Acinic Cell Carcinoma of the Breast: Report of a Case With Immunohistochemical and Next-Generation Sequencing Studies.

Acinic cell carcinoma of the breast is a rare subtype of triple-negative breast cancer that recapitulates the appearance of tumors seen in salivary glands. We present the case of a 42-year-old woman with an irregular, nontender mass above the left nipple during routine obstetric appointment at 24 weeks gestation. She was subsequently diagnosed with triple-negative invasive ductal carcinoma of the left breast, Nottingham grade 3, via core needle biopsy. She was treated with neoadjuvant therapy (doxorubucin and cyclophosphamide) antenatally and paclitaxel in the postpartum period followed by left mastectomy with sentinel node biopsy. The carcinoma in the mastectomy specimen showed a spectrum of morphologic patterns with immunohistochemistry revealing strong positivity for alpha-1-antichymotrypsin, epithelial membrane antigen (EMA), lysozyme, and S100. The histomorphology paired with the immunoprofile led us to the diagnosis of acinic cell carcinoma. We retrospectively performed immunostains in the core biopsy specimen, which demonstrated GATA-3 and DOG-1 positivity. Next-generation sequencing of the postneoadjuvant specimen using a 70-gene panel revealed 2 single-nucleotide variant (SNV) mutations: tumor protein 53 (TP53) (c.747G>T) SNV mutation and rearranged during transfection (RET) (c.2899G>A) SNV mutation.

NUT (Nuclear Protein in Testis) Carcinoma: A Report of Two Cases With Different Histopathologic Features.

NUT (nuclear protein in testis) carcinoma (NC) is an aggressive carcinoma characterized by rearrangements of the NUT gene on chromosome 15q14. Histologically, it is a poorly differentiated carcinoma composed of monotonous, medium-sized, round cells with scant amphophilic or eosinophilic cytoplasm. Foci of abrupt keratinization are often seen. In this report, we compare the morphology of 2 cases of NC. The first case shows characteristic features of uniform, round epithelioid cells admixed with foci of abrupt keratinization. The second case demonstrates nests of epithelioid-polygonal cells that appear to be loosely cribriform within a mucoid stroma. Although considered rare, the actual incidence of NC may be underestimated, as it is likely that many go undiagnosed because the morphology deviates from what is typical. Our report demonstrates that NC should always be considered in any case of an undifferentiated carcinoma and should not be excluded if typical histologic and immunohistochemical features of squamous differentiation are lacking.

Sirtuin 1 activation stimulates mitochondrial biogenesis and attenuates renal injury after ischemia-reperfusion.

BACKGROUND: Renal ischemia-reperfusion (I/R) is a major contributor to delayed graft function after renal transplantation. The pathophysiology of I/R can be summarized by a primary energy deficit during ischemia and a secondary phase of oxidative stress and inflammation. Sirtuin 1 is an energy-sensing enzyme involved in regulating multiple cellular functions. We hypothesized that stimulating Sirtuin 1 would increase mitochondrial biogenesis thereby enhancing energy metabolism and attenuating I/R-induced renal injury. METHODS: Adult male rats were subjected to 60 min of bilateral renal pedicle clamping. SRT1720 (5 mg/kg body weight) or vehicle (20% dimethyl sulfoxide in saline) was administered intravenously at reperfusion. Blood and renal tissues were collected 24 hr after reperfusion. RESULTS: Posttreatment with SRT1720 significantly improved renal histologic architecture, decreased apoptosis, and reduced serum aspartate aminotransferase and creatinine levels compared to the vehicle. Renal adenosine triphosphate (ATP) levels were reduced by 48% after I/R, whereas SRT1720 restored ATP to 77% of control. Further, SRT1720 reversed the loss of renal mitochondrial mass induced by I/R supported by an increased expression of peroxisome proliferator-activated receptor gamma coactivator 1-alpha and its downstream mediators. SRT1720 also increased ATP levels and mitochondrial mass in human renal HK-2 cells. Moreover, SRT1720 decreased the levels of malondialdehyde, nitrotyrosine, and inducible nitric oxide synthase expression compared to the vehicle. A marked decrease in macrophage infiltration by SRT1720 treatment was associated with a decrease in tumor necrosis factor-α expression and a decrease in IκB-α degradation and nuclear factor-κB phosphorylation after I/R. CONCLUSION: SRT1720 treatment enhanced energy metabolism by stimulating mitochondrial biogenesis as well as decreasing nitrosative stress and inflammation, thereby attenuating I/R-induced renal injury.

Role of PAX-8, CD5, and CD117 in distinguishing thymic carcinoma from poorly differentiated lung carcinoma.

AIM: To determine if PAX-8, CD5, and CD117 can differentiate thymic carcinoma from poorly differentiated lung carcinoma. DESIGN: Archived cases of thymic (n=13) and poorly differentiated lung (n=15) carcinoma were analyzed for intensity and proportion of expression of PAX-8, CD117, and CD5. RESULTS: PAX-8 was positive in 69.2% of thymic and 5.8% of lung carcinomas. CD117 was positive in 84% of thymic and 26.6% of lung carcinomas. A total of 53% of thymic and none of the lung carcinomas were positive for CD5. Forty-six percent, 53%, and 69% of thymic carcinomas were dual positive for combinations of CD5/PAX-8, CD117/CD5, and CD117/PAX-8, respectively. None of the lung carcinomas were dual positive. Positivity for any 2 of the 3 markers was seen in 84% of thymic and none of the lung carcinomas. Triple positivity was seen in 53% of thymic carcinomas. CONCLUSION: Adding PAX-8 to CD117 and CD5 increases the diagnostic yield for thymic carcinoma.

Errors in potassium measurement: a laboratory perspective for the clinician.

Errors in potassium measurement can cause pseudohyperkalemia, where serum potassium is falsely elevated. Usually, these are recognized either by the laboratory or the clinician. However, the same factors that cause pseudohyperkalemia can mask hypokalemia by pushing measured values into the reference interval. These cases require a high-index of suspicion by the clinician as they cannot be easily identified in the laboratory. This article discusses the causes and mechanisms of spuriously elevated potassium, and current recommendations to minimize those factors. "Reverse" pseudohyperkalemia and the role of correction factors are also discussed. Relevant articles were identified by a literature search performed on PubMed using the terms "pseudohyperkalemia," "reverse pseudohyperkalemia," "factitious hyperkalemia," "spurious hyperkalemia," and "masked hypokalemia."