When does skin excision allow the achievement of an adequate local control rate in patients with squamous cell carcinoma involving the buccal mucosa?

Should sub-millimeter margins be deemed positive in oral cavity squamous cell carcinoma?

BACKGROUND

While several studies have indicated that a margin status of < 1 mm should be classified as a positive margin in oral cavity squamous cell carcinoma (OCSCC), there is a lack of extensive cohort studies comparing the clinical outcomes between patients with positive margins and margins < 1 mm.

METHODS

Between 2011 and 2020, we identified 18,416 Taiwanese OCSCC patients who underwent tumor resection and neck dissection. Of these, 311 had margins < 1 mm and 1013 had positive margins. To compare patients with margins < 1 mm and those with positive margins, a propensity score (PS)-matched analysis (n = 253 in each group) was conducted.

RESULTS

The group with margins < 1 mm displayed a notably higher prevalence of several variables: 1) tongue subsite, 2) younger age, 3) smaller depth of invasion), 4) early tumor stage, and 5) treatment with surgery alone. Patients with margins < 1 mm demonstrated significantly better disease-specific survival (DSS) and overall survival (OS) rates compared to those with positive margins (74 % versus 53 %, 65 % versus 43 %, both p < 0.0001). Multivariable analysis further confirmed that positive margins were an independent predictor of worse 5-year DSS (hazard ratio [HR] = 1.38, p = 0.0103) and OS (HR = 1.28, p = 0.0222). In the PS-matched cohort, the 5-year outcomes for patients with margins < 1 mm compared to positive margins were as follows: DSS, 71 % versus 59 %, respectively (p = 0.0127) and OS, 60 % versus 48 %, respectively (p = 0.0398).

CONCLUSIONS

OCSCC patients with a margin status < 1 mm exhibited distinct clinicopathological characteristics and a more favorable prognosis compared to those with positive resection margins.

Neoadjuvant chemotherapy in technically unresectable head and neck cancers: a retrospective audit

Background

The data regarding the use of neoadjuvant chemotherapy in technically unresectable head and neck cancer (HNC) is limited and real-world studies are needed to look for the efficacy and toxicities of this approach.

Patients and methods

This is a retrospective study conducted in the Medical Oncology department of our hospital. All technically unresectable HNC patients who underwent neoadjuvant chemotherapy between May 2018 and May 2020 were included in this analysis. Patients received three-drug regimen docetaxel, cisplatin and 5-fluorouracil (DCF) regimen, two-drug regimens included docetaxel + cisplatin, paclitaxel + carboplatin both weekly and 3-weekly. The resectability assessment was done clinically and radiologically after completing three neoadjuvant cycles. Overall survival was calculated from the first day of chemotherapy to the date of last follow-up or date of death.

Results

A total of 119 patients received neoadjuvant chemotherapy during the specified time. Response assessment showed partial response in 41.9% of patients with three-drug regimens and 37.5% of patients with other regimens. Out of 119 patients, 56 (47%) patients were offered radical intent therapy. Resectability was achieved in 32.3% of three-drug regimen patients and 26.1% of other patients. Surgery was feasible in 33 (27.7%) patients, and postoperative radiotherapy and concurrent chemotherapy were done in 30 patients (25.2%), and surgery with only postoperative radiotherapy was done in 3 patients (2.5%). Radical chemoradiotherapy was done in 23 patients (19.3%). The estimated median survival for patients who could undergo surgery was 18 months [95% confidence interval (CI), 14.9-21.0], and nonsurgical patients were 9 months (95% CI, 7.3-10.6) (p = 0.0001).

Conclusion

Our study shows that neoadjuvant chemotherapy in technically unresectable HNC patients can make the disease resectable in around one-third of the patients. The patients who could undergo surgery after neoadjuvant chemotherapy had significantly improved survival as compared to those who could not.

Lateral skull base surgery for posterior oral cavity cancer

The aim of this study was to better understand posterior oral cavity cancer (POCC) and its surgical treatment. This was a retrospective study of 76 patients who were diagnosed with POCC and underwent surgical treatment. Twenty-eight patients were treated with anatomical unit resection surgery (AURS) and 48 patients with conventional surgery. After initial treatment with curative intent, the patients were followed-up regularly with clinical examinations and imaging; the median duration of follow-up was 30.9 months (range 2-67 months). The 3-year overall survival was 64.3% in the experimental AURS group and 39.6% in the conventional surgery control group (hazard ratio 0.49, 95% confidence interval 0.26-0.93; P=0.031). The 3-year disease-free survival was 64.3% in the experimental group and 37.5% in the control group (hazard ratio 0.53, 95% confidence interval 0.27-1.02; P=0.114). In conclusion, AURS is an effective surgical treatment for POCC that can considerably improve patient survival rates.

A prospective study of intraoperative assessment of mucosal squamous cell carcinoma margins in the head and neck

BACKGROUND

In head and neck cancers, tumor margin assessment has important prognostic and therapeutic implications. Frozen section control of margins is commonly employed intraoperatively. However, this is not without limitations. The aim of this study is to determine whether intraoperative slicing of the whole specimen is feasible and what impact this may have on tumor margin assessment and the requirement for postoperative radiotherapy.

METHODS

From September 2016 to August 2018, we recruited 22 patients as a pilot study looking at both the practicalities and the clinical relevance of whole margin tumor analysis intraoperatively. Our project is a prospective single arm study with historical controls.

RESULTS

Forty-one percent of our patients required further intraoperative resection for close or involved margins. Seven of these patients who otherwise would have required adjuvant radiotherapy due to their margin status did not, after our intervention.

CONCLUSIONS

We found that although requiring resources, this process was feasible without unduly increasing operative times and with potential patient benefit including reduced incidence of adjuvant radiotherapy.

Contemporary Approach to Locally Advanced Oral Cavity Squamous Cell Carcinoma

PURPOSE OF REVIEW

Surgical management of locally advanced oral cavity squamous cell carcinomas (OCSCC) has long been recognized as a primary treatment modality. Technological advances have led to significant improvements in our surgical approach, from improvement in the visualization of tumors to more efficient and precise reconstruction. Here, we review the latest technological advances in surgical extirpation and reconstruction of locally advanced OCSCCs.

RECENT FINDINGS

The focus of technological innovation in surgical extirpation has been on improving visualization, with the use of intraoperative ultrasound for margin delineation, intraoperative navigation, narrow-band imaging, and the use of fluorescence. Though early, these are promising steps to ensuring complete resection of the cancer. Advances in reconstruction have been centered on the incorporation of computer assisted design, manufacturing, and virtual surgical planning, allowing for more complex three-dimensional defects to be expeditiously reconstructed. As these technologies are still under development, their impact on oncologic outcomes are not yet robustly defined; however, as technology continues to advance and become more widely available, new technologies will undoubtedly become integrated into enhancing surgical precision and planning.

Guidelines for the Surgical Management of Oral Cancer: Korean Society of Thyroid-Head and Neck Surgery

Korean Society of Thyroid-Head and Neck Surgery appointed a Task Force to provide guidance on the implementation of a surgical treatment of oral cancer. MEDLINE databases were searched for articles on subjects related to “surgical management of oral cancer” published in English. Results were restricted to systematic reviews, randomized control trials/controlled clinical trials, and observational studies. The quality of evidence was rated with use RoBANS (Risk of Bias Assessment Tool for Nonrandomized Studies) and AMSTAR (A Measurement Tool to Assess the Methodological Quality of Systematic Reviews). Evidence-based recommendations for practice were ranked according to the American College of Physicians grading system. Additional directives are provided as expert opinions and Delphi questionnaire when insufficient evidence existed. The Committee developed 68 evidence-based recommendations in 34 categories intended to assist clinicians and patients and counselors, and health policy-makers. Proper surgical treatment selection for oral cancer, which is directed by patient- and subsite-specific factors, remains the greatest predictor of successful treatment outcomes. These guidelines are intended for use in conjunction with the individual patient’s treatment goals.

Molecular and serologic markers of HPV 16 infection are associated with local recurrence in patients with oral cavity squamous cell carcinoma

Human papillomavirus (HPV) infections predict mortality in Taiwanese patients with oral cavity squamous cell carcinoma (OCSCC). To address their prognostic significance for local recurrence (LR), in this retrospective cohort study we investigated different serologic and molecular markers of HPV 16 infection in 85 consecutive patients with primary OCSCC who received standard treatment and had their sera stored before treatment. Resected tumor specimens were examined with PCR-based assays for HPV 16 E6/E7 mRNA expression. Sera were tested with suspension arrays for the presence of HPV-specific antibodies using synthetic L1 and E6 peptides as well as a synthetic E7 protein. HPV 16 E6/E7 mRNA, anti-L1, anti-E6, and anti-E7 antibodies tested positive in 12%, 25%, 38%, and 41% of the study patients, respectively. Multivariate analysis identified pathological T3/T4, E6/E7 mRNA, and anti-E7 antibodies as independent risk factors for LR, whereas anti-E6 antibodies were an independent protective factor. In patients with ≥ 3 (high-risk group), 2 (intermediate-risk), and ≤ 1 (low-risk) independent risk factors (predictors), the 5-year LR rates were 75%, 42%, and 4%, respectively. Results were validated in an independent cohort. Together, our preliminary data indicate that HPV 16 infections as well as low and high serum levels of anti-E6 and anti-E7 antibodies, respectively, can serve as biomarkers of LR in patients with OCSCC, whereas the clinical usefulness of anti-HPV 16 antibodies for risk stratification of newly diagnosed cases deserves further scrutiny.

Unit resection of buccal squamous cell carcinoma: Description of a new surgical technique

This study characterized the infiltration of primary tumors along the muscles, fascia and spaces of the maxillofacial region in buccal squamous cell carcinoma (BSCC) and suggested a new surgical strategy that is suitable for most stages. Based on the anatomic characteristics and infiltration of the primary tumor a new surgical approach - unit resection buccal surgery (URBS) - was developed. We evaluated this new surgical strategy, across a cohort of 127 BSCCs: 60 cases treated with URBS and 67 cases treated with conventional surgery. Notably there was no statistical difference in the clinicopathological variables between the two groups. After initial treatment with curative intent, the patients were regularly followed-up with clinical examination and imaging. URBS proved suitable for almost all stages of BSCC, and was particularly advantageous for advanced stages of BSCC. At 2 years post-treatment, the rates of overall survival were 83.3% in the URBS group and 60.1% in the conventional surgery group, respectively (hazard ratio 0.38; 95% CI 0.20 to 0.75; P=0.005). Similarly, the rates of disease-free survival were 76.6% and 51.9% in the URBS group and the conventional surgery group, respectively (hazard ratio 0.42; 95% CI 0.23 to 0.75; P=0.003). The principles of URBS are suitable for almost all stages of BSCC, especially advanced stages. URBS may improve the prognosis of BSCC patients.

Buccal Mucosa Elasticity Influences Surgical Margin Determination in Buccal Carcinoma Resection

PURPOSE

Little is known about whether buccal mucosa elasticity influences the determination of surgical margins for buccal carcinomas. This study investigated whether there is a difference in elasticity of the buccal mucosa in patients with buccal carcinoma compared with controls without the disease.

PATIENTS AND METHODS

A case-and-control study comprised of patients with buccal carcinoma and controls without the disease was conducted. In each patient, 2 gutta-percha points were attached to the buccal mucosa horizontally and examined twice by lateral cephalometry, once with the mouth closed and once during maximal mouth opening (MMO). Changes in distance between the gutta-percha points were used as a measurement of buccal elasticity. Information on age, alcohol consumption, betel nut chewing, smoking habits, oral submucosa fibrosis (OSF), temporomandibular joint (TMJ) subluxation, and interincisal distance at MMO (IDMMO) was collected. The results were analyzed using independent-sample and paired-sample t tests.

RESULTS

Ten patients with buccal carcinoma and another 11 patients without buccal carcinoma were enrolled in this study. There was a significant increase in magnification percentage in patients with carcinoma (32.35%; P < .001) during MMO. Magnification of the comparison group during MMO measured 51.55%, also a significant increase (P < .001). Betel nut chewing significantly decreased mucosa elasticity; magnification was 29.20% (P = .013). Magnification was significantly higher in patients with TMJ subluxation (54.50%; P = .041) than in the controls. Age, alcohol consumption, smoking, OSF, and IDMMO did not affect buccal mucosa elasticity.

CONCLUSIONS

Buccal mucosa elasticity increased considerably at MMO in patients with buccal carcinoma. This elasticity should be taken into account when calculating adequate surgical margins for transoral resection of buccal carcinoma.

Pitfalls in determining head and neck surgical margins

Accurate assessment of surgical margins in the head and neck is a challenge. Multiple factors may lead to inaccurate margin assessment such as tissue shrinkage, nonstandardized nomenclature, anatomic constraints, and complex three dimensional specimen orientation. Excision method and standard histologic processing techniques may obscure distance measurements from the tumor front to the normal tissue edge. Arbitrary definitions of what constitutes a "close" margin do not consider the prognostic significance of resection dimensions. In this article we review some common pitfalls in determining margin status in head and neck resection specimens as well as highlight newer techniques of molecular margin assessment.

Site-wise Differences in Adequacy of the Surgical resection Margins in Head and Neck Cancers

Adequacy of surgical resection decided by the margin status is important in attaining a good local control and better survival in Head and neck Cancers. Conventionally, a measured distance between the tumor edge and the cut edge of the specimen is taken as the margin. A margin more than 5  millimeter (mm) is considered clear, less than 5 mm is close and less than one mm is denoted as involved. The concept of this adequacy varies between the different sites and subsites in head and neck. The purpose of this paper is to review the current evidence that describes the adequacy of surgical margin status and their variability among the sites and sub-sites in the head and neck.

Surgical margins in head and neck squamous cell carcinoma: what is 'close'?

The aim of this systematic review is to evaluate the definition of close margin in head and neck squamous cell carcinoma (HNSCC), and its possible prognostic significance. An appropriate string was run on PubMed to retrieve articles discussing the 'close' surgical margin issue in HNSCC. A double cross-check was performed on citations and full-text articles retrieved. In total, 348 articles were identified. Further references were included by using the option "Titles in your search terms" option in PubMed. 15 papers were finally included for qualitative synthesis. In vocal cord surgery of HNSCC, a close margin could be considered to be ≤1 mm, in the larynx ≤5 mm, in the oral cavity ≤4 mm, and in the oropharynx ≤5 mm. In each patient, the choice of extent of close margin should be balanced against general condition, tumor stage, and functional issues to indicate appropriate adjuvant therapy.

Squamous cell carcinoma of buccal mucosa: a 40-year review

PURPOSE

The aim of this study was to analyze the outcome of surgical therapy for buccal squamous cell carcinoma (SCCA) at a single tertiary care institution during a 40-year period.

MATERIALS AND METHODS

A retrospective review was performed by examining the records and pathology of 48 patients with buccal SCCA treated at a single tertiary care institution from 1970 to 2009.

RESULTS

Treatment entailed surgery alone in 18 patients (37.5%) and surgery followed by radiation therapy in 30 patients (62.5%). Composite resection was performed in 17 patients (35.4%), and ipsilateral neck dissections were performed in 37 patients (77.1%). One-year observed actuarial disease-free survival rates were 60%, 46%, 0%, and 40% for T1 through T4, respectively. Univariate analysis revealed increased age as a risk factor for disease recurrence (P = .062), with skin taken and neck dissection not achieving significance (P = .24 and .20, respectively). Multivariate analysis demonstrated age as increasing risk and neck dissection as decreasing risk of recurrence (P = .029 and .023, respectively).

CONCLUSIONS

We report relatively high disease-free survival rates in patients who underwent aggressive resection and neck dissection. Performance of neck dissection and younger age were associated with a favorable prognosis. Performance of neck dissection may decrease the risk of recurrence in primary SCCA of the buccal mucosa. Although through-and-through resection of skin decreased risk of disease recurrence, this difference is not statistically significant (P = .24).