Prognostic value of frozen section in t1, t2 carcinoma of oral cavity

Margins in Stage I and II Oral Cavity Squamous Cell Carcinoma: A Review From the American Head and Neck Society

Importance

The assessment and management of surgical margins in stage I and II oral cavity squamous cell carcinoma is one of the most important perioperative aspects of oncologic care, with profound implications for patient outcomes and adjuvant therapy. Understanding and critically reviewing the existing data surrounding margins in this context is necessary to rigorously care for this challenging group of patients and minimize patient morbidity and mortality.

Observations

This review discusses the data related to the definitions related to surgical margins, methods for assessment, specimen vs tumor bed margin evaluation, and re-resection of positive margins. The observations presented emphasize notable controversy within the field about margin assessment, with early data coalescing around several key aspects of management, although studies are limited by their design.

Conclusions and Relevance

Stage I and II oral cavity cancer requires surgical resection with negative margins to obtain optimal oncologic outcomes, but controversy persists over margin assessment. Future studies with improved, well-controlled study designs are required to more definitively guide margin assessment and management.

Frozen Section Analysis and Real-Time Magnetic Resonance Imaging of Surgical Specimen Oriented on 3D Printed Tongue Model to Assess Surgical Margins in Oral Tongue Carcinoma: Preliminary Results

Background

A surgical margin is the apparently healthy tissue around a tumor which has been removed. In oral cavity carcinoma, a negative margin is considered ≥ 5 mm, a close margin between 1 and 5 mm, and a positive margin ≤ 1 mm. Currently, the intraoperative surgical margin status is based on the visual inspection and tissue palpation by the surgeon and intraoperative histopathological assessment of the resection margins by frozen section analysis (FSA). FSA technique is limited and susceptible to sampling errors. Definitive information on the deep resection margins requires postoperative histopathological analysis.

Methods

We described a novel approach for the assessment of intraoperative surgical margins by examining a surgical specimen oriented through a 3D-printed specific patient tongue with real-time Magnetic Resonance Imaging (MRI). We reported the preliminary results of a case series of 10 patients, prospectively enrolled, with oral tongue carcinoma who underwent surgery between February 2020 and April 2021. Two radiologists with 5 and 10 years of experience, respectively, in Head and Neck radiology in consensus evaluated specimen MRI and measured the distance between the tumor and the specimen surface. We performed intraoperative bedside FSA. To compare the performance of bedside FSA and MRI in predicting definitive margin status we computed the weighted sensitivity (SE), specificity (SP), accuracy (ACC), area under the ROC curve (AUC), F1-score, Positive Predictive Value (PPV), and Negative Predictive Value (NPV). To express the concordance between FSA and ex-vivo MRI we reported the jaccard index.

Results

Intraoperative bedside FSA showed SE of 90%, SP of 100%, F1 of 95%, ACC of 0.9%, PPV of 100%, NPV (not a number), and jaccard of 90%, and ex-vivo MRI showed SE of 100%, SP of 100%, F1 of 100%, ACC of 100%, PPV of 100%, NPV of 100%, and jaccard of 100%. These results needed to be validated in a larger sample size of 21- 44 patients.

Conclusion

The presented method allows a more accurate evaluation of surgical margin status, and the first clinical experiences underline the high potential of integrating FSA with ex-vivo MRI of the fresh surgical specimen.

Accuracy of Frozen Section Examination in Oral Cavity Cancers

PURPOSE

This study aimed to compare the intraoperative frozen section with the surgical margin in the postoperative surgical margins of the postoperative pathology of oral squamous cell carcinomas in order to examine the reliability of the frozen section.

METHODS

A retrospective analysis was conducted for patients who underwent surgery for oral squamous cell carcinoma in a tertiary hospital between January 2018 and 2019. The intraoperative frozen section examinations, grade of the tumor, number of lymph nodes, number of affected lymph nodes, depth of invasion, perineural invasion, lymphovascular invasion, and extranodal extension were recorded from the pathological records. The concordance between the frozen section examination and postoperative pathology 2 methods was examined using the Cronbach α coefficient. Sensitivity, specificity, positive predictive value, negative predictive value regarding surgical margins, and accuracy were calculated and reported.

RESULTS

Overall, 181patients who underwent surgery for oral cavity cancers were included; 118 (65.2%) were males. The mean (± standard deviation) age of the included participants was 57.4 ± 16.1 years. The most common tumour subsite was the tongue (n = 71, 39.2%). There was concordancy between the frozen, positive intraoperative malignancy and the postoperative pathology malignancy. The frozen, negative intraoperative malignancy and postoperative safe surgical margin did not significantly differ.

CONCLUSION

As a result of intraoperative frozen examination, we found conformity between the postoperative pathology results of patients with positive and negative surgical margins. Frozen section examination could be used safely to examine intraoperative surgical margins of oral squamous cell carcinoma.

Intraoperative Margin Assessment in Head and Neck Cancer: A Case of Misuse and Abuse?

Surgical removal with negative margins is the preferred management of oral squamous cell carcinomas. This review summarizes statements by professional organizations and data supporting the specimen-driven approach to margin assessment. Practical aspects of the intraoperative margin assessment, as guided by gross examination, are presented. The most cost- and time-efficient method of intraoperative margin assessment depends on desired margin clearance and likelihood of other adverse histologic factors, such as extranodal extension, perineural invasion, which are likelier in advanced carcinomas. Intraoperative surgeon-pathologist communication can be improved by reporting to surgical team gross distances to all or selected closest margins, before choosing margins for microscopic frozen examination. Case specific mitigation strategies to minimize the negative impact of tumor-bed driven margin assessment or of suboptimal margin revision are proposed. Based on size, shape, histology, size of carcinoma at the margin, and orientation of the additional tissue, margin revision may be judged as adequate (conversion of a positive margin into a negative one), inadequate (positive margin remains positive), or indeterminate. The significance of anatomic subsite based labeling, radial margin sampling from the main resection specimen, and the relationship between the distance to closest margin and local control are highlighted. The modern definition of safe margin would account for other parameters, such as perineural invasion. An updated approach to resolution of frozen versus permanent sampling issues is outlined. Future studies are needed to design and validate risk models that would help to determine for individual patient what represents a safe margin and how to judge the quality of margin revision.

Does Clearance of Positive Margins Improve Local Control in Oral Cavity Cancer? A Meta-analysis

OBJECTIVES

To compare local recurrence-free survival (LRFS) in early oral cavity cancer (OCC) patients with positive/close frozen section (FS) cleared with further resection (R1 to R0) or positive FS not cleared (R1) to those with negative margins on initial FS analysis (R0).

DATA SOURCES

PubMed, EMBASE, and Cochrane.

REVIEW METHODS

We followed the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) for reporting in our study. Only English-language articles that included patients with OCC and local recurrence (LR) comparisons between R0 and initially R1 to final R0 or final R1 groups were included. We requested the raw data from the corresponding authors of eligible studies and performed an individual participant data (IPD) meta-analysis of LRFS outcomes across groups.

RESULTS

Pooled LRFS data from 8 studies showed that patients in the R1 to R0 group had worse LRFS compared to the R0 group (hazard ratio [HR] = 2.897, P < .001). Patients in the R1 group were also found to have worse LRFS compared to the R0 group (HR = 3.795, P < .001). When compared to final R1 group, the initially R1 to final R0 only showed a trend toward better LRFS.

CONCLUSION

Margin revision of initially positive margins to "clear" based on FS guidance does not equate to an initially negative margin and does not significantly improve local control. These findings call into question the effectiveness of the current methodology of intraoperative FS in OCC resections and call for a prospective study to determine what system of resected specimen analysis best predicts completeness of resection.

Intraoperative Margin Assessment in Early Oral Squamous Cell Carcinoma

The surgical method of margin sampling affects local control, pathologists' approach to margin sampling, and clarity of pathology reports. Studies have shown that exclusive reliance on tumor bed margins is associated with worse local control and should be avoided. En bloc resections and margins obtained from the resection specimen remain the "gold standard." Successful surgical treatment of early carcinomas of the oral cavity relies on close cooperation between surgeons and pathologists on issues of specimen orientation and margin sampling.