Linitis Plastica-like Metastases to the Gastrointestinal Tract on Cross-Sectional Imaging

Area of Science:

• Radiology
• Gastroenterology
• Oncology

Background:

• Linitis plastica (LP) describes diffuse mural tumor infiltration causing loss of organ distensibility.
• While most common in the stomach, LP can occur elsewhere in the GI tract and mimic primary tumors.
• Extragastrointestinal primaries, especially breast, bladder, and prostate cancers, can present with LP-like metastases.

Purpose of the Study:

• To review the cross-sectional imaging features of gastrointestinal (GI) metastases with a linitis plastica (LP) pattern.
• To highlight diagnostic challenges and differential diagnoses for LP-like GI metastases.
• To emphasize the radiologist's role in identifying these metastases and guiding biopsy strategies.

Main Methods:

• Review of cross-sectional imaging findings in GI metastases exhibiting an LP pattern.
• Case illustrations from various primary tumors.
• Discussion of key imaging features, including the malignant target sign.

Main Results:

• LP-like GI metastases show circumferential wall thickening, luminal narrowing, and disproportionate submucosal/serosal enhancement.
• The malignant target sign, characterized by enhanced submucosa/serosa, differentiates from the benign target sign.
• Imaging findings can include obstruction and peritoneal carcinomatosis; mucosa may be spared, leading to potential biopsy challenges.

Conclusions:

• Radiologists play a crucial role in suspecting and diagnosing LP-like GI metastases.
• Accurate diagnosis is critical as management differs significantly from primary GI tumors or benign conditions.
• Recognition of the LP pattern can aid in identifying unknown primary tumors and directing biopsies.