Immunohistochemical Study and Clinicopathologic Correlation of Cox-2 and Her-2 Expression in Colorectal Carcinoma: A 5-Year Retrospective Study.

BACKGROUND: Colorectal cancer (CRC) is the fourth most common cancer in Nigeria, and it affects mostly persons in their middle age. In a bid to gain some insight into the molecular characteristics of CRC in our environment, we set out to investigate the expression of COX-2 and HER-2 among Nigerian subjects. OBJECTIVES: To evaluate the expression of COX-2 and HER-2 and determine their correlation with clinicopathologic parameters in surgically resected histologically diagnosed cases of colorectal cancer. METHODS: Fifty-three paraffin-embedded tissue blocks of colorectal resections and corresponding patient information were retrieved from the archives of the Anatomic and Molecular Pathology Department of Lagos University Teaching Hospital. A 4-micron slide section was obtained from each specimen and immunohistochemistry for COX-2 and HER-2 expression was performed. RESULTS: Mean age of cases was 53.9years with an almost equal M:F ratio of 1.12:1. Half of the cases were moderately differentiated adenocarcinoma and 17% were high grade tumors. Eighty three percent of the tumours showed positive cytoplasmic COX-2 expression and extremely low membranous HER-2 positivity was observed in 2%. There was no significant correlation between COX-2 expression and age, gender, tumour location, tumour size, depth of invasion or lymph node status. However, COX-2 expression revealed a significant correlation with tumour grade (p= 0.013). CONCLUSION: This study detects a high COX-2 and low HER- 2 expression in colorectal cancer using immunohistochemistry, suggesting a possible role for COX-2 in CRC pathogenesis. This report should trigger further investigations of both markers vis-à-vis the management of CRC in our environment.

CONTEXTE: Le cancer colorectal (CCR) est le quatrième cancer le plus fréquent au Nigeria et il touche surtout les personnes d'âge moyen. Dans le but de mieux comprendre les caractéristiques moléculaires du CCR dans notre environnement, nous avons entrepris d'étudier l'expression de COX-2 et de HER-2 chez les sujets nigérians. OBJECTIFS: Évaluer l'expression de COX-2 et HER-2 et déterminer leur corrélation avec les paramètres clinicopathologiques dans les cas de cancer colorectal diagnostiqués histologiquement et réséqués chirurgicalement. MÉTHODES: Cinquante-trois blocs de tissus inclus en paraffine provenant de résections colorectales et les informations correspondantes sur les patients ont été récupérés dans les archives du département de pathologie anatomique et moléculaire du Lagos University Teaching Hospital. Une section de lame de 4 microns a été obtenue de chaque spécimen et une immunohistochimie pour l'expression de COX-2 et HER-2 a été réalisée. RÉSULTATS: L'âge moyen des cas était de 53,9 ans avec un rapport M:F presque égal de 1,12:1. La moitié des cas étaient des adénocarcinomes modérément différenciés et 17% des tumeurs de haut grade. Quatre-vingt-trois pour cent des tumeurs présentaient une expression cytoplasmique positive de la COX-2 et une positivité HER-2 membranaire extrêmement faible a été observée dans 2 % des cas. Il n'y avait pas de corrélation significative entre l'expression de la COX-2 et l'âge, le sexe, la localisation de la tumeur, la taille de la tumeur, la profondeur de l'invasion ou le statut des ganglions lymphatiques. Cependant, l'expression du COX-2 a révélé une corrélation significative avec le grade de la tumeur (p= 0,013). CONCLUSION: Cette étude détecte une forte expression de COX- 2 et une faible expression de HER-2 dans le cancer colorectal en utilisant l'immunohistochimie, suggérant un rôle possible de COX-2 dans la pathogenèse du CCR. Ce rapport devrait déclencher des investigations plus poussées des deux marqueurs vis-à-vis de la gestion du CRC dans notre environnement.

Mismatch Repair Protein Expressions in Cohort of Colorectal Carcinoma Patients in Lagos.

BACKGROUND: Colorectal carcinoma (CRC) is a major cause of morbidity and mortality worldwide. Microsatellite instability pathway is important in the pathogenesis of CRC. Immunohistochemistry expression of mismatch repair (MMR) proteins serves as surrogate marker for MMR gene mutation. AIMS: This study aimed to determine MSI status of a cohort of CRC cases using immunohistochemistry. MATERIALS AND METHOD: Surgical pathology blocks of resected colonic carcinoma (CC) between 2011 and 2015 were extracted from our departmental archives and The Specialist Laboratories in Lagos. Immunohistochemical expression profile of 4 MMR proteins was assessed in the representative blocks and this was correlated with the demographic and pathological characteristics. RESULTS: There were 19 males and 16 females with CC, mean age of 51.6 years, and 40% of them were below 50 years of age. Twenty (57.1%) out of the 35 CC cases seen were mismatch repair proficient (pMMR) while the remaining 15 (42.9%) were mismatch repair deficient (dMMR). Seven dMMR cases were seen equally on the right and left colonic tumors respectively. Five (71.4%) out of the 7 mucinous tumors in this study were dMMR, right sided with 3 of them in patients who were below 50 years of age. CONCLUSION: The frequency of mismatch repair deficiency in CC among Nigerians is high, and presence of right-sided mucinous colon cancer in patients below 50 years is highly suggestive of dMMR status. Mutation studies of larger patient samples to determine the percentage with germline mutation will further our knowledge, and influence therapeutic options for CC.

Autopsy Study of the Liver in Adult Nigerians at Lagos University Teaching Hospital.

BACKGROUND: Liver diseases are one of the major causes of morbidity and mortality in Nigeria. Detection of liver involvement in many disease conditions is often delayed till after death when autopsy is conducted, hence the importance of this study. STUDY DESIGN AND METHOD: This was a prospective study to assess the pathologic findings in the liver of one hundred (100) consecutive adults (without pre-mortem diagnosis of liver disease) at autopsy, at the Lagos University Teaching Hospital (LUTH), Lagos, Nigeria. The organs were examined macroscopically, weighed and representative biopsies taken for histopathological assessment. Special histochemical stains to confirm diagnosis were carried out as appropriate. The biodata and other clinical information were obtained from the case notes. Analysis was carried using descriptive statistics. RESULTS: One hundred cases were studied, comprising of 46 males and 54 females, with overall mean age 47±15.6 years. The mean weight of the liver was 1737±586.02 grams (normal 1200-1400gm). In 19.0% of the cases, the liver showed normal histology. Of the others with pathological findings (81%), the three most common pathologies were chronic venous congestion, steatosis, and metastatic tumours. There was significant correlation of liver pathologies diagnosed with causes of death at autopsy (p=0.001). CONCLUSION: In view of the fact that major liver diseases may be asymptomatic and may not be diagnosed until death, there is need for a high index of suspicion by clinicians. It is therefore important that clinicians properly assess the functional state of the liver to prevent, detect and promptly treat these disorders.