Colonic in situ mantle cell lymphoma

Area of Science:

• Gastroenterology
• Hematology
• Oncology

Background:

• Mantle cell lymphoma (MCL) is a rare non-Hodgkin lymphoma.
• Primary gastrointestinal (GI) MCL is challenging to diagnose, especially in its early stages.
• The evolution of MCL from in situ to disseminated disease requires further investigation.

Observation:

• A 45-year-old male presented with rectal bleeding, with initial colon biopsies showing benign mucosa.
• Two years later, the patient developed ileocolic intussusception due to enlarged lymph nodes, revealing widespread MCL.
• Re-evaluation of initial biopsies identified cyclin D1-positive cells and t(11;14) translocation by FISH, indicating in situ MCL.

Findings:

• This report details the first identified case of in situ MCL in the GI tract.
• The initial diagnosis was missed due to subtle findings in random biopsies.
• FISH analysis and immunostains were critical for retrospective diagnosis and confirming the t(11;14) translocation characteristic of MCL.

Implications:

• Early detection of primary GI MCL is crucial for timely intervention and improved patient outcomes.
• This case underscores the importance of advanced diagnostic techniques like FISH and immunostains in identifying subtle lymphoid malignancies.
• Understanding the progression of in situ MCL is vital for refining diagnostic criteria and treatment strategies for GI lymphomas.