Vismodegib in patients with advanced basal cell carcinoma: Primary analysis of STEVIE, an international, open-label trial

Personalized treatment concepts in extraocular cancer

Background

The periocular skin is neoplasms-prone to various benign and malignant. Periocular malignancies are more aggressive and challenging to cure and repair than those in other skin areas. In recent decades, immunotherapy has significantly advanced oncology, allowing the autoimmune system to target and destroy malignant cells. Skin malignancies, especially periocular tumors, are particularly sensitive to immunotherapy. This technique has dramatically impacted the successful treatment of challenging tumors.

Main text

Extraocular cancers, including eyelid (basal cell carcinoma, squamous cell carcinoma, melanoma, merkel cell carcinoma), conjunctival tumors (conjunctival melanoma, ocular surface squamous neoplasia) and other rare tumors, are unique and challenging clinical situations. Several genetic alterations associated with the pathogenesis of these diseases have been identified, and molecular mechanism are essential for the development of the immunotherapy agents, such as Hedgehog pathway inhibitors (vismodegib and sonidegib) for basal cell carcinoma, BRAF/MEK inhibitors (vemurafenib, dabrafenib, and encorafenib) for melanoma, and immune checkpoint inhibitors (Avelumab, pembrolizumab) for Merkel cell carcinoma.

Conclusions

The optimal treatment for periocular skin cancer depends on the type and size of the tumor and whether it involves orbital and adnexal structures. Adjuvant and neoadjuvant therapy with chemotherapy-targeted therapies and immune checkpoint inhibitors should be considered based on tumor type, tumor molecular profile, expected response rate, and candidacy for systemic treatment.

Treatments on the horizon for locally advanced basal cell carcinoma

Basal cell carcinoma (BCC) is one of the most common human cancers. Most cases of BCC are amenable to surgical and topical treatments with excellent prognosis if diagnosed timely and managed appropriately. However, in a small percentage of cases, it could be locally advanced BBC (laBCC) and not amenable to surgery or radiation, including recurrent, large tumors or tumors that invade deeper tissue. Hedgehog inhibitors (vismodegib and sonidegib) are approved as the first-line treatment of laBCC. PD-1 inhibitor immunotherapy (cemiplimab) is indicated for cases that progressed on or could not tolerate hedgehog inhibitors or when hedgehog inhibitors are contraindicated. Given the modest response and bothersome side effects of some of the agents above, there are reports of novel treatments, and clinical trials are currently evaluating multiple agents.

Hedgehog pathway inhibitors for locally advanced and metastatic basal cell carcinoma: A real-world single-center retrospective review

Basal cell carcinoma (BCC) is highly curable by surgical excision or radiation. In rare cases, BCC can be locally destructive or difficult to surgically remove. Hedgehog inhibition (HHI) with vismodegib or sonidegib induces a 50-60% response rate. Long-term toxicity includes muscle spasms and weight loss leading to dose decreases. This retrospective chart review also investigates the impact of CoQ10 and calcium supplementation in patients treated with HHI drugs at a single academic medical center from 2012 to 2022. We reviewed the charts of adult patients diagnosed with locally advanced or metastatic BCC treated with vismodegib or sonidegib primarily for progression-free survival (PFS). Secondary objectives included overall survival, BCC-specific survival, time to and reasons for discontinuation, overall response rate, safety and tolerability, use of CoQ10 and calcium supplements, and insurance coverage. Of 55 patients assessable for outcome, 34 (61.8%) had an overall clinical benefit, with 25 (45.4%) having a complete response and 9 (16.3%) a partial response. Stable disease was seen in 14 (25.4%) and 7 (12.7%) progressed. Of the 34 patients who responded to treatment, 9 recurred. Patients who were rechallenged with HHI could respond again. The median overall BCC-specific survival rate at 5 years is 89%. Dose reductions or discontinuations for vismodegib and sonidegib occurred in 59% versus 24% of cases, or 30% versus 9% of cases, respectively. With CoQ10 and calcium supplementation, only 17% required a dose reduction versus 42% without. HHI is highly effective for treating advanced BCC but may require dosing decreases. Sonidegib was better tolerated than vismodegib. CoQ10 and calcium supplementation can effectively prevent muscle spasms.

Japanese Dermatological Association guidelines: Outlines of Japanese clinical guidelines for basal cell carcinoma 2021

To summarize the current therapies for skin cancers, the Japanese Skin Cancer Society issued the first guidelines for skin cancers, including melanoma, squamous cell carcinoma, basal cell carcinoma (BCC), and extramammary Paget's disease, in 2007. These guidelines were revised in 2015. Herein, we present the English version of the 2021 edition of the Japanese clinical guidelines for BCC. In the latest edition, all procedures were performed according to the Grading of Recommendations, Assessment, Development and Evaluation systems. The clinical questions that could not be answered were selected for further analysis. A comprehensive literature search, systematic review, and recommendations for each clinical question were determined by a multidisciplinary expert panel comprising dermatologists, a plastic and reconstructive surgeon, and a pathologist. Surgical resection is the gold-standard therapy of BCC. Radiotherapy or topical treatments, other than surgical resection, have been used in some cases. Patients with unresectable or metastatic BCC require systemic therapy. Novel agents, such as immune response modifiers or hedgehog pathway inhibitors, are emerging worldwide for the treatment of BCC. Based on these viewpoints, four relevant clinical questions regarding, surgical resection, radiotherapy, topical treatment, and systemic therapy, were raised in this report that aims to help clinicians select suitable therapies for their patients.

Recent advances in cancer-associated fibroblast: Biomarkers, signaling pathways, and therapeutic opportunities

ABSTRACT

Anti-cancer therapies usually focus on tumor cells, but non-tumor stromal components in the tumor microenvironment also play vital roles in tumor initiation and progression, which may be the prognostic factors and potential therapeutic targets. Cancer-associated fibroblasts (CAFs) are the essential component in the tumor environment, exhibiting high heterogeneity in their cell origin and phenotype with diverse functions that influence tumor angiogenesis, immune systems, and metabolism. Single-cell RNA sequencing and genetically engineered mouse models have increased our understanding of CAF diversity, and many subtypes have been defined. However, the precise functions of these subtypes need to be studied and validated. Studies of signaling pathways and epigenetic changes in CAFs facilitate understanding of the phenotypes of CAFs and the crosstalk between tumor cells and CAFs to provide potential therapeutic targets. Some clinical trials, including phase III trials targeting CAFs, have been performed recently. However, few of these trials have generated promising results, which indicates that the complexity of CAFs in the tumor microenvironment remains largely unknown, and in-depth investigations of CAFs should be performed. This review summarizes the research on CAFs, focusing on the heterogeneity of their phenotypes and functions, specific signaling pathways, and the therapeutic strategies involving CAFs. Additionally, we briefly discuss the current technologies commonly used in CAF studies and describe the challenges and future perspectives of CAF research.

Review of recent advances in managing periocular skin malignancies

Management of cutaneous malignancies can be particularly challenging when they are located in the periocular region. The standard of care for localized disease is complete surgical excision, but this may not be possible without significant disruption to visual structures and facial appearance. Definitive radiation may be an option for some patients who cannot or do not wish to undergo surgery. Advances in systemic treatment options for locally advanced and metastatic skin cancers in the past 10 years have prompted investigation into neoadjuvant treatment of periocular cancers. The use of chemotherapy, immune checkpoint inhibitors, and targeted therapies have all been reported with varying degrees of success. For many patients, targeted therapies or immune checkpoint inhibitors should be considered depending on the cancer type, symptoms, and goals with the input of a multidisciplinary cancer care team. In this article, we systematically review the latest updates in surgical, radiotherapeutic, and medical management of periocular malignancies.

Updates on eyelid cancers

In this review, we aim to provide an overview of the five most common malignant eyelid tumors with current treatment recommendations based on international guidelines. Particular attention is paid to the clinicopathological correlation and the update with regard to adequate treatment. Newer systemic therapies enrich the existing treatment options, of which complete tumor excision remains the most important therapeutic measure.

Exploring vismodegib: A non-surgical breakthrough in the management of advanced periocular basal cell carcinoma

The management of periocular basal cell carcinoma (BCC) is challenging due to its proximity to the eyeball. Vismodegib, a Hedgehog pathway inhibitor, has emerged as a therapeutic option for locally advanced and metastatic BCC. To critically appraise the relevant evidence, we conducted a systematic review of observational and experimental studies assessing the efficacy and safety of vismodegib for periocular BCC. Thirty-seven trials, including 435 patients, were eligible. No randomized trials were retrieved. Complete and overall clinical response rates were 20-88 % and 68-100 %, respectively. Disease progression was observed at a maximum rate of 14 %. Recurrence rates varied between 0 % and 31 %. The most common side effects were muscle cramps, dysgeusia, weight loss and alopecia. Treatment with vismodegib improved health-related quality of life. In conclusion, vismodegib represents an important novel treatment for advanced periocular BCC, with good response rates and acceptable tolerability profile. Nevertheless, its full potential needs clarification through randomized controlled trials.

Final analysis of phase II results with cemiplimab in metastatic basal cell carcinoma after hedgehog pathway inhibitors

BACKGROUND

Metastatic basal cell carcinoma (mBCC) is a rare condition with no effective second-line treatment options. Cemiplimab is an immune checkpoint inhibitor that blocks the binding of programmed cell death-1 (PD-1) to its ligands, programmed death-ligand 1 (PD-L1) and programmed death-ligand 2 (PD-L2). Here, we present the final analysis of cemiplimab in patients with mBCC after first-line hedgehog pathway inhibitor (HHI) treatment (NCT03132636).

PATIENTS AND METHODS

In this open-label, single-arm, phase II study, adults with mBCC and Eastern Cooperative Oncology Group performance status ≤1, post-HHI treatment, received cemiplimab 350 mg intravenously every 3 weeks for ≤93 weeks or until disease progression or unacceptable toxicity. The primary endpoint was objective response rate (ORR) by independent central review (ICR). Duration of response (DOR) was a key secondary endpoint. Other secondary endpoints were ORR per investigator assessment, progression-free survival (PFS), overall survival (OS), complete response rate, safety, and tolerability.

RESULTS

Fifty-four patients were enrolled: 70% were male and the median age of patients was 64 [interquartile range (IQR) 57.0-73.0] years. The median duration of follow-up was 8 months (IQR 4-21 months). The ORR per ICR was 22% [95% confidence interval (CI) 12% to 36%], with 2 complete responses and 10 partial responses. Among responders, the median time to response per ICR was 3 months (IQR 2-7 months). The estimated median DOR per ICR was not reached [95% CI 10 months-not evaluable (NE)]. The disease control rate was 63% (95% CI 49% to 76%) per ICR and 70% (95% CI 56% to 82%) per investigator assessment. The median PFS per ICR was 10 months (95% CI 4-16 months); the median OS was 50 months (95% CI 28 months-NE). The most common treatment-emergent adverse events were fatigue [23 (43%)] and diarrhoea [20 (37%)]. There were no treatment-related deaths.

CONCLUSIONS

Cemiplimab demonstrated clinically meaningful antitumour activity, including durable responses, and an acceptable safety profile in patients with mBCC who had disease progression on or intolerance to HHI therapy.

Oncofetal reprogramming in tumor development and progression: novel insights into cancer therapy

Emerging evidence indicates that cancer cells can mimic characteristics of embryonic development, promoting their development and progression. Cancer cells share features with embryonic development, characterized by robust proliferation and differentiation regulated by signaling pathways such as Wnt, Notch, hedgehog, and Hippo signaling. In certain phase, these cells also mimic embryonic diapause and fertilized egg implantation to evade treatments or immune elimination and promote metastasis. Additionally, the upregulation of ATP-binding cassette (ABC) transporters, including multidrug resistance protein 1 (MDR1), multidrug resistance-associated protein 1 (MRP1), and breast cancer-resistant protein (BCRP), in drug-resistant cancer cells, analogous to their role in placental development, may facilitate chemotherapy efflux, further resulting in treatment resistance. In this review, we concentrate on the underlying mechanisms that contribute to tumor development and progression from the perspective of embryonic development, encompassing the dysregulation of developmental signaling pathways, the emergence of dormant cancer cells, immune microenvironment remodeling, and the hyperactivation of ABC transporters. Furthermore, we synthesize and emphasize the connections between cancer hallmarks and embryonic development, offering novel insights for the development of innovative cancer treatment strategies.

Co-targeting FAK and Gli1 inhibits the tumor-associated macrophages-released CCL22-mediated esophageal squamous cell carcinoma malignancy

Esophageal squamous cell carcinoma (ESCC) is a frequently seen esophageal tumor type in China. Activation of signaling proteins and relevant molecular mechanisms in ESCC are partially explored, impairing the antitumor efficiency of targeted therapy in ESCC treatment. Tumor-associated macrophages (TAMs)-released C-C motif chemokine 22 (CCL22) can activate intratumoral focal adhesion kinase (FAK), thus promoting the progression of ESCC. Here, we demonstrated that highly secreted CCL22 by TAMs (CCL22-positive TAMs) induced ESCC cell stemness and invasion through facilitating transcriptional activity of intratumoral glioma-associated oncogene 1 (Gli1), a downstream effector for Hedgehog (HH) pathway. Mechanistically, FAK-activated protein kinase B (AKT) mediated Gli1 phosphorylation at its Ser112/Thr115/Ser116 sites and released Gli1 from suppressor of fused homolog, the endogenous inhibitor of Gli1 to activate downstream stemness-associated factors, such as SRY-box transcription factor 2 (SOX2), Nanog homeobox (Nanog), or POU class 5 homeobox (OCT4). Furthermore, inhibition of FAK activity by VS-4718, the FAK inhibitor, enhanced antitumor effect of GDC-0449, the HH inhibitor, both in xenografted models and in vitro assays. Clinically, CCL22/Gli1 axis is used to evaluate ESCC prognosis. Overall, our study establishes the communication of FAK with HH pathway and offers the novel mechanism related to Gli1 activation independent of Smoothened as well as the rationale for the anti-ESCC combination treatment.

Signaling Pathways and Therapeutic Strategies in Advanced Basal Cell Carcinoma

Non-melanoma skin cancers (NMSCs) are the most common human neoplasms world-wide. In detail, basal cell carcinoma (BCC) is the most frequent malignancy in the fair-skinned population. The incidence of BCC remains difficult to assess due to the poor registration practice; however, it has been increasing in the last few years. Approximately, 85% of sporadic BCCs carry mutations in Hedgehog pathway genes, especially in PTCH, SUFU and SMO genes, which lead to the aberrant activation of GLI transcriptional factors, typically silent in cells of adult individuals. The management of advanced BCC (aBCC), both metastatic (mBCC) and locally advanced BCC (laBCC), not candidates for surgical excision or radiotherapy, remains challenging. The discovery of mutations in the Hh signaling pathway has paved the way for the development of Hh pathway inhibiting agents, such as vismodegib and sonidegib, which have represented a breakthrough in the aBCC management. However, the use of these agents is limited by the frequent occurrence of adverse events or the development of drug resistance. In this review, we thoroughly describe the current knowledge regarding the available options for the pharmacological management of aBCCs and provide a forward-looking update on novel therapeutic strategies that could enrich the therapeutic armamentarium of BCC in the near future.

Immunotherapy and Its Timing in Advanced Basal Cell Carcinoma Treatment

For patients with advanced basal cell carcinoma (BCC), including locally advanced or metastatic BCC not amenable to curative surgery or radiotherapy, hedgehog pathway inhibitors (HHI) vismodegib and sonidegib are approved as first-line systemic treatment. Results from clinical trials highlight that the overall discontinuation rate of HHI treatment varies from 88% to 92% with vismodegib and is approximately 92% with sonidegib, and half of patients will discontinue HHI after approximately 8 to 12 months. The main factors weighing in on the decision to discontinue HHI include efficacy (tumor response), adverse events and patient decision. In clinical practice, some of the patients that stop HHI may be re-evaluated if the tumor becomes amenable to surgery, or restart HHI at a later time, while others will need to switch to immunotherapy, depending on the reasons for HHI discontinuation. In this review, we revisit the therapeutic decisions considering a switch from HHI to immunotherapy with anti-PD-1 agent cemiplimab and we highlight the place of cemiplimab in the therapeutic ladder for patients with advanced BCC. We discuss the evidence on the efficacy and safety of anti-PD-1 agents as second-line systemic monotherapy, or in combination with other treatments, and the emergence of checkpoint immunotherapy as a neoadjuvant treatment.

European consensus-based interdisciplinary guideline for diagnosis and treatment of basal cell carcinoma-update 2023

Basal cell carcinoma (BCC) is the most common malignant tumour in white populations. Multidisciplinary experts from European Association of Dermato-Oncology (EADO), European Dermatology Forum, European Society for Radiotherapy and Oncology (ESTRO), Union Européenne des Médecins Spécialistes, and the European Academy of Dermatology and Venereology developed updated recommendations on diagnosis and treatment of BCC. BCCs were categorised into 'easy-to-treat' (common) and 'difficult-to-treat' according to the new EADO clinical classification. Diagnosis is based on clinico-dermatoscopic features, although histopathological confirmation is mandatory in equivocal lesions. The first-line treatment of BCC is complete surgery. Micrographically controlled surgery shall be offered in high-risk and recurrent BCC, and BCC located on critical anatomical sites. Topical therapies and destructive approaches can be considered in patients with low-risk superficial BCC. Photodynamic therapy is an effective treatment for superficial and low-risk nodular BCCs. Management of 'difficult-to-treat' BCCs should be discussed by a multidisciplinary tumour board. Hedgehog inhibitors (HHIs), vismodegib or sonidegib, should be offered to patients with locally advanced and metastatic BCC. Immunotherapy with anti-PD1 antibodies (cemiplimab) is a second-line treatment in patients with a progression of disease, contraindication, or intolerance to HHI therapy. Radiotherapy represents a valid alternative in patients who are not candidates for or decline surgery, especially elderly patients. Electrochemotherapy may be offered when surgery or radiotherapy is contraindicated. In Gorlin patients, regular skin examinations are required to diagnose and treat BCCs at an early stage. Long-term follow-up is recommended in patients with high-risk BCC, multiple BCCs, and Gorlin syndrome.

Targeted therapy and immunotherapy for orbital and periorbital tumors: a major review

Traditionally, for patients who are poor candidates for surgery and/or radiotherapy, palliative chemotherapy is often offered but with significant toxic side effects. However, recent advancements in our understanding of tumor biology and molecular genetics have brought new understanding to the molecular pathways of certain tumors and cancers. This has ushered in a new era of precision medicine specific to a tumor or cancer treatment pathway (targeted therapy) or directed to host-tumor responses (immunotherapy). This article will focus on recent updates in the application of available targeted and immunotherapy for managing orbital and periorbital tumors and tumor-like conditions, which include cutaneous basal cell carcinoma, cutaneous squamous cell carcinoma, cutaneous melanoma, Merkel cell carcinoma, sebaceous gland carcinoma, solitary fibrous tumor, dermatofibrosarcoma protuberans, orbital meningioma, neurofibromatosis, Langerhans cell histiocytosis, ocular adnexal lymphoma, orbital lymphatic malformation, and adenoid cystic carcinoma.

Long-term strategies for management of advanced basal cell carcinoma with hedgehog inhibitors

Basal cell carcinoma (BCC), the most common type of skin cancer, is characterized by aberrant activation of the hedgehog molecular pathway. Systemic therapy is indicated when local approaches, such as surgery and radiation, are inappropriate. In this article, a group of clinical experts recommends the long-term management strategy for advanced BCC patients treated with systemic therapy. The hedgehog inhibitors sonidegib and vismodegib are first-line treatments for advanced BCC with a long-lasting response, but long-term treatment with hedgehog inhibitors is often challenged by tolerability issues. However, several strategies for adverse effect management are available, such as dose interruptions, on-label alternate-day dosing and supportive medications. In conclusion, although BCC shows a high tumor mutational burden that favors a response to immunotherapy, experts recommend keeping patients on hedgehog inhibitors limiting immunotherapy to those who developed resistance during hedgehog inhibitor therapy or in case of persisting toxicity despite long-term management of adverse events.

Cellular and molecular mechanisms of Hedgehog signalling

The Hedgehog signalling pathway has crucial roles in embryonic tissue patterning, postembryonic tissue regeneration, and cancer, yet aspects of Hedgehog signal transmission and reception have until recently remained unclear. Biochemical and structural studies surprisingly reveal a central role for lipids in Hedgehog signalling. The signal - Hedgehog protein - is modified by cholesterol and palmitate during its biogenesis, thereby necessitating specialized proteins such as the transporter Dispatched and several lipid-binding carriers for cellular export and receptor engagement. Additional lipid transactions mediate response to the Hedgehog signal, including sterol activation of the transducer Smoothened. Access of sterols to Smoothened is regulated by the apparent sterol transporter and Hedgehog receptor Patched, whose activity is blocked by Hedgehog binding. Alongside these lipid-centric mechanisms and their relevance to pharmacological pathway modulation, we discuss emerging roles of Hedgehog pathway activity in stem cells or their cellular niches, with translational implications for regeneration and restoration of injured or diseased tissues.

[Current Management of Basal Cell Carcinoma]

For the management of basal cell carcinoma, the primary performance of a risk stratification, which is decisive for the further diagnostic and therapeutic steps, is becoming increasingly important.Various non-invasive methods are available to confirm the clinical diagnosis. Histological confirmation of the diagnosis is recommended in unclear cases. In poorly displaced lesions, preoperative cross-sectional imaging of the tumor area should be performed to exclude osseous infiltration.The gold standard in treatment remains surgery, which should be performed by means of micrographically controlled surgery if possible. In addition, there are other therapeutic methods such as radiotherapy or a number of topical therapy options (photodynamic therapy, cryotherapy or application of 5-fluorouracil or imiquimod), which can be used in certain cases. Also for advanced or metastatic basal cell carcinoma, effective drugs are available in the form of the hedgehog inhibitors, for which there is now several years of application experience with regard to efficacy and handling of adverse events. With the PD-1 inhibitor cemiplimab, a further therapeutic option for non-operable or metastatic tumors has been available since June 2021.The most important preventive measure is consistent textile or chemical UV protection in already affected individuals. In addition, nicotinamide and celecoxib can be used orally for prevention. For follow-up, the current S2k guideline recommends regular self-monitoring and standardized medical check-ups.

An update on the current and emerging pharmacotherapies for basal cell carcinomas

INTRODUCTION

Despite surgical approach is still the mainstay for basal cell carcinoma (BCC) management, several issues may limit the use of this technique, leading to the need for new treatments to offer patients a personalized approach.

AREAS COVERED

A comprehensive review of the available and emerging pharmacologic strategies for BCC management, including mechanisms of action, and potential adverse effects, has been performed to provide with an up-to-date manuscript on the current treatment scenario of BCC. Globally, targeting the Sonic-Hedgehog pathway is one of the main mechanisms of action of currently investigated drugs. Other alternatives are based on the concept of an enhancement of the immune response such as immune checkpoint inhibitors, or intra-tumor treatments.

EXPERT OPINION

Although low-risk BCCs are often treated with destructive methods or topical treatments, surgery is the mainstay of treatment for the majority of BCCs. However, several factors may limit the use of surgery in BCC management. Recently, major knowledge on BCCs pathogenesis has led to the development of effective and selective drugs. In our opinion, soon many drugs will be licensed, allowing clinicians to offer patients with BCC the right treatment at the right moment. Certainly, further studies are needed.

Surgery in the Era of Immunotherapy for Advanced Head and Neck Non-melanoma Skin Cancer

PURPOSE OF REVIEW

Surgery remains the mainstay of treatment for non-melanoma skin cancer (NMSC). Immunotherapy (IO) has emerged as an alternative option. This review provides a contemporary summary of how to incorporate IO into the management of advanced NMSC. Evidence-based outcomes and recent clinical trials are provided with emphasis on the three most common NMSC diagnoses: cutaneous squamous cell carcinoma (cSCC), basal cell carcinoma (BCC), and merkel cell carcinoma (MCC).

RECENT FINDINGS

Surgical resection while preserving form and function remains the standard of care for the majority of NMSCs. In recalcitrant cases failing traditional surgery and/or primary radiation, patient ineligible for such treatments, or unresectable disease, IO has emerged as a promising alternative. In the majority of cases, it is a supplanting primary chemotherapy. Surgery remains the standard of care for NMSC. Immunotherapy has emerged as an alternative option for non-surgical candidates and as a neoadjuvant means to minimize morbidity.

Pharmacokinetics and pharmacodynamics of Hedgehog pathway inhibitors used in the treatment of advanced or treatment-refractory basal cell carcinoma

INTRODUCTION

Sonidegib and vismodegib are currently the only US Food and Drug Administration and European Medicines Agency-approved small-molecule Hedgehog pathway inhibitors (HHIs)for treating adults with advanced or refractory basal cell carcinoma (BCC) that is not amenable to conventional surgery or radiotherapy. At this time, there are no head-to-head clinical trials comparing these two HHIs for efficacy and safety to assist clinicians with determining which HHI may be best suited for their patients.

AREAS COVERED

This review briefly describes the pathogenesis of BCC, provides a detailed overview of the key pharmacokinetic profile differences between sonidegib and vismodegib, explains their pharmacodynamics, and highlights the therapeutic considerations when either HHI is used to treat special patient populations.

EXPERT OPINION

Although both HHIs act at the same molecular target in the Hedgehog pathway, there are significant differences in their pharmacokinetic profiles that may play a potential role in their efficacy and safety. Evidence-based recommendations serve to inform clinicians until direct comparative clinical trials of sonidegib versus vismodegib are conducted to determine the clinical relevance of the reported differences in their pharmacokinetic properties.

Clinical Characteristics of an Italian Patient Population with Advanced BCC and Real-Life Evaluation of Hedgehog Pathway Inhibitor Safety and Effectiveness

BACKGROUND

Advanced basal cell carcinoma (aBCC) represents a complex and clinically heterogeneous group of lesions for which curative surgery and/or radiotherapy is unlikely. Systemic therapy with hedgehog pathway inhibitors (HHIs) changed the treatment landscape for this complex patient population.

OBJECTIVES

The aims of the present study are to describe the clinical characteristics of a real-life Italian cohort diagnosed with aBCC and to investigate effectiveness and safety of HHI.

METHODS

A multicenter observational study was performed by twelve Italian centers in the period January 1, 2016 - October 15, 2022. Patients aged ≥18 years and diagnosed with aBCC (locally advanced [laBCC] and metastatic BCC [mBCC]) were eligible for the study. Methods for investigating tumor response to HHI included clinical and dermatoscopic evaluation, radiological imaging, and histopathology. For HHI safety assessment, therapy-related adverse events (AEs) were reported and graded according to the Common Terminology Criteria for Adverse Events (CTCAE) version 5.0.

RESULTS

We enrolled 178 patients under treatment with HHI: 126 (70.8%) and 52 patients (29.2%) received sonidegib and vismodegib, respectively. Comprehensive data on HHI effectiveness and disease outcome were available for 132 (74.1%) of 178 patients: 129 patients had a diagnosis of laBCC (n = 84, sonidegib; n = 45, vismodegib) and 3 patients of mBCC (n = 2, vismodegib; n = 1, sonidegib, off-label). Objective response rate was 76.7% (95% confidence interval [CI]: 82.3-68.7) and 33.3% (95% CI: 88.2-1.7) for laBCC (complete response [CR]: 43/129; PR: 56/129) and mBCC (CR: 0/3; PR: 1/3), respectively. High-risk aBCC histopathological subtypes and occurrence of >2 therapy-related AEs were significantly associated with nonresponse to HHI therapy ([OR: 2.61; 95% CI: 1.09-6.05; p: 0.03] and [OR: 2.74; 95% CI: 1.03-7.9; p: 0.04]), respectively. Majority of our cohort (54.5%) developed at least 1 therapy-related AE, most of which were mild-moderate in severity.

CONCLUSIONS

Our results demonstrate the effectiveness and safety profile of HHI and confirm the reproducibility of pivotal trial results in real-life clinical setting.

Real-World Experience with Vismodegib on Advanced and Multiple BCCs: Data from the RELIVIS Study

BACKGROUND

Vismodegib is approved for advanced cases of basal cell carcinomas not amenable to surgery or radiotherapy. Large studies on the use of vismodegib in clinical practice are scarce.

OBJECTIVES

The main objective of the study was to analyse the evolution and therapeutic management of relapses and lack of response in patients who had received vismodegib for locally advanced and/or multiple basal cell carcinomas in a real-life multicentre setting.

METHODS

This nationwide retrospective study collected data on patients treated with vismodegib in 15 specialized centres. We included patients who first received vismodegib until intolerable toxicity, maximum response, or progressive disease. Exploratory research variables referred to patient and tumour characteristics, vismodegib effectiveness and safety, relapse rate and management, and mortality. A multivariable logistic regression model was used to identify predictors of complete clinical response.

RESULTS

133 patients with advanced BCC were included in the registry. The objective response rate (ORR) was 77.5% and nearly half of the patients (45.9%) achieved complete remission. Long-term information and detailed information of subsequent treatments after a regime of vismodegib was available for 115 patients. Only 34% of the patients in this group were subsequently treated with other therapies or vismodegib rechallenge. Sixty-nine percent of the patients who had shown a complete remission with vismodegib remained free of recurrence while 30.7% relapsed. Almost half of the patients who received additional therapies after the first course of vismodegib achieved complete tumour remission. Three and 2 out of 9 patients who were rechallenged with vismodegib achieved complete and partial responses, respectively, with an ORR of 55.5%.

CONCLUSION

Our study confirms efficacy of vismodegib in routine clinical practice. The risk of recurrence after achieving complete response with vismodegib was lower than previous reports. Rechallenge with vismodegib is feasible and most patients responded to re-treatment.

Retrospective Real-Life Data, Efficacy and Safety of Vismodegib Treatment in Patients with Advanced and Multiple Basal Cell Carcinoma: 3-Year Experience from a Spanish Center

BACKGROUND

Basal cell carcinoma (BCC) is the most common type of skin cancer and can represent a therapeutic challenge in patients with locally advanced disease. Vismodegib is a hedgehog pathway inhibitor approved by the FDA for use in this type of tumor. We present a case series to describe our experience with the use of vismodegib.

METHODS

A retrospective study that included patients treated with vismodegib at our dermatology unit was conducted. Monthly follow-up was performed, and we registered the clinical evolution and adverse reactions.

RESULTS

A total of six patients with locally advanced BCCs were included (50% males and 50% females), with a mean age of 78.5 years old. The treatment was administered over a mean of 5 months. A complete response was observed in four cases and partial response in two cases. No recurrence was detected, with a median follow-up duration after discontinuation of 18 months. Most patients (83%) had at least one adverse event, and two needed dose adjustment temporarily or permanently to continue. The main adverse effect was muscle spasms (66.7%). The main limitation of our study was the small sample, which was not representative of the general population.

CONCLUSIONS

Vismodegib is a safe and effective treatment for locally advanced BCC, and its role in unresectable BCC seems to be an important option in these challenging cases.

Pathogenesis of Oral Toxicities Associated with Targeted Therapy and Immunotherapy

Targeted therapy and immunotherapy have redefined cancer treatment. While they have enhanced tumor response and improved survival rates in many cancer types, toxicities continue to occur, and these often involve the oral cavity. Broadly reported as "mucositis" or "stomatitis," oral toxicities induced by targeted therapies differ clinically and mechanistically from those associated with conventional chemotherapy. Manifesting primarily as mucosal lesions, salivary gland hypofunction, or orofacial neuropathies, these oral toxicities may nonetheless lead to significant morbidity and impact patients' quality of life, thereby compromising clinical outcomes. We conclude that familiarity with the spectrum of associated toxicities and understanding of their pathogenesis represent important areas of clinical research and may lead to better characterization, prevention, and management of these adverse events.

Keratinocytic skin cancers-Update on the molecular biology

Although much attention has been devoted to a detailed genomic exposition of cutaneous melanoma, other nonmelanoma skin cancers have also recently been subjected to similar analytical scrutiny. Chief among these are the most common malignancies worldwide: basal cell carcinomas and cutaneous squamous cell carcinomas. In this review, the authors summarize their latest knowledge about the molecular pathways and therapeutic opportunities attendant to these keratinocytic skin cancers. PLAIN LANGUAGE SUMMARY: The most common cancers in the United States arise from skin cells called keratinocytes. Although these tumors are not formally tracked by the National Cancer Institute, it is estimated that there are millions of skin cancers called basal cell carcinomas and squamous cell carcinomas. This article reviews the current recent genetic insights into these tumors and therapeutic opportunities.

Management of Non-Melanoma Skin Cancer: Radiologists Challenging and Risk Assessment

Basal cell carcinoma, squamous cell carcinoma, and Merkel cell carcinoma are the three main types of nonmelanoma skin cancers and their rates of occurrence and mortality have been steadily rising over the past few decades. For radiologists, it is still difficult to treat patients with advanced nonmelanoma skin cancer. Nonmelanoma skin cancer patients would benefit greatly from an improved diagnostic imaging-based risk stratification and staging method that takes into account patient characteristics. The risk is especially elevated among those who previously received systemic treatment or phototherapy. Systemic treatments, including biologic therapies and methotrexate (MTX), are effective in managing immune-mediated diseases; however, they may increase susceptibility to NMSC due to immunosuppression or other factors. Risk stratification and staging tools are crucial in treatment planning and prognostic evaluation. PET/CT appears more sensitive and superior to CT and MRI for nodal and distant metastasis as well as in surveillance after surgery. The patient treatment response improved with advent and utilization of immunotherapy and different immune-specific criteria are established to standardized evaluation criteria of clinical trials but none of them have been utilized routinely with immunotherapy. The advent of immunotherapy has also arisen new critical issues for radiologists, such as atypical response pattern, pseudo-progression, as well as immune-related adverse events that require early identification to optimize and improve patient prognosis and management. It is important for radiologists to have knowledge of the radiologic features site of the tumor, clinical stage, histological subtype, and any high-risk features to assess immunotherapy treatment response and immune-related adverse events.

Efficacy and Safety of Sonic Hedgehog Inhibitors in Basal Cell Carcinomas: An Updated Systematic Review and Meta-analysis (2009-2022)

BACKGROUND

Basal cell carcinoma (BCC) of the skin is the most common form of skin cancer in the United States. In life-threatening, advanced BCC, sonic hedgehog inhibitors (SSHis) remain a pre-eminent treatment option for locally advanced BCC and metastatic BCC.

OBJECTIVE

In this updated systematic review and meta-analysis, we aimed to better characterize the efficacy and safety of SSHis by including final updates from pivotal clinical trials and additional new recent studies.

METHODS

An electronic database search was performed for articles including clinical trials, prospective case series, and retrospective medical record reviews on human subjects. Overall response rates (ORRs) and complete response rates (CRRs) were the primary outcomes. For safety assessment, the prevalence of the following adverse effects was analyzed: muscle spasms, dysgeusia, alopecia, weight loss, fatigue, nausea, myalgias, vomiting, skin squamous cell carcinoma, increased creatine kinase, diarrhea, decreased appetite, and amenorrhea. Analyses were performed using R statistical software. Data were pooled using linear models with fixed effects meta-analysis for primary analyses, along with 95% confidence intervals (CIs) and p-values. Intermolecular differences were calculated using Fisher's exact test.

RESULTS

A total of 22 studies (N = 2384 patients) were included in the meta-analysis: 19 studies assessing both efficacy and safety, 2 studies assessing safety only, and 1 study assessing efficacy only. Overall, the pooled ORR for all patients was 64.9% (95% CI 48.2-81.6%), implicating there is at least a partial response (z = 7.60, p < 0.0001) in most patients receiving SSHis. The ORR for vismodegib was 68.5% and 50.1% for sonidegib. The most common adverse effects for vismodegib and sonidegib were muscle spasms (70.5% and 61.0%, respectively), dysgeusia (58.4% and 48.6%, respectively), and alopecia (59.9% and 51.1%, respectively). Patients were likely to experience weight loss (35.1%, p < 0.0001) from vismodegib. Alternatively, patients taking sonidegib experienced more nausea, diarrhea, increased creatine kinase levels, and decreased appetite compared with those receiving vismodegib.

CONCLUSION

SSHis are an effective treatment for advanced BCC disease. Given the high discontinuation rates, management of patient expectations is warranted for compliance and achieving long-term efficacy. It is essential to stay updated with the latest discoveries on the efficacy and safety of SSHis.

The initial rate of tumour response to vismodegib treatment, can predict a complete response outcome for periocular LA-BCC

PURPOSE

To establish a model to predict treatment outcome of periocular locally advanced basal cell carcinoma (POLA BCC) based on initial response to treatment with vismodegib (ErivedgeTM), a sonic hedgehog inhibitor.

DESIGN

Subgroup analysis of data from the STEVIE study database.

METHODS

Analysis of medical history, treatment protocol, and treatment outcome of POLA BCC tumours in a STEVIE study population of 244 POLA BCC patients treated with ≥1 dose of vismodegib.

RESULTS

A predictive model for complete response (CR) was established based on the initial treatment response. A cutoff value of 20% reduction in tumour size at 3 months of treatment identified the patients with a high probability (82.76%) to achieve CR. A second cutoff value of 67.7% reduction in tumour size at 6 months of treatment improved the prediction to a 95.42% probability of a CR outcome.

CONCLUSIONS

A treatment model was constructed based on the prediction of a CR outcome and the initial response to vismodegib treatment at 3 and 6 months. The study result provide significant new insights can facilitate decision-making on treatment management according to tumour response in patients with POLA BCC.

The current clinical approach to difficult-to-treat basal cell carcinomas

INTRODUCTION

Basal cell carcinoma (BCC) is the most common malignant tumor in adult white populations. If BCCs are not treated for years, if they cause massive destruction of the surrounding tissues, if they are considered unresectable or not eligible for radiotherapy they become progressively 'locally advanced' (laBCC) or metastatic (mBCC). These tumors are defined as 'difficult-to-treat BCC.'

AREAS COVERED

A comprehensive search on PubMed was conducted to identify relevant literature about the several approved and recommended treatment options for the management of difficult-to-treat BCC published from January 2012 to July 2022. Surgical options, radiotherapy, hedgehog inhibitors, immunotherapy, and combined treatments are discussed. The keywords used were basal cell carcinoma; difficult-to-treat BCC; management of difficult-to-treat BCC; surgical therapy; radiotherapy; hedgehog inhibitors; immunotherapy.

EXPERT OPINION

Identifying the best approach to DTT BCCs is one of the main challenges for the dermato-oncologist. The introduction of HHI for the treatment of advanced BCCs has revolutionized the clinical management of DTT BCCs. The immune checkpoint inhibitor cemiplimab has been approved for the treatment of locally advanced or metastatic BCC refractory to HHI therapy or in patients intolerant to HHI therapy. Multidisciplinary teams (MDTs) play a key role in managing these complex patients.

Safety and efficacy of nivolumab, an anti-PD1 immunotherapy, in patients with advanced basal cell carcinoma, after failure or intolerance to sonic Hedgehog inhibitors: UNICANCER AcSé NIVOLUMAB trial

BACKGROUND

Basal cell carcinoma (BCC) is the most common human malignancy. In most cases, BCC has slow progression and can be definitively cured by surgery or radiotherapy. However, in rare cases, it can become locally advanced or, even more rarely, metastatic. The alternative recommended treatments are Sonic Hedgehog pathway inhibitors; however, the response is often short-lived.

METHODS

This was a phase 2 basket study (NCT03012581) evaluating the efficacy and safety of nivolumab in a cohort of 32 advanced BCC patients, enrolled after failure of Sonic Hedgehog inhibitors, including 29 laBCC (91%) and 3 mBCC (9%).

RESULTS

Compared to previously published studies, our population consisted of severe patients with a poor prognosis because they had already received multiple lines of treatment: all patients received previous Sonic Hedgehog inhibitors, 53% of patients already had chemotherapy and 75% radiotherapy. At 12 weeks, we reported 3.1% of complete responses, 18.8% of partial responses, and 43.8% of stable diseases. The best response rate to nivolumab reached 12.5% of complete responses (four patients), 18.8% of partial responses (three patients), and 43.8% of stable diseases (14 patients). Adverse events (AE) were mostly grade 2 or 3, slightly different to the adverse events observed in the treatment of metastatic melanoma (higher rate of diabetes, no thyroid dysfunction).

CONCLUSION

Nivolumab is a relevant therapeutic option for patients with advanced relapsing/refractory BCC.

[Current Management of Basal Cell Carcinoma]

AIM OF STUDY

We present the current standard in diagnosis and treatment of basal cell carcinoma. Useful procedures for clinical management should be derived from this.

METHODS

A systematic literature search was carried out in the PubMed online database. The collected information was analyzed and evaluated. An overall concept was created from the gained knowledge.

RESULTS

Basal cell carcinoma is the most common tumor in humans and its incidence is expected to increase in the future. When managing the disease, a one-dimensional orientation towards the clinical or histological subtype is not sufficient because of the heterogeneity of the tumor. The primary implementation of risk stratification, which is decisive for the further diagnostic and therapeutic steps, is becoming increasingly important. The gold standard in treatment continues to be the surgical procedure, which should be carried out using micrographically controlled surgery if possible. In addition, there are other therapeutic methods such as radiotherapy or a number of topical therapy options (photodynamic therapy, cryotherapy, application of 5-fluorouracil or imiquimod), which can be used in certain cases. Hedgehog inhibitors are also effective drugs for advanced or metastatic basal cell carcinoma. Practitioners have gained several years of experience with regard to effectiveness and handling of adverse events. With the PD-1 inhibitor cemiplimab, another therapeutic option for inoperable or metastatic tumors has been available since June 2021.

CONCLUSION

Basal cell carcinoma will continue to gain in relevance in daily dermatological practice in the coming years. A structured approach to the assessment of the existing risk category of the tumor and the subsequent determination of the optimal therapy regimen are of central importance. Advanced or metastatic tumors no longer represent a hopeless situation for the patient. With long-termhedgehog therapy, an adapted dosage scheme can avoid discontinuation of therapy due to side effects. The therapeutic potential of the PD-1 inhibitor cemiplimab can also be used with the side effect profile known from other types of skin cancer.

Cancer Metastasis and Treatment Resistance: Mechanistic Insights and Therapeutic Targeting of Cancer Stem Cells and the Tumor Microenvironment

Cancer metastasis and treatment resistance are the main causes of treatment failure and cancer-related deaths. Their underlying mechanisms remain to be fully elucidated and have been attributed to the presence of cancer stem cells (CSCs)-a small population of highly tumorigenic cancer cells with pluripotency and self-renewal properties, at the apex of a cellular hierarchy. CSCs drive metastasis and treatment resistance and are sustained by a dynamic tumor microenvironment (TME). Numerous pathways mediate communication between CSCs and/or the surrounding TME. These include a paracrine renin-angiotensin system and its convergent signaling pathways, the immune system, and other signaling pathways including the Notch, Wnt/β-catenin, and Sonic Hedgehog pathways. Appreciation of the mechanisms underlying metastasis and treatment resistance, and the pathways that regulate CSCs and the TME, is essential for developing a durable treatment for cancer. Pre-clinical and clinical studies exploring single-point modulation of the pathways regulating CSCs and the surrounding TME, have yielded partial and sometimes negative results. This may be explained by the presence of uninhibited alternative signaling pathways. An effective treatment of cancer may require a multi-target strategy with multi-step inhibition of signaling pathways that regulate CSCs and the TME, in lieu of the long-standing pursuit of a 'silver-bullet' single-target approach.

Nonsurgical treatment options for basal cell carcinoma

ABSTRACT

Basal cell carcinoma (BCC) is the most common form of nonmelanoma skin cancer. Surgery, including Mohs micrographic surgery, is considered the gold standard for the management of BCC, yet some patients may be unable to undergo surgery. This article describes effective nonsurgical options for treating superficial BCCs as well as some nodular and infiltrative BCCs.

Molecular Mechanisms and Targeted Therapies of Advanced Basal Cell Carcinoma

Among human cutaneous malignancies, basal cell carcinoma is the most common. Solid advances in unveiling the molecular mechanisms of basal cell carcinoma have emerged in recent years. In Gorlin syndrome, which shows basal cell carcinoma predisposition, identification of the patched 1 gene (PTCH1) mutation was a dramatic breakthrough in understanding the carcinogenesis of basal cell carcinoma. PTCH1 plays a role in the hedgehog pathway, and dysregulations of this pathway are known to be crucial for the carcinogenesis of many types of cancers including sporadic as well as hereditary basal cell carcinoma. In this review, we summarize the clinical features, pathological features and hedgehog pathway as applied in basal cell carcinoma. Other crucial molecules, such as p53 and melanocortin-1 receptor are also discussed. Due to recent advances, therapeutic strategies based on the precise molecular mechanisms of basal cell carcinoma are emerging. Target therapies and biomarkers are also discussed.

The Role of Surgery After Remission of Nonsystemic Extensive Periorbital Basal Cell Carcinoma Treated by Vismodegib: A Systematic Review

BACKGROUND

Eyelid basal cell carcinoma (BCC) is usually cured by surgery. However, for a minority of patients, extensive disease progression and recurrence contraindicate surgery or radiotherapy because of severe ocular morbidity. The hedgehog signaling pathway inhibitor vismodegib is becoming the key treatment for this specific form.

OBJECTIVE

The aim of this review was to define the role of surgery after vismodegib treatment.

MATERIALS AND METHODS

A literature search of the PubMed, Cochrane Library, ScienceDirect, and Embase databases was conducted for all articles published up to March 2021 to identify studies that examined treatment of BCC of the eyelid by vismodegib.

RESULTS

Level 1 evidence was found for the use of vismodegib as neoadjuvant therapy in locally advanced eyelid BCC contraindicated to surgery and/or radiotherapy with a rather good tolerance of treatment. Level 3 evidence was found for the role of surgical excision of residual clinically suspicious lesions as for the indication of eyelid reconstruction after mapping or during residual tumoral resection if frozen sections or Mohs surgery were performed.

CONCLUSION

Vismodegib is a well-tolerated treatment for advanced periorbital BCC. The hedgehog signaling pathway inhibitor vismodegib is a potential treatment option in patients with these challenging tumors.

Vismodegib in Locally Advanced Basal Cell Carcinoma in Slovenia

BACKGROUND

Vismodegib is a first-in-class inhibitor of the hedgehog pathway for treatment of locally advanced basal cell carcinoma (laBCC) and metastatic BCC.

OBJECTIVES

The purpose of this study is to report outcomes of patients with laBCC, with basal cell carcinoma nevus syndrome (Gorlin Goltz syndrome [G-G Syn]) treated with vismodegib in routine clinical practice in Slovenia in 8.3-year period.

METHODS

In this retrospective cohort study, we analyzed baseline characteristics, outcomes, and treatment-related adverse events from locally advanced BCC. The patients were divided into two cohorts: 39 laBCC or multiple BCC patients and 7 patients with G-G Syn who were treated with vismodegib from November 2012 till January 2021.

RESULTS

During 100-month period, 46 patients were diagnosed with laBCC (26), multiple BCC (13), and G-G Syn (7), all inappropriate for surgery or radiotherapy. Baseline characteristics: median age was 72.8 years in laBCC + multiple BCC cohort and 47.4 years in G-G Syn cohort. The objective response rate was 80% in laBCC + multiple BCC and 86% in G-G Syn cohort. Disease control rate (DCR) was 95% in laBCC + multiple BCC and 100% in G-G Syn cohort. Median duration of treatment was 9.9 months (range: 1.5-43.1) in laBCC and multiple BCC cohort and 19.5 months (range: 3.6-94.1) in G-G Syn cohort. Majority of treatment-emergent adverse events (TEAEs) in laBCC or multiple BCC cohort were grade 1 or 2 (96%), only 4% of AEs were grade 3. Majority of TEAEs in G-G Syn cohort were also grade 1 or 2 (87%), 13% of AEs were grade 3. No grade 4 or 5 vismodegib-related AEs were reported.

CONCLUSION

Vismodegib has shown meaningful efficacy with DCR from 95% to 100% in patients with laBCC, multiple BCC, and G-G Syn in Slovenia. TEAEs were successfully alleviated with multidisciplinary approach and early supportive care.

The overall process of metastasis: From initiation to a new tumor

Metastasis-a process that involves the migration of cells from the primary site to distant organs-is the leading cause of cancer-associated death. Improved technology and in-depth research on tumors have furthered our understanding of the various mechanisms involved in tumor metastasis. Metastasis is initiated by cancer cells of a specific phenotype, which migrate with the assistance of extracellular components and metastatic traits conferred via epigenetic regulation while modifying their behavior in response to the complex and dynamic human internal environment. In this review, we have summarized the general steps involved in tumor metastasis and their characteristics, incorporating recent studies and topical issues, including epithelial-mesenchymal transition, cancer stem cells, neutrophil extracellular traps, pre-metastatic niche, extracellular vesicles, and dormancy. Several feasible treatment directions have also been summarized. In addition, the correlation between cancer metastasis and lifestyle factors, such as obesity and circadian rhythm, has been illustrated.

Basal Cell Carcinoma: Pathology, Current Clinical Treatment, and Potential Use of Lipid Nanoparticles

Skin cancer is the most common type of carcinoma diagnosed worldwide, with significant morbidity and mortality rates among Caucasians, in particular basal cell carcinoma (BCC). The main risk factors of BCC are well-identified, and there are many chemotherapeutic drugs available for its treatment. The effectiveness of therapeutic options is governed by several factors, including the location of the tumor, its size, and the presence of metastases (although rare for BCC). However, available treatments are based on non-targeted approaches, which encounter a significant risk of systemic toxicity in several organs. Site-specific chemotherapy for BCC has been proposed via the loading of anticancer drugs into nanoparticles. Among various types of nanoparticles, in this review, we focus on potential new regimens for the treatment of BCC using classical anticancer drugs loaded into novel lipid nanoparticles. To meet patient aesthetic expectations and enhance the effectiveness of basal cell carcinoma treatment, new therapeutic topical strategies are discussed, despite a limited number of reports available in the literature.

Characteristics of the cancer stem cell niche and therapeutic strategies

Distinct regions harboring cancer stem cells (CSCs) have been identified within the microenvironment of various tumors, and as in the case of their healthy counterparts, these anatomical regions are termed “niche.” Thus far, a large volume of studies have shown that CSC niches take part in the maintenance, regulation of renewal, differentiation and plasticity of CSCs. In this review, we summarize and discuss the latest findings regarding CSC niche morphology, physical terrain, main signaling pathways and interactions within them. The cellular and molecular components of CSCs also involve genetic and epigenetic modulations that mediate and support their maintenance, ultimately leading to cancer progression. It suggests that the crosstalk between CSCs and their niche plays an important role regarding therapy resistance and recurrence. In addition, we updated diverse therapeutic strategies in different cancers in basic research and clinical trials in this review. Understanding the complex heterogeneity of CSC niches is a necessary pre-requisite for designing superior therapeutic strategies to target CSC-specific factors and/or components of the CSC niche.

Advanced basal cell carcinoma: What dermatologists need to know about treatment

The treatment of advanced basal cell carcinoma (BCC) often requires therapies beyond local surgical excision or radiation due to the invasiveness of the tumor. Historically, cytotoxic chemotherapy was used to treat advanced BCC, but with limited data, no standard regimens were established. The discovery of cyclopamine, a natural inhibitor in the Hedgehog pathway, led to the development of the 2 currently approved Hedgehog inhibitors, vismodegib and sonidegib. Both agents are indicated for locally advanced BCC, while vismodegib is also indicated for metastatic BCC. In patients who progress on hedgehog inhibitors or cannot tolerate hedgehog inhibitors, the programmed cell death protein 1 inhibitor cemiplimab can be used to treat locally advanced or metastatic disease. Complex cases of locally advanced or metastatic BCC may be best discussed through a multidisciplinary approach in order to determine the optimal treatment approach for the individual patient.

Metastatic insidious super giant basal cell carcinoma

A middle-aged woman presented with a mechanical fall. Physical examination revealed a massive purulent ulcerated lesion spanning her entire back and axilla, which had reportedly been brewing for over a decade. Punch biopsy revealed infiltrative basal cell carcinoma. She was treated with Vismodegib, with a remarkable decrease in the size of the cancer. However, surveillance imaging after 6 months of treatment revealed new bone metastases. In the setting of progressive disease, medical therapy was switched to cemiplimab instead. Basal cell carcinoma is commonly known as a benign tumour of the skin, rarely larger than 5 cm. Here, we discuss the entity of metastatic super giant basal cell carcinoma; this case is one of the largest reported lesions. As locoregional therapy, such as surgery is sometimes not appropriate for such advanced lesions, we discuss the current forefront of therapy including oral hedgehog pathway and check point inhibitors.

Real-World Treatment Patterns and Outcomes Among Patients with Basal Cell Carcinoma Following First-Line Hedgehog Inhibitor Discontinuation

INTRODUCTION

Until recently, patients discontinuing first-line (1L) hedgehog inhibitors (HHIs) for basal cell carcinoma (BCC) had few subsequent treatment options. The objective of this study was to describe the treatment journey and prognosis of patients discontinuing 1L HHI for BCC.

METHODS

This was a retrospective cohort study of patients with BCC who discontinued 1L HHI treatment in The US Oncology Network between 1 January 2012 and 1 January 2019 (with follow-up until 1 May 2020). Two cohorts were identified: patients who initiated a second-line (2L) treatment (2L initiators), and patients with 1L progression or toxicity without pathology-confirmed complete response who did not initiate 2L treatment (2L non-initiators). Patient demographics, treatment characteristics, and outcomes are reported for each cohort.

RESULTS

Among 115 patients with BCC who received 1L HHI treatment, 63.5% (n = 73/115) discontinued 1L HHIs. Of those, 50.7% (n = 37/73) discontinued because of documented toxicity or progression, without evidence of a complete response. We identified 4 patients who initiated 2L systemic treatment (median age 68.7 years, 100.0% female) and 15 patients who were eligible for the 2L non-initiator cohort (median age 80.2 years, 20.0% female). Median 1L HHI duration was 6.8 months (range 1.9-20.6 months) for the 2L non-initiator cohort and 8.6 months (range 6.8-42.2 months) for 2L initiators. At the end of follow-up, among 2L non-initiators (median follow-up duration 9.7 months), 40.0% were lost to follow-up, 33.3% had died, 20.0% continued observation, and 6.7% transitioned to an academic medical center or hospital; among 2L initiators (median follow-up duration 6.3 months), 50.0% were lost to follow-up, 25.0% had died, and 25.0% continued observation.

CONCLUSIONS

Following 1L HHI discontinuation, lack of standardized care and suboptimal outcomes were observed, including limited receipt of 2L treatment. Further studies are necessary to evaluate the impact of newer BCC treatment options.

Clinical activity of PD-1 inhibition in the treatment of locally advanced or metastatic basal cell carcinoma

Background

Basal cell carcinoma (BCC) is the most common malignancy worldwide, yet the management of patients with advanced or metastatic disease is challenging, with limited treatment options. Recently, programmed death receptor 1 (PD-1) inhibition has demonstrated activity in BCC after prior Hedgehog inhibitor treatment.

Methods

We conducted a multicenter, retrospective analysis of BCC patients treated with PD-1 inhibitor therapy. We examined the efficacy and safety of PD-1 therapy, as well as clinical and pathological variables in association with outcomes. Progression-free survival (PFS), overall survival (OS) and duration of response (DOR) were calculated using Kaplan-Meier methodology. Toxicity was graded per Common Terminology Criteria for Adverse Events V.5.0.

Results

A total of 29 patients with BCC who were treated with PD-1 inhibition were included for analysis, including 20 (69.0%) with locally advanced and 9 (31.0%) with metastatic disease. The objective response rate was 31.0%, with five partial responses (17.2%), and four complete responses (13.8%). Nine patients had stable disease (31.0%), with a disease control rate of 62.1%. The median DOR was not reached. Median PFS was 12.2 months (95% CI 0.0 to 27.4). Median OS was 32.4 months (95% CI 18.1 to 46.7). Two patients (6.9%) developed grade 3 or higher toxicity, while four patients (13.8%) discontinued PD-1 inhibition because of toxicity. Higher platelets (p=0.022) and any grade toxicity (p=0.024) were significantly associated with disease control rate.

Conclusions

The clinical efficacy of PD-1 inhibition among patients with advanced or metastatic BCC in this real-world cohort were comparable to published trial data. Further investigation of PD-1 inhibition is needed to define its optimal role for patients with this disease.