Safety and efficacy of vismodegib in patients with basal cell carcinoma nevus syndrome: pooled analysis of two trials

Assessment of Mammalian Target of Rapamycin Pathway Activation in Basal Cell Carcinoma as a New Therapeutic Approach

ABSTRACT

Targeting the mammalian target of rapamycin (mTOR) pathway represents a potentially novel approach to treat basal cell carcinoma (BCC), but activation of this pathway has not been well described in human BCCs. The purpose of this study was to assess whether mTOR pathway activation occurs in BCCs (both sporadic and syndromic) and report a case of a patient with Gorlin syndrome (GS) whose clinically suspicious BCCs responded to mTOR inhibition through topical sirolimus treatment. After Stanford Institutional Review Board Approval, archived BCCs from patients with GS (n = 25), sporadic BCCs (n = 35), and control tissues were subjected to immunohistochemical analysis for the activation of mTOR pathway, and immunohistochemical staining intensity was evaluated by a dermatopathologist. BCCs (compared with normal skin) had elevated levels of eIF4EBP1 ( Padjusted = 0.0336), which is downstream of mTOR. a serine/threonine kinase Phospho-(AKT), which interacts with mTOR, was also significantly elevated (perinuclear: Padjusted < 0.0001; cytoplasmic: Padjusted = 0.0021). When off-label topical 1% sirolimus was used on a pediatric patient with GS, we noted reduction of new BCC development and decreased size of existing neoplasms clinically suspicious for BCCs. This treatment was well tolerated after 2 years of continuous use, with no other treatments needed during this period. Topical sirolimus is a promising therapeutic candidate against both sporadic and GS-associated BCC. Multicenter, prospective studies are needed to understand the efficacy and safety of topical mTOR inhibitors in BCC treatment, and ascertain whether the immunohistochemical markers downstream of mTOR could have predictive value in identifying BCCs most likely to respond to topical mTOR inhibitors, such as sirolimus.

Towards Precision Oncology: The Role of Smoothened and Its Variants in Cancer

The G protein-coupled receptor Smoothened (Smo) is a central signal transducer of the Hedgehog (Hh) pathway which has been linked to diverse forms of tumours. Stimulated by advancements in structural and functional characterisation, the Smo receptor has been recognised as an important therapeutic target in Hh-driven cancers, and several Smo inhibitors have now been approved for cancer therapy. This receptor is also known to be an oncoprotein itself and its gain-of-function variants have been associated with skin, brain, and liver cancers. According to the COSMIC database, oncogenic mutations of Smo have been identified in various other tumours, although their oncogenic effect remains unknown in these tissues. Drug resistance is a common challenge in cancer therapies targeting Smo, and data analysis shows that healthy individuals also harbour resistance mutations. Based on the importance of Smo in cancer progression and the high incidence of resistance towards Smo inhibitors, this review suggests that detection of Smo variants through tumour profiling could lead to increased precision and improved outcomes of anti-cancer treatments.

A case of nevoid basal cell carcinoma syndrome dominated by facial basal cell carcinoma

Nevus-like basal cell carcinoma syndrome (NBCCS) is a rare autosomal dominant disease characterized by the occurrence of multiple maxillofacial keratocysts, basal cell carcinoma, child medulloblastoma, and various skeletal and soft tissue dysplasia. In 2020, a patient with NBCCS dominated by facial basal cell carcinoma was admitted to Xiangya Hospital of Central South University. The patient was an elderly woman. Ten years ago, the systemic mass appeared, especially on the face, but it was not treated. Later, these masses gradually increased in volume and number, and showed invasive properties. The nasal mass was broken and suppurated, seriously affecting the patient's life quality. The patient came to the hospital to improve the symptoms. Staphylococcus aureus and Providencia rettgeri were cultured in the patient's nasal secretions. Nasal sinus enhanced MRI showed that the subcutaneous soft tissue of the right cheek and the anterolateral mucosa of the left nasal cavity were invaded, indicating multiple malignant skin lesions. After admission, local anesthesia was performed and some masses were removed. Pathological examination of the mass showed basal cell carcinoma. After general anesthesia, multiple masses were resected. The postoperative pathological examination showed that multiple basal cell carcinoma invaded the deep dermis near subcutaneous fat layer. Combined with the results of clinical and immunohistochemical examination, the patient was diagnosed as NBCCS. There were no clear tumor thrombus in the vessel and no nerve invasion. No recurrence or new tumor was found after 1 year follow-up. The incidence rate of NBCCS is low and clinical symptoms are different. The patient's life quality is poor and the patient needs long-term individualized treatment.

Real-World Experience of Vismodegib in Advanced Basal Cell Carcinoma at a Canadian Cancer Center

BACKGROUND

Vismodegib is a novel Hedgehog pathway inhibitor that has revolutionized the treatment of patients with advanced basal cell carcinoma (BCC) who are poor candidates for surgery or radiation. Few studies have explored the use of vismodegib to facilitate further surgery or radiotherapy, and the optimal treatment duration to balance outcomes with adverse effects.

OBJECTIVES

To characterize the disease response, progression, and recurrence outcomes of BCC patients, and to report the impact of subsequent therapies.

METHODS

We performed a retrospective study of 46 adult patients with advanced basal cell carcinoma (aBCC), including both locally advanced (laBCC) and metastatic (mBCC) disease, treated with vismodegib at a single center from 2012 to 2019.

RESULTS

Thirty-six had laBCC, and 10 had mBCC. Treatment was given over a mean of 21.9 months. Twenty-three (50%) had a complete response (CR), and 19 (41.3%) achieved partial response (PR). Median time to maximal response was 5.3 months. Eleven (23.9%) had resected disease at median 17.2 months, and 11 patients (23.9%) received radiotherapy. Thirty-two (69.6%) experienced progressive disease after achievement of CR or PR. Among 17 CR patients, who stopped treatment, 14 (82.3%) experienced subsequent relapse; 6 (85%) attained a repeat response. Twenty (43.5%) discontinued treatment at least once due to adverse effects.

CONCLUSIONS

With a response rate of 91%, London Regional Cancer Center's (LRCP)'s experience with vismodegib supports its effectiveness in treatment of aBCC. Moreover, a significant number of patients treated with vismodegib became amenable to surgery or radiotherapy. Toxicity remained an important factor that limited treatment duration.

Predictive Factors of Non-Response to Vismodegib in Locally Advanced Basal-Cell Carcinoma

BACKGROUND

Vismodegib has shown clinical efficacy in the management of locally advanced basal cell carcinomas (laBCC). However, non-response to vismodegib is observed in 2-13.5% of patients in clinical studies. The purpose of this study was to identify factors associated with non-response to vismodegib in patients with laBCC.

METHODS

We carried out a retrospective multicenter study, including patients with laBCC treated with vismodegib, from July 2011 to May 2019. Response to treatment was assessed according to the RECIST 1.1 criteria. Patients were categorized as responders with a complete response or a partial response or non-responders with a stable disease or a progressive disease according to what has been observed during follow-up. Patient demographics, tumor profile, and treatment modalities were compared in responders and non-responders.

RESULTS

Eighty-three patients with laBCC were included in the study. Twenty-five (30.1%) were non-responders to vismodegib. History of treatment with radiotherapy, presence of muscle involvement and intermittent treatment with vismodegib were significantly associated with a non-response (p < 0.001, p = 0.025, p < 0.001). Bone involvement (p = 0.2) and morpheaform IaBCC subtype (p = 0.056) were more frequent in non-responders without reaching statistical significance.

CONCLUSION

In this study, non-response of laBCC to vismodegib therapy was associated with muscle involvement. Previous radiotherapy and intermittent use of vismodegib have been identified as causes favoring non-response to vismodegib. Due to the low numbers of patients included in the study, it is difficult to draw firm conclusions. Further studies are needed to confirm these data.

Drug holiday approach for Vismodegib treatment in patients with nevoid basal cell carcinoma syndrome: Three cases from real clinical practice

Sonic hedgehog pathway inhibitor Vismodegib is the first systemic treatment to be approved for metastatic or locally advanced basal cell carcinoma non-subsidiary of surgical treatment, and appears to be a promising treatment option for patients with nevoid basal cell carcinoma syndrome. In these patients, where repeated or prolonged treatment may be necessary, the psychological exhaustion caused by the chronicity of less severe adverse effects appears as the main limiting factor in the persistence of the drug in the long term and in the willingness of patients to take the drug again after its suspension. We report our experience with three cases where a drug holiday approach was effective in decreasing the intensity of adverse effects or improving the patient's subjective tolerance to the drug while maintaining clinical response.

Triple-Negative Breast Cancer: A Review of Conventional and Advanced Therapeutic Strategies

Triple-negative breast cancer (TNBC) cells are deficient in estrogen, progesterone and ERBB2 receptor expression, presenting a particularly challenging therapeutic target due to their highly invasive nature and relatively low response to therapeutics. There is an absence of specific treatment strategies for this tumor subgroup, and hence TNBC is managed with conventional therapeutics, often leading to systemic relapse. In terms of histology and transcription profile these cancers have similarities to BRCA-1-linked breast cancers, and it is hypothesized that BRCA1 pathway is non-functional in this type of breast cancer. In this review article, we discuss the different receptors expressed by TNBC as well as the diversity of different signaling pathways targeted by TNBC therapeutics, for example, Notch, Hedgehog, Wnt/b-Catenin as well as TGF-beta signaling pathways. Additionally, many epidermal growth factor receptor (EGFR), poly (ADP-ribose) polymerase (PARP) and mammalian target of rapamycin (mTOR) inhibitors effectively inhibit the TNBCs, but they face challenges of either resistance to drugs or relapse. The resistance of TNBC to conventional therapeutic agents has helped in the advancement of advanced TNBC therapeutic approaches including hyperthermia, photodynamic therapy, as well as nanomedicine-based targeted therapeutics of drugs, miRNA, siRNA, and aptamers, which will also be discussed. Artificial intelligence is another tool that is presented to enhance the diagnosis of TNBC.

The Role of Dermal Fibroblasts in Nevoid Basal Cell Carcinoma Syndrome Patients: An Overview

Nevoid basal cell carcinoma syndrome (NBCCS), also named Gorlin syndrome, is a rare multisystem genetic disorder characterized by marked predisposition to basal cell carcinomas (BCCs), childhood medulloblastomas, maxillary keratocysts, celebral calcifications, in addition to various skeletal and soft tissue developmental abnormalities. Mutations in the tumor suppressor gene PATCHED1 (PTCH1) have been found to be associated in the majority of NBCCS cases. PATCH1 somatic mutations and loss of heterozygosity are also very frequent in sporadic BCCs. Unlike non-syndromic patients, NBCCS patients develop multiple BCCs in sun-protected skin area starting from early adulthood. Recent studies suggest that dermo/epidermal interaction could be implicated in BCC predisposition. According to this idea, NBCCS fibroblasts, sharing with keratinocytes the same PTCH1 germline mutation and consequent constitutive activation of the Hh pathway, display features of carcinoma-associated fibroblasts (CAF). This phenotypic traits include the overexpression of growth factors, specific microRNAs profile, modification of extracellular matrix and basement membrane composition, increased cytokines and pro-angiogenic factors secretion, and a complex alteration of the Wnt/-catenin pathway. Here, we review studies about the involvement of dermal fibroblasts in BCC predisposition of Gorlin syndrome patients. Further, we matched the emerged NBCCS fibroblast profile to those of CAF to compare the impact of cell autonomous "pre-activated state" due to PTCH1 mutations to those of skin tumor stroma.

What's New in Genetic Skin Diseases

The discoveries of new genes underlying genetic skin diseases have occurred at a rapid pace, supported by advances in DNA sequencing technologies. These discoveries have translated to an improved understanding of disease mechanisms at a molecular level and identified new therapeutic options based on molecular targets. This article highlights just a few of these recent discoveries for a diverse group of skin diseases, including tuberous sclerosis complex, ichthyoses, overgrowth syndromes, interferonopathies, and basal cell nevus syndrome, and how this has translated into novel targeted therapies and improved patient care.

Vismodegib: A Review in Advanced Basal Cell Carcinoma

Vismodegib (Erivedge^®) is the first-in-class, oral small molecule inhibitor of the Hedgehog (Hh) pathway, abnormal activation of which is associated with basal cell carcinoma (BCC). In the USA, vismodegib is indicated for the treatment of adults with metastatic BCC (mBCC) or with locally-advanced BCC (LaBCC) that has recurred following surgery or who are not candidates for surgery, and who are not candidates for radiation. Similarly, in the EU, vismodegib is indicated for the treatment of adult patients with symptomatic mBCC, or with laBCC inappropriate for surgery or radiotherapy. The full European approval of vismodegib was based on the results of two phase II, open-label, noncomparative, international trials (ERIVANCE BCC and STEVIE), both of which showed high rates of tumour control in the indicated patient populations, including individuals with or without Gorlin syndrome. These studies also showed that vismodegib has an acceptable and manageable tolerability profile characterized by a number of class-related treatment-emergent adverse events, including muscle spasms, taste disturbances, alopecia, weight loss and asthenia (fatigue). Primary and secondary resistance to vismodegib has been documented, albeit at a low rate compared with some other targeted therapies. Vismodegib is therefore an effective and generally well tolerated systemic therapy for patients with mBCC and laBCC that can no longer be suitably controlled with surgery and/or radiotherapy. Historically, it is the first member of a class of drugs (Hh pathway inhibitors) that are now considered to be first-line treatment options for such individuals.

Mutations in SUFU and PTCH1 genes may cause different cutaneous cancer predisposition syndromes: similar, but not the same

Many cancer predisposition syndromes are preceded or accompanied by a range of typical skin signs. Gorlin syndrome is a rare multisystem inherited disorder which can predispose to basal cell carcinomas (BCCs), childhood medulloblastomas in addition to various developmental abnormalities; the majority of cases are due to mutations in the PTCH1 gene. Approximately 5% of cases have been attributed to a mutation in the SUFU gene. Certain phenotypic features have been identified as being more prevalent in individuals with a SUFU mutation such as childhood medulloblastoma, infundibulocystic BCCs and trichoepitheliomas. Recently hamartomatous skin lesions have also been noted in families with childhood medulloblastoma, a "Gorlin like" phenotype and a SUFU mutation. Here we describe a family previously diagnosed with Gorlin syndrome with a novel SUFU splice site deleterious genetic variant, who have several dermatological features including palmar sclerotic fibromas which has not been described in relation to a SUFU mutation before. We highlight the features more prominent in individuals with a SUFU mutation. It is important to note that emerging therapies for treatment of BCCs in patients with a PTCH1 mutation may not be effective in those with a SUFU mutation.

Oral Hedgehog Pathway Inhibition as a Means for Ocular Salvage in Locally Advanced Intraorbital Basal Cell Carcinoma

BACKGROUND

Basal cell cancer is the most common cutaneous malignancy. It rarely presents with locally advanced or metastatic disease. Rare presentations such as intraorbital invasion remain a difficult clinical problem with significant potential morbidity. There is no review of sonic hedgehog pathway inhibitors (HPIs) for intraorbital basal cell cancer, and evidence regarding optimal management is limited.

OBJECTIVE

To evaluate the evidence for the management of intraorbital basal cell cancer with HPIs.

METHODS

A search to identify evidence for treatment intraorbital basal cell cancers with HPIs to date was performed in PubMed database and OVID using the phrases "basal cell cancer/carcinoma/BCC," "intraorbital," "orbital," "ocular," "periocular," "vismodegib," "GDC-0449," "sonidegib," and "LDE224," in various combinations with Boolean operators "AND" and "OR."

RESULTS

Rigorous clinical trials have previously reported the use of vismodegib and sonidegib in locally advanced and metastatic basal cell carcinoma (BCC). However, specific descriptions of treatment of intraorbital tumors are rarely presented in detail adequate for analysis. Twenty-two cases of intraorbital BCC treated with vismodegib have been described in the literature, and no cases using sonidegib were identified. These vary in quality, but highlight important questions regarding optimal treatment duration, follow-up, and adjunctive therapies. Reports describing locally advanced BCC in various facial and periocular locations, but without specific mention of intraorbital invasion, were excluded.

CONCLUSION

Vismodegib is an attractive eye and vision-sparing option in patients with locally advanced intraorbital basal cell cancer whose other options often include exenteration, radiation, or other radical surgery.

Stem cell fate in cancer growth, progression and therapy resistance

Although we have come a long way in our understanding of the signals that drive cancer growth, and how these signals can be targeted, effective control of this disease remains a key scientific and medical challenge. The therapy resistance and relapse that are commonly seen are driven in large part by the inherent heterogeneity within cancers that allows drugs to effectively eliminate some, but not all, malignant cells. Here, we focus on the fundamental drivers of this heterogeneity by examining emerging evidence that shows that these traits are often controlled by the disruption of normal cell fate and aberrant adoption of stem cell signals. We discuss how undifferentiated cells are preferentially primed for transformation and often serve as the cell of origin for cancers. We also consider evidence showing that activation of stem cell programmes in cancers can lead to progression, therapy resistance and metastatic growth and that targeting these attributes may enable better control over a difficult disease.

Small Molecule Inhibitors of the Hedgehog Pathway in the Treatment of Basal Cell Carcinoma of the Skin

Basal cell carcinoma (BCC) is the most common type of skin cancer, with rising incidence rates primarily attributed to an aging population and ultraviolet radiation exposure. While the majority of BCCs are localized and respond to standard therapies, a very small minority of these tumors become locally destructive or metastasize. These advanced BCCs may not be amenable to localized treatment with surgery and/or radiation therapy. Most BCCs result from mutations in key receptors in the Hedgehog (HH) signaling pathway. As a result, identification of drugs that inhibit the receptor Smoothened (SMO) in the HH pathway has resulted in novel therapeutic approaches to treating patients with advanced BCC. These HH-pathway inhibiting medications have shown efficacy in clinical trials, and two medications, vismodegib and sonidegib, have received FDA approval. However, several limitations of these drugs have been identified, including treatment-limiting adverse events, drug resistance, and the formation of additional malignancies. This paper aims to summarize the clinical trials leading to the approval of SMO inhibitors, as well as reviewing potential mechanisms driving tumor resistance and the formation of cutaneous squamous cell carcinomas. Strategies to overcome some of these challenges, including the development of drugs that inhibit other downstream targets in the HH pathway, are the subject of ongoing clinical trials.

Gorlin Syndrome

Gorlin syndrome is a rare autosomal dominant disease caused by mutations in the sonic hedgehog signaling pathway. Of particular importance is the PTCH1 gene. The disease is characterized by the development of multiple basal cell carcinomas at young ages. These tumors may present with other skin manifestations such as palmoplantar pits and with extracutaneous manifestations such as odontogenic keratocysts and medulloblastoma. Although the dermatologist may be key for recognizing clinical suspicion of the syndrome, a multidisciplinary team is usually necessary for diagnosis, treatment, and follow-up. Skin treatment may be complicated due to the large number of basal cell carcinomas and the extent of involvement. In recent years, new drugs that inhibit targets in the sonic hedgehog pathway have been developed. Although these agents appear promising options for patients with Gorlin syndrome, their efficacy is limited by adverse effects and the development of resistance.

Challenges and Recent Advances in Medulloblastoma Therapy

Medulloblastoma (MB) is the most common childhood brain tumor, which occurs in the posterior fossa. MB tumors are highly heterogeneous and have diverse genetic make-ups, with differential microRNA (miRNA) expression profiles and variable prognoses. MB can be classified into four subgroups, each with different origins, pathogenesis, and potential therapeutic targets. miRNA and small-molecule targeted therapies have emerged as a potential new therapeutic paradigm in MB treatment. However, the development of chemoresistance due to surviving cancer stem cells and dysregulation of miRNAs remains a challenge. Combination therapies using multiple drugs and miRNAs could be effective approaches. In this review we discuss various MB subtypes, barriers, and novel therapeutic options which may be less toxic than current standard treatments.

Scalping Surgery - Dermatologic Indications beyond Curative Primary Skin Cancer Surgery

Skin tumours are among the most frequent tumour types of mankind. In the case of large tumours, field cancerization, or satellitosis scalping surgery is a possible option. The procedure can also be used in a palliative setting with tumour debulking. Less common indications are multiple benign tumours of the scalp and chronic inflammatory scalp dermatoses not responding to medical treatment. We present a case series and discuss surgical modalities beyond curative surgery of primary skin cancer.

Spotlight on vismodegib in the treatment of basal cell carcinoma: an evidence-based review of its place in therapy

Vismodegib is approved for the treatment of adult patients with metastatic (mBCC) or locally advanced basal cell carcinoma (laBCC) that have recurred following surgery or for those who are not good candidates for surgery (risk/benefit ratio is against patient's benefit, either because of the general condition or because of the expected morbidity from the surgery) or radiation therapy. This article provides an evidence-based review of its current place in therapy. Analytically, the clinical implications in the management of laBCCs and mBCCs and possible new indications, including the neoadjuvant use before surgical excision, are discussed, while in the end, the challenges regarding class-related adverse events and their optimal management are highlighted.