Hormonal and Growth Receptor Expression as Targets for Therapy in Esophageal Squamous Cell Carcinoma Patients of Pakistan

Authors
Dr Syed Muhammad Adnan Ali, Dr Yumna Adnan

Affiliations
Department of Surgery, Medical College, The Aga Khan University, Pakistan

Introduction
Esophageal cancer is one of the deadliest cancers in the world, with approximately 0.5 million deaths occurring in the year 2020 alone. Pakistan has an age-standardized incidence of 4.1 per 100,000 for esophageal cancer. The most common form of esophageal cancer is esophageal squamous cell carcinoma (ESCC), and despite advances in surgery and other treatments, patients suffer from a poor prognosis. Hormonal receptors such as AR, ER and PR and growth receptor Her-2 have strong therapeutic implications for other cancers. This study investigated the role of these markers in ESCC patients of Pakistan to determine the relationship between their expression and patient characteristics.

Methods
A total of 116 patients diagnosed and/or surgically treated for ESCC at Aga Khan University Hospital (AKUH), Karachi, Pakistan were included. Patients represented all provinces and major cities of Pakistan, including Balochistan, the province lying within the Asian esophageal cancer belt. The expression of biomarkers Her-2, AR, ER and PR was determined via immunohistochemistry using the following primary antibodies from Dako: mouse monoclonal PgR 636 for PR, rabbit monoclonal EP1 for ERα, mouse monoclonal AR441 for AR and rabbit polyclonal A0485 for Her-2 in combination with the EnVision System for staining visualization.

Results
The majority of patients, 65%, were males while 35% were females. The most common histological subtype was moderately differentiated ESCC. The biomarkers tested were positively expressed in as follows: 47% for Her-2, 30% for AR, 44% for ER and 30% for PR. The positive expression of Her-2 was associated with statistically significant higher T stage (P=0.037) and increasing N stage (P=0.04). AR and ER were most often found to be expressed together (P=0.025). PR was not significantly associated with any of the parameters tested.

Conclusion
Her-2 may be a promising target for therapy in ESCC and further studies are warranted for its clinical application.