Rapidly Growing Mucinous Cystadenoma in a 13‐Year‐Old Premenarchal Female: A Case Report

ABSTRACT

Mucinous cystadenomas are rare ovarian tumors in premenarchal girls but can present as rapidly growing large abdominal masses causing obstructive symptoms. Early recognition and timely surgical intervention, often requiring salpingo‐oophorectomy, are crucial to prevent complications. Awareness among pediatric healthcare providers is essential for accurate diagnosis and management.

1. Introduction

Tumors of the ovaries can be categorized as epithelial (cystadenoma, borderline cystadenoma, and cystadenocarcinoma), stromal (granulosa‐theca, Sertoli, and Leydig cells), and germ cell (undifferentiated and extraembryonic) [1].

Mucinous Cystadenomas (MCAs) make up 10%–15% of all ovarian tumors [2].

MCAs are tumors that are lined by mucin‐producing epithelial cells. They are typically unilateral (bilaterality is only seen in about 5%–10% of cases) with an average size of 10 cm; in rare cases, however, they can grow to exceed 30 cm. MCAs are most common in people between the ages of 45 and 65 years and are rarely seen in children and adolescents [1, 2, 3, 4].

Different abdominal masses and their characteristics can be distinguished with the use of imaging techniques of the abdomen, such as CT, ultrasonography, or magnetic resonance imaging [1].

While unilateral salpingo‐oophorectomy (USO) via laparotomy is currently the standard of care for benign MCAs, numerous studies have demonstrated the benefits and effectiveness of ovary‐conserving techniques in the surgical management of benign adnexal disease [5].

Hemorrhage, torsion, and rupture are the most frequent complications of benign ovarian cysts [4].

2. Case Report

A 13‐year‐old female was brought to the emergency department complaining of rapidly progressive abdominal enlargement (noted over the last 20 days), with a marked increase in size over the last 3 days before presentation. This acute presentation likely represents a complication of a pre‐existing lesion. The patient also had fever, right lower quadrant pain, and severe constipation.

Upon examination, the patient appeared dehydrated, with a distended abdomen and full flanks but no organomegaly. A digital rectal examination revealed no tenderness or visible mass.

Our patient was previously healthy, with no history of major illness or surgical operations. Crucially, the patient and her parents denied any prior history of chronic or intermittent lower abdominal pain, nonspecific swelling, or other gastrointestinal complaints on the right side of the abdomen before the onset of the acute symptoms 20 days prior to presentation. This suggests that the mass was either asymptomatic or too small to be noticed before the acute complication occurred.

Ultrasound imaging was done previously in another hospital and according to the medical report, it revealed a huge cystic lesion filled with cloudy fluid extending from the pelvis to the epigastrium and pushing the liver superiorly and the kidneys posteriorly and laterally. However, the images were unable to be acquired from the hospital.

3. Investigations and Treatment

A computed tomography (CT) scan was performed, which revealed a massive, unilocular cystic mass (measuring approximately 33 × 21 × 14) occupying the majority of the abdomen and pelvis. The mass was characterized by a thin, smooth wall with no internal septations or solid components detected (Figure 1). Due to the mass's undetermined origin or cause after performing imaging techniques and the patient's rapidly worsening obstructive symptoms, the pediatric surgery team at the hospital decided to do a midline incision laparotomy from the xiphoid process to the pubic symphysis.

FIGURE 1.

Computed Tomography (CT) showing a veiled cystic structure located above the uterus and extending upward between the intestinal loops, which appear to be pushed and compressed, reaching up to the right hypochondrium. The mass is approximately (21 × 33 × 14 cm) in size, without infiltrating the large vessels of the abdomen.

A large cystic mass was found originating from the right ovary. The mass was carefully dissected along with the round ligament, and the vascular vessels of the right ovary were ligated. A complete right salpingo‐oophorectomy was performed. The left ovary and fallopian tube were examined and appeared normal, the pelvis was clean, and no lymph node enlargement was found.

Gross pathological examination of the resected specimen (Figure 2) revealed a massive, encapsulated, ovoid mass. The outer surface of the cyst was smooth and glistening with evident superficial vasculature. The cyst wall was thin and uniform, and no solid areas or papillations were grossly visible.

FIGURE 2.

Macroscopic appearance of the mass measuring 21 × 33 × 14 cm.

The salpingo‐oophorectomy specimen was then subjected to histopathologic examination. The microscopic findings revealed a thin, smooth cyst wall lined by a single layer of bland mucinous epithelium with basally located small nuclei and columnar cytoplasm containing mucin. No cytological atypia or cellular anaplasia was observed (Figure 3). The diagnosis was concluded as a mucinous cystadenoma.

FIGURE 3.

A microscopic examination of the specimen revealed a thin, smooth cyst wall lined by a single layer of bland mucinous epithelium with basally located small nuclei and columnar cytoplasm containing mucin. No cytological atypia or cellular anaplasia was observed.

4. Outcome and Follow Up

The surgical procedure was completed without complications, and the patient was discharged in stable condition. A follow‐up assessment conducted 1 week later confirmed a satisfactory recovery with no reported complications.

5. Discussion

Ovarian tumors are so uncommon in women under 21 that their frequency has been estimated to be 2.6 instances per 100,000 females. Ovarian tumors in children make up 1%–1.6% of all childhood tumors. Epithelial ovarian tumors account for 10%–28% of all of these tumors in children and adolescents. Cystadenoma is the most prevalent benign epithelial ovarian mass, with 75% of cases being serous and 25% being mucinous [6, 7]. The patient in our case is 13 years old, which is a very rare age for ovarian masses.

Mucinous cystadenomas (MCA) are benign cystic ovarian tumors that arise from the ovary's surface epithelium and are defined by the synthesis of mucin. Mucinous tumors can be categorized as benign, borderline or low malignant, and invasive based on their histopathological subtyping. In general, 80% of MCA cases are benign, 10% have borderline or low malignant potential, and 10% are invasive. They most frequently occur in the third to sixth decades of life and often measure between 15 and 30 cm in diameter. The term “giant” ovarian cyst is most frequently used to describe ovarian cysts larger than 10 cm in diameter [3, 4].

The size of MCAs in children, however, differs from that in adults, as reading through medical literature on the different cases of MCAs in children and adolescents, it was found that their size (according to the largest dimension in cms) ranged from 3.8 to 26 cm in one paper which studied 14 cases in a hospital over 6 years from 2008 to 2014 [5]. Another review that studied different types of ovarian epithelial tumors in adolescents, including cystadenomas, concluded that their size ranged from 2.5 to 21 cm (mean is 11.7 cm); only a few studies were found in which the size exceeded those numbers [8]. The mass in our patient measured approximately (21 × 33 × 14 cm) in size, or 33 cm in the largest diameter, which is greater than most of the studies recorded in the medical literature.

They typically cause vague symptoms like pain, discomfort, bloating, or fullness in the abdomen, among other gastrointestinal complaints such as vomiting and constipation. Compression symptoms like dyspnea, early satiety, heartburn, and increased frequency of urination are also common complaints from increased pressure on the bladder, rectum, and blood vessels. Compression syndrome can result from increased pressure on the legs [3, 8].

Abdominal distension is the most common presentation of Ovarian Mucinous Cystadenoma (MCA). Usually, when there is a palpable abdominal mass, the first course of action is to perform an ultrasound scan. The transvaginal US and the transabdominal US are two vital instruments for assessing ovarian masses. A Computed Tomography (CT) or a Magnetic Resonance Imaging (MRI) scan is only carried out when the diagnosis is uncertain [9, 10].

Tumor markers are frequently utilized as part of the preoperative inquiry for differential diagnosis. They might also be measured postoperatively to ensure full excision of the mass and to detect relapse. The injured tumor epithelium releases the tumor markers CA‐125 and CA‐19.9 at the locations of adhesions and epithelial shearing pressures. The systemic circulation absorbs the ensuing elevated local concentration of tumor markers at these locations [9]. However, in the present case, preoperative tumor marker assays could not be performed due to the patient's critical clinical status and rapidly progressing obstructive symptoms, which necessitated immediate surgical intervention.

Cystectomy, ipsilateral oophorectomy, or salpingo‐oophorectomy are the typical treatments for ovarian tumors that are benign. Even though MCAs are often benign, their size usually prevents ovary‐sparing surgery from being performed. Usually, salpingo‐oophorectomy is the course of treatment for benign MCAs; no other medication is needed [9, 10].

The recurrence of mucinous cystadenoma is not as uncommon as the literature suggests. Therefore, the tumor should be treated thoroughly and completely [9]. Which further supports the choice of salpingo‐oophorectomy.

Operating on big masses is frequently linked to deadly outcomes, such as sepsis, pulmonary embolism, and heart failure. Thus, throughout the postoperative phase, proper monitoring and follow‐up are strongly advised. Other complications of MCAs include rupture of the cyst, which may lead to a condition known as pseudomyxoma peritonei, in which mucinous deposits fill the whole peritoneum [10].

The patient was discharged on the third postoperative day in stable condition. Clinical re‐evaluation conducted 1 week later revealed no complications.

Author Contributions

Zeina Marzouk: writing – original draft. Ayham Maidaa: writing – review and editing. Mohammad Obada Alsadi: writing – original draft. Rabwa Ibrahim: writing – original draft. Basil Daradkeh: writing – review and editing. Haneen Hussin: writing – review and editing. Khaledah Aladwan: writing – review and editing. Husam Dalati: writing – review and editing.

Funding

The authors have nothing to report.

Consent

Written informed consent was obtained from the patient's parent for the publication of this case report and any accompanying images.

Conflicts of Interest

The authors declare no conflicts of interest.

Marzouk Z., Maidaa A., Alsadi M. O., et al., “Rapidly Growing Mucinous Cystadenoma in a 13‐Year‐Old Premenarchal Female: A Case Report,” Clinical Case Reports 14, no. 1 (2026): e71805, 10.1002/ccr3.71805.

Data Availability Statement

Data sharing not applicable to this article as no datasets were generated or analysed during the current study.