Rare cause of ovarian mass

Abstract

Pelvic actinomycosis is a rare entity that occurs almost exclusively in women, the presentation of which is usually non-specific and variable. Pelvic actinomycosis is almost always associated with the use of an intrauterine contraceptive device (IUD). Pelvic actinomycosis unrelated to IUD use is almost always associated with previous surgical procedures. The symptoms, clinical signs and radiological findings are usually non-specific, mimicking an ovarian malignancy. So an awareness of this rare condition and a proper diagnosis can avoid unnecessary surgeries because these cases can be treated with a prolonged course of antibiotics. We present a case of pelvic actinomycosis which masqueraded as an ovarian malignancy.

Background

Pelvic actinomycosis is a rare entity that occurs almost exclusively in women, the presentation of which is usually non-specific and variable.¹ The radiological findings are often non-diagnostic and a definitive diagnosis of this special condition can usually be made only histopathologically. Pelvic actinomycosis is almost always associated with the use of an intrauterine contraceptive device (IUD).² In a systematic review by Alejandra García-García et al, 12 cases of pelvic actinomycosis were reported unrelated to IUD use³ and all patients had a prior pelvic procedure.² We present an interesting case of pelvic actinomycosis which is not associated with a prior IUD use and a pelvic procedure.

Case presentation

A 44-year-old multiparous perimenopausal woman presented at the Gynaecology department, Tirunelveli Medical College Hospital with complaints of lower abdominal pain for 1 month and also a history of amenorrhoea of 4 months followed by abnormal bleeding per vaginum for 2 days. She denied any history of abnormal vaginal discharge. She did not give a history of IUD insertion or any recent invasive surgical procedure except for a laparoscopic tubal ligation done 20 years back. She was not on any chronic immunosuppressive drugs. A right adnexal mass was felt on pelvic examination and she had no significant lymphadenopathy. An ultrasonogram of the pelvis revealed a thick walled multiloculated cystic mass of 5.8 cm×5 cm with echogenic foci inside, in the right adnexa. Serum CA-125 was elevated at 245.5 U/L, which is more than a cut-off value of 200 U/L. Furthermore, a contrast CT evaluation of abdomen and pelvis was done which showed a multiloculated cystic mass with thick septations and solid areas about 6 cm in size arising from the right ovary but the left ovary, uterus and liver were normal (figure 1). A malignant right ovarian tumour was suspected based on the CT scan findings and the elevated serum CA-125 values. Hence, the patient was referred to the surgical oncology department for further management.

Figure 1.

CT image showing the uterus with right ovarian mass.

We took her up a staging laparotomy and was found to have a right ovarian tumour of about 8 cm×6 cm in size densely adherent to the right cornu of the uterus and the pouch of Douglas with infiltration of the tumour into the bladder. The right ureter and right iliac vessels were also pulled into the right ovarian mass due to dense fibrosis. Liver and rest of the viscera were normal. A type 1 hysterectomy, bilateral salphingo-oophorectomy, including a partial cystectomy was done followed by bilateral pelvic lymphadenectomy and omentectomy done as part of the staging procedure.

On pathological examination, cut section of the right ovary showed an intact capsule with fibrinous exudates inside. It was predominantly solid with small cystic spaces measuring 1.5 cm in diameter filled with gelatinous material (figure 2). There was another globular soft tissue mass in the right broad ligament. Myometrium also showed friable soft tissue foci in the fundus. Much to our surprise, the sections studied from the friable solid areas in right ovary, broad ligament and myometrium showed bacterial colonies characterised by radiating granular basophilic filaments surrounded by eosinophilic material (Splendore-Hoeppli phenomenon) (figure 3). Hence, a diagnosis of pelvic actinomycosis involving the right ovary, right broad ligament and the uterus was made. There was no evidence of malignancy in the resected specimen. She was started on intravenous penicillin group of antibiotics and she is currently under treatment.

Figure 2.

Cut section of the right ovary showing an yellow colour.

Figure 3.

Splendore-Hoeppli phenomenon.

Outcome and follow-up

Presently, our patient is on oral antibiotics and is asymptomatic.

Discussion

Actinomycosis is a rare granulomatous suppurative disease with pelvis being the rarest area of presentation. About 85%–90% of the cases of pelvic actinomycosis have an association with the use of IUD, presenting as pelvic tumour syndrome or pelvic inflammatory disease.² Actinomyces are normally present in the gut and oropharynx. Inoculation of the vagina with stool or saliva in combination with trauma induced by the foreign body such as an IUD may allow the actinomyces to enter tissues.⁴ Actinomyces are easily detected by Papanicolaou-stained cervicovaginal smears and are present in as many as 25% of symptomatic women using IUDs.⁵

Disruption of mucosal barrier plays a key role in the pathogenesis of actinomycosis.⁶ One of the features of actinomycosis is that it secretes proteolytic enzymes which disrupts tissue planes and invades the nearby tissues thereby mimicking a malignant process.⁷ Pelvic actinomycosis unrelated to IUD is rare and are often related to other risk factors such as previous surgeries or any prior pelvic procedure.^{2 8} In our case, there was a history of laparoscopic tubal ligation. Only one more case has been reported so far without history of IUD insertion and a history of laparoscopic tubal ligation.⁹ Seligman et al, in their review of pelvic actinomycosis state that in pelvic actinomycosis not associated with IUD, the primary focus was in ileocaecal region, colon, rectum or haematogenous spread from an extragenital site and uterus is involved in less than 10% of cases.¹⁰

The gold standard for diagnosis of actinomycosis is culture from the affected tissues, but actinomyces species is a fastidious anaerobic bacterium which requires 2–3 weeks to culture with a failure rate of 50%.⁸ Usually, actinomycosis is characterised by the histopathological finding of ‘sulphur granules’. The sulphur granules, which are named for their yellow colour, represent tangled filaments of actinomyces species.¹¹ These granules are made up of bacterial elements and tissue debris.¹²

Imaging modalities like ultrasound and CT are non-specific for the diagnosis. Still, imaging findings like strong enhancement in the solid part of the mass after contrast administration, small rim-enhancing abscesses within the mass and extensive inflammatory extensions may help in making a preoperative diagnosis.¹³ The CT findings of this patient did not conform with pelvic actinomycosis. Due to the presence of prominent fibrotic tissue, the inflammatory strandings and the solid component of the mass tend to demonstrate intermediate to low signal intensity on T2-weighted MR images.¹³ CT or ultrasound can be used to obtain a tissue sample if the diagnosis is made preoperatively. A few cases have been reported in literature where a sample was obtained with image guidance and surgery was avoided.^{12 14–18} Moreover, serum CA-125 can be elevated in 30% cases of the pelvic inflammatory disease.

High-dose intravenous penicillin injection is the treatment of choice. Tetracycline, clindamycin and erythromycin can alternatively be used for patients allergic to penicillin.¹⁹ Even then, there is a role for surgical management to exclude malignancy and to treat cases who do not respond to antibiotics.⁸ Usually, actinomycosis shows an excellent prognosis having low mortality if early diagnosis is made and proper treatment is given.²⁰ However, long-term observation and follow-up after treatment is required because relapse is quite common.²¹ Presently, our patient is on oral antibiotics and she is asymptomatic.

Learning points.

• Pelvic actinomycosis, even though rare, should be considered in the differential diagnosis of ovarian malignancy especially when any of the following factors such as prior history of insertion of intrauterine device, prior pelvic procedure like hysteroscopy, history of appendicitis or appendicectomy with spillage of contents or chronic use of immunosuppressive agents is present.

• Preoperative diagnosis is often challenging due to non-specific clinical symptoms, signs and radiological findings. Nevertheless, a history of pelvic pain and a CT finding of an ill-defined, infiltrating intensively enhancing mass, crossing adjacent tissue planes and invading adjacent structures should arise the suspicion of pelvic actinomycosis.

• Whenever there is a strong suspicion, the diagnosis should be confirmed with image-guided needle biopsy and a culture for actinomycosis, because a proper diagnosis can avoid unnecessary surgery.

• Every oncologist should be aware of this ‘Great Pretender’ while dealing with ovarian malignancies.