High-Risk Non-Melanoma Skin Cancers: Biological and Therapeutic Advances

Nonmelanoma skin cancers (NMSCs) are the most common cancers, with high-risk NMSCs sharing features such as poor histologic differentiation, invasion into deeper layers, and anatomic location. NMSC includes basal cell carcinoma, cutaneous squamous cell carcinoma, and Merkel cell carcinoma. Herein, the authors describe advances in understanding the genetic mechanisms of malignant transformation and the composition of tumor microenvironment for these cancers. They summarize recent therapeutic advances, including targeted therapy and immunotherapy for NMSCs. Effective skin protection against ultraviolet radiation-induced carcinogenesis remains an urgent unmet need for NMSC prevention. The authors highlight immune-based interventions as novel strategies to address this need.

Lymphatic drainage patterns of malignant skin tumors in the head and neck region: a single-center retrospective study

BACKGROUND

This study aimed to clarify the relationship between primary site and lymphatic drainage pattern for malignant skin tumors in the head and neck region. Malignant melanoma and squamous cell carcinoma in the head and neck region are known to have poor prognosis because of lymph node metastasis. Nevertheless, numerous aspects of lymphatic drainage patterns remain elusive.

METHODS

We statistically analyzed data of 47 patients with malignant skin tumors in the head and neck region. Information was collected on the patients' clinical characteristics, primary tumor site, and lymphatic drainage patterns.

RESULTS

The parotid lymph nodes drained the greatest amount of lymph from skin tumors of the head and neck. Important lymphatic drainage pathways were the superficial cervical nodes for primary tumors in the buccal/nasal region, level IA and level IB nodes for primary tumors in the lip region, the occipital nodes, posterior auricular nodes, and level VA nodes in the parietal/occipital region, and the preauricular nodes in the auricular region.

CONCLUSION

These findings have considerable significance in terms of understanding lymphatic drainage patterns for malignant skin tumors in the head and neck and may be useful for clinical decision-making and when planning treatment. Further research and clinical applications are expected to contribute to an improved prognosis in patients with cutaneous head and neck malignancies.

Sentinel lymph node biopsy versus observation in high risk cutaneous squamous cell carcinoma of head and neck: a propensity score matching analysis

Sentinel lymph node biopsy (SLNB) has gained considerable attention in the management of head and neck cutaneous squamous cell carcinoma (HNcSCC). The aim of this study was to compare the oncologic outcomes between observation and SLNB in cN0 high-risk HNcSCC patients. We retrospectively enrolled patients from the SEER database and evaluated the impact of observation versus SLNB on disease-specific survival (DSS) and overall survival (OS) using a Propensity Score Matching (PSM) analysis. A total of 9804 patients were included, with 1169 cases treated by SLNB. Successful retrieval of the sentinel lymph node was achieved in 1130 procedures. After PSM and subsequent multivariate analysis, SLNB was found to be an independent predictor for improved DSS, with a hazard ratio of 0.70 (95% confidence interval: 0.56-0.86). In patients presenting with two or three high-risk factors, SLNB was associated with better DSS (p = 0.021 and p = 0.044), but similar OS (p = 0.506 and p = 0.801) when compared to observation. However, in patients exhibiting four high-risk factors, SLNB demonstrated significantly improved DSS (p = 0.040) and OS (p = 0.028) compared to observation. Our findings suggest that SLNB is a highly feasible technique in HNcSCC and provides significant survival benefits. It is strongly recommended in patients with two or more high-risk factors, as it can help guide treatment decisions and improve patient outcomes.

Prognostic and predictive biomarkers in head and neck cancer: something old, something new, something borrowed, something blue and a sixpence in your shoe

A biomarker is a measurable indicator of biological or pathological processes or the response to an exposure or intervention and is used to guide management decisions. In head and neck pathology, biomarkers are assessed by histological criteria and immunohistochemical and molecular studies. Surgical resection remains the mainstay of management of many head and neck malignancies. Adjuvant radiotherapy and/or systemic therapy may be administered depending on the presence of adverse prognostic factors identified on histopathological or immunohistochemical examination. In this review, we outline the clinically relevant prognostic and predictive factors in head and neck malignancies including conventionally recognised factors such as tumour size, depth of invasion, lymphovascular and perineural invasion and margin status as well as novel evolving factors such as recurrent genetic rearrangements and assessment of immune checkpoints. Practical issues are discussed to assist with recognising and reporting of these factors. A summary of useful tools such as structured pathology report formats is also included to assist with comprehensive reporting of all clinically relevant parameters, minimise risk and improve workflow efficiencies.

Lymph Node Metastases from Non-Melanoma Skin Cancer of the Head and Neck

Non-melanoma skin cancer (NMSC) represents the most common malignancy in the world, comprising exceedingly common lesions such as basal cell carcinoma (BCC) and cutaneous squamous cell carcinoma (cSCC) and rare lesions such as Merkel cell carcinoma. Risk factors are widely recognized and include ultraviolet (UV) light exposure, radiation exposure, immunosuppression, and many others. As a whole, survival and functional outcomes are favorable, but each histopathological subtype of NMSC behaves differently. Treatment regimens for the primary site usually include wide surgical excision and neck dissection in cases of clinically involved metastatic lymph nodes. The elective management of draining nodal basins, however, is a contested topic. Nearly all subtypes, excluding BCC, have a significant risk of lymphatic metastases, and have been studied with regard to sentinel lymph node biopsy (SLNB) and elective neck dissection. To date, no studies have definitively established a true single standard of care, as exists for melanoma, for any of the NMSCs. As a result, the authors have sought to summarize the current literature and identify indications and management options for the management of the cervical lymphatics for each major subtype of NMSC. Further research remains critically necessary in order to develop complete treatment algorithms.

Comparing Genomic Landscapes of Oral and Cutaneous Squamous Cell Carcinoma of the Head and Neck: Quest for Novel Diagnostic Markers

Squamous cell carcinoma is the most common head and neck malignancy arising from the oral mucosa and the skin. The histologic and immunohistochemical features of oral squamous cell carcinoma (OSCC) and head and neck cutaneous squamous cell carcinoma (HNcSCC) are similar, making it difficult to identify the primary site in cases of metastases. With the advent of immunotherapy, reliable distinction of OSCC and HNcSCC at metastatic sites has important treatment and prognostic implications. Here, we investigate and compare the genomic landscape of OSCC and HNcSCC to identify diagnostically useful biomarkers. Whole-genome sequencing data from 57 OSCC and 41 HNcSCC patients were obtained for tumor and matched normal samples. Tumor mutation burden (TMB), Catalogue of Somatic Mutations in Cancer (COSMIC) mutational signatures, frequent chromosomal alterations, somatic single nucleotide, and copy number variations were analyzed. The median TMB of 3.75 in primary OSCC was significantly lower (P < .001) than that of 147.51 mutations/Mb in primary HNcSCC. The COSMIC mutation signatures were significantly different (P < .001) between OSCC and HNcSCC. OSCC showed COSMIC single-base substitution (SBS) mutation signature 1 and AID/APOBEC activity-associated signature 2 and/or 13. All except 1 HNcSCC from hair-bearing scalp showed UV damage-associated COSMIC SBS mutation signature 7. Both OSCC and HNcSCC demonstrated a predominance of tumor suppressor gene mutations, predominantly TP53. The most frequently mutated oncogenes were PIK3CA and MUC4 in OSCC and HNcSCC, respectively. The metastases of OSCC and HNcSCC demonstrated TMB and COSMIC SBS mutation signatures similar to their primary counterparts. The combination of high TMB and UV signature in a metastatic keratinizing squamous cell carcinoma suggests HNcSCC as the primary site and may also facilitate decisions regarding immunotherapy. HNcSCC and OSCC show distinct genomic profiles despite histologic and immunohistochemical similarities. Their genomic characteristics may underlie differences in behavior and guide treatment decisions in recurrent and metastatic settings.

Sentinel lymph node biopsy for head and neck cutaneous squamous cell carcinoma using the Brigham and Women's staging system: a cost analysis

The objective is to determine the cost-effectiveness of sentinel lymph node biopsy (SLNB) for cutaneous squamous cell carcinoma (CSCC) according to the Brigham and Women's Hospital (BWH) Tumor Staging system. A decision analysis was utilized to examine costs and outcomes associated with the use of SLNB in patients with high-risk head and neck CSCC. Decision tree outcome probabilities were obtained from published literature. Costs were derived from Medicare reimbursement rates (US$) and effectiveness was represented by quality-adjusted life-years (QALYs). The primary outcome was the incremental cost-effectiveness ratio (ICER), with a willingness-to-pay set at $100,000 per QALY gained. SLNB was found to be a cost-effective tool for patients with T3 tumors, with an ICER of $18,110.57. Withholding SLNB was the dominant strategy for both T2a and T2b lesions, with ICERs of - $2468.99 and - $16,694.00, respectively. Withholding SLNB remained the dominant strategy when examining immunosuppressed patients with T2a or T2b lesions. In patients with head and neck CSCC, those with T3 or T2b lesions with additional risk factors not accounted for in the staging system alone, may be considered for SLNB, while in other tumor stages it may be impractical. SLNB should only be offered on an individual patient basis.

High-Dimensional and Spatial Analysis Reveals Immune Landscape-Dependent Progression in Cutaneous Squamous Cell Carcinoma

PURPOSE

The tumor immune microenvironment impacts the biological behavior of the tumor, but its effect on clinical outcomes in head and neck cutaneous squamous cell carcinomas (HNcSCC) is largely unknown.

EXPERIMENTAL DESIGN

We compared the immune milieu of high-risk HNcSCC that never progressed to metastasis with those that metastasized using multiparameter imaging mass cytometry. The cohort included both immunosuppressed patients (IS) and patients with an absence of clinical immune-suppression (ACIS). Spatial analyses were used to identify cellular interactions that were associated with tumor behavior.

RESULTS

Nonprogressing primary HNcSCC were characterized by higher CD8+ and CD4+ T-cell responses, including numerically increased regulatory T cells. In contrast, primary lesions from HNcSCC patients who progressed were largely devoid of T cells with lower numbers of innate immune cells and increased expression of checkpoint receptors and in the metastatic lesions were characterized by an accumulation of B cells. Spatial analysis reveals multiple cellular interactions associated with nonprogressing primary tumors that were distinct in primary tumors of disease-progressing patients. Cellular regional analysis of the tumor microenvironment also shows squamous cell-enriched tumor regions associated with primary nonprogressing tumors.

CONCLUSIONS

Effective responses from both CD8+ and CD4+ T cells in the tumor microenvironment are essential for immune control of primary HNcSCC. Our findings indicate that the early events that shape the immune responses in primary tumors dictate progression and disease outcomes in HNcSCC.

Management of the parotid for high-risk cutaneous squamous cell carcinoma: A review from the salivary section of the American Head and Neck Society

BACKGROUND

Metastases to the parotid nodal basin in patients with high-risk cutaneous squamous cell carcinoma (HRcSCC) impact disease specific survival (DSS) and overall survival (OS).

METHODS

A writing group convened by the Salivary Section of the American Head and Neck Society (AHNS) developed contemporary, evidence-based recommendations regarding management of the parotid nodal basin in HRcSCC based on available literature, expert consultation, and collective experience. The statements and recommendations were then submitted and approved by the AHNS Salivary Committee.

RESULTS

These recommendations were developed given the wide variation of practitioners who treat HRcSCC in order to streamline management of the parotid nodal basin including indications for imaging, surgery, radiation, and systemic treatment options as well.

CONCLUSIONS

This clinical update represents contemporary optimal management of the parotid nodal basin in HRcSCC and is endorsed by the Salivary Section of the AHNS.

A Call for Evidence-Based Conservative Management of Nail Unit Malignancies

SUMMARY

Nail unit squamous cell carcinoma and melanoma are the most common malignancies of the nail apparatus. Compared to their cutaneous counterparts, they are diagnosed later and perceived as more aggressive. This may result in overzealous management, including radiographic imaging with poor sensitivity and specificity, interventional nodal staging by sentinel lymph node biopsy, amputation over digit-sparing tumor resections, and elaborate reconstructions after tumor extirpation. In this review article, the authors evaluate the evidence behind several misconceptions in nail malignancy management and provide evidence-based guidance for more conservative care.

Outcomes of Sentinel Lymph Node Biopsy for Primary Cutaneous Squamous Cell Carcinoma of the Head and Neck

BACKGROUND

Limited data exist on sentinel lymph node biopsy (SLNB) for cutaneous squamous cell carcinoma (cSCC) of the head and neck.

OBJECTIVE

To review the results of SLNB for patients with cSCC of the head and neck at the authors' institution.

MATERIALS AND METHODS

A retrospective review was completed for patients who underwent SLNB for cSCC of the head and neck over 19 years. Patient demographics, immune status, tumor stage, total patients with positive SLNB, local recurrence, nodal recurrence, in-transit metastasis, and disease-specific death were recorded.

RESULTS

Sixty patients underwent lymphoscintigraphy, and an SLN was identified in 58 patients. The mean follow-up was 3.2 years (range, 15 days-16 years). Four patients (6.9%) had a positive SLNB. All were Brigham and Women's Hospital (BWH) stage T2b tumors. Three of these patients were immunosuppressed, 3 patients underwent neck dissection, and 2 patients received adjuvant radiation. None developed local or regional recurrence. Of the 53 patients with a negative SLNB, there were 4 local recurrences, 2 in-transit metastases, and no nodal recurrences.

CONCLUSION

Immunosuppressed patients with tumors BWH stage T2b or greater may be a reasonable cohort to focus future prospective studies on the utility of SLNB in cSCC of the head and neck.

Adjuvant radiotherapy may not significantly change outcomes in high-risk cutaneous squamous cell carcinomas with clear surgical margins: A systematic review and meta-analysis

BACKGROUND

The role of adjuvant radiotherapy for high-risk cutaneous squamous cell carcinomas (cSCC) after surgery with negative margins is unclear.

OBJECTIVE

To conduct a systematic review and meta-analysis examining the risk of poor outcomes for those treated with surgery vs. surgery and adjuvant radiotherapy.

METHODS

A comprehensive search of articles was executed in PubMed, Embase, and Cochrane Database. Random-effected meta-analyses were conducted.

RESULTS

Thirty-three studies comprised of 3,867 high-risk cSCC were included. There were no statistically significant differences in poor outcomes between the surgery vs. surgery and adjuvant radiotherapy groups. Estimates for local recurrence were 15.2% (95% confidence interval [CI]: 6.3%-27%) vs. 8.8% (CI: 1.6%-20.9%), regional metastases were 11.5% (CI: 7.2%-16.7%) vs. 4.4% (CI: 0%-18%), distant metastases were 2.6% (CI: 0.6%-6%) vs. 1.7% (CI: 0.2%-4.5%) and disease-specific deaths were 8.2% (CI: 1.2%-20.6%) vs. 19.7% (CI: 3.8%-43.7%) for the surgery group vs. surgery and adjuvant radiotherapy group respectively.

LIMITATIONS

Retrospective nature of most studies with a lack of sufficient patient-specific data.

CONCLUSIONS

For patients with high risk cSCC treated with margin-negative resection, there were no differences in poor outcomes between the surgery vs. surgery and adjuvant radiotherapy groups. Randomized-controlled trials are necessary to define the benefit of adjuvant radiotherapy in this setting.

New Developments in the Management of Cutaneous Squamous Cell Carcinoma

LEARNING OBJECTIVES

After studying this article, the participant should be able to: 1. List important prognostic features that affect cutaneous squamous cell carcinoma risk. 2. Summarize the changes to the AJCC Cancer Staging Manual, Eighth Edition, staging system for cutaneous squamous cell carcinoma. 3. Evaluate the draining nodal basin with appropriate imaging modalities. 4. Recommend adjuvant radiation therapy in the correct clinical setting for high-risk tumors. 5. Recognize the currently available treatments for advanced cutaneous squamous cell carcinoma.

SUMMARY

This continuing medical education article reviews the features, management, and prognosis of cutaneous squamous cell carcinoma with an emphasis on high-risk squamous cell carcinoma and data from the past 3 years. This review will discuss the primary tumor management, high-risk features of a squamous cell carcinoma, changes to the American Joint Committee on Cancer staging system, and the utility of sentinel lymph node biopsy, and critically review the evidence regarding adjuvant therapy.

Elective management of regional nodal basins in cutaneous squamous cell carcinoma of the head and neck: Controversies and contemporary perspectives

Non-melanoma skin cancer (NMSC) is among the most common cancers worldwide, with an incidence that continues to rise. Although cutaneous squamous cell carcinoma (cSCC) constitutes only approximately 20% of such cases, it represents the most common cause of NMSC mortality, owing largely to the propensity for development of regional lymph node metastases (LNM), which, when present, carry a dismal prognosis. Whilst overall rates of LNM are low, there are a number of patient and tumour factors that likely confer considerably higher risks, which has led several investigators to propose more proactive elective management of regional nodal basins in selected high-risk cases. Current international guidelines, however, do not recommend any elective treatment or sampling of regional nodal basins in the absence of clinically apparent disease. The purpose of this review is to explore in detail the fundamental issues underlying this controversy, focusing specifically on cSCC of the head and neck (cSCCHN). In particular the rationale for more a proactive elective approach to regional nodal basins, including the evidence-base underlying identification of potentially high-risk factors for development of LNM is discussed, along with oncological outcomes for those patients that do go onto suffer LNM. We also provide contemporary perspectives and evidence for approaches to electively managing regional nodal basins, and offer insight into how these may develop both in the clinical and research arenas.

Clinician perspectives on the factors influencing prognostic stratification by the American Joint Commission on Cancer Head and Neck Cutaneous Squamous Cell Carcinoma Staging

BACKGROUND

The eighth edition of the American Joint Committee on Cancer Staging Manual includes a staging system for head and neck cutaneous squamous cell carcinoma for the first time. The pN categories for head and neck cutaneous squamous cell carcinoma and mucosal squamous cell carcinoma are identical, despite the vastly different biological behavior of these diseases. This study aimed to survey head and neck cancer specialists' views regarding the clinical utility of the American Joint Committee on Cancer Staging Manual for head and neck cutaneous squamous cell carcinoma and to identify avenues for improvement.

DESIGN

An electronic survey of 19 questions relating to the prognostic utility of the staging system was designed based on the findings of a literature review. The survey was distributed internationally to specialists managing head and neck cutaneous squamous cell carcinoma.

RESULTS

Literature review identified 9 articles describing primary research relevant to the performance of the American Joint Committee on Cancer Staging Manual for head and neck cutaneous squamous cell carcinoma, which recognized a lack of homogeneity, monotonicity, and distinctiveness in the pN staging system. One hundred and five survey responses were received: 71% indicated that mucosal and head and neck cutaneous squamous cell carcinoma require different nodal staging categories; 63% indicated that immunosuppression should be included in the staging system; 70% thought that soft tissue metastases portend a worse prognosis compared with extranodal extension; 38% almost never saw pN3a tumors; and 40% felt that the N stage is a poor predictor of survival.

CONCLUSION

The views of head and neck cancer specialists across disciplines and countries align with evidence suggesting that head and neck cutaneous squamous cell carcinoma merits a staging system distinct from mucosal squamous cell carcinoma, that immunosuppression should be considered in prognostication, and that the use of extranodal extension should be modified.

Sentinel Lymph Node Biopsy in High-Risk Cutaneous Squamous Cell Carcinoma: Analysis of a Large Size Retrospective Series

BACKGROUND

One of the most important prognostic factors for mortality in cutaneous squamous cell carcinoma (cSCC) is the development of nodal metastasis. There is no consensus regarding which patient with cSCC should be offered sentinel lymph node biopsy (SLNB).

OBJECTIVE

This study aimed to establish the rate of positive SLNBs among patients with high-risk cSCCs and to identify which high-risk features are associated with a positive SLNB.

METHODS

Five-year retrospective case series in an academic tertiary care center reviewing 93 SLNBs.

RESULTS

Of the 93 SLNBs performed, 5 (5.4%) were positive. Three patients (3/5) had neck dissection and one (1/5) had radiation therapy, with no recurrence at the time of last follow-up. A tumor diameter ≥2 cm, a tumor depth >6 mm or below subcutaneous fat, perineural invasion of nerves with a diameter ≥0.1 mm, moderate or poor histological differentiation, lymphovascular invasion, and immunosuppression were associated with a positive SLNB. All tumors with a positive SLNB were classified as T2b according to the Brigham and Women's Hospital (BWH) tumor staging.

LIMITATIONS

Retrospective study and absence of a control group.

CONCLUSION

Sentinel lymph node biopsy can be considered for BWH T2b and T3 tumors. However, more randomized controlled studies are needed.

Sentinel Node Biopsy for Nonmelanoma Skin Cancer of the Head and Neck

Sentinel lymph node biopsy has the potential to impact regional control and survival for high-risk cutaneous malignancy. The outcome of sentinel lymph node biopsy is a potential guide for treatment and surveillance. The population of high-risk nonmelanoma patients that will benefit from sentinel lymph node biopsy remains to be determined. Any cutaneous malignancy with a greater than 10% risk of occult metastasis should be considered for sentinel lymph node biopsy or active surveillance. Localized cutaneous squamous cell carcinoma lesions with multiple high-risk features and nearly all patients with localized Merkel cell carcinoma should be considered for sentinel lymph node biopsy.

Facial Nerve Sacrifice During Parotidectomy for Metastatic Cutaneous Squamous Cell Carcinoma

Objective

We analyzed the incidence of facial nerve sacrifice during parotidectomy for metastatic cutaneous squamous cell carcinoma (CSCC).

Study Design

We retrospectively reviewed the charts of patients with cutaneous squamous cell carcinoma.

Setting

We used our CSCC institutional database, which includes patients treated at the University of California–Davis from 2001 to 2018.

Methods

We evaluated patients who presented with biopsy-proven head and neck CSCC who underwent parotidectomy as a part of surgical treatment. We assessed the frequency of facial nerve sacrifice required in patients with normal preoperative facial nerve function with metastatic disease to the parotid. We evaluated the association between sacrifice and high-risk tumor variables using multivariate analysis.

Results

We identified 53 patients with parotid metastasis and normal preoperative facial nerve function. Thirteen percent of patients required sacrifice of the main trunk of the facial nerve and 27% required sacrifice of a branch of the facial nerve. All patients who underwent facial nerve sacrifice had extracapsular spread (ECS). Perineural invasion (PNI) in the primary tumor (odds ratio [OR], 9.11; P = .041) and location of metastasis within the parotid body (OR, 6.6; P = .044) were independently associated with facial nerve sacrifice.

Conclusion

Patients with regionally metastatic CSCC to the parotid gland frequently require sacrifice of all or a component of the facial nerve despite normal preoperative function. The likelihood of nerve sacrifice is highest for tumors with PNI and metastatic disease within the body of the parotid.

Performance of Salamanca refinement of the T3-AJCC8 versus the Brigham and Women's Hospital and Tübingen alternative staging systems for high-risk cutaneous squamous cell carcinoma

INTRODUCTION

The Brigham and Women's Hospital and the Tübingen cutaneous squamous cell carcinoma (SCC) stratification systems propose different criteria from the American Joint Committee on Cancer, eighth edition. Our group identified prognostic subgroups within T3 stage according to the American Joint Committee on Cancer eighth edition's classification, the most common classification for high-risk cutaneous SCCs.

OBJECTIVE

To compare the performance and prognostic accuracy of these staging systems in a subset of high-risk cutaneous SCCs.

METHODS

Homogeneity, monotonicity, and McNemar tests for pairwise comparisons were assessed. Distinctiveness and relative risk of poor outcome were calculated by stage. Prognostic accuracy was compared with respect to quality (Akaike and Bayesian information criteria), concordance (Harrell C-index and Gönen and Heller concordance probability estimate), and predictive accuracy (sensitivity, specificity, negative predictive value, positive predictive value, and global accuracy).

RESULTS

The Brigham and Women's Hospital and Salamanca systems were more distinctive, homogeneous, and monotonic than the Tübingen system. The Tübingen system was the most specific, whereas the Salamanca and Brigham and Women's Hospital systems were more sensitive. Negative predictive value was high in all 3 systems, but positive predictive value and accuracy were low overall.

CONCLUSIONS

Alternative staging systems may partially overcome the heterogeneity and low prognostic accuracy of the American Joint Committee on Cancer, eighth edition and enable high-risk cutaneous SCCs to be stratified more reliably, but their prognostic accuracy is still low. Considering the accumulation of risk factors may improve high-risk cutaneous SCC risk stratification.

Outcomes and prognosticators in regionally recurrent cutaneous squamous cell carcinoma of the head and neck

INTRODUCTION

Data regarding regionally metastatic cutaneous squamous cell carcinoma of the head and neck (cSCCHN) is limited and derived almost exclusively from Australian and United States (US) institutions. We report the first United Kingdom perspective, with the aims of benchmarking survival outcomes and identifying clinically relevant prognosticators.

MATERIALS AND METHODS

Ninety-one patients with regionally recurrent cSCCHN treated with curative intent over a ten-year period (2009-2018) were studied retrospectively. Time-to-event analyses were used to estimate oncological outcomes, and log-rank statistics and Cox proportional hazards models used to examine potential prognosticators. Receiver operating characteristics were also used to analyse the influence of nodal disease burden.

RESULTS

Parotid involvement (with or without neck involvement) was most common (79.2%), and time to recurrence in those with parotid disease alone significantly shorter than for any other disease distribution (p = 0.034). Respective five-year overall, disease-specific, and disease-free survival estimates were 43.8%, 63.8%, and 36.2%. Extracapsular spread (ECS) portended reduced DFS and DSS (p = 0.012 and p = 0.005 respectively). Increasing nodal burden (≥4 involved nodes) also reduced DSS (p = 0.020), while parotid disease alone predicted more favourable DSS (p = 0.008). ECS and isolated parotid involvement remained significant on multi-variate analysis (p = 0.014 and p = 0.028 respectively).

CONCLUSIONS

Oncological outcomes were unfavourable but broadly consistent with previous reports, notionally lending support to a more proactive approach in managing the clinically node negative neck/parotid in selected high-risk cases. Our data also support distinct parotid classification and consideration of involved lymph node number in future staging systems.