Immunohistochemistry of colorectal carcinoma: current practice and evolving applications

Adenocarcinoma involving the urinary bladder

A man in his 70s previously diagnosed with an adenocarcinoma of the prostate, received external beam radiation therapy (EBRT) and brachytherapy 11 years ago. Ten years later, he developed urinary symptoms and a cystoscopy identified a bladder neck tumour. A transurethral resection of a bladder tumour was performed, and pathology revealed a high-grade adenocarcinoma consistent with a colorectal primary. A colonoscopy was unremarkable, and imaging studies showed tumour involving the bladder and prostate. Tumour markers and a CARIS genomic prevalence score also favoured a colorectal cancer primary.The patient refused surgery and underwent chemoradiation with a combination of EBRT and brachytherapy with concurrent capecitabine. Imaging studies obtained 6 months after reirradiation revealed an enlarged left-sided mesorectal lymph node concerning for disease recurrence. The lymph node was treated with Stereotactic Body Radiation Therapy and his post-treatment imaging revealed a response to treatment with no other evidence of disease.

A protein microarray-based serum proteomic investigation reveals distinct autoantibody signature in colorectal cancer

PURPOSE

Colorectal cancer (CRC) has been reported as the second leading cause of cancer death worldwide. The 5-year annual survival is around 50%, mainly due to late diagnosis, striking necessity for early detection. This study aims to identify autoantibody in patients' sera for early screening of cancer.

EXPERIMENTAL DESIGN

The study used a high-density human proteome array with approximately 17,000 recombinant proteins. Screening of sera from healthy individuals, CRC from Indian origin, and CRC from middle-east Asia origin were performed. Bio-statistical analysis was performed to identify significant autoantibodies altered. Pathway analysis was performed to explore the underlying mechanism of the disease.

RESULTS

The comprehensive proteomic analysis revealed dysregulation of 15 panels of proteins including CORO7, KCNAB1, WRAP53, NDUFS6, KRT30, and COLGALT2. Further biological pathway analysis for the top dysregulated autoantigenic proteins revealed perturbation in important biological pathways such as ECM degradation and cytoskeletal remodeling etc. CONCLUSIONS AND CLINICAL RELEVANCE: The generation of an autoimmune response against cancer-linked pathways could be linked to the screening of the disease. The process of immune surveillance can be detected at an early stage of cancer. Moreover, AAbs can be easily extracted from blood serum through the least invasive test for disease screening.

Unusual Case of Pancreatic Adenocarcinoma with Bladder Metastasis

Background: The pancreas can be the site of neoplasms of several histogenetic origins; in most cases, tumors derive from the exocrine component, and ductal adenocarcinoma certainly prevails over the others. This tumor displays remarkably aggressive behavior, and it is often diagnosed at a late stage of disease. Case presentation: We discuss the rare case of a 76-year-old male with locally advanced pancreatic head adenocarcinoma who developed uncommon metastatic disease. The bladder constitutes a very rare site of metastases, mostly deriving from melanoma, gastric, lung and breast cancers. The bladder's secondary involvement in pancreatic malignancies represents an extremely unusual occurrence, and there are very few cases described in the literature to date. Conclusions: The finding of pancreatic adenocarcinoma metastases leads to a poor prognosis, and patients who are diagnosed at this stage constitute 53% of cases, with a 5-year survival of 3%. Although rare, therefore, the diagnostic hypothesis of pancreatic ductal adenocarcinoma (DAC) metastases to the bladder must, in some cases, be considered, especially if accompanied by a clinical picture that may suggest it.

The Diagnostic Value of Cadherin 17 and CDX2 Expression as Immunohistochemical Markers in Colorectal Adenocarcinoma

BACKGROUND

Colorectal cancer is a major cause of morbidity and mortality throughout the world. Although the diagnosis of colorectal cancer is straightforward in primary site, yet it may represent a diagnostic problem in metastatic tumor of unknown primary origin. Hence, immunohistochemical analysis in combination with morphologic assessment and correlation with clinical data becomes crucial, because it is important to specify the primary site of metastasis since some specific tumor types may respond well to targeted molecular therapies. Therefore, establishment of reliable diagnostic markers that confirm or rule out colorectal origin is mandatory.

AIM

To study the expression of cadherin 17 and CDX2 in colorectal carcinoma and to evaluate their diagnostic roles in identifying metastatic colonic from non-colonic adenocarcinomas in cancer of unknown primary site.

DESIGN AND METHODS

This retrospective study included 65 cases of adenocarcinomas: 35 cases of colorectal adenocarcinoma (primary or metastatic) and 30 cases of non-colorectal adenocarcinoma. They were retrieved from the archives of Pathology Department of Ain Shams University and Ain Shams University Specialized Hospitals during the period from 2010 to 2015. Immunohistochemical study was performed using cadherin 17 and CDX2 antibodies.

RESULTS

The sensitivity and specificity of CDX2 and cadherin 17 are 97.1% and 53.3% and 100% and 50% in detecting colonic adenocarcinoma respectively. The PPV, NPV, and overall accuracy of CDX2 versus cadherin 17 were 70.8%, 94.1%, and 76.9% versus 70%, 100%, and 76.9% respectively.

CONCLUSION

Cadherin 17 is a more sensitive marker than CDX2 in diagnosis of carcinoma of unknown primary site especially when colorectal carcinoma is suspected.

Adjuvant radiation therapy for T4 non-rectal colon adenocarcinoma provides a cause-specific survival advantage: A SEER database analysis

PURPOSE

While there is no level 1 evidence supporting the use of adjuvant radiotherapy (RT) for non-rectal colon cancer in the modern chemotherapy era, there are studies that suggest a local control benefit. This treatment modality is not part of standard treatment recommendations, and we hypothesized that adjuvant RT provides a benefit in locally advanced disease. Due to the limited number who receive post-operative RT, a national database was searched to provide sufficient power.

MATERIALS AND METHODS

A retrospective analysis using the Surveillance, Epidemiology, and End Results (SEER) database was performed. Inclusion criteria were: non-rectal colon cancer, AJCC 6th or 7th edition T4 and M0, oncologic resection, and 1st cancer site. Patients were excluded for RT prior to or during surgery, or if the sequence of RT was unknown. Using a Cox proportional hazard model, the relative risk of cause-specific mortality for "RT after surgery" versus "No RT" was calculated.

RESULTS

21,789 patients were identified who met the inclusion criteria. Of these, only 1001 received adjuvant RT, and 64% were node-positive (53% RT vs. 65% no RT). When comparing RT vs. no RT, after adjusting for sex, age, N stage, and grade, we determined the relative risk of death from cancer was 0.8849 (95% CI: 0.8008-0.9779; p = 0.0165), suggesting that only 14 patients with T4 disease need receive adjuvant radiation to spare a cancer-related death.

CONCLUSIONS

Adjuvant RT is not routinely utilized for definitive treatment of T4 non-rectal colon cancer, but this analysis shows a significant cause-specific survival benefit.

Raman spectroscopy for the diagnosis of unlabeled and unstained histopathological tissue specimens

AIM

To investigate the possibility of diagnosing gastric cancer from an unstained pathological tissue using Raman spectroscopy, and to compare the findings to those obtained with conventional histopathology.

METHODS

We produced two consecutive tissue specimens from areas with and without cancer lesions in the surgically resected stomach of a patient with gastric cancer. One of the two tissue specimens was stained with hematoxylin and eosin and used as a reference for laser irradiation positioning by the spectroscopic method. The other specimen was left unstained and used for Raman spectroscopy analysis.

RESULTS

A significant Raman scattering spectrum could be obtained at all measurement points. Raman scattering spectrum intensities of 725 cm^-1 and 782 cm^-1, are associated with the nucleotides adenine and cytosine, respectively. The Raman scattering spectrum intensity ratios of 782 cm^-1/620 cm^-1, 782 cm^-1/756 cm^-1, 782 cm^-1/1250 cm^-1, and 782 ​​cm^-1/1263 cm^-1 in the gastric adenocarcinoma tissue were significantly higher than those in the normal stomach tissue.

CONCLUSION

The results of this preliminary experiment suggest the feasibility of our spectroscopic method as a diagnostic tool for gastric cancer using unstained pathological specimens.

Practical Immunohistochemistry in Neoplastic Pathology of the Gastrointestinal Tract, Liver, Biliary Tract, and Pancreas

CONTEXT

- Immunomarkers with diagnostic, therapeutic, or prognostic values have been increasingly used to maximize the benefits of clinical management of patients with neoplastic diseases of the gastrointestinal tract, liver, biliary tract, and pancreas.

OBJECTIVES

- To review the characteristics of immunomarkers that are commonly used in surgical pathology practice for neoplasms of the gastrointestinal tract, liver, biliary tract, and pancreas, and to summarize the clinical usefulness of immunomarkers that have been discovered in recent years in these fields.

DATA SOURCES

- Data sources include literature review, authors' research data, and personal practice experience.

CONCLUSIONS

- Immunohistochemistry is an indispensable tool for the accurate diagnosis of neoplastic diseases of the gastrointestinal tract, liver, biliary tract, and pancreas. Useful immunomarkers are available to help distinguish malignant neoplasms from benign conditions, determine organ origins, and subclassify neoplasms that are morphologically and biologically heterogeneous. Specific immunomarkers are also available to help guide patient treatment and assess disease aggressiveness, which are keys to the success of personalized medicine. Pathologists will continue to play a critical role in the discovery, validation, and application of new biomarkers, which will ultimately improve patient care.

CAR-T cell therapy in gastrointestinal tumors and hepatic carcinoma: From bench to bedside

The chimeric antigen receptor (CAR) is a genetically engineered receptor that combines a scFv domain, which specifically recognizes the tumor-specific antigen, with T cell activation domains. CAR-T cell therapies have demonstrated tremendous efficacy against hematologic malignancies in many clinical trials. Recent studies have extended these efforts to the treatment of solid tumors. However, the outcomes of CAR-T cell therapy for solid tumors are not as remarkable as the outcomes have been for hematologic malignancies. A series of hurdles has arisen with respect to CAR-T cell-based immunotherapy, which needs to be overcome to target solid tumors. The major challenge for CAR-T cell therapy in solid tumors is the selection of the appropriate specific antigen to demarcate the tumor from normal tissue. In this review, we discuss the application of CAR-T cells to gastrointestinal and hepatic carcinomas in preclinical and clinical research. Furthermore, we analyze the usefulness of several specific markers in the study of gastrointestinal tumors and hepatic carcinoma.

Nuclear aldehyde dehydrogenase 1A1 (ALDH1A1) expression is a favorable prognostic indicator in colorectal carcinoma

AIM

To assess the expression pattern of aldehyde dehydrogenase 1A1 (ALDH1A1) in the normal-adenoma-primary carcinoma-liver metastasis sequence, and investigate its association with clinicopathological features and outcomes.

METHODS

Immunohistochemistry for ALDH1A1 was performed on two cohorts. One used tissue microarrays (TMAs) of 395 primary colorectal carcinomas, and the other used whole-tissue sections from 217 adenomas, 265 primary carcinomas, and 72 liver metastatic carcinomas. Both the epithelial and stromal expression of ALDH1A1 were evaluated. Both cytoplasmic and nuclear expression were assessed in epithelial cells.

RESULTS

In the TMA and whole-tissue cohorts, univariate analysis indicated that the cytoplasmic expression of ALDH1A1 cannot be considered as a prognosis marker of CRCs. In the whole-tissue cohort, nuclear expression was found in a small subgroup of CRC patients. Here, both univariate and multivariate analysis showed that nuclear expression was significantly associated with longer disease-specific survival. In addition, we found that nuclear expression in low-grade adenoma was predominant over high-grade adenoma, primary CRC and the correpsonding liver metastasis.

CONCLUSIONS

Whole-tissue is better than TMA for the detection of ALDH1A1 nuclear staining in CRC patients, and nuclear expression is associated with a better outcome. Cytoplasmic expression is not a suitable prognostic marker of CRC.

Application of immunohistochemistry in gastrointestinal and liver neoplasms: new markers and evolving practice

CONTEXT

Diagnosis of primary gastrointestinal and liver neoplasms is usually straightforward. Immunohistochemistry is most helpful to differentiate metastatic carcinomas with morphologic similarity and to resolve tumors of unknown origin. Recently, several new markers highly sensitive and specific for primary liver and gastrointestinal tumors have been discovered. Their potential diagnostic application has not been widely appreciated by general practicing pathologists. In addition, a new trend in immunohistochemistry application has started, focusing on assessing predictive markers (such as human epidermal growth factor receptor 2) and mutation-specific markers (v-raf murine sarcoma viral oncogene homolog B V600E) to directly guide clinical management. Practicing pathologists need to be aware of and prepared for this evolving trend.

OBJECTIVES

To summarize the usefulness of several recently discovered immunohistochemical markers in the study of gastrointestinal and liver tumors; to suggest the most current and effective immunohistochemical panels addressing common diagnostic challenges for these tumors; to share practical experience and useful tips for human epidermal growth factor receptor 2 testing in gastric and gastroesophageal junction adenocarcinoma and v-raf murine sarcoma viral oncogene homolog B V600E immunohistochemistry in colorectal carcinoma.

DATA SOURCES

Sources include literature review, and authors' research data and practice experience. The cases illustrated are selected from the pathology archives of the Geisinger Medical Center (Danville, Pennsylvania).

CONCLUSIONS

Application of immunohistochemistry in gastrointestinal and liver tumors continues to evolve. New tumor-specific markers constantly emerge and help pathologists to further improve diagnostic accuracy. Assessment of predictive and prognostic markers by immunohistochemistry in routine pathologic diagnosis is a new trend and will greatly facilitate the advancement of personalized cancer therapy.

[The role of pathology in the diagnostics of CUP syndrome]

Cancers of unknown primary (CUP) origin account for 2-3 % of all malignancies in Germany and represent a heterogeneous, often aggressive and clinically challenging group of tumors with early metastatic dissemination for which a standardized diagnostic work-up initially fails to identify the primary site of origin at the time of diagnosis. This article reviews the options and challenges of tissue-based conventional as well as molecular diagnostic procedures to categorize this heterogeneous group of neoplasms. The role of pathology in the diagnostics of CUP syndrome is described as part of a multidisciplinary effort involving oncologists, surgeons and radiologists with the ultimate goal of assisting clinical reasoning and decision-making.

SATB2 is a novel marker of osteoblastic differentiation and colorectal adenocarcinoma

SATB2 is a nuclear matrix-associated transcription factor and epigenetic regulator that is involved in osteoblastic differentiation and is also expressed in the glandular epithelial cells of the lower gastrointestinal tract. Recent studies have shown that, because of its relative specificity for osteoblastic differentiation, SATB2 immunostaining could potentially be a useful adjunct for assisting in the differential diagnosis of both benign and malignant osteogenic tumors. In addition, because SATB2 is also a highly sensitive and specific marker for colorectal adenocarcinomas, it could also serve as a complementary marker in the differential diagnosis of a carcinoma of unknown primary origin.