Radiological Assessment of Gynecologic Malignancies ppt

Radiological

Assessment of

Gynecologic

Malignancies

Daniel J. Bell, MBChB*, Harpreet K. Pannu, MD

Patients with gynecologic malignancies are evaluated with a combination of clinical

and diagnostic imaging methods. Imaging with ultrasonography (US), computed

tomography (CT), and magnetic resonance (MR) has a role in detection of and charac￾terizing gynecologic masses, and can supplement clinical staging, help in preopera￾tive planning for surgery, and assess patients for tumor recurrence. US has

a primary role in detecting and characterizing endometrial and adnexal pathology.

The role of CT is primarily to stage malignancy and detect recurrence, although it

can also detect larger gynecologic masses. MR imaging has added specificity over

US for lesion characterization, superior contrast resolution for visualizing uterine and

adnexal masses, and is also useful for staging gynecologic malignancies. This review

focuses on the radiologic imaging of the 3 most common gynecologic tumors: endo￾metrial, cervical, and ovarian carcinomas.

ENDOMETRIAL CARCINOMA

Endometrial carcinoma is the most common gynecologic malignancy, with approxi￾mately 40,000 new cases diagnosed in the United States each year.1 Pathologically

and clinically, endometrial cancer is divided into 2 main subtypes: endometrioid

(Type I) and nonendometrioid (Type II) tumors. Endometrioid histology is seen in

80% to 90% of patients.2 Patients are usually perimenopausal and have risk factors

associated with increased estrogen exposure such as nulliparity, chronic anovulation,

and obesity. The tumors are confined, as a rule, to the uterus and have a good

A version of this article was previously published in PET Clinics 5:4.

Department of Radiology, Memorial Sloan-Kettering Cancer Center, 1275 York Avenue, New

York City, NY 10065, USA

* Corresponding author.

E-mail address: [email protected]

KEYWORDS

Gynecology
Computed tomography

Magnetic resonance imaging
Ultrasonography
Sonography

Malignancy

Obstet Gynecol Clin N Am 38 (2011) 45–68

doi:10.1016/j.ogc.2011.02.003 obgyn.theclinics.com

0889-8545/11/$ – see front matter
2011 Elsevier Inc. All rights reserved.

prognosis. On the other hand, nonendometrioid subtypes are seen in older multipa￾rous women, usually without increased estrogen exposure.3 The most common forms

are uterine papillary serous carcinoma and clear cell carcinoma. These tumors have

a high propensity for myometrial and vascular invasion as well as peritoneal carcino￾matosis, and carry a poorer prognosis than endometrioid carcinoma.4 Painless

bleeding is the most frequent presenting symptom of endometrial cancer. Effective

steps for the evaluation of patients’ postmenopausal bleeding (PMB) are transvaginal

sonography (TVS), endometrial biopsy (EMB), and hysteroscopy.5 Once malignancy is

detected, tumor bulk as well as local and distant spread can be assessed with imaging

before surgical staging.

Role of Imaging in Primary Tumor Assessment

The role of imaging is twofold: to evaluate the symptomatic patient for a possible

endometrial abnormality, and to characterize and stage disease in those with known

pathology. Initial evaluation uses US to assess endometrial thickness and appear￾ance. The normal endometrium is homogeneously hyperechoic and thin, but is thick￾ened and heterogeneous with hyperplasia, polyps, and cancer (Fig. 1). The consensus

statement from the Society of Radiologists in Ultrasound has defined an endometrial

thickness of 5 mm or greater on TVS as being abnormal in patients with painless

PMB.5 Using a threshold of 5 mm, the sensitivity of TVS approaches that of endome￾trial biopsy, and had a sensitivity of 96% for detecting an endometrial abnormality in

patients with cancer in a meta-analysis of 35 studies.6 The negative predictive value

(NPV) of TVS is high and can be used to obviate biopsy. However, the specificity is

decreased in patients who are on hormone replacement therapy or medications

such as tamoxifen. Also, endometrial thickening due to hyperplasia, polyps, fibroids,

and malignancy can be difficult to distinguish on routine TVS. Presence of an echo￾genic lesion with a vascular stalk favors a polyp while fibroids are hypoechoic or

heterogeneous and broad-based.

In equivocal cases, sonohysterography can be performed to better assess the

endometrium. With this technique, the endometrial cavity is distended with saline

through a small-bore catheter tip placed in the cervix while real-time TVS images of

the lining are acquired to assess for smooth versus irregular thickening and masses.

The endoluminal distention achieved aids in both the detection and characterization

of endometrial masses. In a study of 114 patients who had an abnormal sonohystero￾gram, 14% had a normal-appearing endometrium on routine TVS while the sonohys￾terogram showed polyps and/or submucosal fibroids (Fig. 2).7 Sonohysterography

detected the etiology of PMB in 70% of 98 patients for an overall sensitivity of 98%,

specificity of 88%, positive predictive value (PPV) of 94%, and NPV of 97%.8 The

appearance of endometrial cancer is variable, but includes thickening and a polypoid

mass.9 Using the criteria of a focal heterogeneous mass projecting into the endome￾trial cavity or focal thickening greater than 4 mm, a study of 88 women undergoing

sonohysterography detected endometrial cancer in 8 of 9 women positive for malig￾nancy at surgery for a sensitivity of 89%, specificity of 46%, PPV of 16%, and NPV

of 97%.10

Once endometrial malignancy is detected, preliminary staging can be done with

imaging before definitive surgical staging, which remains the standard of care for

endometrial carcinoma unless the patient is a poor surgical candidate. Surgical

staging involves hysterectomy, bilateral salpingo-oophorectomy, peritoneal washing,

and lymphadenectomy. The key factors are the histopathologic grade of the tumor

and degree of myometrial involvement. Adverse features are higher tumor grade

46 Bell & Pannu