Significance of intracytoplasmic crystalline inclusions in plasma cells - a review with case discussion

Dense lymphoplasmacytic infiltrate in tissues pose diagnostic challenge to pathologists. Presence of intracytoplasmic crystalline inclusions in plasma cells has been strongly linked with B- cell lymphoproliferative disorders, although isolated reactive cases are also reported. We reviewed the literature and present clinical, morphological and immunohistochemical findings in a polyp of the cervix. The polyp showed extensive plasma cell infiltrate with needle shaped and elongated intracytoplasmic inclusions in many of them. These cells were positive for CD 79alpha, CD 138, kappa and lambda light chain ( equal proportions) and IgG. They were negative for cytokeratin, desmin, CD 20, CD 68, and IgA. Immunoprofile, laboratory data and clinical follow up were consistent with reactive nature of the lesion. This case highlights the fact that the presence of intracytoplasmic crystalline inclusions should not be considered pathognomonic of B-cell lymphoproliferative disorder.