Specimen oriented intraoperative margin assessment in oral cavity and oropharyngeal squamous cell carcinoma

OBJECTIVE

Evaluate the oncologic outcomes and cost analysis of transitioning to a specimen oriented intraoperative margin assessment protocol from a tumour bed sampling protocol in oral cavity (OCSCC) and oropharyngeal squamous cell carcinoma (OPSCC).

STUDY DESIGN

Retrospective case series and subsequent prospective cohort study SETTING: Tertiary care academic teaching hospital SUBJECTS AND METHODS: Retrospective case series of all institutional T1-T2 OCSCC or OPSCC treated with primary surgery between January 1st 2009 - December 31st 2014. Kaplan-Meier survival estimates with log rank tests were used to compare patients based on final margin status. Cost analysis was performed for escalation of therapy due to positive final margins. Following introduction of a specimen derived margin protocol, successive prospective cohort study of T1-T4 OCSCC or OPSCC treated with primary surgery from January 1st 2017 - December 31st 2018. Analysis and comparison of both protocols included review of intraoperative margins, final pathology and treatment cost.

RESULTS

Analysis of our intra-operative tumour bed frozen section protocol revealed 15 of 116 (12.9%) patients had positive final pathology margins, resulting in post-operative escalation of therapy for 14/15 patients in the form of re-resection (7/14), radiation therapy (6/14) and chemoradiotherapy (1/14). One other patient with positive final margins received escalated therapy for additional negative prognostic factors. Recurrence free survival at 3 years was 88.4 and 50.7% for negative and positive final margins respectively (p = 0.048). Implementation of a specimen oriented frozen section protocol resulted in 1 of 111 patients (0.9%) having positive final pathology margins, a statistically significant decrease (p < 0.001). Utilizing our specimen oriented protocol, there was an absolute risk reduction for having a final positive margin of 12.0% and relative risk reduction of 93.0%. Estimated cost avoidance applying the specimen oriented protocol to our previous cohort was $412,052.812017 CAD.

CONCLUSION

Implementation of a specimen oriented intraoperative margin protocol provides a statistically significant decrease in final positive margins. This change in protocol leads to decreased patient morbidity by avoiding therapy escalation attributable only to positive margins, and avoids the economic costs of these treatments.

Accuracy of Frozen Section Analysis of Urethral and Ureteral Margins During Radical Cystectomy for Bladder Cancer: A Systematic Review and Diagnostic Meta-Analysis

CONTEXT

The question of the ability of frozen section analysis (FSA) to accurately detect malignant pathology intraoperatively has been discussed for many decades.

OBJECTIVE

We aimed to conduct a systematic review and meta-analysis assessing the diagnostic estimates of FSA of the urethral and ureteral margins in patients treated with radical cystectomy (RC) for bladder cancer (BCa).

EVIDENCE ACQUISITION

The MEDLINE and EMBASE databases were searched in February 2021 for studies analyzing the association between FSA and the final urethral and ureteral margin status in patients treated with RC for BCa. The primary endpoint was the value of pathologic detection of urethral and ureteral malignant involvement with FSA during RC compared with the final margin status. We included studies that provided true positive, true negative, false positive, and false negative values for FSA, which allowed us to calculate the diagnostic estimates.

EVIDENCE SYNTHESIS

Fourteen studies, comprising 8208 patients, were included in the quantitative synthesis. Forest plots revealed that the pooled sensitivity and specificity for FSA of urethral margins during RC were 0.83 (95% confidence interval [CI] 0.38-0.97) and 0.95 (95% CI 0.91-0.97), respectively. While for the FSA of ureteral margins, the pooled sensitivity and specificity were 0.77 (95% CI 0.67-0.84) and 0.97 (95% CI 0.95-0.98), respectively. Calculated diagnostic odds ratios indicated high FSA effectiveness, and patients with a positive urethral or ureteral margin at final pathology are over 100 times more likely to have positive FSA than patients without margin involvement at final pathology. Area under the curves of 96.6% and 96.7% were reached for FSA detection of urethral and ureteral tumor involvement, respectively.

CONCLUSIONS

Intraoperative FSA demonstrated high diagnostic performance in detecting both urethral and ureteral malignant involvement at the time of RC for BCa. FSA of both urethral and ureteral margins during RC is accurate enough to be of great value in the routine management of BCa patients treated with RC. While its specificity was great to guide intraoperative decision-making, its sensitivity remains suboptimal yet.

PATIENT SUMMARY

We believe that the frozen section analysis of both urethral and ureteral margins during radical cystectomy should be considered more often in urologic practice, until quality of life-based cost-effectiveness studies can identify patients within each institution who are unlikely to benefit from it.

Positive frozen section during reimplantation increases the risk of treatment failure in two-stage exchange arthroplasty even in patients with normal ESR and CRP

AIMS

It can be extremely challenging to determine whether to perform reimplantation in patients who have contradictory serum inflammatory markers and frozen section results. We investigated whether patients with a positive frozen section at reimplantation were at a higher risk of reinfection despite normal ESR and CRP.

METHODS

We retrospectively reviewed 163 consecutive patients with periprosthetic joint infections (PJIs) who had normal ESR and CRP results pre-reimplantation in our hospital from 2014 to 2018. Of these patients, 26 had positive frozen sections at reimplantation. The minimum follow-up time was two years unless reinfection occurred within this period. Univariable and multivariable logistic regression analyses were performed to identify the association between positive frozen sections and treatment failure.

RESULTS

Treatment failure occurred in eight (30.77%) of the 26 PJI patients with positive frozen sections at reimplantation, compared with 13 (9.49%) of 137 patients with negative results. In the multivariate analysis, positive frozen section increased the risk of failure (odds ratio 4.70; 95% confidence interval (CI) 1.64 to 13.45). The mean number of months to reinfection was lower in the positive frozen section group than in the control group (p = 0.041). While there were nine (34.62%) patients with positive frozen section and 25 (18.25%) patients with negative frozen section who had prolonged antibiotic use (p = 0.042), the mean duration of antibiotic use was comparable in two groups. Synovial white blood cell count (p = 0.137) and polymorphonuclear leucocyte percentage (p = 0.454) were not associated with treatment failure in logistic regression model.

CONCLUSION

Positive frozen section at reimplantation was independently associated with subsequent failure and earlier reinfection, despite normal ESR and CRP levels pre-reimplantation. Surgeons should be aware of the risk of treatment failure in patients with positive frozen sections and carefully consider benefits of reimplantation. Cite this article: Bone Joint J 2021;103-B(5):916-922.

Digital Frozen Sections with Fluorescence Confocal Microscopy During Robot-assisted Radical Prostatectomy: Surgical Technique

BACKGROUND

Robot-assisted radical prostatectomy (RARP) involves a tradeoff between oncological control and functional outcomes. Intraoperative control of surgical margins (SMs) may help in ensuring the safety of the dissection. Fluorescence confocal microscopy (FCM) is an effective method for interpretation of prostate tissue and provides digital images with an appearance similar to hematoxylin-eosin staining.

OBJECTIVE

To describe an alternative technique to NeuroSAFE for intraoperative evaluation of neurovascular-adjacent margins shaved from ex vivo specimens using FCM analysis.

DESIGN, SETTING, AND PARTICIPANTS

This was a prospective study of 24 patients undergoing RARP with intraoperative FCM control of margin status.

SURGICAL PROCEDURE

After surgical dissection, SMs are sectioned from the fresh prostate using the Mohs technique (shaving): three slices from the apex and the right and left posterolateral aspects are obtained. Digital images of the shavings are immediately acquired via FCM and shared with a remote pathologist. In the case of a positive SM, a focal secondary resection of the bundle can be performed owing to the ability of FCM to locate a region of interest on the flat sample.

MEASUREMENTS

The primary outcome measure was the rate of negative margins at neurovascular-adjacent sites. Oncological and functional outcomes for patients with 1 yr of follow-up are also reported.

RESULTS AND LIMITATIONS

All patients had negative SMs in shavings from neurovascular-adjacent areas at final histopathology; four underwent a secondary resection with final conversion to negative SM status. Nine of ten patients with 1-yr follow-up are free of biochemical recurrence (prostate-specific antigen persistence in one pN1 case), nine are fully continent, and four of the five with preoperative potency have recovered their sexual function.

CONCLUSIONS

Digital frozen sections with FCM during RARP may represent an alternative to NeuroSAFE for possible optimization of functional outcomes without compromising oncological safety.

PATIENT SUMMARY

We developed a technique to ensure complete removal of cancer tissue during surgical removal of the prostate. Tissue specimens are examined via digital microscopy in real time during the operation. This allows the surgeon to remove more tissue if cancer is detected at the margins of a specimen, while avoiding unnecessary removal of healthy tissue.

Utility of teledermatopathology for intraoperative margin assessment of melanoma in situ, lentigo maligna type: A 6 year community practice experience

BACKGROUND

Achieving negative margins for melanoma in situ, lentigo maligna type can be challenging, particularly on cosmetically sensitive areas.

OBJECTIVE

To assess the utility of intraoperative frozen section margin assessment using a teledermatopathology system in the treatment of head and neck lentigo maligna.

METHODS AND MATERIALS

Over a 6 year period, 96 patients with lentigo maligna had surgical excisions. The margins were assessed intraoperatively with frozen sections prepared in the manner used in Mohs surgery. The surgeon guided the frozen section slides around the margin while a dermatopathologist assessed the margin remotely.

RESULTS

In 2/96 (2.1%) cases, the safety margin was positive (frozen sections were false negative). In 1 further case (1%) there was a recurrence of the melanoma 13 months following the excision.

CONCLUSION

The described method is effective in treating melanoma in situ, lentigo maligna type with clearance rates similar to previous studies for Mohs surgery.

Comparison of two intraoperative examination methods for the diagnosis of sentinel lymph node metastasis in clinically early stage endometrial cancer: A Turkish Gynecologic Oncology Group Study (TRSGO-SLN-003)

OBJECTIVE

This study evaluated diagnostic accuracy of intraoperative sentinel lymph node (SLN) frozen section examination and scrape cytology as a possible solution for management of SLN positive patients.

STUDY DESIGN

Clinically early-stage endometrial cancer patients who underwent SLN algorithm and intraoperative SLN examination were analyzed. Findings were compared with final pathology results and diagnostic accuracy of frozen section and scrape cytology were evaluated.

RESULTS

Of the 208 eligible patients, 100 patients (48 %) had frozen section examination and 108 (52 %) had scrape cytology of the SLN. Intraoperative examination and final pathology were negative for metastasis in 187/208 (90 %) cases. The rest 21 cases had metastatic SLNs according to final pathology. 12 of 21 (57 %) metastases were classified as macrometastasis. Intraoperative examination of SLNs correctly identified 13 cases (true positive) and missed 8 cases (false negative). Five of 8 false negative cases had micrometastasis or isolated tumor cells. Considering identification of macrometastasis, sensitivity and negative predictive value were 85.71 % and 98.94 %, respectively, for the frozen section and 60.00 % and 98.15 %, respectively, for the scrape cytology.

CONCLUSION

Frozen section examination of SLN has higher sensitivity in detecting macrometastasis compared to scrape cytology and it could help the surgeon in decision for further lymphadenectomy intraoperatively.

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.

Diagnostic pitfall of thyroid fine-needle aspiration induced fibrosis: follicular adenoma mimicking medullary thyroid carcinoma in frozen section

Background

Fine-needle aspiration (FNA) is a frequently utilized method for the diagnosis of thyroid nodules. Although the technique has clear advantages, the injury caused by the aspiration needle can induce various histological alterations. Herein, we report a case of follicular adenoma showing histological alterations possibly caused by FNA biopsy. Furthermore, the histological appearance of the lesion mimicked those of medullary thyroid carcinoma, particularly in the frozen section.

Case presentation

Ultrasonography of a thyroid nodule in a 39-year-old man revealed a mass (2.2 cm in diameter) in the right thyroid lobe. FNA was performed three times on the mass, and the results of the cytology were atypia of undetermined significance. Thereafter, the patient underwent right hemithyroidectomy. The histological findings of the operative frozen section analysis indicated medullary thyroid carcinoma. However, after evaluation and immunohistochemical staining of the permanent section, the mass was diagnosed as follicular adenoma with extensive fibrosis.

Conclusion

The histological alterations observed in the follicular adenoma are believed to have been caused by injury during the repeated FNA procedures.

Roles of Pathological Assessments of Frozen Sections in Esophageal Squamous Cell Carcinoma

Pathological assessment of frozen sections of tissues is important in the clinical management (intraoperative consultation) and research in patients with esophageal squamous cell carcinoma. Frozen sections may be used in the assessment of status of resection margins, extent of cancer metastasis (pathological staging), confirmation of the pathology, and increased volume of cancer cells for tissue banking. However, the applications of frozen sections have many technical limitations. Thus, interpretation of frozen sections needs expertise, collaborations, and attention to proper technical skills in the sectioning.

Stimulated Raman Histology for Rapid Intraoperative Diagnosis of Gliomas

BACKGROUND

Intraoperative pathologic diagnosis traditionally involves frozen section histopathology, which may be labor and time intensive. Indeed, a technique that streamlines the acquisition and evaluation of intraoperative histologic data may expedite surgical decision-making and shorten operative time. Stimulated Raman histology (SRH) is an emerging technology that allows for more rapid acquisition and interpretation of intraoperative histopathologic data.

METHODS

A blinded, prospective cohort study was performed for 82 patients undergoing resection for a central nervous system tumor. Of these, 21 patients were diagnosed with glioma either intraoperatively or postoperatively on permanent section histology and included in this study. Time to diagnosis (TTD) and diagnostic accuracy relative to permanent section (the gold standard) were compared between SRH-based diagnosis and conventional frozen section histology. Diagnostic concordance with permanent section was also compared between frozen histopathology and SRH diagnosis.

RESULTS

Diagnostic accuracy was not significantly different between methods (P = 1.00). Diagnostic concordance was not significantly different between methods when comparing 95% confidence intervals for kappa values (κ = 0.215; κ = 0.297; κ = 0.369). Lastly, mean TTD was significantly shorter with SRH-based diagnosis compared with frozen section (43 vs. 9.7 minutes, P < 0.0001). SRH was able to identify key features associated with varying glioma types.

CONCLUSIONS

SRH allows for rapid intraoperative diagnosis without sacrificing diagnostic accuracy. SRH may serve as a promising adjuvant to conventional histopathology to expedite intraoperative pathology consultation and surgical decision-making.

Is the Use of Intraoperative Frozen Section During Pancreaticoduodenectomy Justified?

BACKGROUND

Intraoperative frozen section (IFS) is routinely utilized by many surgeons during pancreaticoduodenectomy. However, its utility has not been rigorously studied.

METHODS

Patients who underwent pancreaticoduodenectomy between 2006 and 2015 were identified from institutional data. Measures of diagnostic accuracy of frozen section and multivariate logistic regression are reported.

RESULTS

The cohort included 1076 patients. Of resected specimens, 73.3% were malignant. IFS and final pathologic review (the gold standard) were discrepant for (1) pathologic diagnosis or (2) resection margin status in 5.3% and 3.3% of cases. The sensitivity, specificity, and accuracy of IFS for histologic determination of malignancy were 97.2%, 95.3%, and 96.7% respectively. For resection margins, they were 92.3%, 99.3%, and 96.8%, respectively. Positive bile duct and neck margins were revised intraoperatively 62% and 65% of the time, respectively; positive uncinate margins were never resected but led surgeons to avoid revision of a second positive margin in 13% of cases (4.2% of all PDA). Operative changes were rarely noted in the presence of benign disease (n = 11, 1.0%); conversion to total pancreatectomy based on positive margins was performed in just 13 cases (1.2%). Upon multivariable analysis, a positive neck margin proved to be the greatest predictor for a revised resection margin (AOR 16.9 [4.8-59.8]), whereas a positive uncinate margin or a diagnosis of chronic pancreatitis was protective against IFS-driven operative changes (AOR 0.25 [0.09-0.73]; AOR 0.16 [0.13-0.19]).

CONCLUSIONS

IFS is highly accurate and guides reresection of margins. However, selective omission of IFS may be justified for cases where benign disease is suspected.

Rapid Intraoperative Diagnosis of Meningiomas using Stimulated Raman Histology

BACKGROUND

Frozen section is a time- and labor-intensive method for intraoperative pathologic diagnosis. As a result, there exists a need to expedite and streamline the acquisition and interpretation of diagnostic histologic data to inform surgical decision making. Stimulated Raman histology (SRH) is an emerging technology that may serve to expedite the acquisition and interpretation of histologic data in the operating room.

METHODS

A blinded, prospective cohort study of 82 patients undergoing resection for tumors of the central nervous system was performed. Twenty-six patients with diagnoses of meningioma on SRH, frozen, or permanent section were included in this subanalysis. Diagnostic time and accuracy of stimulated SRH histology images were compared with the gold standard (frozen section). Agreement of SRH and frozen section diagnosis with permanent section (true) diagnosis was also compared.

RESULTS

Mean time-to-diagnosis was significantly shorter for SRH-mediated diagnosis compared with frozen section (9.2 vs. 35.8, P < 0.0001). Diagnostic accuracy was not significantly different between methods (P = 0.15). Diagnostic agreement was not significantly different between SRH versus frozen, SRH versus permanent, or frozen versus permanent section methods (P = 0.5, P = 0.5, P = 1.00).

CONCLUSIONS

SRH is a promising adjuvant technology that may expedite intraoperative neuropathologic consult without sacrificing diagnostic accuracy.

Is there a Role for Frozen Section Evaluation of Parotid Masses After Preoperative Cytology or Biopsy Diagnosis?

Fine-needle aspiration (FNA) biopsy reliably diagnoses parotid gland lesions preoperatively, whereas intraoperative frozen section (FS) has the additional benefit of assessing surgical margins and refining diagnoses; however, the role of FS in the setting of prior FNA diagnosis is not well established. Our aim was to determine whether FS should still be performed after a prior FNA/ CNB diagnosis. Parotid gland resections from January 2009 to January 2020 were identified; however, only patients who had both FNA and FS constituted our study population. For the purpose of statistical analysis, FNA diagnoses were classified into non-diagnostic (ND), non-neoplastic (NN), benign neoplasm (BN), indeterminate, and malignant. FS diagnoses were classified into benign, indeterminate, or malignant. Resections were dichotomized into benign and malignant and regarded as the gold standard to subsequently calculate diagnostic accuracy of FNA and FS. A total of 167 parotid gland resections were identified, but only 76 patients (45.5%) had both FNA and FS. In 35 cases deemed as benign preoperatively, three (8.6%) were reclassified as malignant on FS. Out of 18 lesions reported as malignant on FNA, four (22.2%) were interpreted as benign on FS, with three of these benign lesions confirmed on permanent slides. In addition, in patients with both FNA and FS, compared to FNA, FS was able to provide a definitive diagnosis in all five ND cases and in 61.1% (11/18) of indeterminate tumors. Intraoperative assessment provided a relative increase of 33.3% in specificity and 38.5% in positive predictive value when compared to preoperative FNA. The addition of FS to FNA was helpful to further refine the diagnoses of parotid gland lesions, which may provide better guidance for surgical intervention.

Accuracy of intra-operative frozen section in guiding surgical staging of endometrial cancer

PURPOSE

Surgery consists the main treatment of endometrial cancer; however, decision of lypmhadenectomy is controversial. Intra-operative frozen section (FS) is commonly used in guiding surgical staging; nevertheless, there are different reports regarding its adequacy and reliability. Aim of this study is to assess accuracy of FS in predicting paraffin section (PS) results in patients with endometrium cancer.

METHODS

Data of 223 cases, who were operated for endometrial cancer at a tertiary hospital in 2012-2019, were analyzed retrospectively. Histological type, grade, tumor diameter, depth of myometrial invasion, and cervical and adnexal involvement in frozen and paraffin section were evaluated. Positive and negative predictive values and accuracy of frozen results in predicting paraffin results for each parameter was assessed. Statistical significance was taken as 0.05 in all tests.

RESULTS

Accuracy of FS in predicting PS results were 76.23% for histology, 75.45% for grade, 85.31% for depth of myometrial invasion, and 95.45% for tumor diameter. Surgery, based on FS results, caused undertreatment in 4 patients, while metastatic lymph node ratios were found in only 35.3-50.0% of cases who had high risk parameters at FS.

CONCLUSION

Our FS results have reasonable accuracy rates in predicting PS results, in comparison with the previous literature. However, even if the high risk parameters detected in FS predict PS accurately, absence of lymph node involvement in all cases with high risk parameters indicates that FS-based triage cannot prevent unnecessary lymphadenectomies.

Achieving disease free distal ureteral margin at the time of radical cystectomy: Why and for whom? (an overview of literature)

OBJECTIVE

Achieving negative status of distal ureteral margin at the time of radical cystectomy (RC), and its therapeutic benefit, remains controversial. The aim of this review was to evaluate frequency, reliability and impact of positive distal ureteral margin after radical cystectomy for bladder cancer on upper tract recurrence, cancer specific and overall survival, and to identify best candidates for intraoperative frozen section analyses.

MATERIAL AND METHODS

A systemic review was performed following the PRISMA guideline. PubMed/Medline (with following terms; bladder cancer or cystectomy and frozen section or ureteral margin), and Cochrane Library were searched up to April 2020, to identify all papers evaluating distal ureteral margin and discussing clinical interest. Previous reviews and single case reports were excluded.

RESULTS

In total, thirty-two relevant studies were identified. Mean rate of positive ureteral frozen section after RC was close to 10% [1.1-25.4%]. Frozen section (FS) achieved a very good specificity [83-100%] and reserved sensibility [45-100%]. In many cases, an initial positive margin on FS can be converted to negative. Positive FS and/or PS (permanent section) were associated with upper urinary tract recurrence (UUTR). Conversion from positive FS to negative PS was associated with low UUTR frequency and better cancer survival in large retrospective studies. The relevant prognostic factor associated with positive FS and/or PS was CIS within the bladder.

CONCLUSION

FS should be recommended for patients with CIS within the bladder. Achieving negative FS/PS might be associated with lower rates of UUTR and better survival, for patients with higher life expectancy. Prospective randomized controlled studies need to be performed to provide definitive recommendations in this area.

Acute Invasive Fungal Sinusitis: A 30-Year Review of Pathology Practice and Possible Utility of the DiffQuik® Stain

Acute invasive fungal rhinosinusitis (AIFRS) is a fulminant disease with a high mortality rate. Here, we review the clinical and pathologic features of AIFRS over a 30-year period at a tertiary-care academic center focusing on diagnostic practice, especially the use of intra-operative consultation (IOC). A 1-year trial of intraoperative staining with DiffQuik® (DQ) was also assessed. There were 202 cases from 104 patients with AIFRS. The incidence of AIFRS increased over time (6.8 per year in the past decade versus 1.9 before 2009) as did the number of IOCs per case (2.4 per case in the past decade versus 0.6 before 2009). Disagreement between final diagnosis and IOC was seen in 8.3 % of patients, and the block-by-block error rate was 14.9 %. Fusarium was the most common fungus identified. An attempt to categorize the fungal organism based on histopathology was performed in 85.6 % of patients, with 91 % agreement with microbial cultures or PCR. Fungal hyphae were subjectively easier to identify on DQ stained cryostat sections compared to on routine hematoxylin and eosin stained sections and hyphae were identified in all 5 blocks in which organisms were present. The increasing incidence of AIFRS and expanding use of IOC indicate a need to improve and standardize the diagnostic protocol. The use of DQ as visual aid in IOC for AIFRS may be useful.

Patients with no recurrence of infection five years after two-stage revision hip arthroplasty may be classified as periprosthetic infection 'in remission'

AIMS

We aimed to report the mid- to long-term rates of septic and aseptic failure after two-stage revision surgery for periprosthetic joint infection (PJI) following total hip arthroplasty (THA).

METHODS

We retrospectively reviewed 96 cases which met the Musculoskeletal Infection Society criteria for PJI. The mean follow-up was 90 months (SD 32). Septic failure was assessed using a Delphi-based consensus definition. Any further surgery undertaken for aseptic mechanical causes was considered as aseptic failure. The cumulative incidence with competing risk analysis was used to predict the risk of septic failure. A regression model was used to evaluate factors associated with septic failure. The cumulative incidence of aseptic failure was also analyzed.

RESULTS

There were 23 septic failures at final follow-up, with a cumulative incidence of 14% (95% confidence interval (CI) 8% to 22%) at one year, 18% (95% CI 11% to 27%) at two years, 22% (95% CI 14% to 31%) at five years, and 23% (95% CI 15% to 33%) at ten years. Having at least one positive culture (hazard ratio (HR) 2.38 (interquartile range (IQR) 1.19 to 4.74); p = 0.013), or a positive intraoperative frozen section (HR 2.55 (IQR 1.06 to 6.15); p = 0.037) was significantly associated with septic failure after reimplantation. With dislocation being the most common cause of aseptic revision (5.2%), the cumulative incidence of aseptic failure was 1% (95% CI 0% to 5%) at one year, 6% (95% CI 1% to 8%) at five years, and 8% (95%CI 3% to 17%) at ten years.

CONCLUSION

If there is no recurrent infection in the five years following reimplantation, the chances of further infection thereafter are remote. While the results of a frozen section may be a reliable guide to the timing of reimplantation, intraoperative culture has, currently, only prognostic value. Surgeons should be aware that instability remains a potential indication for further revision surgery. Cite this article: Bone Joint J 2021;103-B(1):79-86.

Effects of brain tissue section processing and storage time on gene expression

The pre-processing of samples is important factors that affect the results of the RNA-sequencing (RNA-seq) data. However, the effects of frozen sections storage conditions on the integrity of RNA and sequencing results haven't been reported. The study of frozen section protection schemes can provide reliable experimental results for single-cell and spatial transcriptome sequencing. In this study, RNA was isolated to be studied for RNA from brain section at different temperatures (RT: room temperature, -20 °C) and storage time (0 h, 2 h, 4 h, 8 h, 12 h, 16 h, 24 h, 7day, 3week, 6month). The stability of reference genes was validated using reverse transcription quantitative real-time polymerase chain reaction (qRT-PCR). The results showed that the storage at room temperature significantly affected RNA integrity number (RIN), and the RIN value was lower with the prolongation of storage, while the storage at -20 °C exerted less effect on the RIN value. Cresyl violet staining for brain tissue sections had little effect on RNA integrity. 1925, 899 and 3390 differential expression genes (DEGs) were screened at 2 h, 4 h and 8 h at room temperature, respectively. A total of 892, 478 and 619 genes were shown to be differentially expressed at -20 °C for 7d, 3w and 6 m, respectively. Among them, the expression of glycoprotein m6a (Gpm6a), calmodulin 1 (Calm1), calmodulin 1 (Calm2), thymosin, beta 4, X chromosome (Tmsb4x), ribosomal protein S21 (Rps21) and so on were correlated with RNA quality. According to the expression stability of 4 reference genes (Actb: beta-actin; Gapdh: glyceraldehyde-3-phosphate dehydrogenase; 18S: 18S ribosomal; Hprt1: hypoxanthine phosphoribosyltransferase 1), 18S is the most stable reference gene in the brain. In conclusion, the storage temperature and time of frozen sections have significant effects on RNA integrity and sequencing results. But there are still some genes that are stable and not affected by worsening of overall RNA integrity ie the decrease of RIN value. In addition, 1% cresyl violet staining can protect RNA.

Improved survival after pancreatic re-resection of positive neck margin in pancreatic cancer patients. A systematic review and network meta-analysis

The oncological benefit of achieving a negative pancreatic neck margin through re-resection after a positive frozen section (FS) is debated. Aim of this network meta-analysis is to evaluate the survival benefit of re-resection after intraoperative FS neck margin examination following pancreatectomy for ductal adenocarcinoma. A systematic search of studies comparing different strategies for the management of positive FS was performed. Patients were classified in three groups based on FS and permanent section (PS): Group A (FS-, PS-R0), Group B (FS+, PS-R0), Group C (FS±, PS-R1). A frequent random-effects network-meta-analysis was made reporting the surface under the cumulative ranking (SUCRA). Primary endpoint was overall survival (OS). Secondary endpoints were pathological outcomes. Seven retrospectives studies with 4205 patients were included and 99.1% of the pancreatic resections were pancreatoduodenectomies. Group A had the highest probability of better OS (SUCRA = 90%), compared to Group B (SUCRA = 48.7%) and Group C, which was the worst prognostic scenario (SUCRA = 11.3%). Group B had still a probability of longer OS compared to Group C (SUCRA = 48.7% vs 11.3%). Pathological features were more favourable in Group A, with the highest SUCRA for T1-T2 tumors (92.6%), N0 status (89.4%), absence of perineural invasion (92.3%). Heterogeneity was low (τ-value <0.1) for OS, and moderate (τ-values: 0.1-0.6) for pT, pN, and perineural invasion. In conclusion, negative neck margin after primary resection (FS negative) or re-resection of a positive FS was associated with improved survival compared with PS-R1. However, any intraoperative positive FS can be considered as a prognostic factor associated with a more aggressive disease.

Matrix-Assisted Laser Desorption/Ionization-Mass Spectrometry Imaging of Lipids in the Ischemic Rat Brain Section: A Practical Approach

Matrix-assisted laser desorption/ionization-mass spectrometry imaging (MALDI-MSI) of lipids is considered one of the shotgun lipidomic techniques that explores the in situ distribution of lipids in tissue sections. To successfully perform this task, knowledge and experience in the conventional cryosection, tissue section collection and handling, and mass spectrometry data analysis and signal processing are needed. A MALDI-MSI protocol covering from the fresh organ collection, cryosection and tissue processing, matrix application, MSI data acquisition, to the final MSI display of lipid distribution in the brain section of an ischemic stroke rat is described to exemplify this technique. Due to the multidisciplinary nature of this approach, plenty of preparation, practice, and familiarization to several critical steps ahead of the engagement with actual biological samples are needed to ensure a successful MALDI-MSI presentation of lipids in situ.

Accuracy and Reproducibility of Intraoperative Assessment on Tumor Spread Through Air Spaces in Stage 1 Lung Adenocarcinomas

INTRODUCTION

Tumor spread through air spaces (STAS) is associated with worse prognosis in early-stage lung adenocarcinomas, particularly in sublobar resection. Intraoperative consultation for STAS has been advocated to guide surgical management. However, data on accuracy and reproducibility of intraoperative assessment of STAS remain limited. We evaluated diagnostic yield, interobserver agreement (IOA), and intraobserver agreement (ITA) for STAS detection on frozen section (FS).

METHODS

A panel of three pathologists evaluated stage 1 lung adenocarcinomas (n = 100) for the presence or absence of STAS and artifacts as reference. Five pulmonary pathologists independently reviewed all cases in two rounds, detecting STAS and artifacts in FS and the corresponding FS permanent and non-FS permanent, with a consensus conference between rounds.

RESULTS

The FS had low sensitivity (44%), high specificity (91%), relatively high accuracy (71%), and overall area under the receiver operating characteristic curve of 0.67 for detecting STAS. The average ITA was moderate for both STAS (κ_mean: 0.598) and artifact (κ_mean: 0.402) detection on FS. IOA was moderate for STAS (κ_round-1: 0.453; κ_round-2: 0.506) and fair for artifact (κ_round-1: 0.300; κ_round-2: 0.204) detection on FS. IOA for STAS improved in FS permanent and non-FS permanent, whereas ITA was similar across section types. On multivariable logistic regression, the only significant predictor of diagnostic discordance was the presence of artifacts.

CONCLUSIONS

FS is highly specific but not sensitive for STAS detection in stage 1 lung adenocarcinomas. IOA on STAS is moderate in FS and improved only marginally after a consensus conference, raising concerns regarding global implementation of intraoperative assessment of STAS and warranting more precise criteria for STAS and artifacts.

Does diagnostic accuracy of surgeon's perception outweigh frozen section analysis in determining intraoperative clear mucosal surgical margins in oral squamous cell carcinoma patients?

Introduction:

The lucrativeness of the frozen section for intraoperative margin assessment in head and neck squamous cell carcinoma is debatable till date. The purpose of this study was to evaluate whether surgeon's perception by gross examination (GE) of margin is an alternative to frozen section.

Aim:

The aim was to compare the diagnostic accuracy (DA) of surgeon's perception of tumor-free mucosal and soft-tissue surgical margins intraoperatively assessed by GE and frozen section analysis (FSA).

Methodology:

A prospective, observational study was conducted on 59 histologically proven cases of oral squamous cell carcinoma. Two hundred and thirty-six mucosal margins were assessed by an experienced surgeon (ES) and thereafter subjected subsequently to FSA. These results were compared with the gold standard histopathology (HPE). The sensitivity (SS), specificity (SP), positive predictor value (PPV), negative predictor value (NPV), and DA of surgeon's perception by GE were calculated and subsequently compared with FSA and HPE using descriptive and inferential statistics.

Results:

The SS, SP, PPV, NPV, and DA of ES by GE were 80%, 99.12%, 80%, 99.12%, and 98.30%, respectively when compared to HPE, and the SS of 90%, SP of 98.32%, PPV, NPV, and DA were 69.23%, 99.57%, and 97.98%, respectively when compared with HPE. The results of the surgeon's perception by GE were comparable to the results of FSA.

Conclusion:

The study concludes that surgeon's perception by GE is upfront reliable alternative intraoperative method to FSA in places where FS is not available.

Frozen section in thyroid gland follicular neoplasms: It's high time to abandon it!

Thyroid nodules are a very common clinical condition. The 2015 American Thyroid Association (ATA) guidelines recommend surgical excision for Bethesda IV nodules. The use of intraoperative frozen section (FS) has been recommended as a strategy to tailor the extent of the initial surgery. We critically evaluated the literature that discusses the utility and cost-effectiveness of FS to make an intraoperative decision in patients with thyroid nodules classified as follicular neoplasm. FS should not be recommended as a routine intraoperative test to assess for malignancy in thyroid follicular patterned lesions due to its low performance; the high number of deferred results; the inability to adequately assess histologically defining features; the improvements in risk stratification guiding total thyroidectomy; and the low cost-effectiveness of FS.

Factors associated with discrepancy between fresh frozen and permanent biopsy from medical thoracoscopy: single center analysis of 172 medical flexible thoracoscopy cases

Background

Frozen sections prepared during medical thoracoscopy (MT) have precise diagnostic ability in pleural pathology and may assist in decision-making before pleurodesis. The present study evaluated the diagnostic sensitivity of frozen sections from flex-rigid MT, and further evaluated clinical parameters for their association with a discrepancy between frozen sections and permanent paraffin sections.

Methods

This retrospective study evaluated 172 patients who underwent flex-rigid MT between February 2017 and November 2019 at Incheon Saint Mary's Hospital.

Results

Of the 172 patients, 85 were pathologically diagnosed with malignancy based on permanent paraffin sections. An accurate diagnosis by fresh frozen section was feasible in 88.2% of the cases compared to the permanent paraffin sections. Among the 85 patients, 75 had malignancies in frozen sections, while 10 patients showed otherwise. In the 85 malignant cases, age, sex, the volume of effusion, thoracoscopic findings, as well as the final pathological diagnosis (lung vs. non-lung origin) were included in univariate analysis for an association with non-malignant frozen section results. High adhesion grade and malignancy other than lung cancer were significant factors associated with frozen section negative cases in a multivariable analysis.

Conclusions

Taking fresh frozen sections during MT using a flex-rigid bronchoscope is a useful diagnostic modality with reliable sensitivity for malignancy. However, if the pre-procedural diagnosis is likely to be a malignancy other than lung cancer, and if severe adhesions are present in the pleural cavity, the final pathological confirmation should be determined based on permanent paraffin sections, not only on fresh frozen sections.

Improved detection of sentinel lymph node metastases allows reliable intraoperative identification of patients with extended axillary lymph node involvement in early breast cancer

An improved procedure that allows accurate detection of negative sentinel lymph node (SLN) and of SLN macrometastases during surgery would be highly desirable in order to protect patients from further surgery and to avoid unnecessary costs. We evaluated the accuracy of an intraoperative procedure that combines touch imprint cytology (TIC) and subsequent frozen section (FS) analysis. 2276 SLNs from 1072 patients with clinical node-negative early breast cancer were evaluated during surgery using TIC. Only cytologically-positive SLN were subsequently analysed with a single FS, preserving cytologically-negative SLN for the final postoperative histological diagnosis. Sensitivity, specificity and the accuracy of this approach were analysed by comparing the results from intra- and postoperative SLN and axillary node evaluation. This intraoperative method displayed 100% specificity for SLN metastases and was significantly more sensitive for prognostically relevant macrometastases (85%) than for micrometastases (10%). Sensitivity was highest for patients with two or more positive LNs (96%) than for those with only one (72%). 98% of the patients with final pN2a-pN3a were already identified during surgery. Patients who received primary axillary lymph node dissection had significantly more frequent metastases in further LNs (44.6%). Sensitivity was highest for patients with luminal-B, HER2+ and triple negative breast cancer and for any subtype if Ki-67 > 40%. TIC and subsequent FS of cytologically-positive SLNs is highly reliable for detection of SLN macrometastases, and allows accurate identification of patients with a high risk of extended axillary involvement during surgery, as well as accurate histological diagnosis of negative SLN.