Cellular pathology

The Department of Cellular Pathology comprises of two specialties - Histology and Cytology

Annually, the department receives more than 22,000 surgical histology samples and 6,000 non-gynaecological cytology samples. In addition, cytology  provides a  cervical screening service for women living in Brent, Harrow and Hillingdon and analyses 60,000 samples a year.

The department has more than 60 members of staff  that includes pathologists, biomedical scientists, cytoscreeners, medical laboratory assistants, medical secretaries and clerical staff.

The Department is also the base for the London Regional Cytology Training Centre - providing all the courses and training for cytologists within the London region and beyond.

Description of service

Histology is the investigation and diagnosis of disease from the microscopic examination of tissues.
Tissue taken during surgery or at post-mortem is put into a preservative solution and processed, enabling it to be embedded in wax. The tissue can then be cut into very thin slices, stained with dyes and studied under the microscope looking for cellular abnormalities such as cancer.

Cytology is the investigation and diagnosis of disease from the microscopic examination of isolated cells. Cytology studies the cells that can be scraped from the surfaces of tissues or the cells found naturally in fluids from anywhere in the body. These are sent for processing in the laboratory where these cells can then be transferred onto a glass slide, stained with various dyes and examined under the microscope.

Histology investigations include:

  • Biopsies, or small pieces of tissue, removed at the GP surgery or in one of the specialist clinics.
  • Larger pieces of tissues or part of organs removed during surgery
  • Post-mortem specimens examined at autopsy   

Cytology investigations include:

  • Cervical smears or samples received as part of the Cervical Screening Programme     
  • Andrology, or sperm tests, as part of infertility investigations
  • Diagnostic samples including pleural (lung) fluid, ascitic or peritoneal (abdominal) fluid, synovial (joint) fluid, respiratory samples such as sputum, and urine.
  • FNA samples or Fine Needle Aspirates obtained when a clinician uses a small needle to sample a few cells from a lump anywhere on the body, such as from the neck or breast.


Northwick Park and St Mark's Hospitals

Patients delivering samples for testing are requested to go to the drop-off point at Pathology Reception, Level 5 (Block 5C) of Northwick Park Hospital.

Central Middlesex Hospital

Samples taken or received at Central Middlesex Hospital are transported by the Hospital courier system to Northwick Park Hospital for processing and reporting.


Northwick Park and St Mark's Hospitals

  • Enquiries
    020 8869 3309 8.30 to 17.30 Mon to Fri

Consultants and other key staff

View Cellular pathology consultants »