Systemic treatment of locally advanced nonmetastatic cutaneous squamous cell carcinoma: a review of the literature

[The Cutaneous Squamous Cell Carcinoma - An Update]

BACKGROUND

The cutaneous squamous cell carcinoma (CSCC) is the second most common nonmelanoma skin cancer with an increasing incidence rate. Patients presenting with high-risk lesions associated with locally advanced or metastatic CSCC face high rates of recurrence and mortality.

METHODS

Selective literature review based on PubMed and consideration of current guidelines "Aktinische Keratosen und Plattenepithelkarzinom der Haut" and "Prävention von Hautkrebs".

FINDINGS

Complete surgical excision with histopathological control of excision margins is the gold standard in the treatment of primary CSCC. Radiotherapy can be used as an alternative treatment of inoperable CSCCs. In 2019, the PD1-antibody cemiplimab, has been approved for the treatment of locally advanced and metastatic CSCC by the European Medicines Agency. After 3 years of follow up, Cemiplimab shows overall response rates of 46 %, the median overall survival and median response rate had not been reached yet. Additional immunotherapeutics, combinations with other agents and oncolytic viruses are all potentially worth study to try, so clinical trial data will be forthcoming over the next few years to guide optimal use of these agents.

CONCLUSION

Multidisciplinary board decisions are mandatory for all patients with advanced disease who require more than surgery. Further development of existing therapeutic concepts, identification of new combination therapies and the development of new immunotherapeutics will be the key challenge over the next few years.

Das kutane Plattenepithelkarzinom – ein Update

Hintergrund Das kutane Plattenepithelkarzinom (PEK) ist nach dem Basalzellkarzinom der zweithäufigste bösartige Hauttumor. In Deutschland wurden 2014 über 50.000 PEK-Neuerkrankungen dokumentiert. Mit Zunahme der durchschnittlichen Lebenserwartung und Komorbiditäten treten mittlerweile auch gehäuft lokal fortgeschrittene Tumore mit Metastasierung auf.

Methode Selektive Literaturrecherche in PubMed und unter Berücksichtigung der deutschen S3-Leitlinien „Aktinische Keratosen und Plattenepithelkarzinom der Haut“ und „Prävention von Hautkrebs“.

Ergebnisse Beim PEK ist der Goldstandard die vollständige Exzision des Primärtumors mittels histopathologischer Kontrolle der Schnittränder. Eine Radiotherapie kann eingesetzt werden, wenn eine vollständige Exzision nicht erreicht werden kann bzw. Inoperabilität besteht. Im Falle eines metastasierten (mPEK) oder lokal fortgeschrittenen (laPEK) PEK, welches nicht kurativ operiert oder bestrahlt werden kann, werden systemische medikamentöse Therapien eingesetzt. Mit der Zulassung des PD1-Antikörpers Cemiplimab steht seit 2019 in der EU eine neue systemische Therapie zur Behandlung des fortgeschrittenen PEK zur Verfügung. Nach bis zu 3 Jahren Follow-up sprechen noch 46% der Patienten mit mPEK und laPEK auf Cemiplimab an, der Medianwert für das Gesamtüberleben und die Ansprechdauer ist in beiden Gruppe noch nicht erreicht. Weitere Antikörper gegen PD1 oder PDL1, Kombinationstherapien sowie die Immuntherapie mit onkolytischen Viren ermöglichen zahlreiche Therapieoptionen und sind aktuell Gegenstand der Forschung.

Schlussfolgerung Mit der Zunahme von fortgeschrittenen Stadien des PEK nimmt die Wichtigkeit des interdisziplinären Tumorboards für den Therapieentscheid immer mehr zu. Die Weiterentwicklung bestehender therapeutischer Konzepte, die Identifikation von gut wirksamen Kombinationstherapien sowie die Entwicklung weiterer verträglicher zielgerichteter Systemtherapien ist eine entscheidende dermatoonkologische Herausforderung der nächsten Jahre.

Cutaneous Squamous Cell Carcinoma: From Pathophysiology to Novel Therapeutic Approaches

Cutaneous squamous cell carcinoma (cSCC), a non-melanoma skin cancer, is a keratinocyte carcinoma representing one of the most common cancers with an increasing incidence. cSCC could be in situ (e.g., Bowen's disease) or an invasive form. A significant cSCC risk factor is advanced age, together with cumulative sun exposure, fair skin, prolonged immunosuppression, and previous skin cancer diagnoses. Although most cSCCs can be treated by surgery, a fraction of them recur and metastasize, leading to death. cSCC could arise de novo or be the result of a progression of the actinic keratosis, an in situ carcinoma. The multistage process of cSCC development and progression is characterized by mutations in the genes involved in epidermal homeostasis and by several alterations, such as epigenetic modifications, viral infections, or microenvironmental changes. Thus, cSCC development is a gradual process with several histological- and pathological-defined stages. Dermoscopy and reflectance confocal microscopy enhanced the diagnostic accuracy of cSCC. Surgical excision is the first-line treatment for invasive cSCC. Moreover, radiotherapy may be considered as a primary treatment in patients not candidates for surgery. Extensive studies of cSCC pathogenic mechanisms identified several pharmaceutical targets and allowed the development of new systemic therapies, including immunotherapy with immune checkpoint inhibitors, such as Cemiplimab, and epidermal growth factor receptor inhibitors for metastatic and locally advanced cSCC. Furthermore, the implementation of prevention measures has been useful in patient management.

Cytotoxic and targeted systemic therapy in patients with advanced cutaneous squamous cell carcinoma in the head and neck

BACKGROUND

The outcomes of patients treated with cytotoxic or targeted systemic therapy is not well defined for cutaneous squamous cell carcinoma of the head and neck (cSCCHN).

METHODS

Patients with cSCCHN treated with cytotoxic or targeted systemic therapy were included. Patients were divided into two groups based on the presence of distant metastasis (M1 vs. M0) at presentation. A proportional hazards model was used to assess for independent predictors of overall survival.

RESULTS

Of 129 patients with cSCCHN, 20 (16%) were M1 and 109 (84%) were M0. Independent predictors of improved survival were M0 status, treatment of locally advanced disease with radiotherapy, and lower Eastern Cooperative Oncology Group (ECOG) score.

CONCLUSIONS

Survival was worse in M1 patients treated with cytotoxic or targeted systemic therapy and poor baseline performance status but improved in those receiving radiotherapy. These data can serve as historical controls for future systemic therapy trials, including immunotherapy.

Medical treatment of advanced cutaneous squamous-cell carcinoma

Considering the rising incidence, cutaneous squamous-cell carcinoma (cSCC) has a high clinical relevance. In patients with localized cSCC, complete surgical resection is indicated. Radiotherapy should be performed in patients with non-resectable tumours or in patients who are not suitable for surgery. Systemic therapy is reserved for cSCC that are neither surgically nor radiotherapeutically curable due to their extensive local spread and/or local or distant metastasis. In the absence of prospective randomized phase 3 trials to evaluate and compare the efficacy and safety of chemotherapeutics, epidermal growth factor receptor (EGFR) inhibitors and anti-PD-1 antibodies, no final recommendation for systemic therapy can be given for patients with locally advanced or metastatic cSCC. Anti-PD-1 antibodies currently show promising results with response rates of up to 50% in both locally advanced and metastatic cSCC. Anti-PD-1 antibodies appear to achieve higher response rates compared with EGFR inhibitors, and the duration of response appears to be superior to both chemotherapy and EGFR inhibitors. Compared with chemotherapy, the side effect profile of anti-PD-1 antibodies appears to be favourable. Altogether, PD-1 inhibitors are expected to become the new standard of care for patients with locally advanced and metastatic cSCC. Currently, placebo-controlled clinical trials are investigating the adjuvant use of cemiplimab and pembrolizumab in patients undergoing resection and radiotherapy of high-risk cSCC. Patients not eligible for anti-PD-1 treatment, e.g. in organ transplant recipients, or in patients refractory to anti-PD-1 may be offered EGFR inhibitors and/or chemotherapies. Chemotherapies appear to be superior to EGFR inhibitors in terms of response rates, whereas EGFR inhibitors have a more favourable toxicity profile. EGFR inhibitors are therefore more suitable for multimorbid and/or frail elderly patients. By combining EGFR inhibitors with local therapy such as surgery or radiotherapy, response rates and duration of response may be improved.

Epidermal Growth Factor Receptor's Function in Cutaneous Squamous Cell Carcinoma and Its Role as a Therapeutic Target in the Age of Immunotherapies

OPINION STATEMENT

Recent studies have evidenced the potential of combining anti-EGFR therapies with anti-PD-1/PD-L1 checkpoint therapies. Both anti-EGFR and anti-PD-1/PD-L1 have been separately tested in the treatment of cutaneous SCC (cSCC). Here, we review recent data on EGFR in the context of cancer progression, as a prognostic and as a therapeutic target in cSCC. Anti-EGFR/checkpoint immunotherapy and other combination therapy approaches are discussed. With the advent of immunotherapy, EGFR is still a valid cSCC target.

Advanced cutaneous squamous cell carcinoma: real world data of patient profiles and treatment patterns

BACKGROUND

Cutaneous squamous cell carcinoma (cSCC) is one of the most common types of cancer in the Caucasian population, with an increasing incidence. cSCC is mostly a local invasive disease that can be treated surgically in the majority of the cases. However, in the case of advanced cSCC (acSCC), a multimodality approach also involving systemic therapies needs to be considered.

METHODS

One hundred and ninety-five patients diagnosed with acSCC (stages III and IV) treated in our centre between 2011 and 2018 were included. Patient and tumour characteristics along with treatment patterns were documented and analyzed. Descriptive analysis was performed and survival rates were estimated according to Kaplan-Meier and compared with the Log-rank test. Follow-up was defined as the time between diagnosis of advanced disease and last contact or death. All causes of death were considered as events.

RESULTS

The median follow-up was 21 months [IQR = (10.0; 21.0)]. The median age at time of advanced disease diagnosis was 78 years [IQR = (72; 84)], with 40.5% of the patients in stage III and 59.5% in stage IV. One hundred and forty-five patients had resectable tumours. In this group the median overall survival (mOS) was 59 months (95% CI: 28.2-89.8), significantly higher than the mOS in patients with inoperable tumour [n = 50; mOS: 19 months (96% CI: 7-31, P <0.0001)]. Patients receiving immunotherapy (n = 20) showed a statistically significant better survival compared to those treated with other systemic therapies (n = 37; mOS not reached vs. mOS: 22 months (95% CI: 6.5-43.5), P = 0.034). For patients without systemic therapy, a combination of surgery and radiotherapy provided better outcomes compared to radiotherapy alone or best supportive care (P <0.001).

CONCLUSION

Surgical complete resection should be the first therapeutic option for patients with acSCC. For patients with inoperable tumour, first-line immunotherapy should be preferably considered.

Stage IV cutaneous squamous cell carcinoma: treatment outcomes in a series of 42 patients

BACKGROUND

The prevalence and incidence of cutaneous squamous cell carcinoma (cSCC) are increasing due to the ageing of the population and sun exposure. Advanced cSCC forms (locally advanced and/or locoregional metastatic and/or distant metastatic) account for approximately 3% of cSCC and can result in death.

OBJECTIVE

Analysis of the clinical characteristics and treatment outcomes in stage IV cSCC with unresectable locoregional extension and/or the presence of metastases.

METHODS

A retrospective study was conducted at a single-centre university hospital for stage IV cSCC patients followed between 1 January 2008 and 31 December 2015. Descriptive analyses (demographic, anatomo-clinical characteristics, treatment sequences, response to treatment and survival analysis) were performed.

RESULTS

The study included 42 patients (median age = 75.5 years) with a diagnosis of stage IV cSCC who were treated with at least one line of chemotherapy and/or cetuximab. At the time of diagnosis, 85.7% of the patients had locoregional extension (19% of locally advanced and 67% of locoregional metastatic) and 14.3% had distant metastatic disease. Regarding treatment, 40% and 36% of patients received no more than 1 and 2 systemic treatment lines, respectively. The 4-year overall survival was 6%, and the median follow-up was 18.6 months. The objective response rate was 55% after the first line of treatment with a median progression-free survival (PFS) of 6.18 months and 12% after the second line with a median PFS of 6.51 months. Grade 3 and 4 adverse events were observed for 33% of patients.

CONCLUSION

Our study confirms a very poor prognosis of stage IV cSCC and a poor response to conventional therapies, indicating that the stage IV cSCC patient population remains with unmet medical needs.

Actinic Keratosis and Cutaneous Squamous Cell Carcinoma

BACKGROUND

Cutaneous squamous cell carcinoma (cSCC) and its precursors, actinic keratoses (AK), are common. Physicians of multiple specialties are confronted with their treatment.

METHODS

This review is based on publications retrieved by a selective search in PubMed, as well as on the German guidelines on AK and cSCC, skin cancer prevention, and surgery with histologic guidance.

RESULTS

Local treatments for AK include lesional cryotherapy, curettage, and laser ablation as well as field-directed treatments with topical agents, e.g., diclofenac plus hyaluronic acid, imiquimod, 5-fluorouracil, ingenol mebutate, and photodynamic therapy. These treatments can be administered in various sequences or combinations, depending on individual factors and the stage of the disease. The gold standard of treatment for cSCC is histologically confirmed complete resection; radiotherapy is an alternative. Locally uncontrollable or metastatic disease is treated with systemic drugs. The use of various chemotherapeutic agents, EGFR-directed therapies, and the PD-I inhibitor cemiplimab, either singly or in combination, has been described in uncontrolled trials and case series. Cemiplimab has a reported response rate of 47% and was recently approved for the treatment of advanced cSCC.

CONCLUSION

There are many options for the treatment of AK and cSCC that must be considered in the interdisciplinary care of these entities.

Wnt Signaling Pathways in Keratinocyte Carcinomas

The skin functions as a barrier between the organism and the surrounding environment. Direct exposure to external stimuli and the accumulation of genetic mutations may lead to abnormal cell growth, irreversible tissue damage and potentially favor skin malignancy. Skin homeostasis is coordinated by an intricate signaling network, and its dysregulation has been implicated in the development of skin cancers. Wnt signaling is one such regulatory pathway orchestrating skin development, homeostasis, and stem cell activation. Aberrant regulation of Wnt signaling cascades not only gives rise to tumor initiation, progression and invasion, but also maintains cancer stem cells which contribute to tumor recurrence. In this review, we summarize recent studies highlighting functional evidence of Wnt-related oncology in keratinocyte carcinomas, as well as discussing preclinical and clinical approaches that target oncogenic Wnt signaling to treat cancers. Our review provides valuable insight into the significance of Wnt signaling for future interventions against keratinocyte carcinomas.

Uncommon Presentation of Metastatic Squamous Cell Carcinoma of the Skin and Treatment Challenges

Patient: Female, 80

Final Diagnosis: Metastatic squamous cell carcinoma of skin

Symptoms: Back pain • leg swelling • uti

Medication: —

Clinical Procedure: Immunotherapy

Specialty: Oncology

Current Basal and Squamous Cell Skin Cancer Management

LEARNING OBJECTIVES

After studying this article, the participant should be able to: 1. Characterize basal and squamous cell carcinomas as low or high risk based on size, location, histology, and clinical features. 2. Understand appropriate surgical margins in low- and high-risk lesions, and other management options, including Mohs micrographic surgery, electrodissection and curettage, topical agents, cryotherapy, photodynamic therapy, and radiation therapy. 3. Discuss adjuvant therapies for locally advanced and metastatic disease, including radiation therapy, chemotherapy, and targeted therapies such as hedgehog pathway inhibitors. 4. Educate patients on preventive measures such as skin examinations, sun protection, oral retinoids, and oral nicotinamide (vitamin B3). 5. Devise a reconstructive plan once clear oncologic margins are obtained.

SUMMARY

With the growing incidence of basal and squamous cell carcinoma, there is an increasing demand for appropriate oncologic management and aesthetic reconstruction. The goal of this CME article is to provide a foundation of knowledge to accurately diagnose, stage, and treat nonmelanoma skin cancers. In addition, it provides the practicing plastic surgeon alternate tools for managing these skin lesions, including topical agents, destructive therapies, and radiation therapy. Lastly, reconstructive plans for selected soft-tissue defects are discussed.

Isolated limb perfusion for unresectable extremity cutaneous squamous cell carcinoma; an effective limb saving strategy

Background

A small minority of patients present with locally advanced cutaneous Squamous Cell Carcinoma (cSCC). The aim of this study was to evaluate the effectiveness of Tumour necrosis factor α (TNF) and melphalan based isolated limb perfusion (TM-ILP) as a limb saving strategy for locally advanced extremity cSCC.

Methods

A retrospective search from prospectively maintained databases, at two tertiary referral centers, was performed to identify patients treated with TM-ILP for locally advanced cSSC of an extremity between 2000 and 2015.

Results

A total of 30 patients treated with TM-ILP for cSCC were identified, with a median age of 71 years (36–92) and 50% female. Response could not be evaluated in 3 patients. After a median follow up of 25 months, the overall response rate was 81% (n = 22), with 16 patients having a complete response (CR, 59%). A total of 7 patients developed local recurrence, with a median time to recurrence of 9 months (Interquartile Range 7–10). Progressive disease was observed in 5 patients (19%). Limb salvage rate was 80%. The overall 2-year survival was 67%.

Conclusions

TM-ILP should be considered as an option in patients with locally advanced cSCC in specialised centers, resulting in a high limb salvage rate.

Novel Therapeutic Targets in Cutaneous Squamous Cell Carcinoma

Cutaneous squamous cell carcinoma (SCC) is one of the common cancers in Caucasians, accounting for 20–30% of cutaneous malignancies. The risk of metastasis is low in most patients; however, aggressive SCC is associated with very high mortality and morbidity. Although cutaneous SCC can be treated with surgical removal, radiation and chemotherapy singly or in combination, the prognosis of patients with metastatic SCC is poor. Recently, the usage of immune checkpoint blockades has come under consideration. To develop effective therapies that are less toxic than existing ones, it is crucial to achieve a detailed characterization of the molecular mechanisms that are involved in cutaneous SCC pathogenesis and to identify new drug targets. Recent studies have identified novel molecules that are associated with SCC carcinogenesis and progression. This review focuses on recent advances in molecular studies involving SCC tumor development, as well as in new therapeutics that have become available to clinicians.

Developments in the treatment of locally advanced and metastatic squamous cell carcinoma of the skin: a rising unmet need

Squamous cell carcinoma of the skin (SCCS) is a common malignancy with potentially devastating consequences in patients with locally advanced or metastatic disease. Its rising incidence, primarily a result of an aging population and increased ultraviolet (UV) radiation exposure, characterize an emerging unmet need. A firm understanding of the biology of this disease, likely distinct from that of other squamous malignancies because of the influence of UV radiation, is necessary in the evaluation of treatment paradigms. Careful recognition of high-risk features pertaining to tumor and host characteristics is paramount to proper management. However, a lack of standardization in guidelines in this regard creates a challenge for physicians. Questions persist regarding additional evaluation and treatment for advanced disease such as the roles for sentinel lymph node biopsy and the adjuvant use of radiation and chemotherapy. With respect to advanced disease, multiple combinations of chemotherapy have been tested with variable success, but no rigorous randomized studies have been conducted. In addition, EGFR inhibitors such as cetuximab and erlotinib have displayed antitumor activity and as such, warrant further investigation. In sum, the treatment of locally advanced and metastatic SCCS is a ripe area for clinical investigation. This article summarizes the current understanding of disease biology and emerging questions in the management of this disease.