Malignant melanoma: correlating abdominal and pelvic CT with clinical staging.

Abstract

Two hundred two patients with malignant melanoma underwent computed tomography (CT) scanning of the abdomen and pelvis. The frequency of metastases in the abdomen and pelvis was correlated with the site, level, and thickness of the primary tumor. The sites of the primary tumors were the trunk (70 patients), the lower extremities (37 patients), the upper extremities (33 patients), the head and neck (29 patients), the eye (nine patients), and the genitourinary tract (six patients). In 18 patients, the primary site could not be identified. In 96 patients, the level and thickness of the primary tumor, based on Clark and Breslow classifications, were correlated with the presence and extent of metastases. CT showed metastases in 122 patients (60%). The head and neck were the most common primary sites associated with metastases (79%), followed by the eye (77%) and genitourinary tract (67%). Thick lesions had the highest frequency of metastases (84%), compared with intermediate (50%) and thin (46%) lesions. Tumors classified as Clark level V had the highest frequency of metastases (87%).

Radiologic Imaging in Malignant Melanoma: A Review

“…The CT appearance is variable as the masses can be solid or predominantly cystic and are indistinguishable from other masses. The incidence of CT -diagnosed adrenal metastases was 11 %l and 23% in a series of patients, most of whom had primary lesions of Clark level III or greater [4,5].…”

“…Although there is little published data about the usefulness of computed tomography (CT) in detecting subcutaneous metastases, these lesions are readily identifiable as radiodense areas sharply contrasted against the surrounding radiolucent fat. At MD Anderson Hospital, in a group of patients most of whom had lesions thicker than Clark level III, 17 out of 122 (14 1Y(l) CT scans detected subcutaneous metastases [4].…”

“…The rate of metastases increased with increasing Clark level with 17% for Clark level III and 25% for both levels IV and V [5]. Shirkhoda found hepatic metastases in 38% of .a similar group of patients [4]. CT portography is a more sensitive augmented study which can routinely: detect metastases less than 1 ern in size but involves the placement of a superior mesenteric artery catheter [10,11].…”

“…Autopsy series reveal a nearly 50% incidence of bone metastases [2]. Bone is the sole focus of initial metastatic disease in only 3°1t) of patients and, com- bined with disease in other organs, presents as an initial site in II-17 0 ft. of cases [1,4]. In an analysis of 50 patients with 127 metastatic bone lesions, 80% of the lesions were axial, 38(1.. involving ribs, and only 10% of lesion-affected weight-bearing bones [7].…”

Staging of cutaneous melanoma

“…Although the yield of these tests (particularly abdominal CT) in detecting distant metastases in asymptomatic patients is low, they often identify false-positive abnormalities and thereby function as an important baseline for future studies in this high-risk population. CT scanning of the pelvis is generally performed for patients with a locoregional recurrence below the waist [56, 57], and the neck is generally imaged for a recurrence in the head and neck region. Nodal ultrasound is an alternative to CT scanning of the head and neck region.…”