Russell body inflammatory polyp

Colorectal mucosa with Russell bodies is a reactive inflammatory lesion composed of mature plasma cells, known as Mott cells which contain multiple intracytoplasmic eosinophilic globules.

Russell bodies are eosinophilic spherical or globular cytoplasmic inclusions that accumulate in the rough endoplasmic reticulum of mature plasma cells. These plasma cells containing Russell bodies are also known as Mott cells.

Histologically, Russell body inflammatory polyp typically exhibits features of inflammatory polyp with expansion of lamina propria by Mott cells. The surface epithelium can be intact and show hyperplastic changes or can be partially or totally eroded with the presence of ulcer and granulation tissue.

The lamina propria in the colorectal Russell body lesions (including Russell body inflammatory polyp) shows expansion by inflammatory cells including variable composition of neutrophils, plasma cells, lymphocytes, and eosinophils.

However, the most prominent population is of Mott cells, which are plasma cells showing eccentric nuclei and containing numerous intracytoplasmic eosinophilic globules also known as Russell bodies.

Differential diagnosis

 signet ring cell carcinoma

• nuclear atypia
• positive for cytokeratin and mucicarmine.

 plasma cell neoplasms

• mucosa associated lymphoid tissue (MALT) lymphoma with plasmacytic differentiation
• plasmacytoma
  • cellular atypia
  • mitotic activity
  • monoclonal

See also

 digestive polyp

• rectal polyp

Open references

 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6087615/