Solitary Temporal Plasmocytoma: A Case Report

Introduction: Solitary plasmacytoma is a malignant plasma cell tumor that is much rarer than multiple myeloma. The location in the vault of plasmacytoma is extremely rare. We report the case of a plasmacytoma of the cranial vault in a 53-year-old adult. Observation: A 53-year-old man consulted for tinnitus, left hypoacusis and trigeminal neuralgia of the left V2 and V3, which had been evolving for one year and was aggravated one month later by the appearance of a left temporal swelling with decreased visual acuity on the left. The MRI confirmed the existence of a lesional process of the temporal vault, in T1 iso signal, T2 hypersignal and flair, intensely and heterogeneously enhanced after injection of gadolinium. Anatomopathological study revealed a solitary temporal plasmacytoma, which was referred to oncology for further management. Discussion: Plasmacytoma is defined as an isolated malignant plasma cell tumor without clinical, biological, or radiological signs of Myeloma. Craniocerebral localization is rare and constitutes only 0.7% of all solitary plasmacytomas. Conclusion: Cranial plasmacytoma is a rare tumor that should be investigated for associated myeloma. Although the imaging appearance is not very specific, plasmacytoma should be considered in the differential diagnosis of any invasive lytic lesion of the cranial vault.

Diffuse Hepatic and Spleen Uptake of Tc-99m MDP on Bone Scintigraphy Resembling Liver-Spleen Scintigraphy in a Patient of Plasma Cell Tumor

The present case demonstrates a diffuse intense hepatic and, to a lesser degree, spleen, Tc-99m MDP uptake on a routine bone scintigraphy resembling liver-spleen imaging. A 49-year-old female with a history of anaplastic plasma cell tumor and suffering from bone pain was referred for bone scintigraphy to evaluate possible bone metastases. The bone scintigraphy showed diffuse hepatic and spleen uptake of Tc-99m MDP resembling liver-spleen imaging. Furthermore, bone uptake of Tc-99m MDP was significantly diminished and there were no abnormal foci throughout the skeleton. The bone scintigraphy of the present case of an anaplastic plasma cell tumor suggests the possible presence of amyloidosis.

Global gene expression profiling in mouse plasma cell tumor precursor and bystander cells reveals potential intervention targets for plasma cell neoplasia

Tumor progression usually proceeds through several sequential stages, any of which could be targets for interrupting the progression process if one understood these steps at the molecular level. We extracted nascent plasma cell tumor (PCT) cells from within inflammatory oil granulomas (OG) isolated from IP pristane-injected BALB/c.iMycEμ mice at 5 different time points during tumor progression. We used laser capture microdissection to collect incipient PCT cells and analyzed their global gene expression on Affymetrix Mouse Genome 430A microarrays. Two independent studies were performed with different sets of mice. Analysis of the expression data used ANOVA and Bayesian estimation of temporal regulation. Genetic pathway analysis was performed using MetaCore (GeneGo) and IPA (Ingenuity). The gene expression profiles of PCT samples and those of undissected OG samples from adjacent sections showed that different genes and pathways were mobilized in the tumor cells during tumor progression, compared with their stroma. Our analysis implicated several genetic pathways in PCT progression, including biphasic (up- and then down-regulation) of the Spp1/osteopontin-dependent network and up-regulation of mRNA translation/protein synthesis. The latter led to a biologic validation study that showed that the AMPK-activating diabetes drug, metformin, was a potent specific PCT inhibitor in vitro.