Assessment of Quality of Frozen Section Services at a Large Academic Hospital Before and After Relocation

OBJECTIVES

To determine outcomes following relocation of frozen section services (FSS) and the implementation of a dedicated gastrointestinal frozen service.

METHODS

We reviewed our FSS 6 months prior to and following FSS relocation. Satisfaction surveys were sent to surgeons and pathologists. Survey feedback resulted in a pilot of gastrointestinal subspecialist frozen section coverage.

RESULTS

There were 1,607 and 1,472 specimens from 667 and 602 patients pre- and post-FSS relocation, respectively. There was a decline in median specimen delivery time to pathology (12 vs 10 minutes, P < .001) and an increase in median time from receipt in pathology to intraoperative diagnosis (20 vs 22 minutes, P = .008) in cases with intrapathology consultation but no change without consultation (median, 19 minutes). Intrapathology consultation decreased from 19.7% (317/1,607) to 11.5% (169/1,472) (P < .001). Discordance rates between frozen section and permanent section remained low and similar (2.0% [33/1,607] vs 2.7% [40/1,472], P = .24). There was no significant change in discordance with dedicated gastrointestinal subspecialty frozen section interpretation.

CONCLUSIONS

Relocation of FSS and dedicated subspecialty interpretation may improve surgeon satisfaction but can also create workflow challenges. Pathology departments need to achieve a balance between satisfaction and adequacy to establish best frozen section coverage models.

A retrospective analysis of the diagnostic accuracy and technical quality of frozen sections in detecting hepatobiliary lesions

INTRODUCTION

Pathological consultation on intraoperative frozen sections plays a crucial role in the management of patients undergoing surgical therapy, and is also a key indicator for quality assurance in anatomical pathology. This study aimed to evaluate the diagnostic accuracy and technical quality of frozen sections in detecting hepatobiliary lesions with malignant potential.

PATIENTS AND METHODS

A retrospective database review was performed for 1208 cases intraoperative pathology consultation who underwent hepatobiliary lesions resection at our institution from 2016 to 2020. The intraoperative consultation cases during a 5-year period were reviewed and analyzed, including the measurement of the diagnostic accuracy and turnaround time of frozen sections, the reasons for discrepancies, and the rates of discordance and deferral.

RESULTS

In this study, we confirmed that the overall accuracy, sensitivity and specificity were 95.3 %, 96.3 % and 96.6 %, respectively, in distinguishing benign from malignant lesions. The rates of deferred and discordant diagnoses were 2.57 % and 2.2 %, respectively. The overall frozen section turnaround time was 22.1 min. The most common cause of deferred and discordant was poor section quality, the lesion of bile duct margin on the frozen section, misinterpretation of difficult and complicated cases, etc. CONCLUSIONS: This study confirms that the intraoperative frozen sections can serve as a rapid, accurate and robust method for the pathological diagnosis of suspected hepatobiliary lesions. However, it should be noted that some poor technical problems, pathological assessment of tumor margin and difficult cases are the most frequently causes of deferred and discordant interpretations.

Utility of frozen section in pediatric and adolescent malignant ovarian nonseminomatous germ cell tumors: A report from the children's oncology group

PURPOSE

In adult women, most malignant ovarian tumors are epithelial in origin. The use of intra-operative frozen section to distinguish between benign and malignant histology is reliable in guiding operative decision-making to determine the extent of surgical staging required. Pediatric and adolescent patients with ovarian masses have a much different spectrum of pathology with most tumors arising from germ cell precursors. This review was undertaken to assess the concordance between the intra-operative frozen section and the final diagnosis as an aid to guide extent of surgical staging in a group of pediatric and adolescent patients with malignant ovarian germ cell tumors.

METHODS

Records of patients aged 0 to 20 years with malignant ovarian germ cell tumors enrolled on Children's Oncology Group study AGCT0132 were reviewed. Pathology reports from patients who had both intra-operative frozen section diagnosis and final paraffin section diagnosis were compared using descriptive statistics. By inclusion criteria for the study, all patients had a final diagnosis of malignancy with required yolk sac tumor, choriocarcinoma or embryonal carcinoma histology. Available central review of pathology final paraffin section slides were compared with final institution pathology reports.

RESULTS

Of 131 eligible patients with ovarian germ cell tumors, 60 (45.8%) had both intra-operative frozen section and final paraffin section diagnoses available. Intra-operative frozen section diagnoses were classified as: incorrect diagnosis of benign tumor (13.3%), confirmation of malignancy (61.7%), immature teratoma (16.7%), germ cell tumor not otherwise specified (5%) and no diagnosis provided (3.3%). Intra-operative frozen section was incorrect in 23 of 60 (38.3%) patients evaluated. Central pathology review was concordant with the final institution pathology diagnosis in 76.3% of patients. Central pathology review identified additional germ cell tumor components in 23.7% of patients.

CONCLUSIONS

In pediatric and adolescent patients with a confirmed final diagnosis of ovarian germ cell malignancy, intra-operative frozen section diagnosis is not reliable to inform the extent of surgical staging required. Central review by an expert germ cell tumor pathologist provides important additional information to guide therapy.

NeuroSAFE PROOF: study protocol for a single-blinded, IDEAL stage 3, multi-centre, randomised controlled trial of NeuroSAFE robotic-assisted radical prostatectomy versus standard robotic-assisted radical prostatectomy in men with localized prostate cancer

BACKGROUND

Robotic radical prostatectomy (RARP) is a first-line curative treatment option for localized prostate cancer. Postoperative erectile dysfunction and urinary incontinence are common associated adverse side effects that can negatively impact patients' quality of life. Preserving the lateral neurovascular bundles (NS) during RARP improves functional outcomes. However, selecting men for NS may be difficult when there is concern about incurring in positive surgical margin (PSM) which in turn risks adverse oncological outcomes. The NeuroSAFE technique (intra-operative frozen section examination of the neurovascular structure adjacent prostate margin) can provide real-time pathological consult to promote optimal NS whilst avoiding PSM.

METHODS

NeuroSAFE PROOF is a single-blinded, multi-centre, randomised controlled trial (RCT) in which men are randomly allocated 1:1 to either NeuroSAFE RARP or standard RARP. Men electing for RARP as primary treatment, who are continent and have good baseline erectile function (EF), defined by International Index of Erectile Function (IIEF-5) score > 21, are eligible. NS in the intervention arm is guided by the NeuroSAFE technique. NS in the standard arm is based on standard of care, i.e. a pre-operative image-based planning meeting, patient-specific clinical information, and digital rectal examination. The primary outcome is assessment of EF at 12 months. The primary endpoint is the proportion of men who achieve IIEF-5 score ≥ 21. A sample size of 404 was calculated to give a power of 90% to detect a difference of 14% between groups based on a feasibility study. Oncological outcomes are continuously monitored by an independent Data Monitoring Committee. Key secondary outcomes include urinary continence at 3 months assessed by the international consultation on incontinence questionnaire, rate of biochemical recurrence, EF recovery at 24 months, and difference in quality of life.

DISCUSSION

NeuroSAFE PROOF is the first RCT of intra-operative frozen section during radical prostatectomy in the world. It is properly powered to evaluate a difference in the recovery of EF for men undergoing RARP assessed by patient-reported outcome measures. It will provide evidence to guide the use of the NeuroSAFE technique around the world.

TRIAL REGISTRATION

NCT03317990 (23 October 2017). Regional Ethics Committee; reference 17/LO/1978.

Pathological processing of sentinel lymph nodes in endometrial carcinoma - routine aspects of grossing, ultra-staging, and surgico-pathological parameters in a series of 833 lymph nodes

Sentinel lymph nodes are widely accepted in the treatment of endometrial carcinoma. Whereas surgical aspects are well studied, the pathological work-up in terms of grossing, frozen section, and the so-called ultra-staging is still a matter of debate. This results in conflicting national or center-based recommendations. In a series of consecutive 833 sentinel lymph nodes from 206 patients in endometrial carcinomas, we compared three different grossing techniques and the use of frozen section in terms of anatomy, detection rates, and survival. In total, 42 macro-metastases, 6 micro-metastases, and 25 nodes with isolated tumor cells were found. Lymph nodes affected at least with micro-metastasis were about 0.5cm enlarged. Detection rates in lamellation technique increased with a step of 5.9% to 8.3% in comparison to bi-valved or complete embedding. The lamellation technique presented with a slight beneficial prognosis in pN0 subgroup (OS, p=0.05), which besides size effects might be attributed to trimming loss. In frozen section, this effect was less pronounced than expected (OS, p=0.56). Ultra-staging only revealed additional micro-metastases and isolated tumor cells. Exclusively, macro-metastases showed poor survival (p<0.001). In multivariate analysis, T-stage, subtype, and lympho-vascular invasion status outperformed this staging parameter significantly. Grossing of sentinel lymph nodes is the most essential step with evidence to prefer lamellation in 2 mm steps. Step sectioning should consider widely spaced protocols to exclude macro-metastases. Frozen sections might add value to the intra-operative assessment of endometrial carcinoma in selected cases. The excellent biological behavior of cases with isolated tumor cells might question the routine application of pan-cytokeratin as ultra-staging method.

Validation of whole slide imaging for frozen section diagnosis of lymph node metastasis: A retrospective study from a tertiary care hospital in Thailand

BACKGROUND

The use of whole slide imaging (WSI) for frozen section (FS) diagnosis is helpful, particularly in the context of pathologist shortages. However, there is minimal data on such usage in resource-limited settings. This study aims to validate the use of WSI for FS diagnosis of lymph node metastasis using a low-cost virtual microscope scanner with consumer-grade laptops at a tertiary care hospital in Thailand.

METHODS

FS slides were retrieved for which the clinical query was to evaluate lymph node metastasis. They were digitized by a virtual microscope scanner (MoticEasyScan, Hong Kong) using up to 40× optical magnification. Three observers with different pathology experience levels diagnosed each slide, reviewing glass slides (GS) followed by digital slides (DS) after two weeks of a wash out period. WSI and GS diagnoses were compared. The time used for scanning and diagnosis of each slide was recorded.

RESULTS

295 FS slides were retrieved and digitized. The first-time successful scanning rate was 93.6 %. The mean scanning time was 2 min per slide. Both intraobserver agreement and interobserver agreement of WSI and GS diagnoses were high (Cohen's K; kappa value >0.84). The time used for DS diagnosis decreased as the observer's experience with WSI increased.

CONCLUSIONS

Despite varying pathological experiences, observers using WSI provided accurate FS diagnoses of lymph node metastasis. The time required for DS diagnoses decreased with additional observer's experience with WSI. Therefore, a WSI system containing low-cost scanners and consumer-grade laptops could be used for FS services in hospital laboratories lacking pathologists.

Accuracy of definitive rapid onsite evaluation cytopathology diagnoses: Assessment of potentially critical diagnoses as a quality assurance measure

INTRODUCTION

Intraprocedural rapid onsite evaluation (ROSE) of cytology specimens enhances cytopathology practice. More recently, ROSE diagnoses, like frozen section (FS) diagnoses, have guided immediate clinical decisions. In this study, we evaluated the diagnostic accuracy of definitive ROSE diagnoses in our quality assurance system over a 52-month period.

MATERIALS AND METHODS

Cytopathology cases with ROSE from January 2017 to April 2021were retrieved from our laboratory information system. After excluding cases that were deferred or nondiagnostic/unsatisfactory, each definitive ROSE diagnosis (ie, negative for malignant cells or positive for malignant cells) was categorized as having agreement or disagreement with the final diagnosis. For comparison, concordance of FS diagnoses from the same time period were tabulated and compared to those of ROSE diagnoses by using χ² testing with P < 0.05 considered statistically significant.

RESULTS

Of the 1649 ROSE diagnoses, there were 15 disagreements (0.9%) with 1 final moderate interpretive disagreement (0.06%). By comparison, of the 17,469 FS diagnoses, there were 141 disagreements (0.8%) with 49 final moderate or major interpretive disagreements (0.3%). The remaining disagreements were minor. There were no statistically significant differences in the rates of final moderate and major interpretive disagreements.

CONCLUSIONS

The final interpretive disagreement rates for definitive ROSE and FS diagnoses were similar in this study. Given the expanding role of ROSE and its use for immediate clinical decisions in some cases, monitoring the accuracy of definitive diagnoses may serve as an initial quality assurance measure.

Hirschsprung disease managed with one-stage transanal endorectal pullthrough in a low-resource setting without frozen section

BACKGROUND

Over the past few decades, surgery for Hirschsprung's disease (HD) has evolved into a minimally invasive, single-stage procedure with excellent outcomes. Intraoperative frozen section biopsy is critical for this procedure to avoid the potential risk of leaving a retained aganglionic segment. However, this facility is not available in most low-income countries. Therefore, a two-stage procedure with an initial colostomy is still practiced in the developing world. We aimed to evaluate the outcome of single-stage transanal pullthrough performed in a facility without frozen section biopsy.

METHODS

A retrospective review of all patients who underwent transanal pullthrough in two teaching hospitals over a 6-year period (2015-2020).

RESULTS

Forty-seven children underwent transanal endorectal pullthrough (TERPT). Age at surgery ranged from 2 months to 6 years and mean weight was 8.7 kg. Barium enema did not show transition zone in 6 patients (12.8%) while others demonstrated short segment HD. Intraoperatively, the transition zone was visualized in 40 patients (85%). TERPT alone was performed in 35 (74.5%), TERPT with laparotomy to visualize transition zone in 9 (26.7%) and TERPT with transabdominal mobilization was required in 3 (6.4%). Definitive histopathologic examination revealed aganglionic segment pullthrough in 4 (8.5%) and transitional zone pullthrough in another 4 (8.5%). However, with long term follow up all eight children remained asymptomatic and no intervention was required.

CONCLUSIONS

Transanal pullthrough offers reduced number of surgeries and faster recovery. We have also observed a good functional outcome despite a discrepancy with pathology results. Overall, our data suggests it is a safe and viable option for the treatment of short segment HD in facilities where frozen section is not available.

Comparison of Frozen Section and Squash Cytology as Intra-Operative Diagnostic Tool in Pediatric CNS Tumors

BACKGROUND

Pediatric central nervous system (CNS) tumors have a different histological spectrum as compared to adults with the infantile group having even more varied and distinct histological profiles. Intra-operative diagnosis is especially important as it guides the neurosurgeon to tailor an approach which is best suited for a particular case. The aim of the study was to evaluate the diagnostic accuracy, sensitivity, specificity, positive predictive value, negative predictive value of frozen section (FS) and squash cytology and to find out the degree of correlation (kappa value) between the two procedures.

MATERIALS AND METHODS

A prospective study was conducted on 55 pediatric patients with clinicoradiologically diagnosed CNS lesions for a period of 2.5 years. Intra-operative squash smears and FS were made and stained with hematoxylin and eosin stain. Diagnosis made subsequently on paraffin embedded sections was taken as the gold standard.

RESULTS

Although the specificity (90%) and positive predictive value (96%) were comparable between the two procedures, sensitivity (91.4%) and negative predictive value (75%) of FS was more as compared to squash cytology. Both the diagnostic modalities showed substantial agreement (k = 0.728).

CONCLUSION

Even though the histological spectrum of pediatric CNS tumors is more varied than adults, FS gives a reasonable intra-operative diagnosis and better results when compared to squash alone.

Subareolar Tissue Biopsy Predicts Occult Nipple Involvement in Nipple-Sparing Mastectomies

OBJECTIVES

Subareolar tissue is examined during nipple-sparing mastectomy (NSM) to minimize the risk of occult malignancy within the preserved nipple. A positive subareolar tissue biopsy typically warrants subsequent nipple excision. We study the factors associated with a positive subareolar tissue biopsy, the rate of residual malignancy in subsequent nipple excisions, and the value of subareolar tissue biopsy intraoperative frozen section (IOF).

METHODS

We identified 1,026 consecutive NSMs with separately submitted subareolar tissue biopsies over a 5.5-year period. Clinicopathologic data were reviewed. We examined concordance rates between subareolar tissue biopsy and subsequent nipple excisions as well as IOF diagnosis and permanent control diagnosis.

RESULTS

Among cases of therapeutic NSM, the rate of a positive subareolar tissue biopsy was 7.2%. Multifocal/multicentric disease (P = .0005), presence of lymphovascular invasion (P = .033), and nodal involvement (P = .006) were significantly associated with a positive subareolar tissue biopsy. Thirty-nine of 41 cases with positive subareolar biopsies underwent subsequent nipple excision, with 20 (51%) showing residual carcinoma. Among all IOF samples, 9 (3.3%) showed a discrepancy between the IOF and permanent diagnoses, mostly because of false-negatives.

CONCLUSIONS

A positive subareolar tissue biopsy predicts residual carcinoma in the excised nipples in 51% of cases. IOF is accurate and reliable.

Splenogonadal fusion: aiding detection and avoiding radical orchidectomy

Splenogonadal fusion is a rare benign congenital anomaly in which there is an abnormal connection between the gonad and the spleen. It was first described over 100 years ago with limited reports in the literature since then. Its similarity in presentation to testicular neoplasia poses a significant challenge in diagnosis and management, often resulting in radical orchidectomy. We present the case of a 31-year-old man who presented with a rapidly growing left-sided testicular mass and suspicious ultrasound findings; histology from the subsequent radical inguinal orchidectomy showed findings consistent with splenogonadal fusion. We describe points for consideration in the clinical history, examination and imaging that could suggest splenogonadal fusion, including preoperative technetium-99m-sulfur colloid imaging and intraoperative frozen section evaluation, which may confirm the diagnosis and prevent unnecessary orchidectomy.

Validity of surgical decision based on intraoperative frozen section diagnosis for unconfirmed pulmonary nodules with previous malignancy

OBJECTIVES

The lung is a major target organ of metastasis in several cancers. To distinguish primary lung cancer from pulmonary metastases is a clinical challenge. Small pulmonary nodules (PNs) are frequently diagnosed by frozen section diagnosis (FSD) intraoperatively after resection. Intraoperative FSD is very important to determine the extent of subsequent surgical procedures. This study aimed to know the validity of surgical decision based on FSD for preoperatively unconfirmed PN with previous malignancy.

METHODS

We retrospectively evaluated 96 patients with suspected malignant PN who underwent intraoperative FSD between 2018 and 2020. Intraoperative FSD, final diagnosis, and surgical procedure data were examined.

RESULTS

Surgical procedure adequacy, based on FSD for preoperatively unconfirmed PN with previous malignancy, was 91% (88/96). The overall diagnostic accuracy of FSD was 83.3% (80/96). Discrepancy was noted in two cases (2.1%), and conclusive diagnosis could not be reached intraoperatively in 14 cases (14.6%). A second surgery was required in three patients and no additional excision for primary lung cancer was performed in three patients. Conversely, there were three cases of over-surgery, namely, lobectomy for pulmonary metastasis.

CONCLUSIONS

Surgical decision-making based on FSD for preoperatively unconfirmed PN in patients with previous malignancy was generally adequate. However, there were inadequate or excessive surgical procedures due to limitations in the accuracy of intraoperative FSD. Improving the accuracy of intraoperative FSD is a necessary step for obtaining adequate surgical decision-making and precision medicine.

Frozen Section or Intraoperative Cytology: Are We Ready for a Paradigm Shift in Thoracic Surgery?

Intraoperative frozen sections of specimens taken during thoracic surgery are widely seen as the gold standard. However, the accuracy of intraoperative cytology remains contentious. The study aims to estimate the value of intraoperative cytology by analyzing feasibility, accuracy, time requirements, and possible limitations when compared to standard frozen sections. To this end, we examined a total of 532 intraoperatively harvested specimens out of the 518 resected thoracic tumors from 360 patients between August 2016 and August 2017. The specimens were subject to intraoperative rapid cytology that was later counter compared to the final histology results. The mean time between the intraoperative harvesting and arrival at the laboratory was 2.23 min, and it took a further 3.5 min until the results were communicated to the surgeon. Cytologically, 218 cases (41%) were classified as malignant, 291 (55%) as benign, and 23 (4%) remained unclear. In 55 malignant cases, we observed additional benign formations. The final histological examination performed later yielded 267 malignant and 265 benign cases. Therefore, the sensitivity and specificity of rapid intraoperative cytology were 82% and 99%, respectively, with a negative/positive predictive value of 86%/99%. We conclude that the intraoperative rapid cytology is a fast, accurate, sensitive, and specific procedure for intraoperative decision making and is a distinctly helpful alternative or adjunct for the thoracic surgeon, providing that one is aware of the plausible limitations of this technique.

Identification of three novel B cell epitopes in ORF2 protein of the emerging goose astrovirus and their application

The outbreak of goose gout disease caused by novel goose astrovirus type 1 (GAstV-1) has resulted in huge economic losses to the goose industry in China since 2017. However, little is known about the B cell epitopes in major antigen of GAstV-1 and the serological approach for detection of GAstV-1 is not available. In this study, three novel monoclonal antibodies (mAbs) against the ORF2 protein were first generated and designated as 3G6, 5H7, and 6C6, respectively. Epitope mapping revealed that mAb 3G6, 5H7, and 6C6 recognized ₆₉₅AVRFEKGGHE₇₀₄, ₆₈₅EKALSAPQAG₆₉₄, and ₆₃₅DDDPLSDVTS₆₄₄ in ORF2, respectively. Sequence alignments found that the three epitopes were highly conserved in GAstV-1 but not in other AAstV members. Moreover, a mAb-based sandwich ELISA for the detection of GAstV-1 was first developed using mAb 6C6. The sandwich ELISA only reacted with GAstV-1 but not with GAstV-2 and the other goose-associated viruses tested. The limit of the detection of the sandwich ELISA reaches 1.58 × 10³ TCID₅₀/mL of GAstV-1. Notably, mAb 6C6 could also efficiently react with the GAstV-1 in tissue frozen sections of the clinical infected goose through IFA. The mAbs generated in this study pave the way for further studying on the role of ORF2 in the infection and pathogenesis of GAstV, and the sandwich ELISA and the tissue frozen section-IFA approaches established here provide efficient and rapid serological diagnostic tools for detection of GAstV-1. KEY POINTS: • Three novel B cell epitopes were identified in ORF2 of GAstV-1. • mAb-based ELISA and IFA for detection of GAstV-1 were developed.

Limited utility of intraoperative frozen sections in primary malignant tumours involving long bones - A multicenter analysis of 475 cases

Background

In the surgical removal of primary malignant tumours involving long bones, intraoperative frozen sections are used to ascertain the adequacy of tumour clearance. However, with the improved imaging modalities that provide better foreknowledge of the tumour extent, it is possible that the arduous task of performing frozen sections can be safely avoided. This would not only save procedural time but also reduce hospital costs. Presently, there are no clear guidelines regarding the modality required intraoperatively to assess tumour margins in these cases. Hence, in our retrospective multicentre analysis, we aimed at determining the usefulness of frozen sections in these cases.

Materials and methods

Our study is a 3-centre retrospective analysis of 475 cases (513 tumour margins) involving the surgical removal of primary malignancies of long bones. The preoperative Magnetic Resonance Imaging (MRI) and intraoperative assessment of the split specimen of the tumours were used to determine marginal clearance in all the cases in addition to frozen sections in 410 of the margins.

Results

Of the 410 frozen sections (centres 1 and 2), only one margin was reported positive and another reported indeterminate. All other margins were reported negative. In the first case, a 2 cm additional bone-cut was done whereas in the second, the procedure was proceeded based on the intraoperative agreement without re-cutting the margin. All these margins were negative in the final histopathology. In addition, in Centre 3, where frozen sections were not available, all the 103 cases had negative margins in the final histopathology.

Conclusion

In primary malignancies involving long bones, intraoperative decision making with the aid of MRI has been sufficiently accurate in identifying the required tumour margin without frozen sections. Hence, the added time and cost incurred by doing an additional procedure can be avoided in these cases.

•

Currently, there are no guidelines on the optimal marginal thickness required for tumour clearance in long bone tumours.

•

Our frozen section study analysed the correlation between frozen sections and final histopathology results.

•

Only 1 positive frozen smear was seen which was negative in the histopathology showing limited utility of frozen sections.

Can addition of frozen section analysis to preoperative endometrial biopsy and MRI improve identification of high-risk endometrial cancer patients?

Background

Surgeons sometimes have difficulty determining which result to favor when preoperative results (MRI + preoperative endometrial biopsy [pre-op EB]) differ from intraoperative frozen section histology (FS) results. Investigation of how FS can complement ordinary preoperative examinations like MRI and pre-op EB in identification of patients at high risk of lymph node metastasis (high-risk patients) could provide clarity on this issue. Therefore, the aim of this study is to assess the utility of pre-op EB, MRI and FS results and determine how to combine these results in identification of high-risk patients.

Methods

The subjects were 172 patients with endometrial cancer. Patients with a histological high-grade tumor (HGT), namely, grade 3 endometrioid cancer, clear cell carcinoma or serous cell carcinoma, or with any type of cancer invading at least half of the uterine myometrium were considered high-risk. Tumors invading at least half of the uterine myometrium were classified as high-stage tumors (HST). We compared (a) detection of HGT using pre-op EB versus FS, (b) detection of HST using MRI versus FS, and (c) identification of high-risk patients using MRI + pre-op EB versus FS. Lastly, we determined to what degree addition of FS results improves identification of high-risk patients by routine MRI + pre-op EB.

Results

(a) Sensitivity, specificity, and accuracy for detecting HGT were 59.6, 98.4 and 87.8% for pre-op EB versus 55.3, 99.2 and 87.2% for FS (P = 0.44). (b) These figures for detecting HST were 74.4, 83.0 and 80.8% for MRI versus 46.5, 99.2 and 86.0% for FS (P < 0.001). (c) These figures for identifying high-risk patients were 78.3, 85.4 and 82.6% for MRI + pre-op EB versus 55.1, 99.0 and 81.2% for FS (P < 0.001). The high specificity of FS improved the sensitivity of MRI + pre-op EB from 78.3 to 81.2%, but this difference was not statistically significant (P < 0.16).

Conclusion

Frozen section enables identification of high-risk patients with nearly 100% specificity. This advantage can be used to improve sensitivity for identification of high-risk patients by routine MRI + pre-op EB, although this improvement is not statistically significant.

The Role of Frozen Section Examination During Inguinal Exploration in Men with Inconclusive Testicular Tumors: A Systematic Review and Meta-analysis

For inconclusive testicular tumors with negative tumor markers, frozen section examination (FSE) during inguinal exploration is recommended. However, FSE is time-consuming and therefore often not requested. Furthermore, the exact diagnostic benefit remains poorly defined. We performed a systematic review and meta-analysis summarizing 12 published studies and our own series of FSE in patients with inconclusive testicular tumors, resulting in a cohort of 1052 FSEs. FSE showed sensitivity of 99% and specificity of 96% with a positive predictive value of 98% and a negative predictive value of 97%. Most importantly, one-third of all testicular tumors investigated were correctly identified as being suitable for testis-sparing surgery and orchiectomy could be avoided. For patients with inconclusive testicular tumors, FSE is useful for deciding whether testis-sparing surgery is an option or whether radical orchiectomy should be performed. Thus, these patients should be optimally treated in institutions where FSE is available. PATIENT SUMMARY: We found that intraoperative examination of a frozen section is useful in deciding on whether the entire or only parts of the testicle can be removed. We conclude that frozen section examination should be offered to men with small testicular lesions and negative tumor markers.

Neurovascular structure-adjacent frozen-section examination robotic-assisted radical prostatectomy: outcomes from 500 consecutive cases in the UK

The purpose is to report the United Kingdom's largest single-centre experience of robotically assisted laparoscopic radical prostatectomies (RALP), using the neurovascular structure-adjacent frozen-section (NeuroSAFE) technique. We describe the utilisation and outcomes of this technique. This is a retrospective study from 2012 to 2019 on 520 patients undergoing NeuroSAFE RALP at our Institution. Our Institution's database was analysed for false-positive frozen-section (FS) margins as confirmed on paraffin histopathological analysis: functional outcomes of potency, continence, and biochemical recurrence (BCR). The median (range) of console time was 145 (90-300) min. In our cohort, positive FS was seen in 30.7% (160/520) of patients, with a confirmatory paraffin analysis in 91.8% of our patients' cohort (147/160). The neurovascular bundles (NVBs) that underwent secondary resection contained tumour in 26.8% (43/160) of the cases. Biochemical recurrence (BCR) was 6.7% (35/520), of which FS was positive in 40% (14/35) of those cases. There were insufficient evidence of a statistical association of urinary incontinence and positive surgical margin rates according to NS or NVB resection. NeuroSAFE enables intraoperative confirmation of the oncologic safety of a NS procedure. Patients with a positive FS on NeuroSAFE can be converted to a negative surgical margin (NSM) by ipsilateral wide resection. This spared 1 in 4 men from positive margins posterolaterally in our series. Limitations are the absence of a matched contemporary cohort of NS RALP without NeuroSAFE in our centre.

Borderline ovarian tumor frozen section diagnoses with features suspicious of invasive cancer: a retrospective study

Background

A frozen section diagnosis of a borderline ovarian tumor with suspicious features of invasive carcinoma (“at least borderline” or synonymous descriptions) presents us with the dilemma of whether or not to perform a full ovarian cancer staging procedure. Quantification of this dilemma may help us with the issue of this clinical decision. The present study assessed and compared both the prevalence of straightforward borderline and “at least borderline” frozen section diagnoses and the proportion of these women with a final histopathological diagnosis of invasive carcinoma, with a special interest in histologic subtypes.

Methods

A retrospective cohort study was performed in three hospitals in The Netherlands. All women that underwent ovarian surgery with perioperative frozen section evaluation in one of these hospitals between January 2007 and July 2018 were identified and included in case of a borderline or “at least borderline” frozen section diagnosis and a borderline ovarian tumor or invasive carcinoma as a final diagnosis.

Results

A total of 223 women were included, of which 41 women (18.4%) were diagnosed with “at least borderline” at frozen section. Thirteen of forty-one women (31.7%) following “at least borderline” frozen section diagnosis and 14 of 182 women (7.7%) following a straightforward borderline frozen section diagnosis were diagnosed with invasive carcinoma at paraffin section evaluation (p < 0.001). When compared to straightforward borderline frozen section diagnoses, the proportion of women diagnosed with invasive carcinoma increased from 3.1 to 35.7% for serous tumors (p = 0.001), 10.0 to 21.7% for mucinous tumors (p = 0.129) and 50.0 to 75.0% (p = 0.452) in case of other histologic subtypes following an “at least borderline” frozen section diagnosis.

Conclusions

Overall, when compared to women with a decisive borderline frozen section diagnosis, women diagnosed with “at least borderline” frozen section diagnoses were found to have a higher chance of carcinoma upon final diagnosis (7.7% vs 31.7%). Especially in the serous subtype, full staging during initial surgery might be considered after preoperative consent to prevent a second surgical procedure or chemotherapy in unstaged women. Further studies are needed to evaluate whether additional sampling in case of an “at least borderline” diagnosis may decrease the risk of surgical over-treatment.

Frozen-Permanent Section Discrepancy Rate in Oral Cavity and Oropharyngeal Squamous Cell Carcinoma

Frozen section evaluation of head and neck squamous cell carcinoma (SCC) is critical for margin status and subsequent patient therapy. In this study, we retrospectively reviewed the rate of frozen-permanent section discrepancies in blocks with two frozen section levels compared to ≥ three levels in oral cavity and oropharyngeal SCCs. A search of the cases with both intraoperative frozen sections and corresponding permanent sections for SCCs in the oral cavity and oropharynx was performed. Frozen sections and permanent slides were compared. The nature of discrepancies was assigned to one of the following: change in diagnosis, margin status, or distance of the tumor from the margin. The cause of the discrepancy was designated as one of the following: block sampling, gross sampling, interpretation, or technical error. The pathologist experience, frozen section technical experience, and intraoperative impact of each discrepancy were also evaluated. A total of 654 frozen and corresponding permanent blocks were assessed. For 532 of the frozen section blocks, two levels were cut, while 122 frozen section blocks had ≥ three levels. Thirty-five frozen-permanent section discrepancies were observed (5.4% of all blocks). Among these, 2.5% had a possible or definitive intraoperative impact. The percentage of discrepancies in the ≥ three levels group (5.7%) was slightly higher than the two-level group (5.3%), and this difference was not statistically significant. For the two-level group, the overall block sampling error rate was 4.5%. This was not significantly different from the 4.1% block sampling error rate seen in the ≥ three levels group. The rate of block sampling discrepancy did not show significant differences based on attending or frozen section technical experience. A change in margin distance (closer margin detected on permanent) occurred in 4% of the blocks and involved 16% of the patients. This review of oral cavity and oropharynx SCCs frozen/permanent section discrepancies shows that the error rate is not significantly different depending on the number of levels cut. The results suggest that always performing more than two frozen section levels may not yield a decreased discrepancy rate. A change in margin distance occurred quite frequently, but only in rare cases it had a definitive impact on the intraoperative management. Given the importance of correct intraoperative diagnosis in patient management, additional levels may be warranted depending on the clinical scenario.

Is intraoperative margin sampling necessary in inverted papilloma resection?

PURPOSE

To explore the association between intraoperative surgical margin sampling by the frozen sections and recurrence in inverted papilloma surgery.

METHODS

A multicenter, retrospective study of patients who underwent attachment-oriented IP resection in four tertiary care medical centers with a minimal follow-up of 36 months.

RESULTS

The study included 220 surgeries with a mean follow-up period of 49 months (range 36-204). The endoscopic approach was used in all but 4 cases; 73% of procedures were primary. Overall recurrence was 10.45% (n = 23). Squamous cell carcinoma was found in 5 cases (2.2%). Intraoperative margin sampling was obtained in 145 cases. There was no difference in the recurrence rate between frozen section and no-frozen section groups (p = 0.44). Furthermore, margin sampling in various sites of tumor origin, in cases with concomitant nasal polyps (p = 0.53) and in revision cases (p = 0.08) showed no correlation with recurrence. In 26 cases when the surgery was extended following a positive frozen section, there was a significantly higher recurrence rate (OR = 6.94).

CONCLUSIONS

According to our results, intraoperative margin sampling did not affect the recurrence rate of IP, and therefore, its routine use should be questioned.

Unplanned excision of soft tissue sarcoma: does it impact the accuracy of intra-operative pathologic assessment at time of re-excision?

PURPOSE

An "unplanned excision" refers to soft tissue sarcomas excised without planning imaging studies and a diagnostic biopsy, resulting in the presence of residual disease and usually necessitating a re-excision procedure. We aimed to assess the impact of previous unplanned excisions on the intra-operative pathologic assessment at the time of re-excision, in terms of need to perform repeat assessments and the accuracy to predict margin status of the final pathologic specimen.

METHODS

Data was collected for all patients with extremity soft tissue sarcoma who had undergone wide local excision limb salvage surgery or amputation between 2012 and 2017. Intra-operative pathologic assessment with frozen sections was performed in all cases and was classified as negative, negative but close (< 1 mm), and positive.

RESULTS

A total of 173 patients with extremity soft tissue sarcoma were included, 54 in the unplanned excision group and 119 in the planned excision group. The accuracy of intra-operative pathologic assessment to predict the margin status on final pathology was similar between groups (87% unplanned vs. 90.7% planned excisions). However, the need for repeat intra-operative pathologic assessment and subsequent resection due to microscopically positive margins was found to be higher within the unplanned excision group ((p = 0.04), OR = 3.2 (95% CI: 1.1-9.1, p = 0.048)).

CONCLUSIONS

Intra-operative pathologic assessment of resection margins had a similar accuracy in planned and unplanned excisions; however, unplanned excisions showed a higher risk of re-resection during the same surgical setting.

Frozen Section Quality Assurance

OBJECTIVES

Composite frozen section turnaround time has limited value, precluding assessment of certain processes: slide preparation (technical) and diagnosis (interpretation). We examined whether measuring these elements could identify delays, hypothesizing that longer times were related to (1) inefficient technical processes and (2) case-specific diagnostic challenges.

METHODS

Technical and interpretive times were determined for 1,992 specimens submitted for frozen section in 2017; the data were sorted by surgical specialty. Mean and quartile times were determined for each category with all specimens assessed equally, including those with multiple frozen section blocks.

RESULTS

Technical times were significantly longer than interpretive times. Specialty grouping facilitated trend identification and enabled assessment of technical and interpretation challenges. We identified technical issues with certain gross specimens involving overdissection and interpretation delays for specific neoplasms and margins.

CONCLUSIONS

Measuring technical and interpretative times and subcategorizing by specialty has aided the assessment of frozen section processing in our laboratory, enabling case isolation for process improvement.

Risk stratification of parotid neoplasms based on intraoperative frozen section and preoperative fine needle aspiration cytology

PURPOSE

This study aims to determine the relationship of frozen section (FS) to final histology and determine how incorporating FS may change preoperative malignancy risk estimates based on preoperative fine needle aspiration cytology (FNAC). The secondary aim is to determine if FS is useful in influencing intraoperative decision-making.

METHODS

Retrospective review of 426 intraoperative FS for parotidectomies performed for primary parotid lesions.

RESULTS

Risk of malignancy with a benign FS was 2.5%, with indeterminate 36.1%, and with malignant 100%. Incorporating FS to fine needle aspiration for cytology helped to stratify malignancy risk especially in the Milan categories of atypia of undetermined significance, neoplasm of uncertain malignant potential and non-diagnostic categories, where a malignant FS increased malignancy risk significantly. FS was only able to identify 11% of high-risk histological subtypes for which a neck dissection would be recommended.

CONCLUSIONS

FS may be used to stratify malignancy risk intraoperatively but has limited utility in clinical decision-making to perform a neck dissection and more extensive parotid resection in high-risk histological subtypes.

Evaluation of frozen section biopsy for fast track diagnosis of endometrial pathology in high-risk women with abnormal uterine bleeding

OBJECTIVE

To study the accuracy of frozen section biopsy for endometrial pathology in high-risk women with abnormal uterine bleeding (AUB).

STUDY DESIGN

A case-control study was conducted between November 2017 to April 2019, a total of 150 women with postmenopausal bleeding, perimenopausal AUB, and high-risk women of age < 40 years with AUB were recruited. All women underwent transvaginal sonography and Doppler, based on age-appropriate endometrial thickness cut-offs 80 women then underwent hysteroscopy. Based on hysteroscopy, women suspicious of malignancy were taken as cases (n = 40) and those with benign findings as controls (n = 40). All cases and controls underwent dilatation and curettage (D & C) with frozen section (FS) and routine histopathology.

RESULTS

The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), positive likelihood ratio (LR), negative LR, and overall test accuracy of FS were 90.9%, 93.19%, 83.33%, 96.19%, 13.8, 0.1 and 86.25% respectively for diagnosing endometrial hyperplasia and cancer taking histopathology as the gold standard. Correlation between frozen section biopsy and histopathology was highly significant (p < 0.001) on D & C specimens and the level of agreement was good (K = 0.778).

CONCLUSION

In women suspicious of malignancy on hysteroscopy, frozen section has high accuracy on D&C specimen and can be used to diagnose endometrial hyperplasia and cancer in an effort to fast-track investigations and work-up for definitive treatment while awaiting final histopathology.