Dermoscopic and reflectance confocal microscopy findings in palisaded encapsulated neuroma (PEN): report of two histologically confirmed cases.

These medical case reports discuss the reflectance confocal microscopy (RCM) features of palisaded encapsulated neuromas (PEN), a relatively uncommon benign neural tumor that predominantly manifests in middle-aged females, most notably on the facial cheek. These reports feature two middle-aged females who both presented with concern for progressively enlarging cheek papules. Dermoscopy revealed the presence of symmetrical, dome-shaped papules with arborizing blood vessels that were not in sharp focus. RCM images revealed a honeycomb pattern, replete with follicular openings and slight papillary dermal fibrosis. Horizontally oriented blood vessels and vellus hair follicles, as well as prominent vellus hair bulbs were noted. The findings were initially perplexing and collectively raised the possibility of a skin adnexal neoplasm. However, subsequent biopsy confirmed a diagnosis of PEN in both cases. In retrospect, the neoplastic cells were beyond the imaging depths of RCM but the observed changes, including alterations in hair follicles on confocal microscopy, were likely due to pressure from the underlying tumor. Consideration of these features aids in diagnosing this unique yet benign neoplasm.

A case of shiitake dermatitis in the United States.

A 65-year-old male presented to our dermatology clinic with a two-day intensely pruritic rash covering his back. The lesions were predominantly on his chest, upper extremity, and back. He denied any prior history of similar rashes and his past medical history was non-contributory. A detailed exposure history revealed the patient had eaten Shiitake mushrooms for dinner 48 hours previously. Physical examination showed a truncal dominant rash. Close-up examination confirmed the papulovesicular nature of the rash with multiple small vesicles grouped both along the breadth and length of each linear streak on an erythematous background. Biopsies showed spongiosis with micro-vesiculation. Blood work showed a nominal CBC and CRP/ESR and serum IgE. The patient was put on topical steroid and the rash resolved in one week. With increasing mushroom consumption [1], cognizance of this etiology avoids a diagnostic 'odyssey' and prevents recurrence of this very characteristic rash.

Evaluation of Diagnostic Utility of a High-Risk Human Papillomavirus PCR Test on Formalin-Fixed, Paraffin-Embedded Head and Neck Tumor Tissues.

The increasing prevalence of high-risk human papillomavirus (HR-HPV)-associated head and neck squamous cell carcinoma (HNSCC) has prompted strong clinical demands for detecting HR-HPV directly in the tumor. Although p16 immunohistochemistry (IHC) has been the standard testing method, it has limitations including false positivity, lack of sensitivity in low tumor cell samples such as fine-needle aspirate (FNA), and its subjectivity. We developed a modified method based on a commercial automated HR-HPV PCR assay and evaluated the performance characteristics and the diagnostic utility of this assay for direct HR-HPV detection in the HNSCC samples. HNSCC formalin-fixed, paraffin-embedded blocks were retrieved from archives including 44 excisions, 63 biopsies, and 16 FNAs. Tissue slices were trimmed from the blocks, deparaffinized, lysed, and loaded on the commercial automated platform for HR-HPV PCR. All specimens had a concurrent p16 IHC performed. The PCR assay showed high concordance with the p16 IHC (96%; 99/103) and excellent positive agreement (91.5%) and negative agreement (100%). In addition, the PCR assay provided more conclusive results in samples with equivocal p16 IHC results. The modified commercial automated HR-HPV PCR test is a labor-efficient, quick, reliable, sensitive, and specific method for detecting HR-HPV in formalin-fixed, paraffin-embedded samples. This assay also showed excellent diagnostic utility in samples with equivocal p16 IHC results, including FNA cell blocks.

A Rare Case of Pediatric Chronic Myelogenous Leukemia Presenting With Severe Thrombocytosis Without Leukocytosis.

Pediatric chronic myelogenous leukemia is uncommon. We report a pediatric patient with chronic myelogenous leukemia presenting with a normal white blood cell count and no circulating immature myeloid cells. The patient presented with extreme thrombocytosis (platelet count range: 2175-3064 × 109/L) noted incidentally. No splenomegaly was found. Examination of the bone marrow aspirate revealed normal cellularity and normal myeloid: erythroid ratio with marked megakaryocytic hyperplasia. Molecular studies on the bone marrow aspirate detected both the major BCR/ABL1 p210 fusion transcript (9280 copies; p210/ ABL1 ratio: 38.2%) and the minor p190 transcript (below limit of quantitation). The platelet count normalized within 2 weeks after treatment with the second-generation tyrosine kinase inhibitor dasatinib. Follow-up after 3 months revealed a 1.87 log reduction in p210 transcripts compared to diagnosis and no detectable p190 transcripts. This case highlights the need to include BCR/ABL1 fusion testing to accurately diagnose pediatric patients presenting with isolated thrombocytosis.

The role of serum amyloid A staining of granulomatous tissues for the diagnosis of sarcoidosis.

BACKGROUND: Previous studies demonstrated that SAA staining of sarcoidosis granulomas was qualitatively and quantitatively different from other granulomatous diseases. These data suggest that positive SAA staining of granulomatous tissue may have adequate specificity to establish a diagnosis of sarcoidosis. Our objective was to determine the diagnostic specificity of SAA staining for sarcoidosis relative to other granulomatous disorders. METHODS: Pathological specimens demonstrating granulomatous inflammation were retrospectively identified at one institution, plus 4 specimens were obtained from New York City firefighters with biopsy-confirmed World Trade Center "sarcoidosis-like" pulmonary disease. Specimens were analyzed if specific diagnoses related to the granulomatous inflammation were confirmed through medical record review. SAA staining was performed using previously developed methods. Two pathologists, blinded to each other and the diagnoses, determined if the stained material was SAA positive or negative. Discordant results were adjudicated by the two pathologists. MEASUREMENTS AND MAIN RESULTS: 106 specimens were analyzed from 100 patients, with 36 biopsies (34%) from sarcoidosis tissues and 70 (66%) from other granulomatous disorders. The Cohen Kappa correlation between the two pathologists for SAA staining positivity was excellent (0.85, 0.73-0.98). The overall specificity of SAA staining for the diagnosis of sarcoidosis was 84% (59/70). The sensitivity was 44% (16/36). CONCLUSIONS: Although SAA staining of various granulomatous tissues was fairly specific for the diagnosis of sarcoidosis, the specificity was inadequate for SAA staining to be used as a diagnostic test for sarcoidosis in isolation. These data suggest that SAA production may not be a universal mechanism in the development of sarcoidosis.