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Dermatopathology laboratory

Tests and investigations for general and specialist dermatopathology 


Coronavirus: dermatology update

In response to the coronavirus (COVID-19) outbreak, please read our advice and information before attending the service.


  • General or urgent enquiries:

    Dermatopathology laboratory
    St John's Institute of Dermatology
    2nd floor, South Wing, Staircase C
    St Thomas' Hospital
    Westminster Bridge Road
    London SE1 7EH

  • Tel: 020 7188 6408

    Fax: 020 7188 6382

Enquiries concerning reports: secretaries office, 020 7188 6408.

Enquiries relating to tests: Dr Guy Orchard, 020 7188 8160 or email

Specific guidance on dispatching/sending tissue samples: Dr Guy Orchard, 020 7188 8160 or email

Interpretation of results: Dr Eduardo Calonje (head of department), 020 7188 6408 or email

About the dermatopathology laboratory

Our dermatopathology laboratory is the largest dedicated skin pathology centre in the UK, with vast experience in complex and rare cases.

We are a major referral centre for both general and specialist dermatopathology. More than 14,000 cases a year are processed by the laboratory and reviewed by specialist consultant dermatopathologists.

We provide support for the Mohs micrographic surgery unit, which involves the removal of facial skin cancer. The Mohs unit is now one of the largest units within the UK for this service.

We have a growing reputation in the study of lymphoma and melanoma, and offers extensive laboratory tests and investigations in these areas.

  • Opening times

    The routine laboratory opening times are from 9am to 5.15 pm, Monday to Friday.

    There is no formal weekend working or after hours working arrangements.

    Routine specimens should not be delivered for processing after 4pm on any given day.

  • Speciman requirements

    All specimens sent to the department should be accompanied by appropriate documentation (histology request form or referring letter), and meeting all of the acceptance criteria.

    This is documented on the Viapath website.

    High risk specimens should be marked accordingly on both the request form and specimen pot. Specimens received for processing should be fixed in 10% neutral buffered formalin in an appropriate volume which covers the specimen. Standard 60ml pots with formalin can be provided upon request.

    In order to minimise the risk of specimen interchange, please make sure specimens are appropriately labelled and segregated to distinguish between different patients.

    Make sure all patient demographics and full clinical information is clearly stated on the request form.

    If there are any additional requirements, for example stitch markers to indicate orientation or in the case of small friable tissue samples, that they are wrapped to conserve fragments. Please make sure these requirements are clearly stated on all correspondance.

    The transfer of specimens from the clinical areas to the laboratory should be done within 24 hours ideally. In cases of delays or errors the laboratory should be informed immediately. Error logs should be completed from the sender's and receiver's end accordingly. Where serious errors have been identified and which influence patient care then a Datix or incident reporting form will be completed by the laboratory.

  • Health and safety

    All specimens sent should be packaged safely according to postal guidelines, which can be found on the Viapath website.

    If required, formalin should be disposed of in a safe manner ie down the sink with the use of copious volumes of water. However, if there is a significant spillage ie 500ml or more, staff should evacuate and contact the fire brigade. In case of lower volumes a formalin spill kit is recommended.

    All sharps should be disposed of in a safe manner which employs the use of a sharps clinical waste bin.

  • Additional requests

    If any specimen requires additional investigations - for example immunocytochemistry - then this should be clearly stated on the request form with any specfic turn around time requirements.

    In addition where follow up investigations are required, then this needs to be clear on any additional requests. Further, if such requests are made after routine processing then the laboratory needs to be informed directly and specific arrangements made.

  • Referrals

    Please send your referral letter to the address at the top of this webpage, along with a completed histopathology request form outlining the patient information, clinical history and type of specimen (block or slide).

    Dermatopathological referrals are accepted from within Guy's and St Thomas', from consultants and hospitals (both NHS and private) and from overseas.

    If the referral is urgent please mark the letter accordingly and ensure contact details are provided.

  • Results

    We aim to provide a written report for diagnostic purposes within three to five working days of specimen receipt. If further immunocytochemical tests are required, a further five days may be necessary to complete the process. Turn around times for reports on referral cases is set at a maximum of three weeks or 15 working days.

    Results are available to clinicians by telephone on 020 7188 6408 or by fax on 020 7188 6382. 

    No information will be given to patients or their relatives.

  • Cost

    Please contact the laboratory directly to discuss tests required and charges.

  • Staff


    • Dr Eduardo Calonje – clinical head of department and consultant dermatopathologist
    • Dr Catherine M. Stefanato MD – consultant dermatopathologist
    • Dr Kristina Semkova – consultant dermatopathologist
    • Dr Eglantine Lebas – consultant dermatopathologist
    • Dr Anoud Zidan – consultant dermatopathologist

    Laboratory Staff:

    • Dr Guy Orchard – head of laboratory
    • Patricia Fernando – senior biomedical scientist

    • Theddeus Nwokie – senior biomedical scientist

    • Fiona Ismail – senior biomedical scientist

    • Jose Satoc – senior biomedical scientist

    • Mohammed Shams – senior biomedical scientist

    • Peter Sounthararajah – biomedical scientist

    • Karolina Wojcik - biomedical scientist

    • Jeyrroy Gabriel – biomedical scientist

    • Pushpaharan Balachandran – biomedical scientist

    • Zainab Ramji – associate practitioner
    • Rasiyan Salih – associate practitioner
    • Uchini Kosgodage – associate practitioner
    • Anna Georgaki – medical laboratory assistant
    • Dionne Kirk – medical laboratory assistant
    • Mariam Mohammad – medical laboratory assistant
    • Khaled AbuSalem – medical laboratory assistant
    • Abiye LeeMeheux – medical laboratory assistant

    Administrative staff:

    • Nick Easterbrooke – office manager
    • John Gutierrez
    • Adam Pugh
    • Wendy Embleton
    • Catriona Ritchie

Questions about sending samples?

For more information about sending samples, visit the Viapath website (our pathology services provider).