Aberrant nuclear Cdx2 expression in morule-forming tumours in different organs, accompanied by cytoplasmic reactivity

Ovarian endometrioid carcinoma with a sex cord-like pattern: a morphological, immunohistochemical, and molecular analysis

Sex cord-like endometrioid carcinoma (SCLEC) is an uncommon entity which may constitute a diagnostic challenge. This study aimed to perform a clinicopathological, immunohistochemical, and molecular reappraisal of ovarian SCLEC. Consecutive ovarian SCLECs cases from a single institution were reviewed during a 13-year period. Twenty-three immunohistochemical markers were tested; 10 genes were analyzed by next-generation sequencing. Nine cases of ovarian SCLEC were identified. Mean patient age was 65.7 years; three cases showed extraovarian extension. Architectural pattern included sertoliform (n = 2), granulosa-like (n = 2), and mixed granulosa-like/sertoliform (n = 5). Eosinophilic changes accompanied by increased nuclear atypia were observed in four tumors. Endometrioid features (glands, squamous/morular differentiation) were observed in six cases. Most tumors were positive for cytokeratin-7 (8/9), EMA (9/9), estrogen and progesterone receptor (9/9), CD10 (7/9, including a luminal pattern reminiscent of mesonephric neoplasms), nuclear β-catenin (8/9), and CDX2 (8/9). A minority of cases showed block-type p16 pattern (2/9), PAX8-positivity (3/9), and non-diffuse positivity for WT1 (1/9), inhibin (1/9), chromogranin (1/9), and synaptophysin (2/9). All cases were negative for GATA3, TTF1, calretinin, and SF1. Ki67 range was 15-90%. Six cases showed CTNNB1 exon 3 mutation. Eight cases were of "no specific molecular profile" (NSMP) and one was p53-abnormal. In conclusion, SCLECs frequently exhibit a mixed sertoliform/granulosa-like architecture and express epithelial markers, hormone receptors, nuclear β-catenin, and CDX2, with luminal CD10 positivity and CTNNB1 mutations. PAX8 expression is often lost, while other mesonephric, sex cord, and neuroendocrine markers are negative.

The prognostic potential of CDX2 in colorectal cancer: Harmonizing biology and clinical practice

Adjuvant chemotherapy following surgical intervention remains the primary treatment option for patients with localized colorectal cancer (CRC). However, a significant proportion of patients will have an unfavorable outcome after current forms of chemotherapy. While reflecting the increasing complexity of CRC, the clinical application of molecular biomarkers provides information that can be utilized to guide therapeutic strategies. Among these, caudal-related homeobox transcription factor 2 (CDX2) emerges as a biomarker of both prognosis and relapse after therapy. CDX2 is a key transcription factor that controls intestinal fate. Although rarely mutated in CRC, loss of CDX2 expression has been reported mostly in right-sided, microsatellite-unstable tumors and is associated with aggressive carcinomas. The pathological assessment of CDX2 by immunohistochemistry can thus identify patients with high-risk CRC, but the evaluation of CDX2 expression remains challenging in a substantial proportion of patients. In this review, we discuss the roles of CDX2 in homeostasis and CRC and the alterations that lead to protein expression loss. Furthermore, we review the clinical significance of CDX2 assessment, with a particular focus on its current use as a biomarker for pathological evaluation and clinical decision-making. Finally, we attempt to clarify the molecular implications of CDX2 deficiency, ultimately providing insights for a more precise evaluation of CDX2 protein expression.

Pancreatoblastoma in Elderly Adults: Report of Two Patients

Introduction. Pancreatoblastoma is a rare malignant epithelial neoplasm of the pancreas, which often shows multiple lines of differentiation, but is defined by neoplastic cells with acinar differentiation and characteristic squamoid nests. Pediatric patients are most commonly affected, and although a subset is known to occur in adults, the diagnosis is rarely considered in elderly adults. Methods. The clinicopathologic features of two cases of pancreatoblastoma in elderly patients were examined. Results. Two patients (age 80 and 81 years) presented with pancreatoblastoma, including one with early-stage pancreatic disease and one with liver metastasis. Biopsies and one pancreatic resection specimen showed characteristic histomorphologic features, including prominent acinar differentiation and abundant squamoid nests. Both cases had complete loss of SMAD4 (DPC4) immunolabeling. Next generation sequencing was performed on one case and revealed copy number loss of chromosome 11p and 9p21 (CDKN2A/B) and pathogenic or likely pathogenic variants in APC, SMAD4, and PIK3CA. The APC and SMAD4 variants occurred at allele frequencies suggestive of germline mutations, raising the possibility that this patient may have an inherited cancer predisposition syndrome. Conclusions. We present two cases which extend the upper age limit for reported pancreatoblastoma, including one with genetic findings suggestive of an inherited cancer predisposition syndrome.

Clinicopathological, Radiological, and Molecular Features of Primary Lung Adenocarcinoma with Morule-Like Components

BACKGROUND

Morule-like component (MLC) was a rare structure in primary lung adenocarcinoma. We aimed to reveal the clinicopathological, radiological, immunohistochemical, and molecular features of lung adenocarcinoma with MLCs.

METHODS

Twenty lung adenocarcinomas with MLCs were collected, and computed tomographic and histological documents were reviewed. Immunohistochemistry, targeted next-generation sequencing, and Sanger sequencing for β-catenin gene were performed.

RESULTS

There were 9 lepidic adenocarcinomas, 8 acinar adenocarcinomas, 2 papillary adenocarcinomas, and 1 minimally invasive adenocarcinoma. Most patients (16/17) were shown a pure solid nodule, and 1 patient was shown a partly solid nodule on chest computed tomography (CT). Nine cases were accompanied with micropapillary components, and 3 were with cribriform components in which 2 suffered a worse prognosis. No significant association was found between the MCLs and the overall survival of lung adenocarcinoma (P = 0.109). The MLCs were often arranged in whorled or streaming patterns. The cells in MLCs showed syncytial and mild appearance. The MLCs were positive for E-cadherin, CK7, TTF-1, napsin-A, vimentin, and β-catenin (membrane), and negative for CK5/6, p40, p63, Synaptophysin, chromogranin A, and Cdx-2. EGFR mutation, ALK-EML4 fusion, HER2 amplification, and PIK3CA mutation were detected in 16 cases, 2 cases, 1 case, and 1 case, respectively. EGFR mutation was more frequent in adenocarcinomas with MLCs than those without MLCs (P = 0.040). β-catenin gene mutation was not detected in any patients.

CONCLUSIONS

MLC is often observed in the background of acinar, lepidic, and papillary adenocarcinomas. Lung adenocarcinomas with MLCs tend to appear as a solid mass on CT and harbor EGFR gene mutations. The micropapillary components and cribriform components may cause poor prognosis of lung adenocarcinomas with MLCs. Vimentin is always positive in MLCs, and it is a useful marker for the identification of MLCs.

Primary lung adenocarcinoma with morule-like components: a unique histologic hallmark of aggressive behavior and EGFR mutation

BACKGROUND

Lung adenocarcinoma with morule-like components is an unusual variant of lung adenocarcinoma, comprising uniform, tightly packed spindle-shaped cells, which fill the lumen of the glandular structures of the carcinoma. The aim of the study was to outline the clinicopathologic features of this variant.

PATIENTS AND METHODS

We examined a series of 904 surgically resected adenocarcinomas. We defined morule-like components as small buds of spindle-cell proliferation in the tumor lumen of the glandular structures of the carcinoma and calculated their proportion of total tumor mass. Targeted genotyping was performed for KRAS, EGFR, HER2, and BRAF. ALK rearrangements were analyzed immunohistochemically. Immunopositive cases were confirmed using RT-PCR and/or FISH.

RESULTS

We detected 17 cases of adenocarcinoma with morule-like components. This variant, representing only 1.9% was associated with unfavorable outcomes and a mutation in the EGFR. Histologic examination revealed adenocarcinoma with morule-like components accounting for 5-50% of tumors. Among the morule-like components, 10 (58.8%) of the 17 samples showed intracytoplasmic lumina formation containing eosinophilic mucinous material. The presence of micropapillary components in adenocarcinoma with morule-like components suggests that morule-like components could be merely excessive growth of the micropapillary pattern. However, our results indicated no statistical differences in the MIB-1 indices of the morule-like components and the adjacent tumor components or the micropapillary components. The univariate and multivariate analyses revealed a correlation between the presence of a morule-like components and an unfavorable outcome.

CONCLUSIONS

Our study clearly indicated that adenocarcinoma with morule-like components is distinct unfavorable prognostic and predictor for EGFR mutation.

Characterization of azoxymethane-induced colon tumor metastasis to lung in a mouse model relevant to human sporadic colorectal cancer and evaluation of grape seed extract efficacy

The second leading cause of cancer-related deaths (both genders combined) in the United States is colorectal cancer (CRC). This emphasizes the need to develop both effective therapies for CRC patients and pre-clinical models mimicking human disease that carry translational potential in drug-development. Notably, at present there are no in situ models of CRC metastasis to lung. In our azoxymethane-induced colon tumorigenesis study in A/J mice assessing grape seed extract (GSE) efficacy, during necropsy we also found multiple lung nodules suggestive of colon tumor metastasis to lung that were significantly inhibited in GSE fed group. Both histopathological and molecular studies were performed to characterize and establish the origin of these lesions in lung. Histologically these nodules were determined as adenocarcinoma of mucin origin. Molecular analyses by immunohistochemistry (IHC) and RT-PCR revealed strong protein and transcript levels of colon specific markers CDX2 and CK20 in these lung nodules compared to uninvolved control lung tissue. Vis-à-vis, these nodules also showed minimally expressed lung specific biomarkers, specifically surfactant D and TTF-1, in IHC analysis. Additionally, 0.25% GSE supplementation in diet (w/w) decreased the incidence of these lung nodules by 53% and their total number by 66%. Together, the characterization of this unique in situ mouse model of CRC metastasis to lung provides translational opportunities in developing effective therapies to clinically manage and treat CRC at the advanced stage. Moreover, GSE efficacy in inhibiting CRC metastasis to lung in this model further supports its translational potential in controlling CRC growth, progression and metastasis in patients.

CDX2 expression in columnar cell variant of papillary thyroid carcinoma

The columnar cell variant of papillary thyroid carcinoma (CCV-PTC) is a rare subtype of PTC that exhibits morphologic features often described as reminiscent of secretory endometrium or colonic adenomas/adenocarcinomas. CDX2, a nuclear transcription factor, is important for intestinal development. It is normally expressed in intestinal epithelium and is also detected in adenoma and adenocarcinomas of the gastrointestinal tract; however, it has also been reported in tumors of other sites with intestinal-type morphologic features. We evaluated CDX2 expression in CCV-PTC and in a thyroid tissue microarray composed of various benign and malignant thyroid lesions. CDX2 expression was identified in 6 (55%) of 11 cases of CCV-PTC, but not in any other benign and malignant thyroid lesions. We conclude that CDX2 is selectively expressed in CCV-PTC and can be used in distinguishing it from other variants of PTC with overlapping morphologic features.