degeneration, hemorrhage, necrosis or unusual growth patterns. ¹⁵ Nevertheless, for its simple utility and noninvasiveness, USG is the preferred diagnostic tool of gynecologists for detecting and evaluating pelvic lesions. Conventionally, the acceptable common practice here would be to perform a laparotomy via a vertical abdominal incision to explore the peritoneal cavity and obtain biopsy material for histopathologic examination. Nevertheless, laparotomy, if only for biopsy could induce many setbacks, particularly in elderly patients with medical conditions or in obese patients who present with malignant ascites of unknown etiology. ¹⁶ This consideration prompted the current authors to choose a laparoscopic approach first. With assurance gained by viewing the mass objectively and the diagnosis confirmed further by the frozen-section biopsy report, the current authors decided that it was safe to proceed with a myomectomy.

Despite various reviews, the etiology of the ascitic fluid in pseudo–Meigs' syndrome remains unknown; however it is assumed to share similar pathogenesis as Meigs' syndrome. ⁴ Meigs originally suggested that the ascitic fluid originated from leaky edematous fibromas. ¹ Some researchers have suggested that the ascites is produced either directly from the surrounding lymphatics or vessels as a result of tumor compression, hormonal stimulation, or tumor torsion. With torsion ruled out in the current case, it was probable that mechanical tumor irritation with increased peritoneal pressure from the ascites might have caused further fluid production via peritoneal inflammation. ¹⁷

Although rare, elevation of serum CA-125 with leiomyomas have been reported previously.^18,19 In Brown et al.'s case report of a broad ligament leiomyoma, the researchers stated that it was not certain if the CA-125 elevation was simply due to the distension of the peritoneum by the leiomyoma or if this elevation was due to the more-widespread involvement of all the associated peritoneal and pleural surfaces. ²⁰

Liou et al. found that expression level of CA-125 correlated with the ascites volume in patients with Meigs' syndrome. ²¹ In addition, Pauls et al. reviewed 14 cases of leiomyomas presenting as pseudo–Meigs' syndrome and found a positive correlation between the presence of ascites and elevated levels of CA-125. ⁶ In a case of pseudo–pseudo Meigs' syndrome (PPMS) originally described by Tjalma in 2005, ²² a constellation of ascites, pleural effusion, and raised CA-125 levels were seen in a patient with systemic lupus Erythematosus (SLE). Although PPMS is rare, subsequent case reports described similar associations between ascites and raised CA-125 levels.^23–26 The exact pathophysiology of ascites and elevated CA–125 in pseudo–Meigs' syndrome is still poorly understood. This occurrence could be due to peritoneal inflammation and secretion from mesothelial cells or effusion as has been illustrated, but it is also likely to result from a complex combination of factors, including mechanical, biochemical, and/or immunologic factors.^22–26

It is interesting to note as is typical in pseudo-Meigs' or Meigs' syndrome, the current patient has had no recurrence of the ascites and her CA-125 levels became normalized postoperatively. This is in contrast to what occurs in PPMS, which has no association with either benign or malignant pelvic masses.

Therefore, findings of a heterogeneous solid pelvic mass in association with ascites, pleural effusion, and elevated serum CA-125 should not steer physicians away from thinking of the possibility of a patient having a benign condition.^27–33

Conclusions

A uterine leiomyoma presenting as pseudo–Meigs' syndrome must be kept in mind and this should be considered as a differential diagnosis when a solid pelvic mass with ascites, pleural effusion, and an elevated level of serum CA-125 are encountered. There is a role for laparoscopic investigation and laparoscopic myomectomy can be attempted; this has proven to be feasible.