MSH6 immunohistochemical heterogeneity in colorectal cancer: comparative sequencing from different tumor areas.

Mismatch repair protein (MMR) immunohistochemistry is an important tool in screening for Lynch syndrome in colorectal cancer patients. Unusual staining patterns such as heterogeneous MSH6 staining have been reported in colorectal and endometrial cancers. We aim to better understand MSH6 staining heterogeneity in colorectal cancer by comparative sequencing of different tumor areas for MMR and DNA polymerase mutations.

Two-stain immunohistochemical screening for Lynch syndrome in colorectal cancer may fail to detect mismatch repair deficiency.

Universal screening for Lynch syndrome in colorectal cancer is recommended, and immunohistochemistry for the mismatch repair proteins is commonly used. To reduce cost, some screen using only MSH6 and PMS2, with reflex to the partner stain if either are absent (two-stain method). An expression pattern revealing absent MSH2 and intact MSH6 is not expected, but could result in failed Lynch syndrome detection.

Transformation of T-Cell Acute Lymphoblastic Lymphoma to Peripheral T-Cell Lymphoma: A Report of Two Cases.

Nonhepatosplenic/noncutaneous peripheral T-cell lymphoma (NHNC PTCL) represents a miscellaneous group of unrelated T-cell lymphomas of which only isolated cases have been reported. We describe two cases of transformation from T-lymphoblastic leukemia/lymphoma to NHNC PTCL. Transformation into more aggressive disease is a rare event in T-cell lineage-derived hematologic malignancies compared to B-cell neoplasms.

Immunohistochemical Pitfalls: Common Mistakes in the Evaluation of Lynch Syndrome.

At least 15% of colorectal cancers diagnosed in the United States are deficient in mismatch repair mechanisms. Most of these are sporadic, but approximately 3% of colorectal cancers result from germline alterations in mismatch repair genes and represent Lynch syndrome. It is critical to identify patients with Lynch syndrome to institute appropriate screening and surveillance for patients and their families.

Comparing whole slide digital images versus traditional glass slides in the detection of common microscopic features seen in dermatitis.

Background: The quality and limitations of digital slides are not fully known. We aimed to estimate intrapathologist discrepancy in detecting specific microscopic features on glass slides and digital slides created by scanning at ×20.

Methods: Hematoxylin and eosin and periodic acid-Schiff glass slides were digitized using the Mirax Scan (Carl Zeiss Inc.

Colon Cancer Metastatic to the Biliary Tree.

Metastasis of colon adenocarcinoma is commonly found in the lung, liver, or peritoneum. Common bile duct (CBD) tumors related to adenomas from familial adenomatous polyposis metastasizing from outside of the gastrointestinal tract have been reported. We report a case of biliary colic due to metastatic colon adenocarcinoma to the CBD.

Evaluation of PAX8 Expression and Its Potential Diagnostic and Prognostic Value in Renal and Extra-Renal Ewing Sarcomas/PNETs.

PAX8 is a transcription factor involved in the regulation of organogenesis of the thyroid gland, kidney, and Müllerian system. It is commonly expressed in epithelial tumors of thyroid and parathyroid glands, kidney, thymus, and female genital tract. PAX8 is increasingly used in the establishment of tissue of origin in carcinomas and has recently been identified in a subset of small blue round cell tumors including Ewing sarcomas/PNETs.

Bariatric surgery improves histological features of nonalcoholic fatty liver disease and liver fibrosis.

Nonalcoholic fatty liver disease (NAFLD) is prevalent in obese patients. We sought to determine the effects of bariatric surgery on the histological features of NAFLD. Two blinded pathologists graded liver biopsies done during bariatric procedures and subsequent operations in 160 patients using the Brunt classification.