Prognostic Impact of Perineural Invasion in Cutaneous Squamous Cell Carcinoma: Results of a Prospective Study of 1,399 Tumors

Sentinel lymph node biopsy versus observation in high-risk cutaneous squamous cell carcinoma in immunosuppressed and immunocompetent patients: An inverse probability of treatment weighting study

BACKGROUND

The survival benefit of sentinel lymph node biopsy (SLNB) in immunocompetent and immunosuppressed patients with high-risk cutaneous squamous cell carcinoma (cSCC) has not been established.

OBJECTIVE

To determine whether SLNB improves disease-specific survival (DSS) in high-risk cSCC. Secondary objectives were to analyse disease-free survival, nodal recurrence-free survival and overall survival (OS).

METHODS

Multicentre, retrospective, observational cohort study comparing survival outcomes in immunosuppressed and immunocompetent patients treated with SLNB or watchful waiting. Inverse probability of treatment weighting was used to adjust for possible confounding effects.

RESULTS

We studied 638 tumours in immunocompetent patients (SLNB n = 42, observation n = 596) and 173 tumours in immunosuppressed patients (SLNB n = 28, observation n = 145). Overall, SLNB was positive in 15.7% of tumours. SLNB was associated with a reduced risk of nodal recurrence (NR) (hazard ratio [HR], 0.05 [95% CI, 0.01-0.43]; p = 0.006), disease specific mortality (HR, 0.17 [95% CI, 0.04-0.72]; p = 0.016) and all-cause mortality (HR, 0.33 [95% CI, 0.15-0.71]; p = 0.004) only in immunocompetent patients.

CONCLUSIONS

SLNB was associated with improvements in NR, DSS and OS in immunocompetent but not in immunosuppressed patients with high-risk cSCC.

Grading differentiation in cutaneous squamous cell carcinoma: a review of the literature

Poor differentiation is strongly associated with poor outcomes in cutaneous squamous cell carcinoma (CSCC). In addition, the National Comprehensive Cancer Network (NCCN) guidelines designate poorly differentiated tumors as "very high risk". Despite its clear prognostic implications, there is no standardized grading system for CSCC differentiation in common use today. CSCC differentiation is graded inconsistently by both dermatopathologists and Mohs surgeons, and reliability studies have demonstrated suboptimal inter- and intra-rater reliability in both of these groups. The absence of a standardized and reliable grading system has impeded the use of differentiation in CSCC staging, despite its apparent correlation with disease outcomes. We performed a comprehensive review of the literature summarizing historical CSCC differentiation grading systems, as well as grading systems in non-cutaneous head and neck SCC as a point of reference. Relevant articles were identified by searching Embase and PubMed, as well as by reviewing reference lists for additional articles and histology textbook excerpts. CSCC grading systems that were identified and summarized include the historical Broders system, the World Health Organization system, the College of American Pathologists' system, and a system described by a 2023 Delphi consensus panel of dermatopathologists.

Perineural invasion as a predictor of local recurrence in cats with squamous cell carcinoma treated with electrochemotherapy

Introduction

Squamous cell carcinoma (SCC) is a malignant neoplasm that accounts for approximately 15-25% and 70-80% of all feline cutaneous and oral tumors, respectively. Similar to that in humans, feline SCC can be highly invasive locally; however, its metastasis rate is low. Thus, effective local treatment may be curative for most patients, and includes surgery, electrochemotherapy (ECT), cryosurgery, or a combination of these. However, this neoplasia can manifest more aggressively in some patients, leading to higher recurrence rates. In humans, perineural invasion (PNI) has been described as a relevant tumor dissemination pathway associated with high-risk SCC, resulting in higher recurrence rates, resistance to local treatments, and short survival. However, PNI and its prognostic value have not been described in feline SCC. This study aimed to evaluate the PNI in a feline population with SCC treated with ECT and correlate its presence with the occurrence of local recurrence and other clinical variables.

Methods

Twenty-four cats histopathologically diagnosed with SCC between 2013 and 2021 were retrospectively selected from the medical records of the Oncological Center Vet Cancer (São Paulo, SP, Brazil). The inclusion criteria were ECT as the sole therapy, histopathological evaluation of PNI, and absence of distant metastatic disease.

Results

The complete response rate was 96% (23/24), and PNI was identified in 33% of the cats (8/24, PNI-positive group), whereas 67% were free of this invasion (16/24, PNI-negative group). All PNI-positive cats developed local recurrence, whereas only five PNI-negative cats experienced recurrence. Local recurrence was significantly associated with PNI (p = 0.03).

Discussion

The results of this study are preliminary but promising. The data obtained are the first regarding PNI occurrence in feline SCC and pave the way for further studies, mainly to correlate the PNI with survival data and better define its prognostic value.

Perineural Invasion of Cranial Nerves in Cutaneous Squamous Cell Carcinoma: Unraveling Its Complexities, Diagnostic Challenges, and Multifaceted Treatment Approaches

Cutaneous squamous cell carcinoma is the second most common neoplasm among non-melanoma skin cancers. When associated with perineural invasion of the cranial nerves, with clinical features often observed in trigeminal and facial nerves due to their cutaneous extension, it may lead to a worse prognosis. This paper introduces a rare case of an 81-year-old male, with a history of a moderately differentiated invasive carcinoma of the left frontal region with perineural invasion on the left trigeminal cranial nerve. The case underscores the aggressive nature of the intraneural infiltration by squamous cell carcinoma and the challenges in managing such advanced malignancies.

European consensus-based interdisciplinary guideline for invasive cutaneous squamous cell carcinoma. Part 1: Diagnostics and prevention-Update 2023

Invasive cutaneous squamous cell carcinoma (cSCC) is one of the most common cancers in white populations, accounting for 20% of all cutaneous malignancies. Overall, cSCC mostly has very good prognosis after treatment, with 5-year cure rates greater than 90%. Despite the overall favourable prognosis and the proportionally rare deaths, cSCC is associated with a high total number of deaths due to its high incidence. A collaboration of multidisciplinary experts from the European Association of Dermato-Oncology (EADO), the European Dermatology Forum (EDF), the European Society for Radiotherapy and Oncology (ESTRO), the European Union of Medical Specialists (UEMS), the European Academy of Dermatology and Venereology (EADV) and the European Organization of Research and Treatment of Cancer (EORTC), was formed to update recommendations on cSCC, based on current literature and expert consensus. Part 1 of the guidelines addresses the updates on classification, epidemiology, diagnosis, risk stratification, staging and prevention in immunocompetent as well as immunosuppressed patients.

Desmoplasia in cutaneous squamous cell carcinoma with perineural invasion

This study examines the rate of desmoplasia in cutaneous squamous cell carcinoma with perineural invasion and the associated clinical outcomes.

The value of SOX10 expression in predicting perineural invasion in gastric cancer

BACKGROUND

SRY-related HMG-box 10 (SOX10) protein has a confirmed role in the regulation of neural cell proliferation and differentiation. It is now suggested that the changes in SOX10 expression may be linked to neural invasion by cancer cells. We aimed to assess the value of SOX10 expression in predicting perineural invasion in gastric cancer.

METHODS

A cross-sectional study was performed on 40 patients with gastric cancer. To assess perineural invasion, Hematoxylin & Eosin stained slides were examined. The expression of SOX10 was also examined by immunohistochemistry.

RESULTS

Our study showed higher perineural invasion in those with SOX10 positivity as compared to those without SOX10 expression (64.0% vs. 6.7%, p=0.001). No association was revealed between other baseline variables and SOX10 positivity. The expression of this marker increased the chance of neural invasion up to 17 times as indicated by the multivariable regression modeling. Multivariable regression modeling indicated that the chance of neural invasion increased up to 17 times in cases of SOX10 positivity.

CONCLUSION

Overexpression of SOX10 is closely associated with the risk of perineural invasion in gastric cancer.

Unraveling the Mysteries of Perineural Invasion in Benign and Malignant Conditions

Perineural invasion (PNI) is defined as the dissemination of neoplastic cells within the perineural space. PNI can be a strong indicator of malignancy and is linked to poor prognosis and adverse outcomes in various malignant neoplasms; nevertheless, it can also be seen in benign pathologic conditions. In this review article, we discuss various signaling pathways and neurotrophic factors implicated in the development and progression of PNI. We also describe the methodology, benefits, and limitations of different in vitro, ex vivo, and in vivo models of PNI. The spectrum of presentation for PNI can range from diffuse spread within large nerves ("named" nerves) all the way through localized spread into unnamed microscopic nerves. Therefore, the clinical significance of PNI is related to its extent rather than its mere presence or absence. In this article, we discuss the guidelines for the identification and quantification of PNI in different malignant neoplasms based on the College of American Pathologists (CAP) and World Health Organization (WHO) recommendations. We also describe benign pathologic conditions and neoplasms demonstrating PNI and potential mimics of PNI. Finally, we explore avenues for the future development of targeted therapy options via modulation of signaling pathways involved in PNI.

The pattern and spread of invasion can predict late cervical lymph node metastasis in early tongue squamous cell carcinoma

To determine the predictive indexes of late cervical lymph node metastasis in early tongue squamous cell carcinoma (TSCC). We retrospectively analyzed the cases of 25 patients with stage I/II TSCC who had undergone surgical treatment without elective neck dissection. We evaluated the relationships between clinicopathologic factors and the occurrence of late cervical lymph node metastasis. Of the 25 cases, metastasis to the cervical lymph nodes was observed in nine cases (36.0%). The clinicopathological factors associated with late cervical lymph node metastasis were the mode of invasion (MOI, p = 0.032), depth of invasion (DOI, p = 0.004), and perineural invasion (PNI, p = 0.040). A multivariate analysis revealed that only the DOI was an independent predictor of late cervical lymph node metastasis. The combination of the DOI and MOI or the PNI and MOI was significantly correlated with late cervical lymph node metastasis (p = 0.004 and p = 0.012, respectively). Our findings suggest that combinations of the MOI, DOI, and PNI could be used as an index for predicting late cervical lymph node metastasis in early TSCC.

Resection of Skin Cancer Resulting in Free Vascularized Tissue Reconstruction: Always a Therapeutic Failure?

The globally increasing incidence of cutaneous malignancies leads, in parallel, to increasing numbers of locally advanced skin cancer resulting in reconstructive surgery. Reasons for locally advanced skin cancer may be a patient's neglect or aggressive tumor growth, such as desmoplastic growth or perineural invasion. This study investigates characteristics of cutaneous malignancies requiring microsurgical reconstruction with the aim of identifying possible pitfalls and improving diagnostic and therapeutic processes. A retrospective data analysis from 2015 to 2020 was conducted. Seventeen patients (n = 17) were included. The mean age at reconstructive surgery was 68.5 (±13) years. The majority of patients (14/17, 82%) presented with recurrent skin cancer. The most common histological entity was squamous cell carcinoma (10/17, 59%). All neoplasms showed at least one of the following histopathological characteristics: desmoplastic growth (12/17, 71%), perineural invasion (6/17, 35%), or tumor thickness of at least 6 mm (9/17, 53%). The mean number of surgical resections until cancer-free resection margins (R0) were achieved was 2.4 (±0.7). The local recurrence rate and the rate of distant metastases were 36%. Identified high-risk neoplastic characteristics, such as desmoplastic growth, perineural invasion, and a tumor depth of at least 6 mm, require a more extensive surgical treatment without concerns about defect size.

Association of Patient Risk Factors, Tumor Characteristics, and Treatment Modality With Poor Outcomes in Primary Cutaneous Squamous Cell Carcinoma: A Systematic Review and Meta-analysis

Importance

Primary cutaneous squamous cell carcinoma is usually curable; however, a subset of patients develops poor outcomes, including local recurrence, nodal metastasis, distant metastasis, and disease-specific death.

Objectives

To evaluate all evidence-based reports of patient risk factors and tumor characteristics associated with poor outcomes in primary cutaneous squamous cell carcinoma and to identify treatment modalities that minimize poor outcomes.

Data Sources

PubMed, Embase, and SCOPUS databases were searched for studies of the topic in humans, published in the English language, from database inception through February 8, 2022.

Study Selection

Two authors independently screened the identified articles and included those that were original research with a sample size of 10 patients or more and that assessed risk factors and/or treatment modalities associated with poor outcomes among patients with primary cutaneous squamous cell carcinoma.

Data Extraction and Synthesis

Data extraction was performed by a single author, per international guidelines. The search terms, study objectives, and protocol methods were defined before study initiation. A total of 310 studies were included for full-text assessment. Owing to heterogeneity of the included studies, a random-effects model was used. Data analyses were performed from May 25 to September 15, 2022.

Main Outcomes and Measures

For studies of risk factors, risk ratios and incidence proportions; and for treatment studies, incidence proportions.

Results

In all, 129 studies and a total of 137 449 patients with primary cutaneous squamous cell carcinoma and 126 553 tumors were included in the meta-analysis. Several patient risk factors and tumor characteristics were associated with local recurrence, nodal metastasis, distant metastasis, disease-specific death, and all-cause death were identified. Among all factors reported by more than 1 study, the highest risks for local recurrence and disease-specific death were associated with tumor invasion beyond subcutaneous fat (risk ratio, 9.1 [95% CI, 2.8-29.2] and 10.4 [95% CI, 3.0- 36.3], respectively), and the highest risk of any metastasis was associated with perineural invasion (risk ratio, 5.0; 95% CI, 2.3-11.1). Patients who received Mohs micrographic surgery had the lowest incidence of nearly all poor outcomes; however, in some results, the 95% CIs overlapped with those of other treatment modalities.

Conclusions and Relevance

This meta-analysis identified the prognostic value of several risk factors and the effectiveness of the available treatment modalities. These findings carry important implications for the prognostication, workup, treatment, and follow-up of patients with primary cutaneous squamous cell carcinoma.

Trial Registration

PROSPERO Identifier: CRD42022311250.

Defining the Molecular Landscape of Cancer-Associated Stroma in Cutaneous Squamous Cell Carcinoma

Cutaneous squamous cell carcinoma (cSCC) is the second most common skin cancer worldwide. Cancer-associated stroma (CAS) is central to tumor development and strongly influences therapy response. Perineural infiltration (PNI) represents a major risk factor for cSCC and likely influences CAS reprogramming. However, stromal reprogramming in cSCC remains poorly characterized, and it is unknown whether and how PNI influences CAS. To address these questions, we analyzed CAS and matched normal stroma from 20 cSCC cases (11 without PNI and 9 with PNI) by laser-capture microdissection using RNA sequencing. Our analysis reveals extensive stromal reprogramming strongly driven by changes in immune cells, as validated using immunohistochemistry. Furthermore, CAS of cSCC displays markers of immune exhaustion, and multiplex spatial analysis suggests that PD-L1 expression on NK T cells contributes to T-cell exhaustion and immunosuppression. Finally, PNI is characterized by increased IL-17A. In PNI-negative cases, IL-17A derives predominantly from CD3+ cells. However, with PNI, we observe an increased contribution of fibroblasts to high IL-17A, which coincides with a significant increase in FAP+ cells. Our analysis elucidates the molecular landscape of CAS in cSCC and identifies the presence of immunosuppressive mechanisms, supporting further research into immunotherapy and anti‒IL-17A in cSCC, especially for cases with PNI.

What causes the death of patients with cutaneous squamous cell carcinoma? A prospective analysis in 1400 patients

INTRODUCTION

Cutaneous squamous cell carcinoma (cSCC) is a common tumor of elderly Caucasian patients.

METHODS

Competing multivariable risk models to analyze different types of cSCC associated death (local infiltration [LI], locoregional [LR], and distant metastases [DM]) in terms of prognostic factors.

RESULTS AND DISCUSSION

1400 patients were analyzed. In the adjusted multivariable subdistribution hazard approach for tumor volume, the best model for death of cSCC overall revealed the presence of desmoplasia (HR 4.52; p < 0.001), bone invasion (HR 10.06; p < 0.01), and immunosuppression (HR 3.19; p = 0.003) as significant factors. Death due to LI indicated desmoplasia (HR 15.39; p < 0.01) and bone invasion (HR 16.9; p < 0.001) as significant factors. For death by LM, immunosuppression with a HR of 3.27; p = 0.004 was the only significant prognostic factors as well as in death by DM with a HR of 4.54; p = 0.02.

CONCLUSIONS

The three types of death caused by cSCC can be distinguished based on risk factors with different weights. Patients with these factors should be monitored closely.

Local Tumor Infiltration and Locoregional Recurrence in Desmoplastic Cutaneous Squamous Cell Carcinoma

BACKGROUND

Perusal of the literature of cutaneous squamous cell carcinoma (SCC) reveals that the role of the desmoplastic subtype is indistinct. Data on local infiltration and recurrence are inconsistent dependent on surgical technique, histological method, and investigated collective.

OBJECTIVE

The aim of the study was to analyze local infiltration and locoregional recurrence of the desmoplastic subtype under a uniform procedure.

METHODS AND MATERIALS

Between 2005 and 2015, 320 SCCs were analyzed and histological sections of all tumors were examined. Data collection included locoregional recurrence, metastasis rate, and tumor-specific death. The median follow-up was 36.5 months.

RESULTS

The desmoplastic subtype required significant more re-excisions (70.0% vs 23.9%, p < .001), more interventions until tumor-free margins were achieved (maximal 6 vs 2; p < .001), showed more widespread tumor infiltration with larger excisional margins (median 9 mm, 2-51 mm vs median 4 mm, 1-10 mm; p < .001), and a 5-fold higher local recurrence rate (26.7% vs 5.0%, p < .001). The metastasis rate (16.6% vs 2.3%, p < .001) was increased.

CONCLUSION

The desmoplastic subtype is characterized by a widespread local infiltration associated with perineural infiltration. It seems to be a marker for decreased histological detectability with a high rate of locoregional recurrence and metastasis.

Immunotherapy for the treatment of perineural spread in cutaneous head and neck squamous cell carcinoma: Time to rethink treatment paradigms

BACKGROUND

Immune checkpoint inhibitors have shown promising antitumour activity. Application in head and neck cutaneous squamous cell carcinoma (cSCC) large nerve perineural spread (PNS) is limited.

METHODS

Retrospective review of 13 patients with PNS receiving anti-PD-1 therapy from September 2017 to May 2021 is presented. Primary endpoints were objective response (complete or partial response) and median time to progression, determined by Head and Neck Multi-Disciplinary Team (MDT) and independent radiology review of magnetic resonance imaging (MRI) and/or computed tomography/positron emission tomography (CT/PET).

RESULTS

Objective response was observed in 9/13 patients (69%), with complete response in 6 (46%) and partial response in 3 patients (23%). Median time to response was 2.1 months (IQR 1.8-2.7 months). There were 3 (23%) patients with progressive disease, with median time to progression of 3.5 months. There were no grade 3-4 treatment related adverse events.

CONCLUSIONS

This case series supports developing evidence for anti-PD-1 checkpoint inhibitor therapy for perineural spread, supporting future prospective clinical trials in this patient population.

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.

Hide-and-seek: Neurotropic squamous cell carcinoma of the periorbital region - a series of five cases and review of the literature

Squamous cell carcinoma is the second most common malignancy of the skin after basal cell carcinoma and mainly found in sun‐exposed areas such as the face. This mostly locally destructive malignancy may show invasive growth and insidious mechanisms of dissemination such as perineural invasion. Periorbital squamous cell carcinoma is associated with perineural invasion in up to 14 % of cases. Specifically in this region, the proximity to cranial nerves and therefore the associated risk of progression to the central nervous system are associated with poor prognosis. The clinically concealed character of this entity often leads to a delay in diagnosis and consequently makes complete resection and reconstruction demanding. Careful clinical evaluation often hints at perineural invasion before obtaining histology.

Aside from presenting five challenging cases, this work analyzes risk factors, clinical as well as histological features, and treatment options for periorbital squamous cell carcinoma with perineural invasion.

Hide-and-seek: Neurotropes Plattenepithelkarzinom der periorbitalen Region - eine Fallserie und Übersichtsarbeit aktueller Literatur

Das Plattenepithelkarzinom ist nach dem Basalzellkarzinom das zweithäufigste Malignom der Haut und wird vorwiegend an sonnenexponierten Stellen wie der Gesichtshaut diagnostiziert. Diese meist lokal destruktiv wachsende Malignität kann durchaus auch invasives Wachstumsverhalten, wie perineurale Ausbreitungsmechanismen, aufweisen. Das Plattenepithelkarzinom der periorbitalen Region ist in bis zu 14 % der Fälle mit perineuraler Invasion assoziiert. Vor allem in diesem Bereich birgt die anatomische Nähe zu den Hirnnerven das Risiko einer Progression Richtung zentrales Nervensystem, was mit einer schlechteren Prognose assoziiert ist. Der klinisch unauffällige Charakter dieser Entität resultiert oft in einer Verzögerung der definitiven Diagnosestellung, wodurch die vollständige Resektion und anschließende Rekonstruktion erschwert werden. Eine aufmerksame klinische Evaluierung kann bereits vor Erlangen histologischer Befunde Hinweise für ein perineurales Wachstum liefern. Neben fünf herausfordernden Fällen analysiert diese Arbeit Risikofaktoren, klinische als auch histologische Merkmale und Behandlungsoptionen des periorbitalen Plattenepithelkarzinoms mit perineuraler Invasion.

Intracranial Infiltration of a Scalp Neoplasm After Hair Dyeing 10 Years Ago

ABSTRACT

Cosmetics with unknown chemical components may cause unexpected cancers. Here, we report a rare case of hair dye-induced intracranial communicating scalp sebaceous carcinoma in a young female who dyed her hair 10 years ago. The histological origin of the intracranial communicating neoplasm was of priority for subsequent therapeutic decisions, therefore, requiring comprehensive diagnostic strategy. In conclusion, this case report emphasizes careful evaluation of the long-term risks for unlabeled cosmetics.

A Histopathologic Scoring System for Perineural Invasion Correlates With Adverse Outcomes in Patients With Cutaneous Squamous Cell Carcinoma

BACKGROUND

Perineural invasion (PNI) is a known risk factor for recurrence, metastasis, and death in cutaneous squamous cell carcinoma (cSCC). Current staging systems include PNI, but none define its extent or severity.

OBJECTIVE

To identify histopathologic features of cSCC with PNI that may be associated with adverse outcomes.

MATERIALS AND METHODS

This is a retrospective cohort study that included 45 patients with cSCC and PNI treated with surgical excision. Histopathologic slides were analyzed for 5 features of PNI: largest affected nerve diameter, number of nerves affected, depth of nerve involvement, intra- versus extratumoral PNI, and focal versus circumferential PNI.

RESULTS

The median largest affected nerve diameter was 0.13 mm, and the median number of nerve structures involved was 4. After a median follow-up time of 24 months, 6 patients developed adverse outcomes, including 2 local recurrences, 4 metastases, and 2 tumor-related deaths. Univariate logistic regression analysis revealed that nerve diameter and number of affected nerves were significantly associated with adverse outcome. A composite PNI score, calculated from 5 histopathologic features, was the strongest predictor of adverse outcome (p = .020).

CONCLUSION

Histopathologic features of PNI can be quantified with a composite PNI score that is significantly associated with adverse outcomes in cSCC.

Histopathologic upgrading of cutaneous squamous cell carcinomas during Mohs micrographic surgery: A retrospective cohort study

BACKGROUND

Initial biopsies of cutaneous squamous cell carcinomas (cSCCs) may not reveal aggressive histologic features, which would otherwise inform appropriate surgical management and patient education.

OBJECTIVE

To assess the incidence of, and risk factors for, histopathologic upgrading of cSCC during Mohs micrographic surgery (MMS).

METHODS

This was a retrospective cohort study of invasive cSCCs treated with MMS between 2017 and 2019 at 1 academic institution. An "upgrade" was defined as a lesser degree of differentiation (poor or moderate) and/or bony or perineural invasion identified during MMS that was not reported in histopathologic evaluation of the initial biopsy.

RESULTS

Of the 1558 tumors studied, 115 (7.4%) were upgraded during MMS. In multivariate logistic regression analysis, male sex, prior field treatment, location on the ear/lip, rapid growth of cSCC, and tumor diameter ≥2 cm were significant predictors of tumor upgrading. Upgraded tumors were more likely to require ≥3 MMS stages to clear, complicated closure (flap or graft), or outside (referral) repairs.

LIMITATIONS

Single-center study, retrospective, and inter-rater variability.

CONCLUSIONS

A significant proportion of cSCCs is histopathologically upgraded with more aggressive features during MMS. Routinely documented patient and tumor characteristics can predict tumor upgrading and assist clinicians in directing the management of potentially high-risk cSCC patients.

Clinicopathological Correlations in Cutaneous Squamous Cell Carcinomas

Squamous cell carcinomas (SCC) represent 20% of all nonmelanoma skin cancers, most tumors responding favorably to the conventional therapy. Incisional or excisional biopsy is essential for diagnosis and prognosis evaluation. The study included 103 cases of SCC, following the assessment of some clinical and histopathological aggressivity factors, which were digitally stored and statistically analyzed using comparison tests. The tumor grade was significantly associated with the histological variant, the maximum tumor size, the perineural and lymphovascular invasion, the depth of the invasion and the status of resection limits. The pT category was significantly associated with the location and maximum tumor size, perineural invasion, depth of invasion and status of resection limits. It was observed a significant association of tumor grade and pT category. The evaluation of the clinical and histological characteristics of SCC is an important step in obtaining relevant prognostic information and applying appropriate therapy.

Risk Factors Party Together: The Role of Perineural Invasion and Desmoplasia in Cutaneous Squamous Cell Carcinoma Prognosis

In the current issue, Haug et al. 2020 report on the prognostic impact of perineural invasion (PNI) and desmoplasia on cutaneous squamous cell carcinoma (CSCC) recurrence and metastasis. They find that PNI occurs exclusively in desmoplastic CSCC, and desmoplasia is independently associated with CSCC recurrence and metastasis after adjusting for well-established CSCC risk factors. Future studies should assess the contribution of desmoplasia in CSCC prognosis.

[Cutaneous squamous cell carcinoma]

Cutaneous squamous cell carcinoma (cSCC) is one of the most common cancers of the Caucasian population and accounts for 20% of all skin tumours. An S3 guideline of the German Guideline Program in Oncology has been available since 2019. The diagnosis is based on the clinical examination. Excision and histological confirmation is required for all clinically suspicious lesions to allow prognostic assessment and correct treatment. The therapy of first choice is complete excision with histological control of the surgical margin. In cSCC with risk factors such as tumor thickness >6 mm, sentinel lymph node biopsy may be discussed, but there is currently no clear evidence of its prognostic and therapeutic relevance. Adjuvant radiation therapy may be considered in cases of high risk of recurrence and should be tested in cases of inoperable tumors. The indication for electrochemotherapy should also be considered in the treatment of local or locoregional recurrence. The immune checkpoint inhibitor cemiplimab is approved for the treatment of inoperable or metastasized cSCC. In case of contraindications, chemotherapeutic agents, epidermal growth factor receptor (EGFR) inhibitors or palliative radiotherapy can be used. Since the evidence is low in these cases, a systemic therapy should be used preferentially within clinical studies. Follow-up care should be risk-adapted and includes a dermatological control, supplemented by ultrasound examinations in high-risk patients.