Israh Akhtar, MD, Kamal Khurana, MD, Roxanne Florence, MD
In many institutions, there is an increasing incidence of needle core biopsy for the purposes of diagnosis or acquisition of material for molecular testing or clinical trials. Cytology attendance for Rapid Onsite Evaluation (ROSE) of the touch preparation often accompanies or even replaces fine needle aspiration (FNA). Advances in molecular diagnostics, increasing clinical trial enrollment and more sophisticated imaging modalities have greatly increased the number of these diagnostic procedures. With the burgeoning role of personalized medicine, the demand for ancillary testing on smaller biopsy specimens is greater than before. Needle core biopsies (NCB) have proven to be an excellent source of tissue for molecular testing, yielding sufficient material for testing via a relatively minimally invasive technique.1
Cytologists play an important role in the use of minimally invasive techniques for personalized medicine-based therapeutics. They are well versed in ROSE on FNA for the adequacy and triage of tissue for diagnosis and requisite ancillary studies. As NCB with touch imprint ROSE has become a more common method for obtaining tissue, cytologists have become increasingly experienced with this methodology. Concurrently many institutions have moved toward subspecialty histopathologic sign-out. These changes have resulted in a metaphorical tug of war as to where the final specimen should best be assigned. In short: should core biopsies with associated touch preparations be assigned to the cytology service, the surgical pathology service, or split between the two?
According to a 2015 CAP non-gynecologic survey, more than half of the laboratories that responded performed ROSE on touch imprints of NCB. On-site assessment of the touch imprints were performed by a surgical pathologist in 81.1% and by a cytopathologist in 57.2% of the laboratories surveyed.2 The majority of laboratories accessioned both touch imprint and NCB as a surgical specimen (54.4 %), followed by accessioning the entire case as a cytology specimen (28.4 %) and least often, splitting the case between cytology and surgical pathology (15.5%).2
Each of these routes may have benefits and disadvantages for a variety of reasons including: patient care, trainee education, laboratory and pathologist workflow, and RVU distribution among services (Table 1), among others. Herein, three cytopathology program directors discuss the advantages and disadvantages of the different approaches their institutions have taken, with an emphasis on the impact upon trainees.
I. Both NCB and TP assigned to subspecialty surgical pathology (Israh Akhtar, MD)
It is not unusual for both the needle core biopsy and touch imprints to be sent together to a subspecialty surgical pathologist for final sign-out. In fact, this is the most common practice nationwide2. Having said this, how does this impact cytopathology fellowship training?
Interpreting touch imprints differs from interpreting FNA smears and involves a relatively steep learning curve.3, 4 Cytopathology is a complex, varied and specialized field in which many practitioners undergo one year of fellowship training followed by board certification, leading to a higher level of familiarity and expertise in examining such specimens. As a result, surgical pathologists without this additional year of dedicated training may not feel quite as comfortable or be as diagnostically accurate, as their fellowship trained counterparts. Positives and negatives to keeping the case together in surgical pathology include:
- Having the complete case with subspecialty surgical pathologist permits one person to render a specific diagnosis and decide on appropriate ancillary testing to be performed, when applicable.
- The cytopathology fellow may need to go out of their way to make sure they are involved with the case from acquisition of sample to final sign-out. If the core biopsy is in surgical pathology, the cytopathology fellow will need to track down the core biopsy slide in order to correlate the cytologic features on touch prep with the needle core biopsy sample. However, this will also give them exposure to complex surgical pathology subspecialties. This is especially true in the instance of soft tissue/bone or hematopathology cases; where cytogenetics, molecular testing, flow cytometry etc. play a major role in diagnosis, with ever evolving classifications and even more complex molecular profiles.
- If the fellow is not able to see the core biopsy slide, they lose the aforementioned learning opportunities.
- Another observed trend includes pathology subspecialists making a diagnosis based only on the needle core biopsy and ignoring touch imprints/FNA smears, due to lack of comfort or experience in interpreting cytology. Furthermore, even with expertise in cytology, if the surgical pathologist has not performed the ROSE, he/she may not have all the relevant clinical and radiologic information while signing out the case.
- If directly routed to surgical pathologists, cytotechnologist screening would be bypassed. In up to 49.7% centers, the cytotechs play an active part in ROSE.2 If circumvented entirely, they lose an opportunity to continue to sharpen their skills in preliminary screening of non-gynecologic slides.
- The benefit to patient care includes the subspecialist up-to-date knowledge on ancillary/molecular testing required for diagnosis and further management and potentially better cytologic-histologic correlation, as discordant results can be easily picked-up (provided the surgical pathologist has an adequate level of comfort in cytology diagnosis).
- Although the overall RVUs should stay the same, they would be redistributed to surgical pathology and away from cytopathology.
In summary, disposition of touch preps and the histologic slides to the surgical pathology service may enhance patient care in certain ways (and perhaps worsen it in others), but may hamper fellow education, preclude cytotech involvement, and reduce overall compensation of cytopathology section in the form of decreased relative value units (RVUs).
II. Both NCB and TP assigned to cytology (Roxanne Florence, MD)
Accessioning both ROSE touch preps and their corresponding core biopsies to the cytology service has many advantages, including optimizing trainee education and patient care and preventing duplication of ancillary testing. Disadvantages also exist. Both are elaborated below:
- The cytology team can view the advancement of the core needle into the lesion, and judge for themselves whether the target has been sampled. Additionally, they can obtain the interventionalist’s perspective on the likelihood that the target was hit, and diagnostic possibilities. The radiologist may relate further thoughts or history that are not on the requisition. All of this information may not transfer if the case is accessioned to surgical pathology, and saves the time necessary to convey all of these details.
- The ROSE team often requests additional specimen be collected for flow cytometry, microbiology, etc. Ancillary specimens/testing, which are in process may not be realized or readily available to the surgical pathologist to whom the case has been assigned.
- Selecting which specimen (core vs. FNA cell block) is most appropriate (least necrotic, largest volume of tumor) for an immunohistochemical work up or molecular testing is fastest and easiest if one person (preferably the cytopathologist) has both specimens. It also eliminates the possibility of duplicate ordering on both specimens from the cytopathologist and surgical pathologist.
- Keeping a core with touch preps in the cytology department eliminates the possibility of discrepant final diagnoses between the core and any corresponding FNA (rapid and critical cytologic-histologic correlation), which can occur if there is a lack of communication between two pathologists.
- The ROSE cytology fellow and the cytopathologist have guaranteed feedback/learning opportunities on their immediate interpretations.
- Accessioning may be simpler and sign-out faster if all materials from the procedure are assigned to one (cyto)pathologist.
- A disadvantage and the strongest argument for accessioning core cases evaluated with ROSE to surgical pathology may be that some cytopathologists lack depth of knowledge and about certain tumor types seen on core biopsy. This will vary by department and individual. If the core and touch preps are initially sent to cytology, the team can quickly review them to gain feedback and then if necessary either seek a formal second opinion from an appropriate surgical pathology subspecialist or give them the case entirely.
In summary, trainee education, ROSE performance feedback, patient safety and cost are optimized when both needle core biopsies and their corresponding touch preps are assigned to the cytology service.
III. TP assigned to cytology and NCB assigned to surgical pathology (Kamal Khurana, MD)
As per the 2015 CAP non-gynecological survey, accessioning touch imprints as a cytology specimen and needle core biopsy as a surgical specimen is an uncommon practice (15.6%),2 but is not without merit. The workflow is: ROSE is performed by the cytology fellow cytotechnologist, and/or cytopathology attending. This allows the attending to include feedback regarding the fellow’s interpretation of touch imprints, recommend ancillary culture, flow cytometry or obtaining more tissue for molecular testing. If the touch imprint is not adequate, additional cores are requested. The touch imprint is signed out by the cytology service. The core needle biopsy is handled by the surgical pathology service. Each service issues a separate report, and references the other. The patient history and touch imprint assessment are made available to surgical pathologists. The cytopathology fellow tracks the surgical core needle biopsy for cytologic-histologic correlation. If there is a discrepancy between on-site assessment and the final diagnosis, the cytopathology service is contacted for resolution.
Advantages and disadvantages include:
- Assigning a needle core biopsy to the surgical pathology section allows the case to be signed-out by an expert subspecialist.
- Touch imprints are signed out by cytopathology because most of the surgical pathologists are more comfortable making a diagnosis on core needle biopsies and/or do not find touch imprints useful in arriving at the final diagnosis. Meanwhile the cytopathologist can review the touch imprint and teach the cytomorphologic findings to the fellow.
- Communication between the surgical pathology and cytopathology teams is important to yield a unified diagnosis.
- This practice, of handling core needle biopsy by surgical pathology, allows residents rotating through surgical pathology service to get maximum exposure working-up small biopsy specimens since in some institutes the cytopathology service is not always staffed with residents.
- Keeping track of surgical core needle biopsy for cytologic-histologic correlation may require additional time and effort, but it benefits the fellow’s training, as the fellow learns about the core biopsy from the subspecialist.
In summary, the system of keeping the touch prep for cytopathology service and core needle biopsy for surgical pathology can also work well. The cytopathology service ensures that an optimal specimen is collected and can sign out the final cytology, whereas the surgical pathology service allows for optimal diagnosis using the acumen of our expert surgical pathologists.
The “need to do more with less” in the era of targeted therapy/personalized medicine has resulted in an increasing preference in many institutions for needle core biopsy with ROSE on a touch imprint. It is important that cytopathologists and cytopathology program directors as a group recognize this paradigm shift and ensure themselves a seat at the table in decisions on the best handling and disposition of these specimens (Table 2). A part of doing this is reviewing the literature and weighing the benefits and weaknesses of all the available methods of handling specimens, some of which have been discussed in this article; so as to best serve patients care and optimize trainee education.
- Aisner DL, Sams SB: The role of cytology specimens in molecular testing of solid tumors: techniques, limitations, and opportunities. Diagn Cytopathol 2012;40:511-524.
- Padmanabhan V, Barkan G, Nayar R: Cytopathology and more: assessing needle core biopsy adequacy – survey of practices. CAP TODAY 2016; May
- Gupta NJ, Wang HH. Increase of core biopsies in visceral organs—experience at one institution. Diagn Cytopathol. 2011;39(11):791–795.
- Hahn P, Eisenberg PJ, Pitman MB, Gazelle GS, Mueller PR. Cytopathologic touch preparations (imprints) from core needle biopsies: accuracy compared with that of fine-needle aspirates. AJR Am J Roentgenol. 1995;165(5):1277–1279