Markedly improved overall survival in 10 consecutive patients with metastatic basal cell carcinoma

Qualitative Patient Interviews to Characterize the Human Burden of Advanced Basal Cell Carcinoma Following Hedgehog Pathway Inhibitor Treatment

INTRODUCTION

Evidence of patients' experiences of living with advanced basal cell carcinoma (aBCC) are limited, particularly after hedgehog pathway inhibitor (HHI) treatment. We explored the burden of aBCC on symptoms and patients' everyday lives post HHI treatment.

METHODS

In-depth, semi-structured, approximately 1-h qualitative interviews of US patients with aBCC and prior HHI treatment were conducted. Data were assessed using thematic analysis with NVivo 1.0 software. Saturation analysis was performed to ensure all concepts were captured.

RESULTS

Fifteen patients (median age, 63 years; locally advanced BCC, n = 9; metastatic BCC, n = 6) were interviewed. A patient-led conceptual model was developed from the responses using 10 symptoms and 15 impact categories (comprising emotional/psychological, physical, and social domains) identified as most commonly discussed and important to patients. Overall, reported impacts were discussed more commonly than reported symptoms. Impacts most commonly discussed were related to emotions (e.g., anxiety, worry, fear [n = 14; 93%]; low mood, depression [n = 12; 80%]) and physical function (e.g., hobbies or leisure activities [n = 13; 87%]). Symptoms most commonly discussed were fatigue and tiredness (n = 14; 93%) and itch (n = 13; 87%). Out of all reported impacts and symptoms, fatigue and tiredness (n = 7, 47%) and anxiety, worry, and fear (n = 6; 40%) were most bothersome to patients. As a descriptive exercise, participant responses were mapped to commonly used patient-reported outcome scales in aBCC clinical trials. Most expressed concepts were captured across two common measures in oncology/skin conditions (European Organization for Research and Treatment of Cancer Quality of Life-Core 30 [EORTC QLQ-C30] and Skindex-16 questionnaires), but sun avoidance and others' perception of skin cancer were not explicitly mentioned by these instruments.

CONCLUSION

Patients with aBCC experienced a significant disease burden post first-line HHI therapy, including major emotional and lifestyle impacts. Accordingly, through this study, patients with aBCC highlighted a significant unmet need for second-line treatment options post HHI therapy.

Clinical and Histopathologic Characteristics of Metastatic and Locally Advanced Cutaneous Basal Cell Carcinomas

ABSTRACT

Locally advanced or metastatic basal cell carcinomas (laBCCs or mBCCs) are rare, with few case series providing information on their epidemiology. We aimed to describe the clinical and histologic features of locally advanced and metastatic basal cell carcinomas. Forty cases of laBCC or mBCC were identified by searching Vanderbilt's database from 1984 to January 2019. A retrospective chart review was performed. Pathology slides were available for 23 cases (13 mBCCs and 10 laBCCs). Twenty-one of 23 cases were Clark level IV or V, with a mean depth of invasion of >7 mm for both types. The mean mitotic rate was 4.4 mitoses/mm2 for laBCCs and 3.3 mitoses/mm2 for mBCCs. Ulceration was identified in 7 laBCC and 8 mBCC cases. Perineural invasion was present in 2 laBCC and 6 mBCC cases, with 3 mBCCs invading nerves >0.1 mm. Of 13 mBCC cases, histologic subtypes included infiltrative (n = 9), nodular (n = 7), morpheaform (n = 4), and superficial (n = 2), with multiple patterns present in some specimens. 10 of 13 patients with mBCC had local recurrence before metastasis. In summary, we identified several potential markers of high-risk BCC, including perineural invasion, deep invasion, elevated mitotic rate, and local recurrence of the primary tumor.

Metastasizing basal cell carcinoma: A clinicopathologic and immunohistochemical study of 22 cases

Basal cell carcinomas metastasize rarely, and there have been limited studies of potential drivers for this metastasis. Epithelial-mesenchymal transition (EMT) may play a role, although this has not been investigated in detail. We reviewed clinicopathologic features of 22 patients with metastasizing basal cell carcinoma (MBCC). Immunohistochemical markers of EMT, including CD44, E-cadherin, claudin, smooth muscle actin, beta-catenin, Twist1, and Oct 3/4, were evaluated on 10 MBCC (primary and metastases) and 18 non-metastasizing BCC. Primary sites included the head and neck, trunk, and extremity, while metastatic sites included lymph nodes, lung, bone, and soft tissue. Of 19 cases with follow-up, the range of follow-up after diagnosis of metastasis was 5 to 248 months (median: 50 months). Two cases were of unknown primary, nine metastases were diagnosed concurrently with primary tumors, and remaining cases showed a median latency between diagnosis of primary and metastatic tumors of 27.5 months (range: 3-81 months). Median survival was 66 months. Compared to non-metastasizing BCC, MBCC demonstrated reduced CD44 expression (primary [P = .0036], metastatic [P = .011]) and increased Twist1 expression (primary, P = .0017). MBCC shows variably aggressive behavior, and reduced CD44 and increased Twist1 expression may indicate significant EMT in metastasizing tumors and signify a metastatic phenotype.

Metastatic Basal Cell Carcinoma of the Skin: A Comprehensive Literature Review, Including Advances in Molecular Therapeutics

Basal cell carcinoma (BCC) of the skin is the most common type of malignant human tumor. In Europe, the incidence of BCC ranges from 44.6 to 128 cases per 100,000 inhabitants annually, whereas in the United States, the yearly incidence rate ranges between 500 and 1500. The global incidence has been calculated to be as high as 10 million cases of BCC per year. There are 2 main clinical patterns of BCC-the familial BCC in basal cell nevus syndrome and sporadic BCC. The etiology of cutaneous BCC is usually the result of the interaction between solar ultraviolet radiation and genetic factors. Somatic or germline mutations in the effector components of the hedgehog signaling pathway (ie, PTCH1, PTCH2, SMO or SUFU genes) are responsible for ∼90% of the cases of both sporadic and familial BCC, all causing a constitutive activation of the hedgehog pathway. Cutaneous BCC very rarely metastasizes, and diagnosis in metastatic sites can be very difficult. Metastatic BCC has weakly effective therapeutic options with a poor prognosis until few years ago. In 2012, small-molecule therapies, involving inactivation of the hedgehog signaling pathway, and capable of reducing tumor growth and progression have been introduced into clinical practice for advanced (locally advanced or metastatic) BCC. We performed a comprehensive literature review on metastatic BCC and found at least 915 cases reported to date. In addition, we extensively discussed the differential diagnosis of metastatic BCC, and outlined the advances in clinical therapeutics involving these small molecules.

Metastatic Cutaneous Basal Cell Carcinoma: Report of 2 Cases Preceding the Hedgehog Pathway Antagonists Era

Basal cell carcinoma (BCC) of the skin is the most common type of malignant human tumor. However, metastatic BCC is a very rare event with weakly effective therapeutic options and a poor prognosis, until a few years ago. In 2012, small-molecule therapies, capable of inactivating the hedgehog signaling pathway and thus reducing tumor growth and progression, were introduced into clinical practice for the treatment of patients with advanced BCC. We present retrospectively 2 personal cases of metastatic BCC of the skin, from the premolecular therapy era, from primary tumors that arose years before in the head and neck area. The former case occurred in a 45-year-old woman with a history of recurrent BCC of the retroauricular skin who eventually died due to diffuse metastatic spread. The latter case concerned a 70-year-old man also with a history of recurrent BCC of the nasal-perinasal skin who developed multiple subcutaneous and lymph node metastases in the neck. In both cases, the diagnoses were based on biopsies of the metastatic sites. The first patient died 5 months after the diagnosis of metastatic disease, while the second was alive and disease-free 2 years after neck lymph node dissection and external radiation therapy, and then lost to follow-up. We extensively discuss several tumor entities with basal or basaloid features that may enter the differential diagnosis with BCC in metastatic sites. In addition, we briefly summarize the advances in clinical therapeutics using small molecules, which are now an integral part of the treatment of such advanced BCC cases.

Metastatic Basal Cell Carcinoma: Case Report and Review of the Literature

Basal cell carcinoma (BCC) is the most commonly occurring carcinoma among humans. However, despite their overall frequency, cases of BCC featuring metastases are extremely rare. We present the case of a male patient with BCC located in the chest, measuring 10 cm and with an evolution of 15 years. After several years, an axillary recurrence developed as a tumor mass affecting the lymph nodes. After 14 months, a further lymph node recurrence was observed and resected. Six months later, a pulmonary nodule was detected, which was resected with tumor-free margins. Histopathological report revealed infiltration by BCC. After 13 years of follow-up (after the removal of the primary tumor), the patient remained alive and received close clinicoradiological monitoring. Taking advantage of this opportunity, we also provide a brief review of the corresponding literature.

Safety and Tolerability of Sonic Hedgehog Pathway Inhibitors in Cancer

The hedgehog pathway, for which sonic hedgehog (Shh) is the most prominent ligand, is highly conserved and is tightly associated with embryonic development in a number of species. This pathway is also tightly associated with the development of several types of cancer, including basal cell carcinoma (BCC) and acute promyelocytic leukemia, among many others. Inactivating mutations in Patched-1 (PTCH1), leading to ligand-independent pathway activation, are frequent in several cancer types, but most prominent in BCC. This has led to the development of several compounds targeting this pathway as a cancer therapeutic. These compounds target the inducers of this pathway in Smoothened (SMO) and the GLI transcription factors, although targeting SMO has had the most success. Despite the many attempts at targeting this pathway, only three US FDA-approved drugs for cancers affect the Shh pathway. Two of these compounds, vismodegib and sonidegib, target SMO to suppress signaling from either PTCH1 or SMO mutations that lead to upregulation of the pathway. The other approved compound is arsenic trioxide, which can suppress this pathway at the level of the GLI proteins, although current evidence suggests it also has other targets. This review focuses on the safety and tolerability of these clinically approved drugs targeting the Shh pathway, along with a discussion on other Shh pathway inhibitors being developed.

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.

Long-term efficacy and safety of sonidegib in patients with locally advanced and metastatic basal cell carcinoma: 30-month analysis of the randomized phase 2 BOLT study

BACKGROUND

Patients with locally advanced basal cell carcinoma (laBCC) or metastatic BCC (mBCC), two difficult-to-treat populations, have had limited treatment options. Sonidegib, a hedgehog pathway inhibitor (HPI), was approved in laBCC based on results from the BOLT trial.

OBJECTIVE

To evaluate long-term efficacy and safety of sonidegib in laBCC and mBCC in the BOLT 18- and 30-month analyses.

METHODS

BOLT (NCT01327053, ClinicalTrials.gov), a double-blind phase 2 study, enrolled patients from July 2011 until January 2013. Eligible HPI-treatment-naïve patients with laBCC not amenable to curative surgery/radiotherapy or mBCC were randomized 1 : 2 to sonidegib 200 mg (laBCC, n = 66; mBCC, n = 13) or 800 mg (laBCC, n = 128; mBCC, n = 23). Tumour response was assessed per central and investigator review.

RESULTS

With 30 months of follow-up, among patients treated with sonidegib 200 mg (approved dose), objective response rates were 56.1% (central) and 71.2% (investigator) in laBCC and 7.7% (central) and 23.1% (investigator) in mBCC. Tumour responses were durable as follows: median duration of response was 26.1 months (central) and 15.7 months (investigator) in laBCC and 24.0 months (central) and 18.1 months (investigator) in mBCC. Five patients with laBCC and three with mBCC in the 200-mg arm died. Median overall survival was not reached in either population; 2-year overall survival rates were 93.2% (laBCC) and 69.3% (mBCC). In laBCC, efficacy was similar regardless of aggressive or non-aggressive histology. Sonidegib 200 mg continued to have a better safety profile than 800 mg, with lower rates of grade 3/4 adverse events (43.0% vs. 64.0%) and adverse events leading to discontinuation (30.4% vs. 40.0%).

CONCLUSION

Sonidegib continued to demonstrate long-term efficacy and safety in these populations. These data support the use of sonidegib 200 mg per local treatment guidelines.

Emergence of chemoresistance in a metastatic basal cell carcinoma patient after complete response to hedgehog pathway inhibitor vismodegib (GDC-0449)

Vismodegib (GDC-0449, Genentech, USA), a small molecule inhibitor of the Hedgehog signalling pathway, has potent anti-tumour activity in advanced basal cell carcinoma (BCC). We report a case of a 67-year-old Australian man with metastatic BCC including pulmonary disease with malignant effusion who showed a dramatic complete response to vismodegib but subsequently experienced a recurrence of pulmonary disease, indicative of chemoresistance to vismodegib. This case is the first to illustrate chemoresistance in a patient with metastatic BCC, and demonstrates the need for closely monitoring metastatic BCC patients even after an apparently complete response.

Advanced basal cell carcinoma, the hedgehog pathway, and treatment options - role of smoothened inhibitors

Cutaneous basal cell carcinoma (BCC) is the most common human cancer and its incidence is rising worldwide. Ultraviolet radiation exposure, including tanning bed use, as well as host factors play a role in its development. The majority of cases are treated and cured with local therapies including surgery. Yet, the health care costs of diagnosis and treatment of BCCs in the US is substantial. In the United States, the cost of nonmelanoma skin cancer care in the Medicare population is estimated to be US$426 million per year. While rare, locally advanced BCCs that can no longer be controlled with surgery and/or radiation, and metastatic BCCs do occur and can be associated with significant morbidity and mortality. Vismodegib (GDC-0449), a smoothened inhibitor targeted at the hedgehog pathway, is the first US Food and Drug Association (FDA)-approved agent in the treatment of locally advanced, unresectable, and metastatic BCCs. This class of agents appears to be changing the survival rates in advanced BCC patients, but appropriate patient selection and monitoring are important. Multidisciplinary assessments are essential for the optimal care and management of these patients. For some patients with locally advanced BCC, treatment with a hedgehog inhibitor may eliminate the need for an excessively disfiguring or morbid surgery.

Basal cell carcinoma: a comprehensive review for the radiologist

OBJECTIVE. Basal cell carcinoma (BCC) is the most common malignancy in the United States. The purpose of this article is to provide a comprehensive description of the clinicopathologic features, diagnostic workup, staging, treatment, and follow-up of BCC. CONCLUSION. Radiology plays an important role in the evaluation and staging of locally advanced and metastatic BCC. MRI is the modality of choice for assessing perineural disease and is equivalent or superior to CT for evaluating bony involvement. CT and PET/CT are used to evaluate metastatic disease.

Advances in the management of basal cell carcinoma

Basal cell carcinoma (BCC), a malignant neoplasm derived from non-keratinizing cells that originate in the basal layer of the epidermis, is the most common cancer in humans. Several factors such as anatomic location, histologic features, primary or recurrent tumors, and patient characteristics influence the choice of treatment modality for BCC. Mohs micrographic surgery (MMS) facilitates optimal margin control and conservation of normal tissue for the management of BCC; however, other treatment modalities may also be implemented in the correct clinical scenario. Other treatment modalities that will be reviewed include simple excision, electrodesiccation and curettage, cryotherapy, topical immunotherapy and chemotherapy, photodynamic therapy, and radiation therapy. In addition, targeted molecular therapeutic options for the treatment of advanced or metastatic BCC will be discussed in this informal review based on recent literature obtained by using PubMed with relevant search terms.

Photodynamic therapy with methyl aminolevulinate in the treatment of basal cell carcinoma

The article presents the results of the studies on the effectiveness of treatment basal cell carcinoma of the skin with photodynamic therapy with 5-aminolevulinic acid and methyl aminolevulinate. The results of the comparing trials between photodynamic therapy with methyl aminolevulinate and different other treatment modalities are presented.

Clinical benefit assessment of vismodegib therapy in patients with advanced basal cell carcinoma

PURPOSE

Vismodegib was approved for the treatment of advanced basal cell carcinoma (aBCC) based on the pivotal ERIVANCE BCC study. The primary endpoint (objective response rate [ORR]) was assessed 9 months after the last patient was enrolled. To confirm the clinical benefit of vismodegib, an additional analysis was performed 12 months after the primary analysis.

MATERIALS AND METHODS

ERIVANCE BCC was a multicenter, nonrandomized, two-cohort study of 104 patients with histologically confirmed aBCC. Patients received 150 mg oral vismodegib daily until disease progression, intolerable toxicity, or withdrawal. An independent review panel comprising three expert clinicians reviewed patient photographs individually and as a consensus panel to evaluate baseline disease severity and clinical benefit after vismodegib treatment in 71 patients with locally advanced BCC (laBCC).

RESULTS

Sixty-three patients were efficacy evaluable; baseline and postprogression photographs for 61 were available for review. Baseline disease severity was judged as 5 or 4 (very severe or moderately severe) in 71.4%. Clinical benefit was observed in 76.2% (significant: 65.1%; some: 11.1%). Interpanelist agreement (maximum difference ≤1 point among panelists' scores in 65.1% and 87.3% of patients for clinical benefit and baseline disease severity, respectively) and correlation between individual and panel reviews were strong. Clinical benefit scores showed good concordance with the protocol-specified ORR obtained by an independent review facility and with investigator-assessed response.

CONCLUSION

Clinical benefit assessed by independent review based on expert clinical judgment provides strong evidence that treatment with vismodegib results in clinically meaningful and durable responses in patients with laBCC.

Advanced Basal Cell Carcinoma: Epidemiology and Therapeutic Innovations

Advanced basal cell carcinomas are a subset of basal cell carcinomas that can be difficult to treat either due to their local invasiveness, proximity to vital structures, or metastasis. The incidence of all basal cell carcinoma is increasing in the United States, although it is not known whether advanced basal cell carcinomas (aBCCs) are also increasing. Recently, highly targeted therapy based on knowledge of the basal cell carcinoma pathogenesis has become available either commercially or through human clinical trials. These orally available drugs inhibit the Hedgehog signaling pathway, and lead to advanced basal cell carcinoma shrinkage that can enable preservation of adjacent vital organs. In this review, we outline the role of Hedgehog pathway inhibitors as well as other treatment modalities such as excision, radiotherapy and more traditional chemotherapy in treating advanced basal cell carcinomas. We also highlight current gaps in knowledge regarding the use and side effects of this targeted therapy.

Metastatic basal cell carcinoma: prognosis dependent on anatomic site and spread of disease

PURPOSE

This review provides a description of the epidemiology and survival outcomes for cases with metastatic basal cell carcinoma (mBCC) based on published reports (1981-2011).

METHODS

A literature search (MEDLINE via PubMed) was conducted for mBCC case reports published in English: 1981-2011. There were 172 cases that met the following criteria: primary BCC located on skin, metastasis confirmed by pathology and metastasis not resulting from direct tumour spread. From these, 100 mBCC cases with explicit information on follow-up time were selected for analysis. Survival analysis was conducted using Kaplan-Meier methods.

RESULTS

Among 100 mBCC cases selected for analysis, including one case with Gorlin syndrome, 50% had regional metastases (RM) and 50% had distant metastases (DM). Cases with DM were younger at mBCC diagnosis (mean age, 58.0 versus 66.3 years for RM; P=0.0013). Among 93 (of 100) cases with treatment information for metastatic disease, more DM cases received chemotherapy (36.2% versus 6.5% for RM), but more RM cases underwent surgery (87.0% versus 40.4% for DM). Among all 100 cases, median survival after mBCC diagnosis was 54 months (95% confidence interval (CI), 24-72), with shorter survival in DM (24 months; 95% CI, 12-35) versus RM cases (87 months; 95% CI, 63-not evaluable).

CONCLUSION

Cases with RM and DM mBCC may have different clinical courses and outcomes. Based on published reports, DM cases were younger at mBCC diagnosis, with shorter median survival than RM cases. This study provides a historical context for emerging mBCC treatments.