Biomarker and Pathologic Predictors of Cutaneous Squamous Cell Carcinoma Aggressiveness

Low-Level Expression of p-S6 Is Associated with Nodal Metastasis in Patients with Head and Neck Cutaneous Squamous Cell Carcinoma

Cutaneous squamous cell carcinoma (cSCC) is the second most common form of skin cancer. The incidence of metastasis for cSCC is estimated to be around 1.2-5%. Ribosomal protein S6 (p-S6) and the p21 protein (p21) are two proteins that play central roles in other cancers. These proteins may be equally important in cSCC, and together, these could constitute a good candidate for metastasis risk assessment of these patients. We investigate the relationship of p-S6 and p21 expression with the impact on the prognosis of head and neck cSCC (cSCCHN). p-S6 and p21 expression was analyzed by immunohistochemistry on paraffin-embedded tissue samples from 116 patients with cSCCHN and associations sought with clinical characteristics. Kaplan-Meier estimators and Cox proportional hazard regression models were also used. The expression of p-S6 was significantly inversely associated with tumor thickness, tumor size, desmoplastic growth, pathological stage, perineural invasion and tumor buds. p21 expression was significantly inversely correlated with >6 mm tumor thickness, desmoplastic growth, and perineural invasion. p-S6-negative expression significantly predicted an increased risk of nodal metastasis (HR = 2.63, 95% CI 1.51-4.54; p < 0.001). p21 expression was not found to be a significant risk factor for nodal metastasis. These findings demonstrate that p-S6-negative expression is an independent predictor of nodal metastasis. The immunohistochemical expression of p-S6 might aid in better risk stratification and management of patients with cSCCHN.

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.

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.

Prognostic factors of head and neck cutaneous squamous cell carcinoma: a systematic review

BACKGROUND

Head and neck cutaneous squamous cell carcinoma (HNCSCC) is a non-melanoma skin cancer that is mostly caused by solar ultraviolet radiation exposure. While it usually has an excellent prognosis, a subset of patients (5%) develops nodal metastasis and has poor outcomes. The aim of this study was to systematically review the literature and evaluate the prognostic factors of HNCSCC in order to better understand which patients are the most likely to develop metastatic disease.

METHODS

A comprehensive literature search was performed on PubMed and EMBASE to identify the studies that evaluated the prognostic factors of HNCSCC. Prognostic factors were deemed significant if they had a reported p-value of < 0.05. Proportions of studies that reported a given factor to be statistically significant were calculated for each prognostic factor.

RESULTS

The search yielded a total of 958 citations. Forty studies, involving a total of 8535 patients, were included in the final analysis. The pre-operative/clinical prognostic factors with the highest proportion of significance were state of immunosuppression (73.3%) and age (53.3%); while post-operative/pathological prognostic factors of importance were number of lymph nodes involved with carcinoma (70.0%), margins involved with carcinoma (66.7%), and tumor depth (50.0%).

CONCLUSION

This systematic review is aimed to aid physicians in assessing the prognosis of HNCSCC and identifying the subsets of patients that are most susceptible to metastasis. It also suggests that immunosuppressed patients with a high-risk feature on biopsy, such as invasion beyond subcutaneous fat, could possibly benefit from a sentinel lymph node biopsy.

Marjolin's Ulcer: Mesh-Related Vaginal Cutaneous Fistula With Superimposed Osteomyelitis and Neoplastic Transformation

Marjolin's ulcer is a rare, often aggressive squamous cell malignancy identified in previously injured areas or those affected by chronic inflammation. It often develops in deep wounds that are slow to heal or allowed to heal by secondary intention. Few reports and small case series about Marjolin's ulcer have been published. We present a unique case with well-differentiated keratinized squamous cell carcinoma arising from a mesh-related vaginocutaneous fistula with superimposed osteomyelitis. The risk of cancerous transformation leading to Marjolin's ulcer in non-healing traumatic wounds is 8.1% and 2.6% in a fistula associated with purulent-inflammatory bone diseases. Approximately 1.7% of chronic cutaneous ulcers undergo neoplastic transformation, with a disposition to squamous cell carcinoma. Women experiencing mesh complications may require multiple procedures to address these issues and, therefore, should have them addressed in a timely manner to allow for the best patient outcome. Treatment optimization on a whole should incorporate the goals outlined by the American Urogynecologic Society and the International Urogynecological Association. These include the use of relevant evidence to help guide the management of mesh complications as well as identifying the gaps in currently available evidence, developing a treatment algorithm to be used for shared decision making, and identifying provider and healthcare facility characteristics that may optimize treatment outcomes specific to mesh complications.

The Correlation Between Immunohistochemistry Findings and Metastasis in Squamous Cell Carcinoma: A Review

BACKGROUND

Cutaneous squamous cell carcinoma (SCC) is the second most common type of skin cancer. Only 2% to 5% of SCCs metastasize; however, those do carry a poor prognosis. Immunohistochemistry (IHC) is widely used by pathologists to characterize skin cancers and provide clinically useful information.

OBJECTIVE

To evaluate the potential prognostic associations between IHC findings and metastasis in SCC.

METHODS

Searches were conducted in MEDLINE via PubMed for articles published between 1999 and 2019. Search criteria included key words "immunohistochemistry" and "cutaneous squamous cell carcinoma." Six hundred and fifty-three articles were returned and screened, which ultimately left 31 for inclusion in our manuscript.

RESULTS

Thirty-one articles analyzed in this review included a discussion of the expression of a particular IHC marker and the associated risk of metastasis and/or clinical utility of IHC markers in SCC, especially metastatic SCC. Markers that had several or more studies supporting clinical utility were E-cadherin, podoplanin, CD8+ T cells, PD-L1, epidermal growth factor receptor, and Cyclin D1.

CONCLUSION

Immunohistochemistry profiling of SCC may be useful in select cases when providing a prognosis remains challenging and in identification of potential therapeutic targets for high-risk or metastatic tumors.

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.

Differential Molecular Expression Patterns Associated with Metastasis in Cutaneous Squamous Cell Carcinoma: A Systematic Review and Meta-Analysis

The majority of cutaneous squamous cell carcinomas are treated by surgical removal; however, approximately 4% of tumors will metastasize. Molecular expression testing may improve accuracy in estimating the prognosis and defining the mechanisms important in the disease progression, which may impact response to therapy. Using PubMed (MEDLINE) and EMBASE, a systematic review was performed to evaluate studies published from January 2005 to August 2019 reporting tumor protein or RNA expression along with either outcomes (metastasis or death) or a comparison of primary with metastatic tumor samples. Inclusion criteria were met by 45 studies containing 81 comparisons of 44 distinct proteins and 25 microRNAs. On meta-analysis of studies analyzing primary tumor samples in terms of later outcomes, high primary tumor expression of PD-L1 (OR = 2.34, 95% confidence interval = 1.09-5.02, P = 0.030), EGFR (OR = 2.57, 95% confidence interval = 1.24-5.33, P = 0.011), and podoplanin (OR = 2.33, 95% confidence interval = 1.00-5.41, P = 0.049) conferred increased odds for metastasis. In comparison, metastatic tissue was more likely to have a high expression of PD-L1 than primary tissue (OR = 3.13, 95% confidence interval = 1.00-9.75, P = 0.049). Further studies are needed to confirm whether testing for PD-L1, EGFR, and podoplanin expression aids in cutaneous squamous cell carcinomas prognostic estimation of metastasis or death or predicts response to therapy.

The Roles of lncRNA in Cutaneous Squamous Cell Carcinoma

Cutaneous squamous cell carcinoma derives from keratinocytes and is the second most common cause of non-melanoma skin cancer. Cutaneous squamous cell carcinoma (cSCC) develops rapidly and is also the leading cause of death in non-melanoma cancers. Lymph node metastasis occurs in 5% of cSCC patients, and some patients may even metastasize to the viscera. Patients with regional lymphatic metastasis or distant metastases have a <20% 10-year survival rate, indicating the substantial challenge in treating advanced and metastatic cSCC. Some lncRNAs have been found to be abnormally overexpressed in many tumor tissues, so that they can be considered as potential new biomarkers or targets that can be used in the diagnosis and treatment of cSCC in the future. In this review, we summarize the role of lncRNA in cutaneous squamous cell carcinoma to make a better understanding of mutations in cSCC and lay the foundation for effective target therapy of cSCC.

Regulation and Role of GLI1 in Cutaneous Squamous Cell Carcinoma Pathogenesis

Cutaneous squamous cell carcinoma (cSCC) is the second most common skin tumor in humans. Although current therapies are sufficient to clear the tumor in many cases, the overall risk of cSCC metastasis is still 5%. Alternative treatment options could help to overcome this situation. Here we focused on the role of the Hedgehog (HH) signaling pathway and its interplay with epidermal growth factor receptor (EGFR) signaling in cSCC. The analyses revealed that, despite lack of Sonic HH (SHH) expression, a subset of human cSCC can express GLI1, a marker for active HH signaling, within distinct tumor areas. In contrast, all tumors strongly express EGFR and the hair follicle stem cell marker SOX9 at the highly proliferative tumor-stroma interface, whereas central tumor regions with a more differentiated stratum spinosum cell type lack both EGFR and SOX9 expression. In vitro experiments indicate that activation of EGFR signaling in the human cSCC cell lines SCL-1, MET-1, and MET-4 leads to GLI1 inhibition via the MEK/ERK axis without affecting cellular proliferation. Of note, EGFR activation also inhibits cellular migration of SCL-1 and MET-4 cells. Because proliferation and migration of the cells is also not altered by a GLI1 knockdown, GLI1 is apparently not involved in processes of aggressiveness in established cSCC tumors. In contrast, our data rather suggest a negative correlation between Gli1 expression level and cSCC formation because skin of Ptch^+/- mice with slightly elevated Gli1 expression levels is significantly less susceptible to chemically-induced cSCC formation compared to murine wildtype skin. Although not yet formally validated, these data open the possibility that GLI1 (and thus HH signaling) may antagonize cSCC initiation and is not involved in cSCC aggressiveness, at least in a subset of cSCC.

Fibroblast growth factor receptor promotes progression of cutaneous squamous cell carcinoma

Cutaneous squamous cell carcinoma (cSCC) is a keratinocyte-derived invasive and metastatic tumor of the skin. It is the second-most commonly diagnosed form of skin cancer striking 200 000 Americans annually. Further, in organ transplant patients, there is a 65- to 100-fold increased incidence of cSCC compared to the general population. Excision of cSCC of the head and neck results in significant facial disfigurement. Therefore, increased understanding of the mechanisms involved in the pathogeneses of cSCC could identify means to prevent, inhibit, and reverse this process. In our previous studies, inhibition of fibroblast growth factor receptor (FGFR) significantly decreased ultraviolet B-induced epidermal hyperplasia and hyperproliferation in SKH-1 mice, suggesting an important role for FGFR signaling in skin cancer development. However, the role of FGFR signaling in the progression of cSCC is not yet elucidated. Analysis of the expression of FGFR in cSCC cells and normal epidermal keratinocytes revealed protein overexpression and increased FGFR2 activation in cSCC cells compared to normal keratinocytes. Further, tumor cell-specific overexpression of FGFR2 was detected in human cSCCs, whereas the expression of FGFR2 was low in premalignant lesions and normal skin. Pretreatment with the pan-FGFR inhibitor; AZD4547 significantly decreased cSCC cell-cycle traverse, proliferation, migration, and motility. Interestingly, AZD4547 also significantly downregulated mammalian target of rapamycin complex 1 and AKT activation in cSCC cells, suggesting an important role of these signaling pathways in FGFR-mediated effects. To further bolster the in vitro studies, NOD.Cg-Prkdcscid Il2rgtm1Wjl/SzJ mice with SCC12A tumor xenografts treated with AZD4547 (15 mg/kg/bw, twice weekly oral gavage) exhibited significantly decreased tumor volume compared to the vehicle-only treatment group. The current studies provide mechanistic evidence for the role of FGFR and selectively FGFR2 in the early progression of cSCC and identifies FGFR as a putative therapeutic target in the treatment of skin cancer.

Downregulation of estrogen-related receptor alpha inhibits human cutaneous squamous cell carcinoma cell proliferation and migration by regulating EMT via fibronectin and STAT3 signaling pathways

Estrogen-related receptor alpha (ERRα), one of orphan nuclear receptors, has been recently revealed as an oncogenic regulator in a variety of cancers. However, the linking gain of ERRα expression and cancer progression in cutaneous squamous cell carcinoma (cSCC) is largely unknown. Here, we showed that the mRNA and protein expression levels of ERRα were markedly higher in A431 cells compared with human keratinocyte cell line HaCaT, and targeted inhibition of ERRα by shRNA or its inverse agonist XCT790 significantly suppressed A431 cells proliferation and migration, while overexpression of ERRα promoted cell proliferation and migration. In addition, the data revealed that ERRα downregulation markedly inhibited the epithelial mesenchymal transition (EMT) of A431 cells with increasing the expression of E-cadherin and decreasing fibronectin (FN) and vimentin. Results from further experiments using Western blot suggested that ERRα suppression inhibited signal transducer and activator of transcription (STAT3) protein expression. In contrast, overexpression of ERRα promoted EMT and the activation of STAT3 pathway. Moreover, treatment with specific STAT3 inhibitor reversed EMT markers in ERRα-overexpressing A431 cells. In tumor xenografts of A431 cells, we further showed that ERRα depletion inhibited cSCC tumor growth in vivo. Taken together, these results demonstrate, for the first time, that ERRα may function as an oncoprotein in cSCC to accelerate tumor aggressiveness by promoting EMT via FN and STAT3 pathway, and it could be a novel target for cSCC therapy.

Squamous cell carcinoma in chronic osteomyelitis: a case report and review of the literature

Background

Chronic osteomyelitis is a challenging problem, and malignant transformation is a rare occurrence. We report a case of a patient with squamous cell carcinoma arising from an osteomyelitic hotbed and discuss through a literature review the etiopathogenesis, diagnosis, and treatment of this lesion.

Case presentation

A 69-year-old Italian man had sustained an exposed tibial fracture 40 years ago during a road accident, for which he had undergone various surgical osteosynthesis treatments with multiple antibiotic therapies. He presented to our hospital because of recurrence of a fistula at the proximal third of the anterior region of the tibia. For 2 months, we treated the lesion with antibiotics, and local medication with curettage. We saw no evidence of lesion improvement, and we advised the patient to undergo a knee amputation, which he refused. The alternative we chose was a surgical toilet of the osteomyelitic hotbed and used bioglass as a bone substitute. After 2 months of follow-up, we noticed a fulminating, budding formation in the area of the surgical wound that turned out to be a squamous cell carcinoma on biopsy. The patient again refused the amputation and underwent a wide-margin surgical debridement. After 2 months, the carcinoma recurred, and an above-the-knee amputation was performed.

Conclusions

Our experience with this case indicates that amputation is the most appropriate treatment for squamous carcinoma occurring in patients with chronic osteomyelitis. To avoid risks of lymphonodular and organ metastasization, this radical surgical procedure should not be delayed. Early diagnosis and timely therapy can prevent amputation only in selected cases. Surgeons who treat osteomyelitis and chronic wounds should be aware of the risk of tumor degeneration. Squamous cell carcinoma associated with chronic osteomyelitis has a low-grade malignancy, but implications of lymphonodular involvement and organ metastasis should not be excluded.