An unusual initial presentation of mantle cell lymphoma arising from the lymphoid stroma of warthin tumor

BACKGROUND: Warthin tumors presenting concomitantly with a lymphoma is vanishingly rare with only 15 reported cases in English literature. Herein, we report an unusual initial presentation of a mantle cell lymphoma involving the lymphoid stroma of a Warthin tumor. CASE PRESENTATION: A seventy-seven year old otherwise healthy gentleman with a 50-pack year smoking history presents with a slowly enlarging left cheek mass. CT scan of the neck demonstrated a left parotid gland tumor measuring 3.4 cm in greatest dimension. He underwent a left superficial parotidectomy, with subsequent histopathologic examination revealing a Warthin tumor with extensive expansion of the lymphoid stroma. Flow cytometric, immunohistochemical, and cytogenetic studies of the stromal component of the tumor confirmed the presence of a mantle cell lymphoma. Clinical staging demonstrated stage IVa disease, and was considered to be at low to intermediate risk due to the slow growth of the parotid lesion. The patient is undergoing close follow up with repeat PET-CT scans at six months. CONCLUSION: To the best of our knowledge, this is the first well documented collision tumor between mantle cell lymphoma and a Warthin tumor. This case also brings to light the significance of thorough evaluation of the lymphoid component of Warthin tumor

Influence of decreasing solvent polarity (1,4-dioxane/water mixtures) on the stability and structure of complexes formed by copper(II), 2,2`-bipyridine or 1,10-phenanthroline and guanosine 5`-diphosphate : evaluation of isomeric equilibria

The stability constants of the 1 : 1 complexes formed between Cu(Arm)2+, where Arm = 2,2`-bipyridine or 1,10-phenanthroline, and guanosine 5`-diphosphate (GDP)3- or its monoprotonated form H(GDP)2- were determined by potentiometric pH titrations in water and in water containing 30 or 50 stability of the binary Cu(GDP)- complex is enhanced due to macrochelate formation of the diphosphate-coordinated Cu2+ with N7 of the guanine residue as previously shown. In Cu(Arm)(GDP)- the N7 is released from Cu2+ and the stability enhancement of more than one log unit in aqueous solution is clearly attributable to intramolecular stack formation between the aromatic rings of Arm and the guanine moiety. Indeed, stacked isomers occur to more than 90 with open unstacked forms. Surprisingly, the same formation degrees of the stacks are observed for Cu(Arm)(dGMP) complexes, where dGMP2- = 2`-deoxyguanosine 5`-monophosphate, despite the fact that the overall stability of the latter species is by about 2.7 log units lower. In 1,4-dioxane-water mixtures stack formation is drastically reduced, probably due to hydrophobic solvation of the aromatic rings by the ethylene bridges of 1,4-dioxane. The relevance of these results regarding biological systems is indicated

Pharmaceutical solid-state characterisation techniques

The solid state of a pharmaceutical material impacts on every aspect of its formulation; from solubility and thermodynamic stability to tabletability and flowability. Due to this fundamental connection characterising the solid state is key to providing the information necessary to reduce possible future manufacturing or formulation issues, which critically cuts drug product development costs and time. In this chapter a summary of the importance of the solid state and solid form screening in the pharmaceutical industry is presented. This is followed by an introduction to some of the solid state characterisation techniques routinely utilised in the pharmaceutical industry together with examples of the information provided by each