A morphological and immunohistochemical evaluation of gastric carcinoma in the Western Cape province of South Africa

  • Riyaadh Roberts University of Cape Town and National Health Laboratory Service
  • Padmini Govender University of Cape Town
  • Richard Naidoo University of Cape Town and National Health Laboratory Service
  • Michael Louis Locketz University of Cape Town and National Health Laboratory Service
Keywords: Gastric carcinoma, young cancer, E-cadherin, Her2/neu, Western Cape

Abstract

Background: Gastric resections for carcinoma are common, but gastric carcinoma in South Africa, and particularly within the Western Cape province, has not been well documented.

Method: The objective of the study was to immunohistochemically evaluate HER2/ neu overexpression, determine aberrations in β-catenin and epithelial-cadherin (E-cadherin) expression, and correlate these findings with gastric carcinoma subtypes.

Results: Ninety-seven gastric adenocarcinoma resections were morphologically categorised as intestinal-, diffuse- or mixed-type adenocarcinomas, and immunohistochemically stained for β-catenin, E-cadherin (extracellular and cytoplasmic domains) and HER2/neu. The results of staining were compared between the subtypes for statistically significant differences. All 97 cases were confirmed as gastric adenocarcinomas, with 39 (40%) intestinal- type, 51 (53%) diffuse-type, and 7 (7%) mixed-type tumours identified. Patient ages ranged from 18–4 years. HER2/neu was overexpressed in 12 (12%) cases, with intestinal-type morphology (p = 0.017) reported in nine. Fourteen cases (14%) demonstrated abnormal β-catenin localisation. Aberrant E-cadherin (extracellular domain) localisation occurred in 36 (37%) cases. Diffuse-type morphology was associated with a significantly high proportion (p = ≤0.001). Aberrant E-cadherin (cytoplasmic domain) localisation occurred in 7 (7%) cases. A significantly high proportion (six of these cases) (p = 0.023) of these was diffuse-type morphology. Eleven (11%) adenocarcinomas occurred in patients aged ≤40 years, with intestinal morphology reported in nine of these 11. Aberrant E-cadherin (extracellular domain) localisation was noted in seven of the 11, a significantly high proportion when compared to that in the older patients (p = 0.025).

Conclusion: Distinct immunomorphological correlations are apparent in tumours demonstrating HER2/neu overexpression or abnormal E-cadherin localisation. Intestinal morphology, poor differentiation and E-cadherin abnormalities are frequently demonstrated in tumours occurring in younger individuals.

Author Biographies

Riyaadh Roberts, University of Cape Town and National Health Laboratory Service

MBChB (UCT), FCPath(SA)Anat, MMed (UCT)

Division of Anatomical Pathology
University of Cape Town and
National Health Laboratory Service

Groote Schuur Hospital

Padmini Govender, University of Cape Town

ND (Med Tech), BTech, MMedSci

Division of Anatomical Pathology
Faculty of Health Sciences
University of Cape Town
Cape Town
South Africa

Richard Naidoo, University of Cape Town and National Health Laboratory Service

BSc, BSc(Hons), MMedSci, PhD

Division of Anatomical Pathology
University of Cape Town and
National Health Laboratory Service
Groote Schuur Hospital

Michael Louis Locketz, University of Cape Town and National Health Laboratory Service

MBChB, MMed, FCPath(SA)Anat

Division of Anatomical Pathology
University of Cape Town and
National Health Laboratory Service
Groote Schuur Hospital

Published
2016-05-04
How to Cite
Roberts, R., Govender, P., Naidoo, R., & Locketz, M. (2016). A morphological and immunohistochemical evaluation of gastric carcinoma in the Western Cape province of South Africa. South African Journal of Surgery, 54(1), 15-21. Retrieved from http://sajs.redbricklibrary.com/index.php/sajs/article/view/1903
Section
Original Articles