Histopathology (also called surgical or anatomic pathology) is a vital diagnostic tool for studying and identifying tissue changes in a disease under the microscope. The physician may choose to take a small piece of tissue from the disease site or organ (incision biopsy) or may send the whole lesion or organ for histopathological examination (excision biopsy). It is mandatory that any tissue removed from a human body is submitted for histopathological examination.

One the major roles of histopathologists are in the diagnosis and precise categorisation of neoplastic disorders (like various types of cancers).

The Histopathology lab of Aga Khan University Hospital is divided into various sub-sections, i.e., surgical pathology, cytopathology, special pathology, flow cytometry, cytogenetics and semen analysis. The lab is well-equipped with state-of-the-art equipment and is currently run by 11 full-time faculty members and a staff of 44.

It is a major referral centre for all over Pakistan and Afghanistan, and it receives approximately 40,000 surgical biopsy specimens and 18,000 cytology specimens per year. The Section also participates in various external quality control programmes.

Pathology is a bridge between basic and clinical sciences. The role of our Section in undergraduate teaching is immense. The current curricular chair as well as several modular chairs are from this Section.

The Section is also fully credentialed for Histopathology residency by CPSP. Currently 14 residents are undergoing training. The Section also participates actively in the Technologists Training Programme.

The Section is very active in research, particularly in the area of cancer. Major cancers of interest are breast, lymphoma and oral cancers. Basic cancer research includes viral carcinogenesis while clinical interest is mainly in novel prognostic markers. The Section also maintains a pathology-based cancer registry recognised by IARC/WHO and is also a major contributor to the only population-based cancer registry in Pakistan, i.e., Karachi South Cancer Registry. In 2007, 24 publications originated from the Section, half of which were in international peer-reviewed journals.