Peritoneal Inclusion Cysts

Author Information

Chawla T*. Fernandes G**, Parulekar SV***
(* First Year Resident, *** Professor and Head, department of Gynecology and Obstetrics; * Associate Professor, Department of Pathology, Seth GS Medical College & KEM Hospital, Mumbai, India)


Peritoneal inclusion cysts are not very common. They may be found incidentally. They are usually reactive, but may be developmental in some cases. We present an unusual case that developed in response to tubal sterilization operation using silastic bands.


Peritoneal inclusion cysts are not very common. They are usually found in the reproductive age women. They are usually reactive, but may be developmental in some cases. The most common causes of reactive development of the cysts include pelvic surgery, infection, or endometriosis. We present an unusual case that developed in response to tubal sterilization operation using silastic bands.

Case Report

A 41 year old female, married for 26 years, para 3 living 3 abortion 1, with tubal ligation done 15 years back presented with complaints of menorrhagia for 6 months with soakage of 6 pads per day. It was also associated with passage of clots and dysmenorrhea. She had history of pelvic inflammatory disease 1 year back for which she was prescribed a course of doxycycline and metronidazole. There was no history of any bowel or  bladder related symptoms, no complaints of weight loss, and no other medical or surgical risk factors. Her general and systemic examination findings were within normal limits. The abdomen was soft. There was a mini-laparotomy tubal ligation scar above the pubis. A speculum examination showed Nabothian follicles on the cervix and healthy vagina. On per vaginal examination, the uterus was approximately 6-8 weeks size, mid-posed, the  fornices free and non tender. Her biochemical preoperative investigations, chest radiography and electrocardiogram were normal. Her hemoglobin was 10 g/dL. Abdominopelvic ultrasonography revealed 2 fundal leiomyomas of approximately 3 cm X 4 cm and 2 cm X 3 cm on the anterior and posterior uterine wall respectively. A vaginal hysterectomy was performed under spinal anesthesia. Three unilocular, translucent cysts measuring 1 cm X 0.5 cm, 0.5 cm X 0.5 cm, and 0.5 cm X 0.5 cm, containing clear fluid were present on the lateral wall of uterus on the isthmic portion of fallopian tube, very close to the silastic band applied to the tube for tubal sterilization. The postoperative period being uneventful. The comprehensive histopathological examination of the specimen revealed the cysts to be peritoneal inclusion cysts.

Figure 1. Simple hysterectomy specimen showing three unilocular, translucent cysts (yellow arrows) on the serosa of the left fallopian tube close to the cornu. The silastic band is seen nearby (black arrow).

Figure 2. Cut surface of the cyst showing a smooth inner wall (white arrow). A leiomyoma is also seen (black arrow).

Figure 3. Microphotograph showing a cyst within the serosa. Smooth muscle bundles of the myometrium are seen to the right. (H&E x 50)

Figure 4. Microphotograph showing a tiny microscopic cyst in the vicinity of the larger cyst. (H&E x 50)

Figure 5. Microphotograph showing cyst wall lined by a single layer of hobnail shaped cells resembling mesothelial cells. (H&E x 1000)

Figure 6. Microphotograph showing cyst wall lined focally by multilayered cuboidal cells with bland nuclear features. (H&E x 1000)


Peritoneal inclusion cysts usually occur in women in the reproductive age group. Most of them are reactive in origin.[1,2] Some of those located in the mesentery of the small intestine, mesocolon, retroperitoneum, spleen or kidney may be developmental.[3] They arise by invagination of the serosa. They may be incidental findings at laparotomy. They are usually small, single or multiple, unilocular, thin-walled, translucent cysts. They may be attached or lie free in the peritoneal cavity. They usually lie beneath the serosal surface. They have a smooth lining of a single layer of flattened, benign looking mesothelial cells. Their contents vary from watery and yellow to gelatinous.[4] Multilocular cystic masses may be very large, measuring up to 20 cm in diameter. They are usually attached to the pelvic organs. They usually cause lower abdominal pain and/or palpable mass. They may mistaken for a cystic ovarian tumor. Their septa and walls may contain abundant fibrous tissue. Their contents may be like those of the unilocular cysts, or they may be bloody. They are usually lined by a single layer of flat to cuboidal cells, though occasionally it may be of hobnail-shaped mesothelial cells showing bland nuclear features.[5] Some reactive atypia may be found. Other occasional features include small papillae, cribriform pattern, squamous metaplasia, intra- and extracellular hyaline bodies, adenomatoid tumor-like patterns, an infiltrative appearance.[6]
About 5% cases have a history of a prior abdominal operation, pelvic inflammatory disease, or endometriosis. This supports the reactive theory of genesis of these cysts. The case presented here had these cysts very close to tubal sterilization with silastic band on one fallopian tube. Silastic is inert chemically and does not elicit any tissue reaction. That explains the rare occurrence of this condition in association with tubal sterilization with silastic bands. It was unusual that she had such cysts on only one fallopian tube, though silastic bands had been applied to both the tubes. She had pelvic inflammatory disease in the past too. But we feel it was unlikely to be the cause, because it had been a single episode of acute infection, which had been controlled with antibiotics. A chronic infection is more likely to cause development of such cysts. Another factor favoring the sterilization procedure over the pelvic infection as the cause of these cysts in this patient was the location of the cysts only on the fallopian tube, which was otherwise healthy in appearance. Pelvic infection would have caused development of the cysts on other pelvic structures too, and the tubes would have shown effects of the past infection. Though a malignant behavior is not seen in multilocular cysts, about 5% of them the recur one or more times, after months to many years. These could be development of new cysts as a result of the irritation caused by the operation for excision of the previous cysts.


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5.        Ross MJ, Welch WR, Scully RE. Multilocular peritoneal inclusion cysts (so-called cystic mesotheliomas). Cancer 1989;64:1336-1346.
6.        Lamovec J, Sinkovec J. Multilocular peritoneal inclusion cyst (multicystic mesothelioma) with hyaline globules. Histopathology 1996;28:466-469.


Chawla T, Fernandes G, Parulekar SV. Peritoneal Inclusion Cysts. JPGO 2014. Volume 1 Number 12. Available from: