Poorly Cohesive Carcinoma of the Nonampullary Small Intestine: A Distinct Histologic Subtype With Prognostic Significance.

Poorly cohesive carcinomas (PCCs) are neoplasms characterized by a dyshesive cell invasion pattern featuring single-cell or cord-like stromal infiltration. Although they have been extensively studied in the stomach and other digestive system organs, limited data regarding nonampullary small bowel poorly cohesive carcinomas (SB-PCCs) are hitherto available. The aims of our study were to analyze the clinicopathologic and immunophenotypical features of SB-PCCs (PCC pattern accounting for >50% of the neoplasm) and to compare them with small bowel adenocarcinomas (SBAs), not otherwise specified (SBAs-NOS) and with cancers with a histologically distinct PCC component accounting for 10% to 50% of the neoplasm (mixed-poorly-cohesive-glandular-SBAs). Fifteen SB-PCCs were identified and compared with 95 SBAs-NOS and 27 mixed-poorly-cohesive-glandular-SBAs. Most SB-PCCs (67%) were composed of <10% of signet-ring cells, and all but 1 SB-PCCs exhibited loss of membranous expression of E-cadherin. Compared with SBAs-NOS, SB-PCCs showed a significantly younger patient age at diagnosis, and a stronger association with Crohn disease, and both SB-PCCs and mixed-poorly-cohesive-glandular-SBAs featured a higher rate of lymphovascular and perineural invasion and a lower percentage of mismatch repair-deficient cases. Importantly, the cancer-specific survival of SB-PCC (hazard ratio: 3.81; 95% confidence interval: 1.90-7.64; P<0.001) and mixed-poorly-cohesive-glandular-SBA (4.12; 2.20-7.71; P<0.001) patients was significantly worse compared with SBAs-NOS cases. This study provides objective evidence to the World Health Organization (WHO) 2019 introduction of SB-PCC as a distinctive subtype of nonampullary SBA, by virtue of its unique clinical and histologic features, and suggests that both SB-PCCs and mixed-poorly-cohesive-glandular-SBAs should be separated from SBAs-NOS.

An atypical presentation of Paget's Disease of the breast without nipple involvement: Case report and review of the literature.

We present a case of a 63 year-old Caucasian female who developed a right breast skin lesion discrete from the nipple that was subsequently diagnosed as Paget's Disease of the breast (PDB). Imaging did not reveal an underlying breast cancer or involvement of the nipple. The patient underwent a segmental mastectomy preserving the nipple and final pathology demonstrated residual Paget's disease of the skin and did not reveal any additional underlying breast carcinoma. To our knowledge, this case represents the first reported diagnosed case of isolated PDB without nipple involvement.

Loss of trimethylation at lysine 27 of histone H3 is a predictor of poor outcome in breast, ovarian, and pancreatic cancers.

Methylation of lysine 27 on histone H3 (H3K27) by the EZH2 complex is an epigenetic mark that mediates gene silencing. EZH2 is overexpressed in many cancers and correlates with poor prognosis in both breast and prostate cancers. However, the status of H3K27 methylation and its clinical implication in cancer patients have not been reported. We thus examined trimethylation of H3K27 (H3K27me3) by immunohistochemistry and its association with clinical variables and prognosis in breast, ovarian, and pancreatic cancers. We found that H3K27me3 expression was significantly lower in breast, ovarian and pancreatic cancers than in normal tissues (62% in breast cancer vs. 88% in normal breast tissue, P = 0.001; 38.4% in ovarian cancer vs. 83.3% in normal ovarian tissue, P < 0.05; and 26% in pancreatic cancer vs. 89% in normal pancreatic tissue, P < 0.001). H3K27me3 expression showed significant prognostic impact in breast, ovarian and pancreatic cancers in univariate survival analyses. In all three cancer types, patients with low expression of H3K27me3 had significantly shorter overall survival time when compared with those with high H3K27me3 expression. In a multivariate model, H3K27me3 expression was an independent prognostic value for overall survival in all three cancer types. These results suggest that H3K27me3 expression is a prognostic indicator for clinical outcome in patients with breast, ovarian, and pancreatic cancers.

Antitumor activity of epidermal growth factor receptor-related protein is mediated by inactivation of ErbB receptors and nuclear factor-kappaB in pancreatic cancer.

The erbB family of receptor tyrosine kinases plays critical roles in human cancers, including pancreatic cancer. Discovering a specific agent, which targets multiple members of the erbB family, would be important in pancreatic cancer therapy. Recently, we isolated a novel negative regulator of epidermal growth factor receptor (EGFR), termed EGFR-related protein (ERRP), whose expression attenuates EGFR activation. In the current study, we examined the effects of recombinant ERRP on the growth and ligand-induced activation of multiple members of erbB family in three pancreatic cancer cell lines that express varying levels of EGFR and other member(s) of its family, specifically HER-2. Additionally, we compared the growth inhibitory effect of ERRP with that of Erbitux or Herceptin. Our results showed that ERRP is most effective in inhibiting proliferation of BxPC-3, HPAC, and PANC-1 pancreatic cancer cells. ERRP also inhibited ligand-induced activation of EGFR, HER-2, and HER-3 (ErbB3). In contrast, Erbitux and Herceptin only partially or modestly inhibited activation of EGFR, HER-2, and HER-3. Most importantly, ERRP was found to inhibit pancreatic tumor growth in a severe combined immunodeficient mouse xenograft model. The antitumor activity of ERRP correlates well with tumor differentiation and down-regulation of nuclear factor-kappaB activity. In summary, our results suggest that ERRP is an effective pan-erbB inhibitor, which could be a potential therapeutic agent for pancreatic cancers expressing different levels and subclasses of erbB family of proteins.

Invasive micropapillary carcinomas of the ampullo-pancreatobiliary region and their association with tumor-infiltrating neutrophils.

Invasive micropapillary carcinoma, originally described as a distinctive type of invasive carcinoma in the breast, is being increasingly recognized as a separate entity in many other organs; however, it has not yet been documented in the pancreas or periampullary region. In this study, 313 pancreatic and 73 periampullary carcinomas were reviewed to investigate the micropapillary pattern in this location. Eight periampullary and eight pancreatic cases (4%) were composed at least focally (>20%) of invasive micropapillary carcinoma. The patients were 10 males and six females, mean age 69 years. The mean tumor size was 3.2 cm. Lymph node metastasis was detected in 11/15 cases. The median survival was 8 months (all were resected). Invasive micropapillary carcinoma was characterized by small, closely packed micropapillary clusters (without fibrovascular cores) lying within clefts. The cells had moderate degree of nuclear atypia. In nine cases, there was abundant inflammation composed of neutrophils concentrating around the tumor cells, both intraepithelial ('cannibalism') and stromal. Molecules implicated in abnormalities of tumor cell-stroma adhesion, galectin-3 and E-cadherin were expressed in the cytoplasm of 11/11 and 9/11 cases, respectively. Reversal of cell polarity was observed by MUC 1 in all 11 cases tested, which showed labeling in the stroma-facing surfaces of the micropapillary clusters, also confirming that the clefts are not merely a processing artifact, but indeed a true biologic alteration. In conclusion, invasive micropapillary carcinoma constitutes 4% of carcinomas in the pancreatic/periampullary region and is commonly associated with abundant neutrophilic infiltrates. Invasive miropapillary carcinoma appears to be more common in periampullary than in pancreatic invasive micropapillary carcinoma would qualify as poorly differentiated both based on pattern and the median survival (8 months)..