Diffuse large B-cell lymphoma arising primarily at the stoma after bladder reconstruction using ileal conduit

Area of Science:

• Oncology
• Pathology

Background:

• Lymphoma, specifically diffuse large B-cell lymphoma (DLBCL), can present in various locations.
• Stomal sites, often resulting from surgical procedures like bladder reconstruction, are typically monitored for complications but rarely associated with primary malignancy.

Observation:

• A 76-year-old male presented with a several-week history of stomal swelling.
• Biopsy of the stoma revealed diffuse infiltration by large lymphoid cells, immunophenotypically positive for CD20, bcl-6, and MUM1.
• The patient was diagnosed with diffuse large B-cell lymphoma, exhibiting a non-germinal center B-cell pattern.

Findings:

• Whole-body PET-CT scan confirmed the lymphoma was exclusively confined to the stomal site.
• The patient underwent bladder reconstruction utilizing an ileal conduit.
• This represents the first documented instance of lymphoma originating primarily at a stoma.

Implications:

• The occurrence of primary stomal lymphoma is exceptionally rare.
• Clinicians managing patients with stomas, particularly after bladder reconstruction, must maintain a high index of suspicion for stomal site lymphoma.
• Routine long-term surveillance protocols should incorporate vigilance for this unusual presentation to ensure timely diagnosis and treatment.