Expression of cytokeratins 7 and 20 in primary carcinomas of the stomach and colorectum and their value in the differential diagnosis of metastatic carcinomas to the ovary

Cutaneous Metastasis of Transverse Colon Cancer with an Aberrant Pattern of CK7/CK20/CDX2 and High Microsatellite Instability

A 79-year-old woman was diagnosed with transverse colon cancer, moderately differentiated adenocarcinoma. She underwent surgery and postoperative adjuvant chemotherapy. At 80 years old, the patient exhibited changes in skin tone at the chest and abdomen with CK7+/CK20-/CDX2- immunostaining that was later identified as poorly differentiated adenocarcinoma. The diagnosis was cancer of unknown primary origin. The patient passed away three months after the detection of the skin lesion. Autopsy revealed recurrence at the transverse colon, multiple organ metastases, a similar postmortem immunostaining pattern, and high-frequency microsatellite instability (MSI-high). We herein report this case of CK7+/CK20-/CDX2- and MSI-high transverse colon cancer showing cutaneous metastasis.

Histopathological Evaluation and Molecular Diagnostic Tests for Peritoneal Metastases with Unknown Primary Site-a Review

Cancer of unknown primary (CUP) is a well-studied entity with guidelines available for the management of patients with CUP. The peritoneum represents one of the metastatic sites in CUP, and peritoneal metastases (PM) could present as CUP. PM of unknown origin remains a poorly studied clinical entity. There is only one series of 15 cases, one population-based study, and few other case reports on this subject. Studies on CUP, in general, cover some common tumour histological types like adenocarcinomas and squamous carcinomas. Some of these tumours may have a good prognosis though majority have high-grade disease with a poor long-term outcome. Some of the histological tumour types commonly seen in the clinical scenario of PM like mucinous carcinoma have not been studied. In this review, we divide PM into five histological types-adenocarcinomas, serous carcinomas, mucinous carcinomas, sarcomas and other rare varieties. We provide algorithms to identify the primary tumour site using immunohistochemistry when imaging, and endoscopy fails to establish the primary tumour site. The role of molecular diagnostic tests for PM or unknown origin is also discussed. Current literature on site-specific systemic therapy based on gene expression profiling does not show a clear benefit of this approach over empirical systemic therapies.

Metastatic Small Bowel Adenocarcinoma Mimicking a Primary Ovarian Mucinous Tumour - Clinical, Radiologic, Pathologic and Molecular Correlation

We describe an interesting case of a patient who presented with a large adnexal mass, first favored to be mucinous carcinoma of the gynecologic origin. The primary tumour site was ascertained after the patient's small bowel was resected by identifying an adenomatous component evolving into an invasive adenocarcinoma identical in morphology and immunophenotype to the ovarian tumour. Notably, both tumours were found to harbor a BRAF K601E mutation, which is extremely rare for a primary of the ovary. BRAF mutations are present in a subset of large bowel and small bowel adenocarcinoma, but our case shows the first instance of a BRAF K601E mutation being present in a small bowel adenocarcinoma, to the best of our knowledge. This case serves as a great illustration of the pivotal role of molecular diagnostics in modern pathology in arriving at the correct diagnosis. Additionally, it is an excellent example of how clinical-radiologic-pathologic-molecular correlation plays into the landscape of molecular pathology to deliver optimal care for the patient.

Loss of SATB2 expression correlates with cytokeratin 7 and PD-L1 tumor cell positivity and aggressiveness in colorectal cancer

Colorectal carcinoma (CRC) is a disease that causes significant morbidity and mortality worldwide. To improve treatment, new biomarkers are needed to allow better patient risk stratification in terms of prognosis. This study aimed to clarify the prognostic significance of colonic-specific transcription factor special AT-rich sequence-binding protein 2 (SATB2), cytoskeletal protein cytokeratin 7 (CK7), and immune checkpoint molecule programmed death-ligand 1 (PD-L1). We analyzed a cohort of 285 patients with surgically treated CRC for quantitative associations among the three markers and five traditional prognostic indicators (i.e., tumor stage, histological grade, variant morphology, laterality, and mismatch-repair/MMR status). The results showed that loss of SATB2 expression had significant negative prognostic implications relative to overall survival (OS) and cancer-specific survival (CSS), significantly shortened 5 years OS and CSS and 10 years CSS in patients with CRC expressing CK7, and borderline insignificantly shortened OS in patients with PD-L1 + CRC. PD-L1 showed a significant negative impact in cases with strong expression (membranous staining in 50-100% of tumor cells). Loss of SATB2 was associated with CK7 expression, advanced tumor stage, mucinous or signet ring cell morphology, high grade, right-sided localization but was borderline insignificant relative to PD-L1 expression. CK7 expression was associated with high grade and SATB2 loss. Additionally, a separate analysis of 248 neoadjuvant therapy-naïve cases was performed with mostly similar results. The loss of SATB2 and CK7 expression were significant negative predictors in the multivariate analysis adjusted for associated parameters and patient age. In summary, loss of SATB2 expression and gain of CK7 and strong PD-L1 expression characterize an aggressive phenotype of CRC.

Roles of Keratins in Intestine

Keratins make up a major portion of epithelial intermediate filament proteins. The widely diverse keratins are found in both the small and large intestines. The human intestine mainly expresses keratins 8, 18, 19, and 20. Many of the common roles of keratins are for the integrity and stability of the epithelial cells. The keratins also protect the cells and tissue from stress and are biomarkers for some diseases in the organs. Although an increasing number of studies have been performed regarding keratins, the roles of keratin in the intestine have not yet been fully understood. This review focuses on discussing the roles of keratins in the intestine. Diverse studies utilizing mouse models and samples from patients with intestinal diseases in the search for the association of keratin in intestinal diseases have been summarized.

Cytokeratin 7 and cytokeratin 20 expression in cancer: A tissue microarray study on 15,424 cancers

Combined analysis of cytokeratin 7 (CK7) and cytokeratin 20 (CK20) is often used for assessing the origin of metastatic cancer. To evaluate the diagnostic utility of CK7 and CK20, tissue microarrays containing 15,424 samples from 120 different tumor types and subtypes and 608 samples of 76 different normal tissue types were analyzed by immunohistochemistry. CK7 positivity was seen in 52% (8.7% weak, 5.9% moderate, 37% strong) and CK20 positivity in 23% (5.1% weak, 3.4% moderate, 15% strong) of interpretable tumors. Of 8390 positive tumors, 1181 (14%) showed positivity for CK7 and CK20, 5380 (64%) showed positivity for CK7 alone, and 1829 (22%) showed positivity for CK20 alone. CK20 predominated in gastrointestinal tract, urothelial and Merkel cell carcinomas. CK7 was usually negative in prostate cancer and colorectal cancer. Combined evaluation of CK7/CK20 revealed the best diagnostic utility in CK20 positive tumors, where CK7 negativity is often linked to colorectal origin while CK7 positivity argues for urothelial origin or mucinous ovarian cancer. Associations with unfavorable tumor features were found for cytokeratin 7 loss in breast cancer of no special type, urothelial and renal cell carcinomas, for CK7 overexpression in high-grade serous ovarian and gastric cancer, and for CK20 overexpression in urothelial carcinoma. CK20 loss was linked to MSI in gastric (p = 0.0291) and colorectal adenocarcinoma (p < 0.0001). These analyses provide comprehensive data on the frequency of CK7 and CK20 immunostaining - alone or in combination - in human cancers. These data facilitate interpretation of CK7/CK20 immunostaining in cancers.

Synchronous "skip" facial metastases from colorectal adenocarcinoma: a case report and review of literature

Background

Skin metastases from colorectal adenocarcinoma are rare conditions that are metachronous in most of cases and may represent the first sign of a recurrence. These lesions are usually located to the abdominal wall on postoperative scars, perineum and chest due to direct spread from the tumor or to the lymphatic and venous dissemination. We describe a rare case of synchronous skin metastases in a patient affected by sigmoid adenocarcinoma with no sign of liver and lung repetitive lesions.

Case presentation

We admitted a 59 years old male, with no relevant medical history. He was evaluated by our tertiary center of colorectal surgery complaining diarrhoea and abdominal pain. The physical examination revealed a palpable mass in left flank of the abdomen. The colonoscopy showed a sub-stenosis of the sigmoid colon (G2 adenocarcinoma). No repetitive lesions were detected by the preoperative CT scan. The patient reported a rapid grow of a soft supralabial and chin nodules in the last 2 months, which he believed to be related to the use of the mask due to COVID-19 pandemic. A laparoscopic left hemicolectomy with complete mesocolic excision and a local excision of both facial nodules were performed. The histological examination revealed a poorly differentiated signet ring cell colorectal adenocarcinoma with metastases in seven pericolic lymphonodes. The excisional biopsy of the skin nodules revealed a subcutaneous metastases from primary colorectal tumour.

Conclusions

As far as we know, synchronous facial metastases from colorectal cancer in the absence of any other metastases has never been described before. The onset of new skin nodules in patients affected by colorectal cancer should raise-up the clinical suspicion of metastatic lesions even when repetitive lesions are not detected in the liver or lungs.

Novel Diagnostic Biomarkers in Colorectal Cancer

Colorectal cancer (CRC) is still a leading cause of cancer death worldwide. Less than half of cases are diagnosed when the cancer is locally advanced. CRC is a heterogenous disease associated with a number of genetic or somatic mutations. Diagnostic markers are used for risk stratification and early detection, which might prolong overall survival. Nowadays, the widespread use of semi-invasive endoscopic methods and feacal blood tests characterised by suboptimal accuracy of diagnostic results has led to the detection of cases at later stages. New molecular noninvasive tests based on the detection of CRC alterations seem to be more sensitive and specific then the current methods. Therefore, research aiming at identifying molecular markers, such as DNA, RNA and proteins, would improve survival rates and contribute to the development of personalized medicine. The identification of “ideal” diagnostic biomarkers, having high sensitivity and specificity, being safe, cheap and easy to measure, remains a challenge. The purpose of this review is to discuss recent advances in novel diagnostic biomarkers for tumor tissue, blood and stool samples in CRC patients.

Cytokeratin 7 expression as a predictor of an unfavorable prognosis in colorectal carcinoma

Colorectal carcinoma (CRC) is associated with significant morbidity and mortality worldwide. Cytokeratins (CKs) are widely expressed in various types of carcinomas, whereas in CRC it is usually CK7 − and CK20 + . A subset of CRCs is CK7 + . This study aims to determine the prevalence of CK7 expression in CRC and its impact on overall survival. We analyzed 300 randomly selected surgically treated CRC cases using paraffin embedded tumor tissue samples and evaluated CK7 and CK20 expression using the tissue microarray method. Tumors with positivity > 10% and > 25% of tumor cells were considered CK7 and CK20 positive, respectively. Expression of both CKs and several clinical-pathological variables (stage, grade, laterality, mismatch-repair/MMR status) were evaluated using patient follow up data (Kaplan–Meier analysis of cancer-specific survival (CSS)). Significant results include shorter CSS (restricted mean 4.98 vs. 7.74 years, P = 0.007) and 5-year survival (29.4% vs. 64.6%, P = 0.0221) in CK7 + tumors compared to CK7 − tumors, respectively; without significant association with grade, stage or right-sided location. These results were significant in a multivariate analysis. CK20 + tumors are more frequently MMR-proficient and left-sided. MMR-deficient tumors are more frequently right-sided and had longer survival. CK7 expression, right-sided location (rmean CSS 6.83 vs. 8.0 years, P = 0.043), MMR-proficiency (rmean CSS 7.41 vs. 9.32 years, P = 0.012), and UICC stages III + IV (rmean CSS 6.03 vs. 8.92 years, P < 0.001) of the tumor correlated with negative prognostic outcomes, whereas the most significant results concern stage and CK7 positivity. The result concerning negative prognostic role of CK7 differs from those obtained by several previous studies focused on this topic.

Modelling hereditary diffuse gastric cancer initiation using transgenic mouse-derived gastric organoids and single-cell sequencing

Hereditary diffuse gastric cancer (HDGC) is a cancer syndrome caused by germline variants in CDH1, the gene encoding the cell-cell adhesion molecule E-cadherin. Loss of E-cadherin in cancer is associated with cellular dedifferentiation and poor prognosis, but the mechanisms through which CDH1 loss initiates HDGC are not known. Using single-cell RNA sequencing, we explored the transcriptional landscape of a murine organoid model of HDGC to characterize the impact of CDH1 loss in early tumourigenesis. Progenitor populations of stratified squamous and simple columnar epithelium, characteristic of the mouse stomach, showed lineage-specific transcriptional programs. Cdh1 inactivation resulted in shifts along the squamous differentiation trajectory associated with aberrant expression of genes central to gastrointestinal epithelial differentiation. Cytokeratin 7 (CK7), encoded by the differentiation-dependent gene Krt7, was a specific marker for early neoplastic lesions in CDH1 carriers. Our findings suggest that deregulation of developmental transcriptional programs may precede malignancy in HDGC. © 2021 The Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

Detection and analysis of multiple biomarkers in ovarian cancer: clinical significance in diagnosis, treatment, and prognosis evaluation

BACKGROUND

The purpose of this study was to explore the clinical significance of CA125, CK7, CK20, ER, PR, C-erbb2, and P-gp in ovarian cancer.

METHODS

Ovarian cancer patients were recruited from Nantong Cancer Hospital between March 2006 and July 2011. The expressions of CA125, CK7, CK20, ER, PR, C-erbb2, and P-gp were determined by immunohistochemistry (IHC).The chi-square test (χ2) was used to analyze the correlation between each index and the clinical characteristics of the patients. The patients were followed up to record the cancer recurrence time. The Kaplan-Meier method was used to map the cumulative recurrence-free survival (RFS) rate, and COX regression analysis was established for multivariate analysis.

RESULTS

The results of IHC showed that the positive expression rates of CA125, CK7, ER, C-erbb2, and P-gp in malignant ovarian cancer tissues were significantly higher than those in benign ovarian cancer tissues. CA125 expression in malignant ovarian cancer was significantly correlated with the age of patients and the Federation of International Gynecology and Obstetrics (FIGO) stage. CK7 expression in malignant ovarian cancer was significantly correlated with the age, tissue differentiation, and number of residual lesions. CK20 expression in malignant ovarian cancer was significantly correlated with the age and tissue differentiation of the patients. ER expression in malignant ovarian cancer was significantly correlated with the age of patients and FIGO stage. PR expression in malignant ovarian cancer was significantly correlated with the age of the patients. C-erbb2 expression in malignant ovarian cancer was significantly correlated with the age of the patients. P-gp expression in malignant ovarian cancer was significantly correlated with the patient age, pathological type, and tissue differentiation. The expression of CA125, CK7, CK20, C-erbb2, and P-gp had significant effects on the prognosis of patients with ovarian cancer. The COX regression analysis showed that P-gp was an independent risk factor for ovarian cancer.

CONCLUSIONS

In malignant ovarian cancer tissues, CA125, CK7, CK20, ER, PR, C-erbb2, and P-gp are over-expressed. The expression of P-gp is an independent risk factor for ovarian cancer, and it can be an important target for the treatment of malignant ovarian cancer.

Keratin intermediate filaments in the colon: guardians of epithelial homeostasis

Keratin intermediate filament proteins are major cytoskeletal components of the mammalian simple layered columnar epithelium in the gastrointestinal tract. Human colon crypt epithelial cells express keratins 18, 19 and 20 as the major type I keratins, and keratin 8 as the type II keratin. Keratin expression patterns vary between species, and mouse colonocytes express keratin 7 as a second type II keratin. Colonic keratin patterns change during cell differentiation, such that K20 increases in the more differentiated crypt cells closer to the central lumen. Keratins provide a structural and mechanical scaffold to support cellular stability, integrity and stress protection in this rapidly regenerating tissue. They participate in central colonocyte processes including barrier function, ion transport, differentiation, proliferation and inflammatory signaling. The cell-specific keratin compositions in different epithelial tissues has allowed for the utilization of keratin-based diagnostic methods. Since the keratin expression pattern in tumors often resembles that in the primary tissue, it can be used to recognize metastases of colonic origin. This review focuses on recent findings on the biological functions of mammalian colon epithelial keratins obtained from pivotal in vivo models. We also discuss the diagnostic value of keratins in chronic colonic disease and known keratin alterations in colon pathologies. This review describes the biochemical properties of keratins and their molecular actions in colonic epithelial cells and highlights diagnostic data in colorectal cancer and inflammatory bowel disease patients, which may facilitate the recognition of disease subtypes and the establishment of personal therapies in the future.

Krukenberg Tumors: Update on Imaging and Clinical Features

OBJECTIVE. The purpose of this case-based article is to discuss the pathophysiologic findings, common pathways of spread, and imaging features associated with Krukenberg tumors. CONCLUSION. Not all ovarian metastases are Krukenberg tumors. Krukenberg tumors are the most common subtype of ovarian metastases, and they are histologically characterized by signet ring cell mucinous features. Common primary tumor sites include the stomach or colon. Although often difficult, distinguishing between Krukenberg tumors and primary ovarian malignancy on imaging is important because of management and prognostic implications.

Metachronous Ovarian Metastases in a Patient with Primary Colorectal Cancer. A Case Report and Review of the Literature

BACKGROUND Metachronous ovarian metastasis from primary colorectal cancer (CRC) is a rare condition that is diagnosed after the treatment of CRC. In most cases, ovarian metastases present without specific symptoms or signs and are usually diagnosed during follow-up imaging. A rare case is presented of metachronous ovarian metastasis from primary CRC, diagnosed on follow-up by computed tomography (CT) and magnetic resonance imaging (MRI), and includes a review of the literature. CASE REPORT A 66-year-old woman recently underwent a left hemicolectomy for a stage T3, N0, M0 primary adenocarcinoma of the sigmoid colon, which was completely excised. Three years later, follow-up CT and MRI imaging showed a right ovarian cyst. She underwent exploratory laparotomy and bilateral salpingo-oophorectomy, which identified tumor in the right ovary. Histopathology and immunohistochemistry confirmed metachronous ovarian metastasis from CRC. The patient was referred for further treatment. CONCLUSIONS Newly-diagnosed ovarian metastasis from primary colorectal cancer (CRC) is challenging to diagnose and manage, and may initially be incorrectly diagnosed as malignancy of primary ovarian origin. This case demonstrated that it is important to confirm the diagnosis with imaging, histology, and the appropriate use of tumor markers. Because ovarian metastases do not respond favorably to chemotherapy, the treatment of choice is surgery. However, for women who are treated for CRC, the use of prophylactic oophorectomy remains controversial.

Establishment and characterization of a novel cell line (cc‑006cpm8) of moderately/poorly differentiated colorectal adenocarcinoma derived from a primary tumor of a patient

In the present study, the cc‑006cpm8 novel colon cell line was established from a sample of right colorectal adenocarcinoma obtained from a woman with liver metastasis. It was possible to culture this cell line for ≥100 passages in vitro with vigorous growth. Morphologically, the cells grew as several layers with tight adhesion to the surface of the culture plate. The morphological, immunological and ultrastructural features of these cells suggested their epithelial origin. The characterization of this cell line indicated a doubling time of 27 h, a colony forming efficiency of 73.2% in semisolid media and a plate efficiency of 66.5% in liquid culture. The modal number of chromosomes was 50. In vivo, the cc‑006cpm8 cells underwent tumorigenesis in all nude mice used. Immunohistochemical analysis demonstrated that mutS homolog 2 (MSH2) and MSH6 were expressed; however, mutL homolog 1 and postmeiotic segregation 2 were downregulated in cc‑006cpm8 cells. To determine the mutation profile of the cell line analyzed, exome capture DNA sequencing was performed. The results revealed 20 hypermutated exons comprising single nucleotide polymorphisms, and insertion and deletions (InDels), including single nucleotide variants of mucin (MUC)19, MUC16, MUC12, filaggrin and AHNAK nucleoprotein 2, and InDels of β defensin‑126, microRNA‑3665, WNK lysine deficient protein kinase 1 and SLAIN motif‑containing protein 1. In addition, commonly mutated genes in colorectal cancer and exon mutations of genes in cc‑006cpm8 cells were analyzed, including adenomatous polyposis coli, tumor protein p53, Drosophila mothers against decapentaplegic 4, phosphatidylinositol‑4,5‑bisphosphate 3‑kinase catalytic subunit α and Kirsten rat sarcoma, and genes associated with the DNA mismatch repair pathway were investigated.

[Culture and identification of tumor stem cells from surgically resected colorectal cancer tissues]

OBJECTIVE

To obtain cancer stem cells (CSCs) from surgically resected colorectal cancer specimens and identify their stem cell characteristics.

METHODS

Colorectal cancer tissue specimen obtained from a patient undergoing radical resection of colorectal cancer were implanted in nude mice, and the xenograft was harvested 1 month later to obtain purified tumor cells by enzyme digestion and adherent culture. The CSCs were screened by limiting dilution method and serum-free culture to identify their phenotypes. Soft agar colony assay was used to assess the proliferative ability of the CSCs and human colorectal cancer cell line SW480. The tumorigenic ability of the isolated CSCs and SW480 cells was evaluated by observing their subcutaneous tumor formation in nude mice. Western blotting and immunofluorescence assay were used to detect the immunophenotype of the CSCs and SW480 cells.

RESULTS

The primary cultured CSCs from clinical specimens of colorectal cancer underwent differentiation in the presence of serum in the culture. Soft agar colony formation assay showed that the CSCs had a colony formation rate above 50%, significantly higher than the rate of colorectal cancer SW480 cells (4.41%; P < 0.01). In nude mice, subcutaneous injection of 500 CSCs was sufficient to result in subcutaneous tumor formation, while the injection of 500 SW480 cells failed to form any subcutaneous tumors. The CSCs expressed CD133 and CD44 but not CK7, while SW480 cells expressed CK7 but not CD133 or CD44.

CONCLUSIONS

CSCs can be derived by primary culture of cancer cells obtained from surgically resected colorectal cancer tissue followed by serum-free culture, and the CSCs obtained have self-renewal and differentiation abilities.

Pathologic differential diagnosis of metastatic carcinoma in the liver

The liver is one of the most common sites to which malignancies preferentially metastasize. Although a substantial number of liver malignancies are primary tumors, including hepatocellular carcinoma and intrahepatic cholangiocarcinoma, the metastasis of carcinomas to the liver is relatively common and frequently encountered in clinical settings. Representative carcinomas that frequently metastasize to the liver include colorectal carcinoma, breast carcinoma, neuroendocrine tumors, lung carcinoma, and gastric carcinoma. The diagnostic confirmation of suspected metastatic lesions in the liver is generally achieved through a histopathologic examination of biopsy tissues. Although morphology is the most important feature for a pathologic differential diagnosis of metastatic carcinomas, immunohistochemical studies facilitate the differentiation of metastatic carcinoma origins and subtypes. Useful immunohistochemical markers for the differential diagnosis of metastatic carcinomas in the liver include cytokeratins (CK7, CK19, and CK20), neuroendocrine markers (CD56, synaptophysin, and chromogranin A), and tissue-specific markers (CDX2, SATB2, TTF-1, GCDFP-15, mammaglobin, etc.). Here, we provide a brief review about the pathologic differential diagnosis of major metastatic carcinomas in the liver.

Diagnostic Utility of SATB2 in Metastatic Krukenberg Tumors of the Ovary: An Immunohistochemical Study of 70 Cases With Comparison to CDX2, CK7, CK20, Chromogranin, and Synaptophysin

SATB2 is a sensitive marker for colorectal adenocarcinomas. No study has investigated its diagnostic utility in metastatic Krukenberg tumors (MKTs) of the ovary. Here we performed immunohistochemical staining SATB2 in 70 MKTs of various origins (stomach 27, colorectum 13, appendix 20 including 19 metastatic adenocarcinomas ex goblet cell carcinoids [AdexGCC] and 1 conventional poorly differentiated carcinoma with signet ring cells, breast 5, bladder 3, lung 2) to assess its diagnostic utility. We also compared SATB2 with CDX2, CK7, CK20, chromogranin, and synaptophysin in MKTs of gastric origin (MKTs-stomach), those of colorectal origin (MKTs-colorectum) and those due to appendiceal AdexGCCs (MKT-AdexGCCs) for their sensitivity and specificity to distinguish these tumors. SATB2 staining was seen in 1/27 (4%) MKTs-stomach (40% cells), 7/13 (54%) MKTs-colorectum (mean: 17% cells, median: 7%, range: 2% to 60%), and 19/19 (100%) of MKT-AdexGCCs (mean: 97% cells, median: 100%, range: 80% to 100%) (P<0.01 between any two). SATB2 staining was seen in 1/1 metastatic appendiceal poorly differentiated carcinoma with signet ring cells (5% cells), 1/3 MKTs of bladder origin (60% cells), 0/2 MKTs of pulmonary origin, and 1/5 MKTs of breast origin (10% cells). SATB2 staining was diffuse strong in MKT-AdexGCCs whereas in other MKTs it was focal and weak in the signet ring and nonsignet ring nonglandular cells and from focal weak to diffuse strong in well-formed glands. MKTs-stomach, MKTs-colorectum, and MKT-AdexGCCs showed no significant staining difference in CDX2 (100%, 100%, 100% cases, respectively; P=1.0), CK20 (96%, 100%, 100%, respectively; P=1.0), chromogranin (59%, 31%, 63%, respectively; P>0.05) or synaptophysin (59%, 63%, 84%, respectively; P>0.05) but they had significant difference in CK7 staining (93%, 8%, 42%, respectively; P<0.05). Among these 6 markers, SATB2 is the best one to distinguish MKT-AdexGCCs from MKTs-stomach (100% sensitivity, 96% specificity) and MKTs-colorectum (100% sensitivity and 100% specificity if staining more than 75% tumor cells as the cutoff). In distinguishing MKTs-stomach from MKTs-colorectum, SATB2 is not as good as CK7 which is the best marker. Our results indicate that SATB2 is a highly sensitive marker (100% sensitivity) for metastatic MKT-AdexGCCs with high specificity (100% specificity when showing strong staining in at least 75% cells) among MKTs. SATB2 is a useful marker for determining the primary sites of MKTs of the ovary.

Cutaneous Metastases: A Review and Diagnostic Approach to Tumors of Unknown Origin

CONTEXT.—

Cutaneous metastases from a distant malignancy are a diagnostic challenge for pathologists. Secondary involvement of the skin by a metastatic process portends a much worse clinical prognosis than any primary cutaneous malignant mimickers. Immunohistochemical staining methods continue to evolve and are of paramount importance in diagnosis.

OBJECTIVE.—

To review the clinical, histopathologic, and immunohistochemical staining patterns for commonly encountered entities and discuss potential pitfalls in diagnosis. A practical guide useful in approaching cutaneous metastases of unknown primary is outlined.

DATA SOURCES.—

An extensive search and review of literature in PubMed was performed, processed, and condensed.

CONCLUSIONS.—

Cutaneous metastases have broad histopathologic patterns. They are nearly always dermal based, with an overall foreign appearance. They can be single papules/nodules or multiple in number, mimicking an inflammatory or infectious process. Ultimately, immunohistochemistry remains an essential diagnostic tool, and clinical correlation is paramount in the workup of these entities.

Subclassification and Detection of New Markers for the Discrimination of Primary Liver Tumors by Gene Expression Analysis Using Oligonucleotide Arrays

Background/Aims

The failure to correctly differentiate between intrahepatic cholangiocarcinoma (CC) and hepatocellular carcinoma (HCC) is a significant clinical problem, particularly in terms of the different treatment goals for both cancers. In this study a specific gene expression profile to discriminate these two subgroups of liver cancer was established and potential diagnostic markers for clinical use were analyzed.

Methods

To evaluate the gene expression profiles of HCC and intrahepatic CC, Oligonucleotide arrays (AffymetrixU133A) were used. Overexpressed genes were checked for their potential use as new markers for discrimination and their expression values were validated by reverse transcription polymerase chain reaction and immunohistochemistry analyses.

Results

695 genes/expressed sequence tags (ESTs) in HCC (245 up-/450 down-regulated) and 552 genes/ESTs in CC (221 up-/331 down-regulated) were significantly dysregulated (p＜0.05, fold change >2, ≥70%). Using a supervised learning method, and one-way analysis of variance a specific 270-gene expression profile that enabled rapid, reproducible differentiation between both tumors and nonmalignant liver tissues was established. A panel of 12 genes (e.g., HSP90β, ERG1, GPC3, TKT, ACLY, and NME1 for HCC; SPT2, T4S3, CNX43, TTD1, HBD01 for CC) were detected and partly described for the first time as potential discrimination markers.

Conclusions

A specific gene expression profile for discrimination of primary liver cancer was identified and potential marker genes with feasible clinical impact were described.

Diagnostic algorithm for determining primary tumor sites using peritoneal fluid

This study was conducted to develop a novel algorithm for determining the origin of tumors by combining analysis of cluster patterns with immunocytochemistry (ICC) for markers in cells from fine-needle aspirates of ascites. We used LBC, based on SurePath^TM (BD Diagnostics) technology, to screen 96 peritoneal fluid samples from patients with known malignancies and from 10 control patients with cirrhosis. Following dual ICC staining for cytokeratin 7 (CK7) and paired box gene 8 (PAX8), we developed an algorithm using immunoreactivity and three-dimensional (3D) cluster patterns to correlate staining and 3D cluster patterns with common primary origins that included stomach, ovarian, pancreatobiliary tract, colon, lung, and breast cancers. With the application of an automatic digitalized image analyzer, competence performance was analyzed using receiver operating characteristics (ROC) curve analysis. CK7 and PAX8 staining and 3D cluster patterns were used to differentiate primary origins. Samples from patients with stomach cancer were no 3D cluster /CK7⁺/PAX8^- with area under the curve (AUC) of 0.8699 in ROC curve analysis. Samples from ovarian cancer patients were large 3D cluster/CK7⁺/PAX8⁺ with AUC of 0.9812. Samples from pancreatobiliary tract cancer patients were small 3D cluster/CK7⁺/PAX8^- with AUC of 0.8772. The remaining cancer samples, including breast, lung and colon cancer samples, had similar patterns of large 3D clusters/CK7⁺/PAX8^- with AUC of 0.882, especially for lung cancer. SurePath^TM technology, using 3D cluster patterns and dual ICC for CK7 and PAX8 in peritoneal fluid samples, can provide important information for determining specific primary origins in cases of unknown primary carcinoma.

Primary ovarian signet ring cell carcinoma: A rare case report

Signet ring cell carcinoma (SRCC) of the ovary is most commonly metastatic from a primary lesion. Primary ovarian SRCC is rare, and the distinction between primary and metastatic SRCC of the ovary may be difficult. We herein present a case of primary SRCC of the ovary in a 54-year-old woman presenting with a right ovarian mass sized 20.5×16.5×11.5 cm. Total abdominal hysterectomy with bilateral salpingo-oophorectomy, partial omentectomy and incidental appendectomy were performed. Upon histological examination, mucinous carcinoma composed predominantly of signet ring cells was observed in the right ovary. The results of immunohistochemical examination included diffuse positivity for cytokeratin (CK)7 and CK20, but the tumor was negative for estrogen receptor, progesterone receptor, caudal type homeobox 2 and Wilms' tumor gene 1. A preoperative computed tomography (CT) scan of the abdomen and a postoperative positron emission tomography-CT scan did not reveal any suspicious extraovarian lesions. Based on the histological and clinicoradiological examinations, this case was diagnosed as a primary ovarian SRCC.

Collision tumor consisting of a colorectal adenocarcinoma and dissemination of a gastric adenocarcinoma

Background:

Collision tumors, composed of histologically distinct tumor types, are rare entities, especially in the colorectum, and corresponding evidence-based clinical management or treatment strategies are poorly defined. This is the first report of a collision tumor composed of two histologically distinct adenocarcinomas.

Case presentation:

A 78-year-old male showed severe anemia and a 10% body weight loss over 1 month. Preoperative examination revealed T3N1M0 stage IIIA gastric cancer and T3N0M0 stage IIA rectal cancer. Distal gastrectomy and rectectomy with regional lymph node dissection were performed. Immunohistochemistry revealed two distinct adenocarcinomas with gland duct structures – a colorectal adenocarcinoma and a disseminated gastric adenocarcinoma – that had collided to form an invasive tumor on the serosal surface of the anterior rectum wall.

Conclusion:

This extremely rare case of a collision tumor supports that precise immunohistochemical identification of all tumor components is needed for guiding decisions affecting overall prognosis, adjuvant treatment and survival.

Immunohistochemical staining of cytokeratin 20 and cytokeratin 7 in colorectal carcinomas: Four different immunostaining profiles

BACKGROUND/AIM

Aberrant expression of CK20/CK7 is reported in a percentage of colorectal carcinomas (CRC); however, its relation to clinicopathological variables and survival data is still unclear. The objective of this study is to explore patterns of CK20/CK7 immunostaining in CRC and to analyse the diagnostic, prognostic, and predictive role of patterns of CK20/CK7 immunostaining.

MATERIALS AND METHODS

A total of 144 CRC cases were retrieved from the archives at the Department of Pathology, King Abdulaziz University, Jeddah, Saudi Arabia. Immunohistochemistry was performed using antibody to CK7 and CK20. Immunostaining was defined as low and high by using the extent of staining. The association of CK7 and CK20 with clinicopathological characteristics and survival.

RESULTS

CK20 was expressed in a higher percentage of CRC and nodal metastasis than CK7. No difference in CK7 and CK20 immunostaining in primary and metastasis carcinomas was found. Four patterns of CK20/CK7 were identified; CK20+/CK7- (60.4%), CK20+/CK7+ (2.1%), CK20-/CK7- (35.4%), and CK20-/CK7+ (2.1%). There was no statistically significant correlation between CK20/CK7 immunohistochemical profile and clinicopathological characteristics, prognosis, and survival was determined.

CONCLUSIONS

Our results may support the heterogeneity of CRC. CRC showed four different subclasses following patterns of relative CK20/CK7 immunostaining. A considerable number of CRC expressed aberrant immune profile of CK20/CK7, which should be considered during diagnosing CRC in metastatic regions. Further studies on larger cohorts correlating different immunohistochemical cytokeratin profiles to molecular subtypes of CRC are recommended for better understanding of pathogenesis and behaviour of CRC.

Differential expression of CK20, β-catenin, and MUC2/5AC/6 in Lynch syndrome and familial colorectal cancer type X

BACKGROUND

Hereditary non-polyposis colorectal cancer comprises Lynch syndrome and familial colorectal cancer type X (FCCTX). Differences in genetics, demographics and histopathology have been extensively studied. The purpose of this study is to characterize their immunoprofile of markers other than MMR proteins.

METHODS

We compared the expression patterns of cytokeratins (CK7 and CK20), mucins (MUC2/5 AC/6), CDX2 and β-catenin in Lynch syndrome and FCCTX.

RESULTS

Differences were identified for CK20 and nuclear β-catenin, which were significantly more often expressed in FCCTX than in Lynch syndrome (p < 0.001), whereas MUC2, MUC5AC and MUC6 were overexpressed in Lynch syndrome tumors compared with FCCTX tumors (p = 0.001, < 0.01, and < 0.001, respectively). We observed no differences in the expression patterns of CK7 and CDX2.

CONCLUSIONS

In summary, we identified significant differences in the immunoprofiles of colorectal cancers linked to FCCTX and Lynch syndrome with a more sporadic-like profile in the former group and a more distinct profile with frequent MUC6 positivity in the latter group.

Altered expression of cytokeratin 7 and CD117 in transitional mucosa adjacent to human colorectal cancer

The multi-step progression of colorectal cancer through precancerous lesions (adenoma and dysplasia) is associated with cumulative molecular alterations, a number of which have also been demonstrated to be present in morphologically normal transitional mucosa adjacent to colorectal cancer. The cytoskeletal protein cytokeratin 7 (CK7) and the receptor tyrosine kinase, KIT proto-oncogene receptor tyrosine kinase (CD117), encoded by the proto-oncogene c-Kit, are lacking in normal colorectal crypt epithelium and are aberrantly expressed in a subset of colorectal cancer. The aim of the present study was to evaluate the expression of CK7 and CD117 in morphologically normal transitional mucosa adjacent to colorectal cancer. Immunohistochemical staining for CK7 and CD117 was performed in the mucosa adjacent to five groups of surgically resected colorectal tumors [low-grade adenoma, high-grade adenoma, mucosal adenocarcinoma, small-sized invasive adenocarcinoma (≤2 cm) and large-sized invasive adenocarcinoma (>2 cm)]. CK7 was expressed in the mucosa adjacent to a subset of colorectal tumors, and the positivity ratio increased according to tumor grade from low-grade adenoma up to small-sized invasive adenocarcinoma (61.2%). However, the positivity ratio of CK7 in the mucosa adjacent to the large-sized invasive adenocarcinoma (25.0%) was significantly lower compared with that of the next lower grade. CD117 was also expressed in the mucosa adjacent to a subset of colorectal tumors. In contrast to CK7, the positivity ratio of CD117 increased according to tumor grade from low-grade adenoma all the way through to the large-sized invasive adenocarcinoma (45.0%). Based on these results, the mechanism of CK7 and CD117 expression in the transitional mucosa adjacent to colorectal cancer may be different, and analysis of their individual expression may provide novel insights into the development and progression of colorectal cancer.

Combination of cadherin-17 and SATB homeobox 2 serves as potential optimal makers for the differential diagnosis of pulmonary enteric adenocarcinoma and metastatic colorectal adenocarcinoma

Background

Pulmonary enteric adenocarcinoma (PEAC), a rare type of non-small cell lung cancer, has similar histological and immunohistochemical morphology to colorectal adenocarcinoma. Cadherin-17 (CDH17) and SATB homeobox 2 (SATB2) immunoexpression have recently been demonstrated in colorectal adenocarcinoma. In this study, we evaluated the value of CDH17 and SATB2 in the diagnosis of pulmonary enteric adenocarcinoma and metastatic colorectal adenocarcinoma.

Methods

A total of 13 PEAC cases and 27 metastatic colorectal adenocarcinoma cases were enrolled in our cohort study. We analyzed the expressions of CK7, CK20, CDX-2, villin, cadherin-17 (CDH17), and SATB homeobox 2 (SATB2) using immunohistochemistry. Staining intensity and percentage of positive-staining cells were recorded. Sensitivity and specificity values for immunostains, individually and in combination, were computed and compared.

Results

Combining CDH17 and SATB2 resulted in high sensitivity (76.92%) and specificity (100%). In our study, the use of CK7+, napsin A+, TTF-1+, napsin A+TTF-1+ in combination with CDH17-/SATB2- had a higher area under the curve compared to the combination CDH17-/SATB2-. However, no significant differences were observed between the combination CDH17-/SATB2- and other combinations (P>0.05).

Conclusions

In combination, CDH17 and SATB2 serve as potential optimal markers for the differential diagnosis of PEAC and metastatic colorectal adenocarcinoma.

High KRT8 expression promotes tumor progression and metastasis of gastric cancer

Keratin8 (KRT8) is the major component of the intermediate filament cytoskeleton and predominantly expressed in simple epithelial tissues. Aberrant expression of KRT8 is associated with multiple tumor progression and metastasis. However, the role of KRT8 in gastric cancer (GC) remains unclear. In this study, KRT8 expression was investigated and it was found to be upregulated along with human GC progression and metastasis at both mRNA and protein levels in human gastric cancer tissues. In addition, KRT8 overexpression enhanced the proliferation and migration of human gastric cancer cells, whereas the knock‐down of KRT8 by siRNA only inhibited migration of human gastric cancer cells. Integrinβ1‐FAK‐induced epithelial‐mesenchymal‐transition (EMT) only existed in the high KRT8 cells. Furthermore, KRT8 overexpression led to increase in p‐smad2/3 levels and TGFβ dependent signaling events. KRT8 expression in GC was related to tumor clinical stage and worse survival. Kaplan–Meier analysis proved that KRT8 was associated with overall survival of patients with GC that patients with high KRT8 expression tend to have unfavorable outcome. Moreover, Cox's proportional hazards analysis showed that high KRT8 expression was a prognostic marker of poor outcome. These results provided that KRT8 expression may therefore be a biomarker or potential therapeutic target to identify patients with worse survival.

CDH17 Is a More Sensitive Marker for Gastric Adenocarcinoma Than CK20 and CDX2

CONTEXT

-CDH17, which is expressed in the intestinal epithelium, is a novel oncogene involved in tumor invasion and metastasis. A panel consisting of cytokeratin (CK) 7, CD20, and CDX2 antibodies is typically used to diagnose gastrointestinal adenocarcinomas. However, studies have shown that CDH17 is a highly specific marker for gastrointestinal adenocarcinoma and may be important in clinical diagnosis.

OBJECTIVE

-To evaluate the sensitivity and specificity of CDH17, CK20, and CDX2 antibodies in neoplastic tissues, with emphasis on colon, stomach, and esophageal gastrointestinal lineage.

DESIGN

-Immunohistochemistry was performed with CDH17, CK20, and CDX2 antibodies on formalin-fixed, paraffin-embedded tissue microarrays from normal (n = 26) and neoplastic (n = 884) tissues.

RESULTS

-CDH17 immunostaining was positive in 97.3% (145 of 149) of colon adenocarcinomas, whereas CK20 and CDX2 stained positively in 88.6% (132 of 149) and 93.3% (139 of 149), respectively. In metastatic colon cancers, CDH17, CK20, and CDX2 positive staining was observed in 90.6% (29 of 32), 59.4% (19 of 32), and 81.3% (26 of 32) of cases, respectively. In stomach adenocarcinomas, CDH17 positively stained 64.0% (112 of 175) of tissues, compared to CK20 and CDX2, where staining was observed in only 24.6% (43 of 175) and 46.9% (82 of 175), respectively. In esophageal adenocarcinomas, CDH17, CK20, and CDX2 stained 38.7% (12 of 31), 25.8% (8 of 31), and 29% (9 of 31) of specimens, respectively. Low or no expression was observed in other neoplastic tissues, except pancreatic cancers, where CDH17 displayed higher expression than CK20 and CDX2.

CONCLUSIONS

-CDH17 is a specific and more sensitive marker in the gastrointestinal tract than CK20 and CDX2. CDH17 may be especially valuable when gastrointestinal tumors are suspected in cancers of unknown primary.

Gastric neuroendocrine tumor treated with endoscopic submucosal dissection

A case of a 59-year-old male patient with gastric neuroendocrine tumor which was misdiagnosed as adenocarcinoma, is presented. Herein, primary diagnosis was made due to the similarity of endoscopic pictures of both diseases and dues to the inappropriate interpretation of a small biopsy sample. The patient was qualified for endoscopic submucosal dissection. Microscopic examination of whole lesion, supplemented by immmunohistochemical reactions (chromogranin A, synaptophysin, cytokeratins 7 and 20, Ki67) revealed gastric neuroendocrine tumor (NET) G2.

The lesson learnt is that to provide effective treatment to the patient, it is necessary to use all available methods to make a proper diagnosis and to distinguish the suspected disease from others with similar features.

Metastatic pattern of invasive lobular carcinoma of the breast-Emphasis on gastric metastases

BACKGROUND AND OBJECTIVES

Breast invasive ductal carcinoma (IDC) and invasive lobular carcinoma (ILC) have different metastatic patterns, but the exact pattern of metastases from ILC is poorly known. This study aimed to determine the frequency of ILC metastases in atypical locations, with an emphasis on gastric metastases.

METHODS

Patients with ILC treated at the Saint-Sacrement Hospital (Quebec City, Canada) and the Maisonneuve-Rosemont Hospital (Montreal, Canada) between January 2003 and December 2009 were retrospectively reviewed. Demographic, clinical, and follow-up data were retrieved from the medical charts. Metastases that were diagnosed during follow-up were recorded.

RESULTS

Among the 481 patients with ILC, 74 (15.4%) were diagnosed with metastases after a median follow-up of 46 months. Among these 74 patients, 41.9% had metastases in atypical sites. Five patients were diagnosed with histologically confirmed gastric metastases of ILC.

CONCLUSION

Metastases of breast ILC to atypical sites might be more frequent than previously reported. Clinicians should keep a high level of suspicion when a patient with a history of ILC develops digestive symptoms. It is important to differentiate metastases from a primary GI tumor by using immunohistochemical markers. J. Surg. Oncol. 2016;114:543-547. © 2016 Wiley Periodicals, Inc.

[A Case of Advanced Gastric Cancer Presenting as Multiple Colonic Lymphoid Hyperplasia]

Gastric cancer frequently disseminates to the liver, lung, and bone via hematogeneous, lymphatic, or peritoneal routes. However, gastric adenocarcinoma that metastasize to the colon and that shows typical linea platisca pattern on colonofiberscopy has rarely been reported. Recently, the authors experience a case of advanced gastric cancer with colonic metastases in a 55-year-old female patient. Multiple colonic lymphoid hyperplasias were detected on colonofiberscopy and biopsy revealed metastatic gastric cancer to the colonic wall. She was treated with mFOLFOX (5-FU, oxaliplatin, leucovorin) and has achieved stable disease status without disease progression. Herein, we report a rare case of signet ring-cell gastric cancer which metastasized to the colon in the form of multiple colonic lymphoid hyperplasias.

Sigmoid colonic metastasis by lymphatic spread occurring with unilateral Krukenberg tumor considered to be caused by stage IA early gastric cancer: A case report

Gastric cancer is one of the most common malignancies in Asia, and the second most common cause of cancer-associated mortality in Japan. Colorectal metastases originating from gastric adenocarcinoma are extremely rare. The present study reports an unusual case of lymphogenous sigmoid metastasis of gastric adenocarcinoma occurring in a 58-year-old female patient. Endoscopic and radiological findings were indicative of 0-IIc+IIa early gastric cancer, and radical distal gastrectomy with D2 lymph node dissection was performed. The pathological diagnosis was stage IA gastric adenocarcinoma (T1bN0M0), according to the Japanese classification of gastric cancer. A follow-up examination at 18 months post surgery revealed a recurrence of paraaortic lymph node metastasis, detected by abdominal computed tomography (CT) and positron emission tomography (PET)/CT. The patient received chemotherapy with S-1 and cisplatin. Subsequently, radiotherapy was administered to the paraaortic lymph nodes at levels Th11-L3. Follow-up abdominal CT and PET/CT revealed an enlarged left ovary, and abnormal uptake in the left ovary and sigmoid colon. An oophorectomy and sigmoidectomy with D3 lymph node dissection were performed. The pathological diagnosis was metastatic adenocarcinoma; this was identical to the gastric pathology in the previous pathological report. The patient continued treatment with chemotherapy. Although sigmoid colonic metastasis from gastric cancer is extremely rare, metastasis from gastric cancer must be considered during the differential diagnosis of cases involving a colorectal mass and a previous history of gastric cancer.

A novel role for flotillin-1 in H-Ras-regulated breast cancer aggressiveness

Elevated expression and aberrant activation of Ras have been implicated in breast cancer aggressiveness. H-Ras, but not N-Ras, induces breast cell invasion. A crucial link between lipid rafts and H-Ras function has been suggested. This study sought to identify the lipid raft protein(s) responsible for H-Ras-induced tumorigenicity and invasiveness of breast cancer. We conducted a comparative proteomic analysis of lipid raft proteins from invasive MCF10A human breast epithelial cells engineered to express active H-Ras and non-invasive cells expressing active N-Ras. Here, we identified a lipid raft protein flotillin-1 as an important regulator of H-Ras activation and breast cell invasion. Flotillin-1 was required for epidermal growth factor-induced activation of H-Ras, but not that of N-Ras, in MDA-MB-231 triple-negative breast cancer (TNBC) cells. Flotillin-1 knockdown inhibited the invasiveness of MDA-MB-231 and Hs578T TNBC cells in vitro and in vivo. In xenograft mouse tumor models of these TNBC cell lines, we showed that flotillin-1 played a critical role in tumor growth. Using human breast cancer samples, we provided clinical evidence for the metastatic potential of flotillin-1. Membrane staining of flotillin-1 was positively correlated with metastatic spread (p = 0.013) and inversely correlated with patient disease-free survival rates (p = 0.005). Expression of flotillin-1 was associated with H-Ras in breast cancer, especially in TNBC (p < 0.001). Our findings provide insight into the molecular basis of Ras isoform-specific interplay with flotillin-1, leading to tumorigenicity and aggressiveness of breast cancer.

Clinicopathologic and molecular characteristics of gastric cancer showing gastric and intestinal mucin phenotype

Gastric cancer (GC), one of the most common human cancers, can be classified into gastric or intestinal phenotype according to mucin expression. TP53 mutation, allelic deletion of the APC gene and nuclear staining of β-catenin are frequently detected in the intestinal phenotype of GC, whereas CDH1 gene mutation, microsatellite instability and DNA hypermethylation of MLH1 are common events in the gastric phenotype of GC. Our Serial Analysis of Gene Expression (SAGE) and Escherichia coli ampicillin secretion trap (CAST) analyses revealed that CDH17, REG4, OLFM4, HOXA10, DSC2, TSPAN8 and TM9SF3 are upregulated in GC and that CLDN18 is downregulated in GC. Expression of CDH17, REG4, HOXA10 and DSC2 and downregulation of CLDN18 are observed in the intestinal phenotype of GC. In contrast, OLFM4 is expressed in the gastric phenotype of GC. Expression of TSPAN8, TM9SF3 and HER2 are not associated with either gastric or intestinal phenotypes. Ectopic CDX2 expression plays a key function in the GC intestinal phenotype. MUC2, CDH17, REG4, DSC2 and ABCB1 are direct targets of CDX2. Importantly, these genes encode transmembrane/secretory proteins, indicating that the microenvironment as well as cancer cells are also different between gastric and intestinal phenotypes of GC.

[Morphology of secondary ovarian tumors and metastases]

The distinction between primary and secondary (metastatic) ovarian tumors is essential for the selection of appropriate surgical interventions, chemotherapeutic treatment and prognostic evaluation for the patient. Metastatic tumors of the ovary range between 5 % and 30 %. The majority of ovarian metastases in Europe and North America derive from colorectal (25-50 %) and breast cancers (8-25 %). A major issue is the differential diagnosis of mucinous tumors. Major features favoring metastasis include bilaterality, size < 10 cm, ovarian surface involvement, extensive intra-abdominal spread, and infiltrative growth within the ovary involving the corpus albicans and corpora lutea. An algorithm using bilaterality and tumor size (cut-off 10 cm) allows correct categorization in approximately  85 % of the cases. Although immunohistochemistry (especially CK7 and CK20 in mucinous tumors) using a panel of antibodies plays a valuable role and is paramount in the diagnosis, the results must be interpreted with caution and within the relevant clinical and histopathological context. It is necessary to note that the correct diagnosis of ovarian metastases always needs interdisciplinary and multidisciplinary approaches.

Pregnancy complicated by a Krukenberg tumor with an undetermined origin and its management

Krukenberg tumor in pregnancy is very rare and management of this condition is a dilemma for physicians. Moreover, the existence of a primary Krukenberg tumor is still in debate. Herein, we present a 29-year-old woman at 29 weeks of pregnancy, admitted with premature labor and revealed to have a signet ring cell ovarian tumor with an undetermined primary origin. A primary Krukenberg tumor or a Krukenberg tumor with an undetermined origin has not been previously reported in a pregnant patient. By virtue of the controversy, we are not eager to use the term 'primary Krukenberg tumor' for this case, although the possibility of the existence of this kind of tumor cannot be totally ignored.

Primary ovarian mucinous carcinoma with signet ring cells - report of a rare case

Presence of signet ring cells in ovarian neoplasms are commonly encountered in Krukenberg tumours of ovary. Unusual presence in primary ovarian mucinous tumours may create a diagnostic difficulty. To the best of our knowledge only very few such cases have been reported in the literature indicating their rarity. We report a case of primary ovarian mucinous carcinoma with signet ring cells. The purpose of this presentation is to sensitize the pathologists to consider primary mucinous carcinoma as a differential diagnosis in tumours with signet ring cells.

Aberrant cytokeratin expression as a possible prognostic predictor in poorly differentiated colorectal carcinoma

BACKGROUND AND AIM

The cytokeratin (CK)7(-) /CK20(+) immunoprofile is characteristic of colorectal carcinoma (CRC), although CK7(+) or CK20(-) phenotypes are occasionally encountered, particularly in histologically variant CRCs. We analyzed CK7/CK20 profiles in variant CRCs in association with clinicopathologic parameters and prognosis.

METHODS

CK expression in well- and moderately differentiated adenocarcinoma (WMDA) (n = 63), poorly differentiated adenocarcinoma (PDA) (n = 91), mucinous adenocarcinoma (MUA) (n = 81), signet-ring cell carcinoma (SRCC) (n = 15), undifferentiated carcinoma (UDC) (n = 12), and adenosquamous carcinoma (n = 2) was analyzed using immunohistochemistry. Cut-off scores were set at 1% for CK7 and 25% for CK20 using the receiver operating characteristic curve analysis of PDA. Association between CK20(-) and better prognosis in PDA was validated in the second cohort (n = 66).

RESULTS

CK7/CK20 immunoprofiling revealed a predominant CK7(-) /CK20(+) profile in WMDA, MUA, and SRCC, while the majority of UDC was characterized by a CK7(-) /CK20(-) profile. The CK7/CK20 profile in PDA was variable. Contingency table analysis revealed that CK expression was not significantly associated with any clinicopathologic parameters in WMDA, PDA, and MUA. However, survival analysis demonstrated that CK20(-) was significantly associated with better prognosis in PDA. Although CK20(-) was significantly associated with mismatch repair deficiency in PDA, it was an independent prognostic factor in multivariate analysis. Finally, we confirmed that CK20 status, determined using a 25% cut-off score, was a significant prognostic parameter in the second PDA cohort.

CONCLUSIONS

CK20 status may be used as a prognostic predictor of PDA.

Identification of annexin II as a novel secretory biomarker for breast cancer

Early prediction of metastatic breast cancer is important for improvement of prognosis and survival rate. The present study aimed to identify secreted protein biomarkers for detection of invasive breast cancer. To this end, we performed a comparative proteomic analysis by a combination of 2DE and MALDI-TOF MS analysis of conditioned media from invasive H-Ras MCF10A human breast epithelial cells and noninvasive MCF10A and N-Ras MCF10A cells. We identified a list of 25 proteins that were strongly detected in media of H-Ras MCF10A and focused on annexin II, which was shown to be involved in cell motility. Invasive triple-negative human breast carcinoma cells, Hs578T, and MDA-MB-231, showed increased levels of annexin II in media, demonstrating that secretion of annexin II correlated well with the invasive phenotype of cells. We demonstrated a crucial role of annexin II in breast cell invasion/migration and actin cytoskeleton reorganization required for filopodia formation. Annexin II levels in the plasma samples and breast cancer tissues of breast cancer patients were significantly higher than those of normal groups, providing a clinical relevance to our in vitro findings. Taken together, we identified annexin II as a novel secretory biomarker candidate for invasive breast cancer, especially estrogen receptor-negative breast cancer.

Metastatic colorectal carcinoma mimicking primary ovarian carcinoma presenting as 'giant' ovarian tumors in an individual with probable Lynch syndrome: a case report

Introduction

Ovarian metastases occur in 3 to 8% of women with primary colon cancer. In the setting of a pre-existing colorectal carcinoma this would constitute a hereditary non-polyposis colorectal cancer, Lynch 2 syndrome, accounting for 5 to 10% of colon cancer cases. We unveil a case of ‘giant’ ovarian tumors mimicking primary ovarian cancer; ostensibly the first reported in East Africa.

Case presentation

A 58-year-old African woman was diagnosed with colorectal adenocarcinoma in June 2009. She had a right hemicolectomy with the tumor staged as regional cancer, following histopathological examination. Chemotherapy was administered both adjuvantly and 1 year later for what was thought to be a recurrence of tumor. Despite this, her general condition deteriorated. Following re-evaluation and an exploratory laparotomy she was found to have bilateral ‘giant’ ovarian tumors, with peritoneal seedlings and subcutaneous metastases (colonic in origin). A bilateral salpingo-oophorectomy was done, accompanied by histopathological analysis with institution of chemotherapy for ovarian cancer. Following immunohistochemistry tests and microsatellite instability analysis it was found that the ovarian tumors were secondaries from the colon. She was also identified as a Lynch syndrome case or a case of sporadic microsatellite instability, although with no suggestive family cancer history. The treatment regimen was changed to suit metastatic disease.

Conclusions

The case presents a diagnostic and thus treatment conundrum. Two primary tumors (suspected Lynch syndrome) had been perceived yet there is actually only metastatic colorectal cancer. We also have a rare and unusual metastatic presentation: ‘giant’ bilateral ovarian tumors and subcutaneous nodules, concurrently. Further still, she is a case of probable Lynch syndrome, requiring genetic analysis for definitive classification and surveillance for hereditary non-polyposis colorectal cancer-associated cancers.

Important inferences are drawn. Firstly, ‘giant’ ovarian tumors diagnosed as primary ovarian cancer may actually be colonic secondaries. Secondly, immunohistochemistry and microsatellite instability analysis tests ought to be part of the diagnostic package in colon cancer management, particularly for identifying tumor origin and the Lynch syndrome (a condition which has had little attention in resource-limited countries). Thirdly, multidisciplinary team collaboration is emphasized in colorectal cancer management.

Challenging diagnosis of a jejunal adenocarcinoma with ovarian metastasis: report of an unusual case

We report the first documented case of ovarian metastasis from a jejunal primary adenocarcinoma in an Australian patient. The presentation was unusual, initially a suspicious abdominal nodule in the epigastric area, which turned out to be an adenocarcinoma of possible intestinal origin. Gastroscopy and colonoscopy were performed with no suspicious lesion identified. Abdominal and pelvic ultrasound imaging showed a complex pelvic mass suspicious of ovarian cancer. Laparoscopy was performed to exclude possibility of ovarian cancer and small bowel cancer. The ovarian mass showed similar features from the epigastric nodule, again suggestive of intestinal primary. Definitive diagnosis was obtained when the patient represented 2 months later with malignant bowel obstruction requiring palliative resection of the proximal jejunum. This case demonstrates the difficulty in diagnosing ovarian metastasis from a small bowel primary, which has the potential to mimic an ovarian primary tumour clinically, and a large bowel or ovarian primary pathologically.