When should patients with T1N0 oral squamous cell carcinoma be considered for elective neck dissection?

AIMS

To identify adverse pathological features (APF) predicting nodal failure in clinically node negative T1 oral squamous cell carcinoma (OSCC).

METHODOLOGY

This study evaluated patients with T1N0 (≤5 mm depth of invasion (DOI) and ≤2 cm diameter) oral cancers from a prospectively maintained database between 1988 and 2020. All patients underwent surgical excision of the primary lesion without neck dissection. Patients underwent three monthly clinical surveillance and salvage neck dissection was performed if nodal relapse was diagnosed.

RESULTS

Overall, 141 patients were included. Nodal relapse was reported in 16/141 (11.3%) patients. Factors impacting regional recurrence-free survival were DOI ≥3 mm (HR: 2.4, P < 0.001), maximum tumour diameter ≥12 mm (HR: 1.1, P = 0.009), perineural invasion (PNI) (HR 7.5, P = 0.002) and poor differentiation (HR 5.3, P = 0.01). Rates of nodal relapse increased from 2% amongst patients with no APFs to 100% for those with four APFs. Patients with two or more APFs had significantly poorer 5-year regional recurrence-free survival (94.8% vs. 56.3%, P < 0.001).

CONCLUSION

Patients with T1N0 OSCC with two or more APFs (DOI ≥3 mm, diameter ≥12 mm, PNI or poor differentiations) should be considered for elective neck dissection.

[French national standard for the treatment of squamous cell carcinoma of upper aero-digestive tract - General principles of treatment]

OBJECTIVES

The management of upper aerodigestive tract cancers is a complex specialty. It is essential to provide an update to establish optimal care. At the initiative of the INCa and under the auspices of the SFORL, the scientific committee, led by Professor Béatrix Barry, Dr. Gilles Dolivet, and Dr. Dominique De Raucourt, decided to develop a reference framework aimed at defining, in a scientific and consensus-based manner, the general principles of treatment for upper aerodigestive tract cancers applicable to all sub-locations.

METHODOLOGY

To develop this framework, a multidisciplinary team of practitioners was formed. A systematic analysis of the literature was conducted to produce recommendations classified by grades, in accordance with the standards of the French National Authority for Health (HAS).

RESULTS

The grading of recommendations according to HAS standards has allowed the establishment of a reference for patient care based on several criteria. In this framework, patients benefit from differentiated care based on prognostic factors they present (age, comorbidities, TNM status, HPV status, etc.), conditions of implementation, and quality criteria for indicated surgery (operability, resectability, margin quality, mutilation, salvage surgery), as well as quality criteria for radiotherapy (target volume, implementation time, etc.). The role of medical and postoperative treatments was also evaluated based on specific criteria. Finally, supportive care must be organized from the beginning and throughout the patients' care journey.

CONCLUSION

All collected data have led to the development of a comprehensive framework aimed at harmonizing practices nationally, facilitating decision-making in multidisciplinary consultation meetings, promoting equality in practices, and providing a state-of-the-art and reference practices for assessing the quality of care. This new framework is intended to be updated every 5 years to best reflect the latest advances in the field.

Perineural Invasion Is a Significant Prognostic Factor in Oral Squamous Cell Carcinoma: A Systematic Review and Meta-Analysis

(1) Objectives: This systematic review and meta-analysis aimed to summarize current evidence regarding the prognostic role of perineural invasion (PNI) in patients with oral squamous cell carcinoma (OSCC). (2) Methods: We searched Cochrane Central, ProQuest, PubMed, Scopus, Science Direct, and Web of Science, using relevant keywords to identify eligible articles. Two independent reviewers conducted two-stage screening, data extraction, and quality assessment. The risk of bias was assessed using the Newcastle-Ottawa Scale (NOS) criteria. All analyses were performed using comprehensive meta-analysis (CMA; version 3.3.070) software. (3) Results: The study included 101 published articles encompassing 26,062 patients. The pooled analyses showed that PNI was associated with significantly worse overall survival (OS; HR = 1.45, 95% CI: 1.32-1.58; p < 0.001), worse disease-specific survival (DSS; HR = 1.87, 95% CI: 1.65-2.12; p < 0.001), and worse disease-free survival (DFS; HR = 1.87, 95% CI: 1.65-2.12; p < 0.001). Similarly, both local recurrence-free survival (LRFS) and regional recurrence-free survival (RRFS) were worse in patients with PNI (HR = 2.31, 95% CI: 1.72-3.10, p < 0.001; and HR = 2.04, 95% CI: 1.51-2.74, p < 0.001), respectively. The random-effect estimate of three studies demonstrated that the presence of PNI was associated with worse failure-free survival (FFS; HR = 2.59, 95% CI: 1.12-5.98, p < 0.001). (4) Conclusions: The current evidence suggests that PNI can be used as an independent predictor of the prognosis for patients with OSCC. The presence of PNI was associated with worse OS, DFS, DSS, FFS, and with recurrence. Asian patients and patients with extra-tumoral or peripheral PNI invasion were associated with worse prognosis.

Clinical Experience with Autofluorescence Guided Oral Squamous Cell Carcinoma Surgery

In our study, the effect of the use of autofluorescence (Visually Enhanced Lesion Scope-VELscope) on increasing the success rate of surgical treatment in oral squamous carcinoma (OSCC) was investigated. Our hypothesis was tested on a group of 122 patients suffering from OSCC, randomized into a study and a control group enrolled in our study after meeting the inclusion criteria. The preoperative checkup via VELscope, accompanied by the marking of the range of a loss of fluorescence in the study group, was performed before the surgery. We developed a unique mucosal tattoo marking technique for this purpose. The histopathological results after surgical treatment, i.e., the margin status, were then compared. In the study group, we achieved pathological free margin (pFM) in 55 patients, pathological close margin (pCM) in 6 cases, and we encountered no cases of pathological positive margin (pPM) in the mucosal layer. In comparison, the control group results revealed pPM in 7 cases, pCM in 14 cases, and pFM in 40 of all cases in the mucosal layer. This study demonstrated that preoperative autofluorescence assessment of the mucosal surroundings of OSCC increased the ability to achieve pFM resection 4.8 times in terms of lateral margins.

Patients of stage I oral cancer with pathologically low‐risk feature managed by primary tumor resection alone: Impact of depth of invasion and a nomogram analysis

Objectives

To evaluate the importance of depth of invasion (DOI) in patients with pathologically low‐risk feature stage I oral squamous cell carcinoma (OSCC) managed by primary tumor resection alone.

Methods

Patients with stage I OSCC, at pathologically low risk, underwent primary tumor resection without neck dissection were enrolled retrospectively between 2007 and 2015. Low risk was defined as the absence of positive or close margins, lymphovascular invasion, perineural invasion, worst pattern of invasion‐5, and poor differentiation in histologic grade. The primary endpoints included overall survival (OS), cancer specific survival (CSS), local recurrence free survival (LRFS), and regional recurrence free survival (RRFS). A nomogram based on the DOI was established for predicting RRFS.

Results

A total of 198 patients were enrolled in this study. DOI was the only prognosticator to achieve statistical significance in all primary endpoints according to univariate analysis. Patients with DOI <3 mm tumor showed better five‐year OS, CSS, LRFS, and RRFS than those with DOI ≥3 mm tumor. The concordance index of the nomogram model without DOI was 0.684, which could increase to 0.733 when DOI was included in the calculation.

Conclusion

Patients with pathologically low‐risk stage I OSCC correlate with a higher chance in occult neck metastasis if increasing DOI (≥3 mm) is noticed. Indeed, the chance of occult neck metastasis is significantly higher in this group (14% vs. 2%) than in those with DOI <3 mm. Elective neck dissection is advised if DOI is ≥3 mm to achieve better clinical outcomes.

Level of Evidence

4.

Prognostic impact of perineural invasion in oral cancer: a systematic review

Introduction

Numerous studies have evaluated the prognostic significance of perineural invasion (PNI) in oral cancer; however, the results are inconclusive.

Purpose

To identify the prognostic value of PNI in oral cancer through a metanalysis.

Methods

A literature review was carried out, searching the MedLine databases via Pubmed, Scielo, Lilacs, Cochrane and Websco.

Results

A total of 56 studies were included. The results indicate that PNI in oral cancer has an incidence of 28% (95% confidence interval (CI) 24-31%); 5-year survival with relative risk (RR) 0.67 (0.59-0.75); 5-year disease-free survival RR 0.71 (0.68-0.75); locoregional recurrence with RR 2.09 (1.86-2.35).

Conclusions

PNI is a negative prognostic factor in oral cancer.

Molecular and Cellular Mechanisms of Perineural Invasion in Oral Squamous Cell Carcinoma: Potential Targets for Therapeutic Intervention

Simple Summary

Squamous cell carcinoma is the most common type of oral cavity cancer. It can spread along and invade nerves in a process called perineural invasion. Perineural invasion can increase the chances of tumor recurrence and reduce survival in patients with oral cancer. Understanding how oral cancer interacts with nerves to facilitate perineural invasion is an important area of research. Targeting key events that contribute to perineural invasion in oral cavity cancer may reduce tumor recurrence and improve survival. In this review, we describe the impact of perineural invasion in oral cancer and the mechanisms that contribute to perineural invasion. Highlighting the key events of perineural invasion is important for the identification and testing of novel therapies for oral cancer with perineural invasion.

Abstract

The most common oral cavity cancer is squamous cell carcinoma (SCC), of which perineural invasion (PNI) is a significant prognostic factor associated with decreased survival and an increased rate of locoregional recurrence. In the classical theory of PNI, cancer was believed to invade nerves directly through the path of least resistance in the perineural space; however, more recent evidence suggests that PNI requires reciprocal signaling interactions between tumor cells and nerve components, particularly Schwann cells. Specifically, head and neck SCC can express neurotrophins and neurotrophin receptors that may contribute to cancer migration towards nerves, PNI, and neuritogenesis towards cancer. Through reciprocal signaling, recent studies also suggest that Schwann cells may play an important role in promoting PNI by migrating toward cancer cells, intercalating, and dispersing cancer, and facilitating cancer migration toward nerves. The interactions of neurotrophins with their high affinity receptors is a new area of interest in the development of pharmaceutical therapies for many types of cancer. In this comprehensive review, we discuss diagnosis and treatment of oral cavity SCC, how PNI affects locoregional recurrence and survival, and the impact of adjuvant therapies on tumors with PNI. We also describe the molecular and cellular mechanisms associated with PNI, including the expression of neurotrophins and their receptors, and highlight potential targets for therapeutic intervention for PNI in oral SCC.

Neck failure following pathologically node-negative neck dissection (pN0) in oral squamous cell carcinoma: a systematic review and meta-analysis

Due to the risk of occult cervical metastasis, elective neck dissection (END) is recommended in the management of patients with early oral cavity squamous cell carcinoma (OSCC) and a clinically node-negative (cN0) neck. This paper presents a systematic review and meta-analysis of studies that recorded isolated regional recurrence (RR) in the pathologically node-negative neck dissection (pN0) neck following END in order to quantify the failure rate. Pubmed and Ovid databases were systematically searched for relevant articles published between January 2009 and January 2019. Studies reporting RR following END in patients with OSCC who had no pathological evidence of lymph node metastasis were eligible for inclusion in this meta-analysis. In addition, a selection of large head and neck units were invited to submit unpublished data. Search criteria produced a list of 5448 papers, of which 18 studies met the inclusion criteria. Three institutions contributed unpublished data. This included a total of 4824 patients with median follow-up of 34 months (2.8 years). Eight datasets included patients staged T1-T4 with RR 17.3% (469/2711), 13 datasets included patients staged T1-T2 with RR 7.5% (158/2113). Overall across all 21 studies, isolated neck recurrence was identified in 627 cases giving a RR of 13.0% (627/4824) on meta-analysis. Understanding the therapeutic effectiveness of END provides context for evaluation of clinical management of the cN0 in these patients. A pathologically negative neck does not guarantee against future recurrence.

The Indications for Elective Neck Dissection in T1N0M0 Oral Cavity Squamous Cell Carcinoma

PURPOSE

The management of the clinically node-negative neck in T1 oral cavity squamous cell carcinoma (SCC) is controversial. The purpose of this study was to investigate tumor characteristics of surgically managed patients with T1N0 oral cavity SCC and determine the possible benefits of elective neck dissection (END).

MATERIALS AND METHODS

A retrospective cohort study was conducted assessing outcomes for patients with stage I oral SCC at Waikato Hospital, New Zealand, between 2008 and 2018. Clinical staging was based on the American Joint Committee on Cancer Cancer Staging Manual, 8^th Edition. Patients with T1N0 SCC either had an END or had the neck observed. These data were used to determine the rate of occult nodal disease, recurrence rate, and survival. Data collected included patient demographics, location, tumor characteristics including differentiation, depth of invasion (DOI), perineural invasion (PNI), lymphovascular invasion, closest histologic margin, management of the neck, the number of pathologic lymph nodes, adjuvant treatment, recurrence, and survival.

RESULTS

A total of 70 patients were included in the study (40 male, 30 female; age range 30 to 91; mean age 65 years). Twenty-seven (38.6%) patients underwent END, whereas 43 patients (61.4%) were observed. Occult nodal metastases were diagnosed in 6 of 27 (22.2%) patients who underwent END. Regional relapse occurred in 7 of 43 (16.3%) patients who were observed. Risk factors for nodal disease included increasing DOI ≥ 3 mm (P = .049), poor tumor differentiation (P = .003), and presence of PNI (P = .002). Negative prognostic factors for overall survival included male gender (P = .02, hr = 3.55, CI for HR (1.18, 10.65)), presence of PNI (P = .001, hr = 4.52, CI for HR (1.77, 11.57)), and locoregional recurrence (P < .005, hr = 6.55, CI for HR (2.69, 15.98)). Six of the 7 tumors that relapsed in the neck after observation had a primary tumor DOI < 3 mm.

CONCLUSIONS

There is little data published for management outcomes of the node-negative neck in stage I oral squamous cell carcinoma. Given salvage neck dissection carries a poorer prognosis, END should be recommended for all T1N0 oral SCC with DOI ≥ 3 mm. In cases of DOI < 3 mm undergoing primary ablation only, a staging neck dissection as a second procedure should be considered in the presence of poor tumor differentiation or PNI on final histology.

Small and Thin Oral Squamous Cell Carcinomas may Exhibit Adverse Pathologic Prognostic Features

We set out to record the frequency of recognised adverse pathologic features in early oral squamous cell carcinoma (OSCC) and correlate with neck disease, in particular in small and thin carcinomas, a group that might be assumed to behave less aggressively. We also examined the possibility of a biopsy site interfering with assessment of WPOI5 in small tumors. We reviewed all OSCCs ≤ 20 mm size and ≤ 10 mm depth reported at our institution over a 5-year period. Tumor maximum dimension, depth, perineural invasion (PNI), lymphovascular invasion (LVI), worst pattern of invasion (WPOI), and nodal status were recorded. Out of 95 cases, there were 44 (46.3%) small and 78 (82.1%) thin OSCCs. Depth and WPOI were significant factors in predicting nodal disease. There were 41 (43.2%) OSCC that were small and thin, of which 9.8% had PNI, none had LVI, and 61% had WPOI 4 or 5. Their rate of PNI and of nodal disease was similar to the other early OSCC. Assessment of WPOI5 at a biopsy site was only a problem in 2/38 cases. In early OSCC, depth and WPOI are important factors in predicting nodal disease. The very earliest OSCC (small and thin) have a similar rate of PNI and of nodal disease to other early OSCC, suggesting that while there may be a tendency to de-escalate treatment, these small tumours should be managed in the same way as for all early OSCC. In addition, the presence of scarring due to a biopsy in very small carcinomas rarely affects assessment of WPOI5.

Multifocal perineural invasion is a better prognosticator than depth of invasion in oral squamous cell carcinoma

OBJECTIVES

Prognostic significance of perineural invasion (PNI) in oral squamous cell carcinoma (OSCC) characterized as unifocal and multifocal was compared to depth of invasion (DOI) and extranodal extension (ENE).

MATERIALS AND METHODS

Univariable and multivariable analyses of 861 consecutive patients with OSCC undergoing treatment between 1995 and 2018 were performed, with local failure (LF) and disease-specific mortality (DSS) as the primary endpoints.

RESULTS

After adjusting for other adverse histopathological factors and adjuvant therapy, multifocal PNI was associated with a greater risk of LF (P = .01) and DSS (P = 0.02) compared to DOI. The effect of multifocal PNI was comparable to the effect of nodal metastases without ENE (P = 0.02). LF and DSS were not improved by the administration of adjuvant radiotherapy within unifocal or multifocal PNI groups.

CONCLUSION

Multifocal PNI is associated with a greater risk of death in OSCC than DOI. Its effect is comparable to that of nodal metastases (without ENE).

Early oral cavity cancer: The prognostic factors and impact of adjuvant radiation on survival

BACKGROUND

Early oral cavity cancer has good prognosis but recurrence in them is still not uncommon. There is no general consensus on the prognostic factors and adjuvant therapy that would have a significant impact on survival.

METHODS

A retrospective analysis of early oral cavity cancer patients during the time period 2009-2017. The data regarding demographics, histopathological features, and recurrence patterns were collected and analyzed.

RESULTS

Depth of invasion (DOI) was the most important prognostic factor among all the factors analyzed. Further analysis showed that addition of adjuvant radiotherapy for patients with DOI >5 mm did not show survival benefits (P = .73). Another subset analysis of patients with DOI >10 mm also did not show any survival advantage with adjuvant therapy P = .24.

CONCLUSION

There is no benefit of adding adjuvant RT in patients with DOI > 5 mm or in patients who were upstaged to T3 based only on DOI.

Impact of postoperative radiation therapy for deeply invasive oral cavity cancer upstaged to stage III

BACKGROUND

This article is about the eighth edition staging guidelines for upstaged patients with oral cavity squamous cell carcinoma (OCSCC) with >10 mm depth to pT3. This upstages some patients from stage I-II to stage III, a point at which patients are traditionally considered for postoperative radiation therapy (PORT). The role of PORT in patients upstaged for >10 mm depth is unknown.

METHODS

We identified patients with surgically resected stage I-II OCSCC with >10 mm depth who were upstaged to stage III. We used Cox proportional hazard modeling to compare patients who received PORT to those who did not (median follow-up 38.6 months).

RESULTS

We observed that 3.6% of patients with OCSCC were upstaged to stage III for depth >10 mm including 823 eligible patients. On adjusted analyses, PORT was associated with improved overall survival in patients upstaged to stage III (adjusted hazard ratio [aHR] 0.47, 95% confidence interval [CI] 0.30-0.73).

CONCLUSION

PORT is associated with improved survival for patients with OCSCC upstaged to stage III for >10 mm depth.

Effect of adjuvant radiotherapy on the local recurrence of oral squamous cell carcinoma with perineural invasion: A systematic review

Objectives of the Review

The decision whether to include postoperative radiotherapy on patients with oral squamous cell carcinoma depends on the risk of local recurrence. The objectives of this study were to systematically review literature on whether perineural invasion in oral squamous cell carcinoma patients is associated with higher local recurrence rates and whether local recurrence is influenced by the administration of postoperative radiotherapy in patients presenting with perineural invasion.

Type of Review

Systematic review.

Search Strategy

Embase, PubMed, Web Of Science.

Evaluation Method

The databases above were searched for studies that analysed: the treatment of oral squamous cell carcinoma patients with perineural invasion, local recurrence and postoperative radiotherapy. The data of seven studies were analysed qualitatively.

Results

The overall quality of the studies was moderate to low. There was no evidence of the effect of postoperative radiotherapy on local recurrence rates in patients presenting with perineural invasion. Some evidence suggests that local recurrence rates may increase in cases of multifocal perineural invasion, especially if nerves >1 mm are involved but these data should be interpreted with caution due to the low‐quality evidence.

Conclusions

High‐quality evidence regarding the prognostic value of perineural invasion and the impact of postoperative radiotherapy in patients presenting with perineural invasion is lacking in the literature, making it difficult to select a postoperative strategy for early‐stage tumours.

The role of adjuvant treatment in early-stage oral cavity squamous cell carcinoma: An international collaborative study

BACKGROUND

Up to half of patients with oral cavity squamous cell carcinoma (OCSCC) have stage I to II disease. When adequate resection is attained, no further treatment is needed; however, re-resection or radiotherapy may be indicated for patients with positive or close margins. This multicenter study evaluated the outcomes and role of adjuvant treatment in patients with stage I to II OCSCC.

METHODS

Overall survival (OS), disease-specific survival, local-free survival, and disease-free survival rates were calculated with Kaplan-Meier analysis.

RESULTS

Of 1257 patients with T1-2N0M0 disease, 33 (2.6%) had positive margins, and 205 (16.3%) had close margins. The 5-year OS rate was 80% for patients with clear margins, 52% for patients with close margins, and 63% for patients with positive margins (P < .0001). In a multivariate analysis, age, depth of invasion, and margins were independent predictors of outcome. Close margins were associated with a >2-fold increase in the risk of recurrence (P < .0001). The multivariate analysis revealed that adjuvant treatment significantly improved the outcomes of patients with close/positive margins (P = .002 to .03).

CONCLUSIONS

Patients with stage I to II OCSCC and positive/close margins have poor long-term outcomes. For this population, adjuvant treatment may be associated with improved survival. Cancer 2018;124:2948-55. © 2018 American Cancer Society.

AJCC 8th Edition oral cavity squamous cell carcinoma staging - Is it an improvement on the AJCC 7th Edition?

OBJECTIVES

To explore the prognostic and discriminatory ability of the AJCC 8th Edition Oral Cavity cancer staging in a non-North American population, and compare it to the previously used AJCC 7th Edition.

MATERIALS AND METHODS

Retrospective chart review was performed at a tertiary referral Otolaryngology, Head Neck and Skull Base Department in Australia, from June 2002 to June 2017. Oral cavity squamous cell carcinoma cases were staged according to AJCC 8th Edition, which was compared to AJCC 7th Edition staging, for disease-free survival (DFS) and overall survival (OS). DFS and OS were analysed using Kaplan-Meier curves.

RESULTS

There were 118 patients treated for OSCC, with an average age of 61 years, 63% were male. Overall survival grouped by stage demonstrated statistically significant discrimination between cancer stages using both the AJCC 7th and AJCC 8th Editions. AJCC 7th Edition did not discriminate between stages for DFS. Conversely, AJCC 8th Edition did statistically significantly discriminate for DFS (p = 0.0002). The DFS for both Stage 4a and 4b was significantly worse than cases in Stage 1. AJCC 8th Edition T stage was statistically significantly related to DFS (p = 0.0199), while the AJCC 7th Edition T stage was not.

CONCLUSION

The AJCC Cancer Staging Manual 8th Edition includes both the depth of primary tumour invasion and extracapsular extension of lymph node metastases. The AJCC 8th Edition OSCC staging system showed improved disease-free survival discrimination between overall stages and between T categories, while AJCC 7th Edition did not.

Adverse pathologic features in early oral squamous cell carcinoma and the role of postoperative radiotherapy-a review

The use of postoperative radiotherapy (PORT) in early stage oral cancer with adverse pathologic features (APFs) is controversial. Prognostically relevant APFs reviewed were perineural invasion, lymphovascular invasion, depth of invasion, worst pattern of invasion, and margin status. The current literature remains divided with regard to the benefit of treatment escalation in these patients; although these patients are at high risk for recurrence, the morbidity of PORT needs to be balanced against the likely benefit in disease control. A wide heterogeneity in the literature exists, likely as a result of differences in treatment protocols. We performed a literature review of the role of PORT in early-stage oral cancer with APFs. Based on the current evidence, the decision to administer adjuvant therapy needs to be made on an individual basis; patients with >1 APF are likely to benefit from PORT, and the use of risk-scoring systems may help in decision making.