A report from Dr Mohamed Elshiekh on his visit to the Mayo Clinic

It was during the final few months of my training at St Thomas’ Hospital in London, when I thought about visiting a world-renowned institution in the USA to see how cytopathology practice and training there differed to what I had experienced in the UK. 

I discussed this with my educational supervisor, Dr Ashish Chandra, whose advice and support were instrumental in arranging a three week visit to Mayo Clinic’s cytopathology department in August 2023.

Mayo Clinic is top-ranked in more specialties than any other hospital in the USA according to U.S. News & World Report's 2023-2024 "Best Hospitals" rankings. The cytopathology laboratory, which is part of Mayo’s Division of Anatomic Pathology, receives over 55,000 specimens a year including FNA, GYN and non-GYN cytology, in addition to FISH analysis for urine and biliary specimens.

I spent my time with the cytopathology fellows and consultants. 

There was a dedicated sign out area where the fellow would preview cases and then consultants would join them at the multiheaded microscope to report. The daily caseload was divided into (1) FNA and (2) Fluids assigned to two different consultants. All cases were screened by cytotechnologists who would mark the slides and record their impression. 

The cases were then previewed by the fellow and relevant clinical information was retrieved from the electronic patient record to be ready for discussion with the consultant during the reporting session. Consultants preferred brief reports with little microscopic descriptions unless the case was difficult. The cytopathology fellow covering the FNA caseload would alternate daily, providing preliminary diagnosis on one day and working on follow-ups the following day.

The majority of FNA specimens were touch imprints of core biopsies performed by clinicians/radiologists. This allowed a rapid assessment to be performed and a preliminary report given to the clinician within a few hours of the biopsy. 

Immunohistochemical stains would also be requested for the core biopsy based on the initial assessment of the touch imprint, significantly reducing turnaround times. This practice also allowed continuous cytological and histological correlation which is very important for teaching and training. 

Other specimens included in the FNA caseload included thyroid FNAs which were performed by endocrinologists or radiologists depending on the size of the lesion. Cytopathology fellows were encouraged to attend the thyroid FNA clinic, and were trained on how to perform FNAs. 

Most of the slides were Pap stained which I personally found particularly challenging for thyroid cases, in which assessment of colloid is more feasible on MGG stained slides. Occasionally, MGG slides were prepared when a cytotechnologist performed ROSE to assess for adequacy in EUS and EBUS-guided clinics.

The fluids caseload included pleural, ascitic and pericardial fluids as well as urine and endoscopic washings/brushings. 

A ThinPrep slide was prepared for these specimen types, and occasionally an MGG stained cytospin slide was also available for cases requiring inflammatory cell counts. The fellow covering the fluids caseload attended regular didactic teaching sessions delivered by the cytotechnology school which covered the cytopathology curriculum, and many slide sets were available for review. 

There is no national cervical cancer screening programme in the US and depending on clinician request, cervical smears had HPV testing and/or cytology, although it was more common to have both performed.

I thoroughly enjoyed the time I spent at Mayo Clinic and this was a great opportunity to see how the cytopathology service is delivered in one of the world’s most advanced hospitals. The service is very efficient and turnaround times of 24-48 hrs were standard. 

The lab and medical staff are enabled to achieve this with the help of a team of admin staff who ensured ancillary studies were requested and returned to the fellow/consultant in a timely manner.

Founded in the 1880s, the Mayo Clinic campus in Rochester, Minnesota, includes 30 buildings including the historic landmark Plummer building to the more modern state of the art Gonda building with its valet entrance and marble-filled lobby catering to visitors from all over the world. I visited the Mayo Clinic Heritage Hall and toured the historical 3rd floor suite in the Plummer building which contained artifacts from the founders of Mayo Clinic, Drs Will and Charlie Mayo.