Secondary linitis plastica of the rectum: EUS features and tissue diagnosis (with video)

Background: Luminal metastases to the GI tract may be seen at the time of the primary diagnosis or may represent evidence of a distant recurrence. Objectives: To determine the prevalence of rectal-wall metastases in patients undergoing an EUS and to describe the EUS features and yield of EUS-guided FNA (EUS-FNA) and Trucut biopsy (TCB). Design: A case series. Setting: A single tertiary-referral center. Patients: Patients undergoing lower GI (LGI) EUS from July 1, 2005, to October 31, 2007. Intervention: EUS-FNA and/or TCB. Main Outcome Measurements: EUS features and cytologic and/or histologic confirmation of secondary rectal linitis plastica. Results: Over the 28-month period, an LGI-EUS was performed in 598 patients with presumed primary rectal cancer, of whom 6 (1%) were diagnosed with rectal-wall metastases. The EUS features were that of diffuse, circumferential, hypoechoic wall-thickening that mimics that of linitis plastica, breaching the muscularis propria in all cases. EUS-FNA and/or TCB of the rectal wall or perirectal lymph node established a diagnosis in all cases. The primary cancers originated from the bladder (n = 3), breast (n = 1), stomach (n = 1), and a right forearm cutaneous melanoma (n = 1). The time interval from the initial primary cancer diagnosis to that of GI-tract rectal metastasis ranged from 0 days (simultaneous diagnoses) to 119 months (mean ± SD 49 ± 43 months). Limitations: Although firm EUS criteria of rectal-wall metastases cannot be established based on 6 patients alone, certain features may prove useful for the diagnosis in the clinical practice. Conclusions: EUS-FNA and/or TCB can confirm the diagnosis of secondary linitis plastica of the rectum.