Comparison of p63 and p40 (ΔNp63) as Basal, Squamoid, and Myoepithelial Markers in Salivary Gland Tumors.

p40 is selective for ΔNp63 isoforms and appears to be more specific for squamous differentiation than p63. Its performance as a basal/myoepithelial marker in salivary gland tumors has only rarely been addressed in the literature. We thus compared the performance of p63 and p40 (ΔNp63) immunohistochemical stain as markers of basal, squamoid, and myoepithelial differentiation in 105 salivary gland tumors selected from our archives. The neoplasms were categorized according to their presumed phenotype as ductoacinar (n=45), biphasic (dual ductal and myoepithelial/basal differentiation, n=44), purely myoepithelial (n=5), and excretory duct phenotype (n=11). Only nuclear staining for p63 and p40 was considered positive. Distribution of staining was scored as: 0 (no staining), 1+ (1% to 25%), 2+ (26% to 50%), 3+ (51% to 75%), and 4+ (76% to 100%). Intensity was scored as weak, moderate, or strong. p63 and p40 highlighted the basal and myoepithelial cells in normal salivary gland tissue as well as basal/myoepithelial/squamoid elements in biphasic tumors, purely myoepithelial tumors, and excretory duct type tumors (4+ with strong staining for p63, and moderate staining for p40). All ductal tumors were negative for p40. However, 13/13 polymorphous low-grade adenocarcinoma/cribriform adenocarcinomas of salivary gland, 7/9 canalicular adenomas, and 3/5 mammary analog secretory carcinomas showed some degree of p63 staining. Thus, we confirm that p40 is a more specific basal/myoepithelial/squamoid marker than p63 in salivary gland tumors. A subset of ductal tumors show a discordant p63+/p40- immunoprofile that can be a pitfall if not recognized, but may also help distinguish these tumors from truly biphasic tumors and myoepithelial tumors.

Is Computed Tomography an Adequate Imaging Modality for the Evaluation of Juvenile Ossifying Fibroma? A Comparison of 2 Imaging Modalities (Computed Tomography and Magnetic Resonance Imaging).

PURPOSE: Given the problems of overuse of medical technology and the current burden of health care cost in the United States, it is important to establish clear imaging guidelines to diagnose conditions such as juvenile ossifying fibroma (JOF). This study compared the efficacy of computed tomography (CT) and magnetic resonance imaging (MRI) in the evaluation of JOF and thus could aid establishing such guidelines. MATERIALS AND METHODS: Radiologic criteria were established by 2 radiologists to compare the efficacy of CT and MRI in the evaluation of JOF. The following parameters were compared: presence of a well-defined corticated border, presence of a well-delineated internal calcified component, fluid-to-fluid levels, and anatomic extent of the lesion. Six patients diagnosed with JOF of the craniofacial bones from 2002 to 2013 had preoperative CT and MRI studies available for review. RESULTS: After review of CT and MRI images, fluid-to-fluid levels and anatomic extent of the lesions were comparable on CT and MRI. However, the corticated borders and the internal calcified component were better defined on CT images, which also enabled for distinction between the 2 subtypes of JOF. No MRI characteristics were identified that allowed for this distinction. CONCLUSION: Based on these findings, CT is an adequate and preferable imaging modality in the evaluation of JOF.