Spectrum of Ovarian Incidentalomas: Diagnosis and Management

Abstract

Incidental ovarian lesions are asymptomatic lesions that are accidentally discovered during a CT or MRI examinations that involves the pelvic cavity or during a routine obstetric ultrasound study. Incidental ovarian masses are usually benign with a very low risk of malignancy yet underlying malignant pathology may be discovered during the diagnostic work-up of these lesions. Suspicion of malignancy is directly correlating with the increase in the patient's age, the increase in the size of the lesion, the presence of the solid components or thick septa and a high color scale of the ovarian mass. Following standard reporting and management protocols are essential to choose the proper work-up of these lesions to avoid unnecessary additional imaging and operative intervention. In this article, we will provide a review of the characteristic imaging features of some incidental and yet commonly encountered ovarian lesions. We will also summarize the recently published algorithms that are important for consistent reporting and standard management of these lesions.

Figure 1.

Ovarian fibroma incidentally discovered in a pregnant female during the routine obstetric work-up. (A) Transvaginal ultrasound that displayed gravid uterus of early pregnancy and concomitant an ovarian purely solid mass (M). (B) Ovarian mass which is showing scanty vascularity.

Figure 2.

(A) Transvaginal color-coded ultrasound image of an adnexal complex cystic mass that showed no internal vascularity found to be an ovarian endometrioma detected during the routine follow-up of pregnancy. (B) Grayscale ultrasound image of right ovarian simple cyst.

Figure 3.

A right ovarian functional cyst detected during the metastatic work-up of a breast cancer patient. (A) Post-contrast CT examination of the pelvis that is showing right adnexal cystic mass of slightly high attenuation value. (B) Transvaginal ultrasound in the same setting that shows the origin of the cyst to be ovarian and confirms the purely cystic nature of the mass. (C) MR imaging 6 weeks later showed no evidence of the right ovarian cystic mass and eventually supported the diagnosis of a functional ovarian cyst.

Figure 4.

A proved case of cervical carcinoma. Left tubo-ovarian complex was accidently discovered during MRI examination for cancer staging. (A) T ₂ weighted and (B) early post-contrast subtraction coronal MR images that show left adnexal tubular S-shaped fluid-filled structure of thick walls and involving the ovary (arrows) and showing mural contrast uptake noticed in (B). Notice a small sized proved cervical carcinoma (asterisks in image “A”).

Figure 5.

Peritoneal inclusion cyst post-myomectomy of a uterine fibroid: slices of T₂ weighted sagittal MR images that showed large thin-walled cystic mass overriding the uterus and engulfing the ovary (arrow). Notice a curvilinear bright signal at the anterior wall of the myometrium that represents iatrogenic changes from previous fibroid removal.

Figure 6.

Right ovarian endomterioma: (A) CT scanning of the pelvis showed a right ovarian cystic mass (arrow) with high attenuation components. (B) Transvaginal ultrasound showed a right sided thick-walled complicated ovarian mass with floating echogenic content (arrow) and no internal vascularity as seen in (C).

Figure 7.

A case of primary amenorrhea : (A) Sagittal MR T ₂ weighted image showed obstructed lower uterine segment (arrow) . Axial MR (B) T2, (C) T ₁ weighted without and (D) with fat suppression images showed distended uterine cavity with mixed collection of fluid/fluid leveling (arrow in B) and left ovarian endometriosis in the form of high intensity T1 weighted blood-filled cysts and internal dark signal of blood clots(arrow in C, D). Note, the presistent bright signal of the left ovarian endometriosis on the T1 weighted fat suppression sequence (D).

Figure 8.

Right ovarian teratoma: (A, B and C) Axial CT images showed right ovarian complex cystic mass with fat attention value and radio-opaque teeth therein (arrow). (D, E) Coronal reformatted CT images showed tuft of hair inside as well (arrow in D).

Figure 9.

Ovarian collision tumor (teratoma and mucinous cystadenoma) presented accidently during a post-menopausal checkup: (A) Axial MR T1- and B) T1 fat suppression weighted images that showed a bilocular cystic mass (M) with large mucinous component and small fat signal component justified by signal suppression in B). (C) Coronal MR T ₂ weighted image that represented the large mucinous component of the mass (M).

Figure 10.

Bilateral ovarian mucinous cystadenomas: (A) axial and B) coronal post-contrast CT images showed bilateral multilocular cystic ovarian masses of slightly high attenuation value (arrows). (C) T₂ weighted image and (D) post-contrast T ₁ weighted coronal MR images that showed bilateral high signal cystic ovarian masses with internal thin septations in (C) that displayed no contrast uptake and slightly bright T ₁ weighted signal in (D) (arrows).

Figure 11.

Bilateral ovarian fibromas: (A, B) post-contrast axial CT images showed bilateral small ovarian masses, right cystic and solid and left purely solid (circles). (C, D) Axial MR T ₂ weighted images showed the characteristic low T2 signal of the solid component of the masses (arrows) and steady homogeneous contrast uptake (arrows) comparable to that of the uterine myometrium as seen in the post-contrast images (E, F) .

Figure 12.

A case of cancer breast with Krukenberg tumors: (A, B) axial post-contrast CT images showed bilateral ovarian masses, the left one is purely cystic and the right one (M) showed cystic and solid component (arrowhead). (C) Reformatted contrast-enhanced CT and (D) MR T ₂ weighted coronal images displayed the solid component of the right ovarian tumor.