Aggressive Squamous Cell Carcinoma in Organ Transplant Recipients

Histological predictors of outcome for cutaneous squamous cell carcinoma in renal transplant patients: A case-control study

Background

Cutaneous squamous cell carcinoma is a significant cause of morbidity for immunosuppressed patients such as organ transplant recipients; however, histological parameters which predict the likelihood of tumor progression are typically based on general population studies in which immunosuppressed patients represent only a small fraction of cases.

Objectives

To determine the histological parameters which have independent prognostic value for cutaneous squamous cell carcinoma arising in renal transplant recipients.

Methods

Case-control study incorporating a retrospective blinded histological review of 70 archived specimens of cutaneous squamous cell carcinoma diagnosed in renal transplant recipients, comprising 10 cases where the tumor had progressed and 60 controls.

Results

Progression was significantly associated with head and neck location, size, depth, poor histological grade, perineural invasion (including small caliber perineural invasion), lymphovascular invasion, and a desmoplastic growth pattern.

Limitations

The retrospective nature and the low number of cases compared to controls.

Conclusion

In immunosuppressed patients both small caliber perineural invasion and a desmoplastic growth pattern may also have prognostic significance in addition to other histological parameters already recognized in formal staging schemes.

Outcomes of Head and Neck Microvascular Free Tissue Transfer for Advanced Cutaneous Squamous Cell Carcinoma: A Comparison of Solid Organ Transplant Recipients to Nontransplant Patients

BACKGROUND

Patients with solid organ transplant (SOT) are at increased risk of developing aggressive cutaneous malignancies due to their immunosuppression, particularly cutaneous squamous cell carcinoma (cSCC).

PURPOSE

There is limited data regarding SOT patients with locally advanced cSCC requiring radical surgery and microvascular free tissue transfer (MVFTT). Our objectives were to characterize outcomes in SOT patients and compare them with a non-SOT cohort.

STUDY DESIGN

This is a retrospective cohort study of patients undergoing MVFTT for advanced cSCC of the head and neck between January 2016 and May 2020 at a tertiary referral center. Patients who underwent MVFTT as part of curative intent surgery for advanced cSCC during the study were considered for inclusion. Exclusion criteria included distant metastasis, palliative intent treatment, age less than 18 years, and lip primaries.

PREDICTOR

The predictor variable was SOT status. A cohort of non-SOT patients was matched to the SOT cohort based on age, smoking status, tumor stage, and defect size.

MAIN OUTCOME VARIABLES

The primary reconstructive outcome was the major surgical complications and secondary outcome measures included major medical complications and minor surgical complications. The primary oncologic outcome was overall survival and the secondary outcome was disease-specific survival. The primary predictor was transplant status.

COVARIATES

Covariates included patient comorbidities, prior treatment, tumor stage, type of reconstruction, pathologic findings, and adjuvant therapy.

ANALYSIS

Continuous and categorical variables were compared using Student's T test and Fisher's exact test. Survival was calculated using the Kaplan-Meier method and differences in survival between groups were calculated using the log-rank test. Statistical significance was set a priori at P ≤ .05.

RESULTS

Fourteen SOT and 14 matched non-SOT patients met inclusion criteria. There was not a statistically significant difference in the rate of major surgical complications (7 vs 7%, P = .74) between the SOT and non-SOT cohorts. Rates of minor (21 vs 43%, P = .26) wound complications and medical complications (0 vs 14%, P = .24) were also similar between the SOT and non-SOT cohorts. Locoregional recurrences and distant metastasis were more common for SOT patients, though this was not statistically significant. Overall survival was significantly worse for SOT patients (21.7 vs 31.0 months, P = .04), though there was not a significant difference in disease-free survival (9.8 vs 31.0 months, P = .17).

CONCLUSIONS AND RELEVANCE

MVFTT in the management of SOT patients with locally advanced head and neck cSCC demonstrates similar complication rates with non-SOT patients. While survival and oncologic outcomes are worse in the SOT cohort, aggressive surgical intervention with MVFTT can be performed with comparable complication rates to patients without a history of SOT.

T Cell Immunity in Human Papillomavirus-Related Cutaneous Squamous Cell Carcinoma-A Systematic Review

Cutaneous squamous cell carcinoma (cSCC) is an invasive malignancy that disproportionately afflicts immunosuppressed individuals. The close associations of cSCC with immunosuppression and human papillomavirus (HPV) infection beget the question of how these three entities are intertwined in carcinogenesis. By exploring the role of T cell immunity in HPV-related cSCC based on the existing literature, we found that the loss of T cell immunity in the background of β-HPV infection promotes cSCC initiation following exposure to environmental carcinogens or chronic trauma. This highlights the potential of developing T-cell centred therapeutic and preventive strategies for populations with increased cSCC risk.

Prognostic Outcomes of Cutaneous Squamous Cell Carcinoma in Solid Organ Transplant Recipients: A Retrospective Comparative Cohort Study

INTRODUCTION

Cutaneous squamous cell carcinoma (cSCC) is the second most common cutaneous neoplasm, and its incidence is on the rise. While most cSCCs have an excellent prognosis, certain risk factors, especially immunosuppression, have been associated with higher rates of local recurrence (LR), metastasis, and poor prognosis. This study aims to assess the risk factors for LR and metastasis development in cSCC among solid organ transplant recipients (SOTRs) and compare these rates with those in immunocompetent patients.

MATERIALS AND METHODS

A retrospective observational study included cSCC cases from the University Hospital Reina Sofía in Córdoba, Spain, between 2002 and 2019. Demographic, clinical, and histopathological data were collected. Local recurrence and metastasis rates were analyzed, along with progression-free survival. Univariate analyses were performed to identify prognostic factors in SOTRs.

RESULTS

Among 849 cSCC cases, we found higher rates of local recurrence and metastasis in tumors developed by SOTRs compared to those in immunocompetent individuals. However, no significant differences in local recurrence, metastasis, or progression-free survival were observed between the two groups. Risk factors for adverse outcomes in SOTRs included tumor size > 2 cm, depth > 4 mm, and a higher Clark level. A total of 34.4% of SOTRs developed a second primary cSCC during the follow-up.

CONCLUSIONS

In our study, cSCCs in SOTRs did not exhibit statistically significant differences in the rates of adverse outcomes compared to immunocompetent patients. The prognosis of cSCCs in SOTRs may be more related to other tumor-dependent risk factors than to the immunosuppression status itself. Future studies are needed to refine risk stratification and follow-up protocols to ensure the optimal management of high-risk cSCC cases, particularly among immunosuppressed patients.

Venous Free Flap with Interposition Bypass Graft for Arteriovenous Fistula Preservation: A Case Report

Cutaneous squamous cell carcinoma (CSCC) overlying an arteriovenous fistula (AVF) is rare and presents unique challenges. This case report describes a method of fistula preservation after CSCC excision using a flow-through venous free flap. The saphenous vein of the venous flap was used as flow-through segment for AVF preservation. The flap was inserted along the dorsal aspect of the forearm wound and microvascular anastomosis of the arterial inflow was completed using a vein just proximal to the radiocephalic fistula anastomosis. Venous outflow was established by creating an end-to-end vascular anastomosis between the cephalic vein and the greater saphenous vein. A separate subcutaneous vein was used to provide a low-pressure outflow for the flap to avoid congestion. This case demonstrates an option for AVF preservation that has not been previously described. It also highlights the importance of a multidisciplinary approach for the safe treatment of CSCCs overlying AVFs.

Cancer Mortality Among Solid Organ Transplant Recipients in the United States During 1987-2018

BACKGROUND

Solid organ transplant recipients (ie, "recipients") have elevated cancer risk and reduced survival after a cancer diagnosis. Evaluation of cancer mortality among recipients can facilitate improved outcomes from cancers arising before and after transplantation.

METHODS

We linked the US transplant registry to the National Death Index to ascertain the causes of 126 474 deaths among 671 127 recipients (1987-2018). We used Poisson regression to identify risk factors for cancer mortality and calculated standardized mortality ratios to compare cancer mortality in recipients with that in the general population. Cancer deaths verified with a corresponding cancer diagnosis from a cancer registry were classified as death from pretransplant or posttransplant cancers.

RESULTS

Thirteen percent of deaths were caused by cancer. Deaths from lung cancer, liver cancer, and non-Hodgkin lymphoma (NHL) were the most common. Heart and lung recipients had the highest mortality for lung cancer and NHL, whereas liver cancer mortality was highest among liver recipients. Compared with the general population, cancer mortality was elevated overall (standardized mortality ratio 2.33; 95% confidence interval, 2.29-2.37) and for most cancer sites, with large increases from nonmelanoma skin cancer (23.4, 21.5-25.5), NHL (5.17, 4.87-5.50), kidney cancer (3.40, 3.10-3.72), melanoma (3.27, 2.91-3.68), and, among liver recipients, liver cancer (26.0, 25.0-27.1). Most cancer deaths (93.3%) were associated with posttransplant cancer diagnoses, excluding liver cancer deaths in liver recipients (of which all deaths were from pretransplant diagnoses).

CONCLUSIONS

Improved posttransplant prevention or screening for lung cancer, NHL, and skin cancers and management of liver recipients with prior liver cancer may reduce cancer mortality among recipients.

Use of sirolimus as an adjuvant therapy for kidney transplant recipients with high-risk cutaneous squamous cell carcinomas: a prospective non-randomized controlled study

INTRODUCTION

Previous research demonstrated benefits of late conversion to mTOR inhibitors against cutaneous squamous cell carcinomas (cSCC) in kidney transplant recipients (KTR), despite of poor tolerability. This study investigated whether stepwise conversion to sirolimus monotherapy without an attack dose modified the course of disease with improved tolerability.

METHODS

This prospective exploratory study included non-sensitized KTR with more than 12-months post-transplant, on continuous use of calcineurin inhibitors (CNI)-based therapy, and with poor-prognosis cSCC lesions. Incidence densities of high-risk cSCC over 3-years after conversion to sirolimus-monotherapy were compared to a non-randomized group with high-risk cSCC but unsuitable/not willing for conversion.

RESULTS

Forty-four patients were included (83% male, mean age 60 ± 9.7years, 62% with skin type II, mean time after transplantation 9 ± 5.7years). There were 25 patients converted to SRL and 19 individuals kept on CNI. There was a tendency of decreasing density of incidence of all cSCC in the SRL group and increasing in the CNI group (1.49 to 1.00 lesions/patient-year and 1.74 to 2.08 lesions/patient-year, p = 0.141). The density incidence of moderately differentiated decreased significantly in the SRL group while increasing significantly in the CNI group (0.31 to 0.11 lesions/patient-year and 0.25 to 0.62 lesions/patient-year, p = 0.001). In the SRL group, there were no sirolimus discontinuations, no acute rejection episodes, and no de novo DSA formation. Renal function remained stable.

CONCLUSIONS

This study suggests that sirolimus monotherapy may be useful as adjuvant therapy of high-risk cSCC in kidney transplant recipients. The conversion strategy used was well tolerated and safe regarding key mid-term transplant outcomes.

[Marjolin's ulcer associated with verrucous carcinoma in an immunocompromised patient]

Background

Marjolin's ulcer is the malignant degeneration of any chronic wound, with a latency period from tissue injury to variable malignant transformation that may occur up to 30 years later. Among the associated neoplasms, squamous cell carcinoma (SCC) is the predominant lineage in up to 71% of cases. The verrucous carcinoma variant has been estimated to have a low presentation, being described in the literature as 2% of all SCC and reported anecdotally in immunosuppressed patients, which justifies the objective of this publication.

Clinical case

65-year-old female patient with a history of being a carrier of human immunodeficiency virus (HIV) infection, who presented a verrucous carcinoma associated to a Marjolin ulcer secondary to herpes zoster and infection of soft tissues in the right leg, with a latency period of 10 years from the initial infectious process to histopathological confirmation.

Conclusions

The finding of a verrucous carcinoma on a Marjolin ulcer has been little described in literature, with a lower incidence in the context of a patient with a history of being a carrier of HIV infection, finding 7 case reports, the oldest from 1998. For this reason, it is important to have diagnostic suspicion, to carry out an adequate study protocol and always making clinical-pathological correlation, in order to establish timely and individualized treatment.

Local blockade of tacrolimus promotes T-cell-mediated tumor regression in systemically immunosuppressed hosts

BACKGROUND

Immunosuppressive drugs such as tacrolimus have revolutionized our ability to transplant organs between individuals. Tacrolimus acts systemically to suppress the activity of T-cells within and around transplanted organs. However, tacrolimus also suppresses T-cell function in the skin, contributing to a high incidence of skin cancer and associated mortality and morbidity in solid organ transplant recipients. Here, we aimed to identify a compound capable of re-establishing antitumor T-cell control in the skin despite the presence of tacrolimus.

METHODS

In this study, we performed time-resolved fluorescence resonance energy transfer to identify molecules capable of antagonizing the interaction between tacrolimus and FKBP12. The capacity of these molecules to rescue mouse and human T-cell function in the presence of tacrolimus was determined in vitro, and the antitumor effect of the lead compound, Q-2361, was assessed in "regressor" models of skin cancer in immunosuppressed mice. Systemic CD8 T-cell depletion and analyses of intratumoral T-cell activation markers and effector molecule production were performed to determine the mechanism of tumor rejection. Pharmacokinetic studies of topically applied Q-2361 were performed to assess skin and systemic drug exposure.

RESULTS

Q-2361 potently blocked the interaction between tacrolimus and FKBP12 and reversed the inhibition of the nuclear factor of activated T cells activation by tacrolimus following T-cell receptor engagement in human Jurkat cells. Q-2361 rescued T-cell function in the presence of tacrolimus, rapamycin, and everolimus. Intratumoral injection of Q-2361-induced tumor regression in mice systemically immune suppressed with tacrolimus. Mechanistically, Q-2361 treatment permitted T-cell activation, proliferation, and effector function within tumors. When CD8 T cells were depleted, Q-2361 could not induce tumor regression. A simple solution-based Q-2361 topical formulation achieved high and sustained residence in the skin with negligible drug in the blood.

CONCLUSIONS

Our findings demonstrate that the local application of Q-2361 permits T-cells to become activated driving tumor rejection in the presence of tacrolimus. The data presented here suggests that topically applied Q-2361 has great potential for the reactivation of T-cells in the skin but not systemically, and therefore represents a promising strategy to prevent or treat skin malignancies in immunosuppressed organ transplant recipients.

Immune Checkpoint Inhibitors in Advanced Cutaneous Squamous Cell Carcinoma: Real-World Experience from a Canadian Comprehensive Cancer Centre

Immune checkpoint inhibitors (ICI) cemiplimab and pembrolizumab have revolutionized the treatment of advanced cutaneous squamous cell carcinoma (cSCC). We aimed to evaluate the effectiveness and safety of ICI in a real-world cSCC population, including patients with conditions that would exclude clinical trial participation. In this single-center, retrospective cohort study, we included all non-trial patients with advanced cSCC treated with ICI between 2017 and 2022. We evaluated investigator-assessed best overall response (BOR) and immune-related adverse events (irAEs). We correlated survival outcomes with age, performance status, immune status and irAEs. Of the 36 patients identified, the best overall response (BOR) to ICI was a partial response (PR) in 41.7%, a complete response (CR) in 27.8%, and stable disease in (SD) 13.9%. The progression-free survival (PFS) rate for 1 year was 58.1%; the median PFS was 21.3 months (95% CI 6.4-NE). The 1-year overall survival (OS) was 76.7%, and the median OS was 38.6 months (95% CI 25.4-NE). Immune-compromised patients, ECOG performance 2-3, and age ≥ 75 years were not significantly associated with PFS or OS. IrAE grades 3-4 were seen in 13.9% of patients. In our Canadian experience with real-world patients, ICI was an effective and safe treatment for advanced cSCC patients. Patients achieved great benefits with ICI regardless of age, immune status or ECOG performance status. We acknowledge the small sample size and retrospective methodology as the main limitations of our study.

Basal cell carcinomas in organ transplant recipients versus the general population: clinicopathologic study

Organ transplant recipients (OTRs) are at greater risk of basal cell carcinomas (BCCs) than non-OTRs, but histopathologic differences between BCCs in OTRs and the general population are largely unknown. We compared clinicopathologic features of BCCs in OTRs vs the general population in Queensland, Australia. Details of BCC tumors (site, size, level of invasion, subtype, biopsy procedure) were collected from histopathology reports in two prospective skin cancer studies, one in OTRs and one general-population-based. We used log-binomial regression models to estimate age- and sex-adjusted prevalence ratios (PR) with 95% confidence intervals (CIs) for BCC features. Overall, there were 702 BCCs in 200 OTRs and 1725 BCCs in 804 population cases. Of these, 327 tumors in 128 OTRs were higher risk BCCs (any head and neck BCC; ≥ 2 cm on trunk/extremities), more per person than 703 higher risk BCCs in 457 cases in the general population (chi-square p = 0.008). Among head/neck BCCs, OTRs were more likely than general population cases to have BCCs on scalp/ear than on face/lip/neck (PR = 1.5, 95%CI 1.2-1.8). Although aggressive subtypes were less common among higher risk BCCs in OTRs, BCCs invading beyond the dermis were almost twice as prevalent in OTRs (PR = 1.8, 95% CI 1.3-2.6) than the general population.

Immunosenescence and Skin: A State of Art of Its Etiopathogenetic Role and Crucial Watershed for Systemic Implications

Immunosenescence is a complex multifactorial phenomenon consisting of wide-ranging remodeling of the immune system during the life span, resulting in an age-related qualitative-quantitative decline of immune cells and cytokines. A growing body of evidence in the international literature is highlighting the etiopathogenetic role of skin immunosenescence in the onset of various dermatologic conditions. Skin immunosenescence also serves as an interesting watershed for the onset of system-wide conditions in the context of allergic inflammation. Moreover, in recent years, an increasingly emerging and fascinating etiopathogenetic parallelism has been observed between some mechanisms of immunosenescence, both at cutaneous and systemic sites. This would help to explain the occurrence of apparently unconnected comorbidities. Throughout our review, we aim to shed light on emerging immunosenescent mechanisms shared between dermatologic disorders and other organ-specific diseases in the context of a more extensive discussion on the etiopathogenetic role of skin immunosenescence. A promising future perspective would be to focus on better understanding the mutual influence between skin and host immunity, as well as the influence of high inter-individual variability on immunosenescence/inflammaging. This can lead to a more comprehensive "immunobiographic" definition of each individual.

Resection of Skin Cancer Resulting in Free Vascularized Tissue Reconstruction: Always a Therapeutic Failure?

The globally increasing incidence of cutaneous malignancies leads, in parallel, to increasing numbers of locally advanced skin cancer resulting in reconstructive surgery. Reasons for locally advanced skin cancer may be a patient's neglect or aggressive tumor growth, such as desmoplastic growth or perineural invasion. This study investigates characteristics of cutaneous malignancies requiring microsurgical reconstruction with the aim of identifying possible pitfalls and improving diagnostic and therapeutic processes. A retrospective data analysis from 2015 to 2020 was conducted. Seventeen patients (n = 17) were included. The mean age at reconstructive surgery was 68.5 (±13) years. The majority of patients (14/17, 82%) presented with recurrent skin cancer. The most common histological entity was squamous cell carcinoma (10/17, 59%). All neoplasms showed at least one of the following histopathological characteristics: desmoplastic growth (12/17, 71%), perineural invasion (6/17, 35%), or tumor thickness of at least 6 mm (9/17, 53%). The mean number of surgical resections until cancer-free resection margins (R0) were achieved was 2.4 (±0.7). The local recurrence rate and the rate of distant metastases were 36%. Identified high-risk neoplastic characteristics, such as desmoplastic growth, perineural invasion, and a tumor depth of at least 6 mm, require a more extensive surgical treatment without concerns about defect size.

Molecular Alterations in Cutaneous Squamous Cell Carcinoma in Immunocompetent and Immunosuppressed Hosts-A Systematic Review

The characterization of cutaneous squamous cell carcinoma (cSCC) at the molecular level is lacking in the current literature due to the high mutational burden of this disease. Immunosuppressed patients afflicted with cSCC experience considerable morbidity and mortality. In this article, we review the molecular profile of cSCC among the immunosuppressed and immunocompetent populations at the genetic, epigenetic, transcriptomic, and proteometabolomic levels, as well as describing key differences in the tumor immune microenvironment between these two populations. We feature novel biomarkers from the recent literature which may serve as potential targets for therapy.

FGFR2c Upregulation Contributes to Cancer-Associated Fibroblast Program Activation and to Enhanced Autophagy in Actinic Keratosis-Derived Dermal Fibroblasts: A Possible Role in Precancerous Cell/Stromal Cell Crosstalk

Actinic keratosis (AK) is a preneoplastic skin disorder which can rapidly progress to cutaneous squamous cell carcinomas (SCCs). In light of our previous findings, indicating a possible oncogenic role of the mesenchymal isoform of FGFR2 (FGFR2c) aberrantly expressed in AK keratinocytes, we analyzed the possible tumor-promoting role of this receptor in the stromal AK counterpart in this work. Molecular analysis showed that, particularly in early AK lesions, FGFR2c dermal upregulation is accompanied by the downregulation of the cancer-associated fibroblasts (CAF) transcription repressor CSL, the upregulation of the CAF activator ULK3, and the consequent CAF gene induction. Immunofluorescence and molecular analysis, coupled with silencing approaches by siRNA, applied on primary cultures of KIN I-derived fibroblasts, indicated that FGFR2c upregulation contribute to CAF signature and the increased autophagy in response to FGF2. Magnetic bead-based multiplex assay, combined with FGFR2 signaling shut-off approaches, indicated that, especially in response to FGF2, IL-6 secretion could depend on FGFR2c high expression and signaling, suggesting the possible establishment of FGFR2c-dependent secretory autophagy, contributing to tumor-promoting factor release. Overall, our results identified FGFR2c as a signaling molecule involved in controlling precancerous/stromal cell oncogenic crosstalk, pointing to this receptor as a possible early molecular marker predictive for AK’s rapid malignant progression.

Cutaneous Squamous Cell Carcinoma in Immunocompromised Patients—A Comparison between Different Immunomodulating Conditions

Background: Immunosuppression is strongly associated with an increased risk of developing cutaneous squamous cell carcinoma (cSCC). Studies on solid organ transplant recipients (SOTR) and chronic lymphocytic leukemia (CLL) patients have already demonstrated higher rates of aggressive cSCC tumors in these populations compared to immunocompetent controls. Studies on other immunosuppressed patient groups are scarce. This study was aimed at assessing the effects of different immunomodulating conditions on patients diagnosed with cSCC. We sought to compare the clinical features, treatments, and survival rates among the different study groups, as well as outcomes to those of immunocompetent controls with cSCC. Methods: A retrospective analysis of 465 cSCC patients, both immunosuppressed (IS) and immunocompetent controls. Etiologies for immunosuppression included SOTR, CLL, chronic kidney disease (CKD), psoriasis, rheumatoid arthritis (RA) and systemic lupus erythematous (SLE). Results: Compared to the control group, IS patients demonstrated several significant differences. These include higher rates of positive resection margins, higher recurrence rates, and multiple SCC tumors. Patients in the IS group, who were also given immunomodulating agents, demonstrated even lower survival rates. Cox regression analysis demonstrated statistically significant decreased overall survival (OS) rates for IS patients compared to the controls (OR = 1.9, p = 0.031). SOTR patients tend to have multiple cSCC tumors (35%), with the highest number of primary tumors compared to controls (2.54 tumors per patient on average, p < 0.001), but also compared to all other IS groups. The average SCC lesion size in the SOTR group was the smallest, measuring at 13.5 mm, compared to the control group and all other IS groups. Decreased survival rates were seen on Cox regression analysis compared to controls (HR = 2.4, p = 0.001), but also to all other IS groups. CLL patients also had the highest rates of positive margins compared to controls (36% vs. 9%, p < 0.01) and to all other IS groups. They were also most likely to get adjuvant or definitive oncological treatments, either radiotherapy or chemotherapy, compared to controls (36% vs. 15%, p = 0.02) and to other IS groups. Patients in the CKD group demonstrated the highest rates for multiple cSCC (OR = 4.7, p = 0.001) and the worst rates of survival on Cox regression analysis (HR = 3.2, p = 0.001). Both rheumatoid arthritis and psoriasis patients demonstrated the shortest disease-free survival rates (2.9y ± 1.1, 2.3y ± 0.7, respectively), compared to controls (4.1y ± 2.8) and to all other IS groups. Conclusions: Among cSCC patients, immunosuppression due to SOTR, CLL, CKD, RA, and psoriasis is associated with worse outcomes compared to controls and other IS groups. These patients should be regarded as high-risk for developing aggressive cSCC tumors. This study is the first to assess and compare cSCC outcomes among multiple IS patient groups.

HLA expression as a risk factor for metastases of cutaneous squamous-cell carcinoma in organ- transplant recipients

BACKGROUND

Solid organ-transplant recipients (SOTR) have an increased risk of cutaneous squamous-cell carcinoma (cSCC), metastasis and death from cSCC. In immunocompetent patients with mucosal SCC, downregulation of HLA class I is associated with poor prognosis. Since the degree of HLA expression on tumor cells could play a role in immunogenicity and pathophysiology of cSCC metastasis, we hypothesized that decreased HLA expression is associated with an increased risk of metastasis.

METHODS

We compared HLA expression between primary metastasized cSCCs, their metastases, and non-metastasized cSCCs from the same patients. Samples were stained for HLA-A, HLA-B/-C and quantified by calculating the difference in immunoreactivity score (IRS) of the primary cSCC compared with all non-metastasized cSCCs.

RESULTS

The mean IRS score for HLA-B/C expression was 2.07 point higher in metastasized compared to non-metastasized cSCCs (p = 0.065, 95 % CI -0.18-4.32). 83.3 % of the primary metastasized cSCCs had an IRS score of 4 or higher, compared to 42.9 % in non-metastasized cSCCs. Moderately to poorly differentiated cSCCs had more HLA class I expression compared to well-differentiated cSCCs.

CONCLUSION

Contrary to immunocompetent patients, HLA-B/C expression tends to be upregulated in metastasized cSCC compared to non-metastasized cSCC in SOTR, suggesting that different tumor escape mechanisms play a role in SOTR compared to immunocompetent patients.

A broadly protective vaccine against cutaneous human papillomaviruses

Skin colonization by human papillomavirus (HPV) is typically related to inconspicuous cutaneous infections without major disease or complications in immunocompetent individuals. However, in immunosuppressed patients, especially organ transplanted recipients, cutaneous HPV infections may cause massive, highly spreading and recurrent skin lesions upon synergism with UV-exposure. Current HPV prophylactic vaccines are not effective against cutaneous HPV types (cHPV). By applying a modular polytope-based approach, in this work, we explored different vaccine candidates based on selected, tandemly arranged cHPV-L2 epitopes fused to thioredoxin (Trx) as a scaffold protein. Upon conversion to heptameric nanoparticles with the use of a genetically fused oligomerization domain, our candidate Trx-L2 vaccines induce broadly neutralizing immune responses against 19 cHPV in guinea pigs. Similar findings were obtained in mice, where protection against virus challenge was also achieved via passive transfer of immune sera. Remarkably, immunization with the candidate cHPV vaccines also induced immune responses against several mucosal low- and high-risk HPV types, including HPV16 and 18. Based on cumulative immunogenicity data but also on ease and yield of production, we identified a lead vaccine candidate bearing 12 different cHPV-L2 epitopes that holds great promise as a scalable and GMP production-compatible lead molecule for the prevention of post-transplantation skin lesions caused by cHPV infection.

Immunotherapy for the Treatment of Squamous Cell Carcinoma: Potential Benefits and Challenges

Melanoma and nonmelanoma skin cancers (NMSCs) are recognized as among the most common neoplasms, mostly in white people, with an increasing incidence rate. Among the NMSCs, squamous cell carcinoma (SCC) is the most prevalent malignancy known to affect people with a fair complexion who are exposed to extreme ultraviolet radiation (UVR), have a hereditary predisposition, or are immunosuppressed. There are several extrinsic and intrinsic determinants that contribute to the pathophysiology of the SCC. The therapeutic modalities depend on the SCC stages, from actinic keratosis to late-stage multiple metastases. Standard treatments include surgical excision, radiotherapy, and chemotherapy. As SCC represents a favorable tumor microenvironment with high tumor mutational burden, infiltration of immune cells, and expression of immune checkpoints, the SCC tumors are highly responsive to immunotherapies. Until now, there are three checkpoint inhibitors, cemiplimab, pembrolizumab, and nivolumab, that are approved for the treatment of advanced, recurrent, or metastatic SCC patients in the United States. Immunotherapy possesses significant therapeutic benefits for patients with metastatic or locally advanced tumors not eligible for surgery or radiotherapy to avoid the potential toxicity caused by the chemotherapies. Despite the high tolerability and efficiency, the existence of some challenges has been revealed such as, resistance to immunotherapy, less availability of the biomarkers, and difficulty in appropriate patient selection. This review aims to accumulate evidence regarding the genetic alterations related to SCC, the factors that contribute to the potential benefits of immunotherapy, and the challenges to follow this treatment regime.

Lymphocyte subsets and Langerhans cells in the skin of kidney transplant recipients under three different immunosuppressive regimens

BACKGROUND

Renal transplant recipients (RTRs) are at increased risk of developing skin cancer; however, the role of immunosuppression is not yet fully understood. In this study, we evaluated the immunohistochemical changes in the skin of RTRs under three different immunosuppression regimens: mTOR inhibitors (mTORi), sirolimus or everolimus, mycophenolic acid (MPA) precursors such as mycophenolate sodium or mofetil, or azathioprine (AZA).

METHODS

We evaluated biopsies of sun-exposed and sun-protected skin for immunohistochemical quantification of B lymphocytes (CD20+), T lymphocytes (CD3+, CD4+, and CD8+), and Langerhans cells (LCs) (CD1a+) in 30 RTRs and 10 healthy controls. The RTRs were divided into three groups: mTORi (n = 10), MPA (n = 10), and AZA (n = 10).

RESULTS

No differences were observed in the number of B lymphocytes. However, a significant decrease in the number of T lymphocytes and LCs was observed in both sun-protected and sun-exposed skin in the AZA and MPA groups, although to a lesser degree in the latter group. The skin of the mTORi group did not differ from that of the control group in terms of the number of B and T lymphocytes and LCs.

CONCLUSIONS

Patients treated with mTORi exhibit preserved cellular elements related to cutaneous immune surveillance. The use of AZA induced a greater degree of skin immunosuppression than in the control group, as demonstrated by the decrease in T lymphocytes and LCs.

Cutaneous squamous cell carcinoma arising in immunosuppressed patients: a systematic review of tumor profiling studies

As solid organ transplantation becomes more prevalent, more individuals are living as members of the immunosuppressed population with an elevated risk for cutaneous squamous cell carcinoma (cSCC). Although great progress has been made in understanding the pathogenesis of cSCC in general, little is known about the drivers of tumorigenesis in immunosuppressed patients and organ-transplant recipients, specifically. This systematic review sought to synthesize information regarding the genetic and epigenetic alterations as well as changes in protein and mRNA expression that place this growing population at risk for cSCC, influence treatment response, and promote tumor aggressiveness. This review will provide investigators with a framework to identify future areas of investigation and clinicians with additional insight into how to best manage these patients.

Update on Management Recommendations for Advanced Cutaneous Squamous Cell Carcinoma

Simple Summary

Cutaneous squamous cell carcinoma (cSCC) is the second most common form of skin cancer, which predominantly occurs on the head and neck. Early detection and treatment of primary tumours is crucial to limit progression and local invasion of deep tissues. While high-risk markers of poor prognosis have been identified, factors predicting regional control or survival remain uncertain. Therefore, diagnosis and management of cSCC should be performed individually, considering patient’s clinicopathological profile and the best available treatment options. Surgical excision, radiotherapy, and/or systemic treatments can be selected depending on patient’s status and tumour stage. Considering that a more comprehensive assessment will be provided by a multidisciplinary team, we aimed to generate a practical document that may assist oncologists and dermatologists on the prognosis, diagnosis, management, and follow-up of patients with advanced cSCC.

Abstract

Cutaneous squamous cell carcinoma (cSCC) is the second most common form of skin cancer, the incidence of which has risen over the last years. Although cSCC rarely metastasizes, early detection and treatment of primary tumours are critical to limit progression and local invasion. Several prognostic factors related to patients’ clinicopathologic profile and tumour features have been identified as high-risk markers and included in the stratification scales, but their association with regional control or survival is uncertain. Therefore, decision-making on the diagnosis and management of cSCC should be made based on each individual patient’s characteristics. Recent advances in non-invasive imaging techniques and molecular testing have enhanced clinical diagnostic accuracy. Surgical excision is the mainstay of local treatment, whereas radiotherapy (RT) is recommended for patients with inoperable disease or in specific circumstances. Novel systemic treatments including immunotherapies and targeted therapies have changed the therapeutic landscape for cSCC. The anti-PD-1 agent cemiplimab is currently the only FDA/EMA-approved first-line therapy for patients with locally advanced or metastatic cSCC who are not candidates for curative surgery or RT. Given the likelihood of recurrence and the increased risk of developing multiple cSCC, close follow-up should be performed during the first years of treatment and continued long-term surveillance is warranted.

Cutaneous Squamous Cell Carcinoma: The Frontier of Cancer Immunoprevention

Cutaneous squamous cell carcinoma (cSCC) is the second most common cancer, with its incidence rising steeply. Immunosuppression is a well-established risk factor for cSCC, and this risk factor highlights the critical role of the immune system in regulating cSCC development and progression. Further highlighting the nature of cSCC as an immunological disorder, substantial evidence demonstrates a tight association between cSCC risk and age-related immunosenescence. Besides the proven efficacy of immune checkpoint blockade therapy for advanced cSCC, novel immunotherapy that targets cSCC precursor lesions has shown efficacy for cSCC prevention. Furthermore, the appreciation of the interplay between keratinocytes, commensal papillomaviruses, and the immune system has revealed the possibility for the development of a preventive cSCC vaccine. cSCC shares fundamental aspects of its origin and pathogenesis with mucosal SCCs. Therefore, advances in the field of cSCC immunoprevention will inform our approach to the management of mucosal SCCs and potentially other epithelial cancers.

Treatment of metastatic cutaneous squamous cell carcinoma in a solid organ transplant recipient with programmed death-1 checkpoint inhibitor therapy

Limited data exist on the use of immune checkpoint inhibitors (ICI) for the treatment of metastatic cutaneous squamous cell carcinoma (CSCC) in solid organ transplant recipients (SOTR). We report a case of a SOTR who developed metastatic disease following multiple surgeries, three cycles of adjuvant radiotherapy, and minimization of immunosuppression. He was subsequently treated with pembrolizumab and achieved a complete response. However, the patient developed ICI-induced allograft rejection requiring therapy discontinuation. The allograft was salvaged following IVIg and steroids. The patient developed recurrent disease which failed rechallenge with pembrolizumab but achieved a partial response following cemiplimab administration. This case illustrates the potential to treat metastatic CSCC in a SOTR with anti-programmed death-1 therapy and preserve graft function despite allograft rejection.

Hide-and-seek: Neurotropic squamous cell carcinoma of the periorbital region - a series of five cases and review of the literature

Squamous cell carcinoma is the second most common malignancy of the skin after basal cell carcinoma and mainly found in sun‐exposed areas such as the face. This mostly locally destructive malignancy may show invasive growth and insidious mechanisms of dissemination such as perineural invasion. Periorbital squamous cell carcinoma is associated with perineural invasion in up to 14 % of cases. Specifically in this region, the proximity to cranial nerves and therefore the associated risk of progression to the central nervous system are associated with poor prognosis. The clinically concealed character of this entity often leads to a delay in diagnosis and consequently makes complete resection and reconstruction demanding. Careful clinical evaluation often hints at perineural invasion before obtaining histology.

Aside from presenting five challenging cases, this work analyzes risk factors, clinical as well as histological features, and treatment options for periorbital squamous cell carcinoma with perineural invasion.

Hide-and-seek: Neurotropes Plattenepithelkarzinom der periorbitalen Region - eine Fallserie und Übersichtsarbeit aktueller Literatur

Das Plattenepithelkarzinom ist nach dem Basalzellkarzinom das zweithäufigste Malignom der Haut und wird vorwiegend an sonnenexponierten Stellen wie der Gesichtshaut diagnostiziert. Diese meist lokal destruktiv wachsende Malignität kann durchaus auch invasives Wachstumsverhalten, wie perineurale Ausbreitungsmechanismen, aufweisen. Das Plattenepithelkarzinom der periorbitalen Region ist in bis zu 14 % der Fälle mit perineuraler Invasion assoziiert. Vor allem in diesem Bereich birgt die anatomische Nähe zu den Hirnnerven das Risiko einer Progression Richtung zentrales Nervensystem, was mit einer schlechteren Prognose assoziiert ist. Der klinisch unauffällige Charakter dieser Entität resultiert oft in einer Verzögerung der definitiven Diagnosestellung, wodurch die vollständige Resektion und anschließende Rekonstruktion erschwert werden. Eine aufmerksame klinische Evaluierung kann bereits vor Erlangen histologischer Befunde Hinweise für ein perineurales Wachstum liefern. Neben fünf herausfordernden Fällen analysiert diese Arbeit Risikofaktoren, klinische als auch histologische Merkmale und Behandlungsoptionen des periorbitalen Plattenepithelkarzinoms mit perineuraler Invasion.

Cutaneous squamous cell carcinoma staging may influence management in users: A survey study

Purpose

This study aims to determine whether there is consensus regarding staging and management of cutaneous squamous cell carcinoma (CSCC) across the various specialties that manage this disease.

Materials and Methods

A survey regarding CSCC high‐risk features, staging, and management was created and emailed to cutaneous oncology experts including dermatology, head and neck surgery/surgical oncology, radiation oncology, and medical oncology.

Results

One hundred fifty‐six (46%) of 357 invited physicians completed the survey. Depth of invasion (92%), perineural invasion (99%), histologic differentiation (85%), and patient immunosuppression (90%) achieved consensus (>80%) as high‐risk features of CSCC. Dermatologists were more likely to also choose clinical tumor diameter (79% vs. 54%) and histology (99% vs. 66%) as a high‐risk feature. Dermatologists were also more likely to utilize the Brigham and Women's Hospital (BWH) staging system alone or in conjunction with American Joint Committee on Cancer (AJCC) (71%), whereas other cancer specialists (OCS) tend to use only AJCC (71%). Respondents considered AJCC T3 and higher (90%) and BWH T2b and higher (100%) to be high risk and when they consider radiologic imaging, sentinel lymph node biopsy, post‐operative radiation therapy, and increased follow‐up. Notably, a large number of respondents do not use staging systems or tumor stage to determine treatment options beyond surgery in high‐risk CSCC.

Conclusion

This survey study highlights areas of consensus and differences regarding the definition of high‐risk features of CSCC, staging approaches, and management patterns between dermatologists and OCS. High‐risk CSCC is defined as, but not limited to, BWH T2b and higher and AJCC T3 and higher, and these thresholds can be used to identify cases for which treatment beyond surgery may be considered. Dermatologists are more likely to utilize BWH staging, likely because BWH validation studies showing advantages over AJCC were published in dermatology journals and discussed at dermatology meetings. Additional data are necessary to develop a comprehensive risk‐based management approach for CSCC.

Cumulative incidence and disease-specific survival of metastatic cutaneous squamous cell carcinoma: A nationwide cancer registry study

BACKGROUND

Cutaneous squamous cell carcinoma (cSCC) represents the most serious form of keratinocyte cancers because of its metastatic potential. Studies on nationwide incidence and disease-specific survival rates of metastatic cSCC (mcSCC) are lacking.

OBJECTIVE

To investigate the cumulative incidence and disease-specific survival of patients with mcSCC in the Dutch population and assess patient-based risk factors.

METHODS

We conducted a nationwide cancer registry study including all patients with the first cSCC in 2007 or 2008, using data from the Netherlands Cancer Registry, the nationwide network and registry of histopathology and cytopathology, and Statistics Netherlands. Cumulative incidence and Kaplan-Meier curves were calculated, and time-dependent Cox proportional hazards regression analyses were used.

RESULTS

Of the 11,137 patients, metastases developed in 1.9% (n = 217). The median time to metastasis was 1.5 years (interquartile range 0.6-3.8 years). The risk factors were age (adjusted hazard ratio [aHR] 1.03, 95% CI 1.02-1.05), male sex (aHR 1.7, 95% CI 1.3-2.3), and immunosuppression (aHR [organ transplant recipient] 5.0, 95% CI 2.5-10.0; aHR [hematologic malignancy] 2.7, 95% CI 1.6-4.6). The 5-year disease-specific survival for patients with mcSCC was 79.1%.

LIMITATIONS

Only histopathologically confirmed mcSCCs were included.

CONCLUSION

About 2% of cSCCs metastasize, with higher risk for men, increasing age, and immunocompromised patients. Disease-specific survival for patients with mcSCC is high.

Epidemiology of advanced cutaneous squamous cell carcinoma

Cutaneous invasive squamous cell carcinoma (cSCC) most commonly presents as a typically indolent tumour with five-year cure rates of >90%. Advanced cSCC has been defined as locally advanced or metastatic (locoregional or distant) cSCC. The epidemiological data on advanced cSCC are rare due to underreporting or exclusion of cSCC from national cancer registries. Although the frequency of local recurrence has been reported, there is no clear evidence on the incidence or mortality of locally advanced cSCCs, e.g. locally infiltrating or locally recurrent cSCCs that are not further amenable to curative surgery or radiotherapy. This gap of knowledge on the epidemiology of locally advanced cSCC, highlights the need for standardisation in defining and reporting both locally advanced and metastatic cSCC. Even though metastatic cSCCs are a small part of cSCCs (3%-5%), their aggressive characteristics contribute to significant morbidity, higher mortality and are those likely to require systemic treatments. Locally recurrent and metastatic cSCC may occur more frequently in high-risk cSCCs (up to 35%). The site of metastasis involves in the vast majority the regional lymph nodes, with the head and neck lymph nodes or parotid most commonly affected. Metastasis occurs mostly within 2-3 years of the primary cSCC diagnosis. The knowledge of the incidence and prognosis of advanced cSCC and the risk stratification of patients, who may progress to advanced cSCC, emerge as pressing research areas with important implications for cost-efficiency planning and optimisation of patient care.

Cutaneous squamous cell carcinoma in patients with chronic lymphocytic leukemia: a systematic review of the literature

The continuous improvement of life expectancy of patients with chronic lymphocytic leukemia (CLL) has resulted in increased risk of second primary malignancy that potentially may affect survival and quality of life of CLL patients. We performed a systematic review to assess the risk and the clinical‐pathological features and prognosis of cutaneous squamous cell carcinoma (cSCC) in patients with CLL. We searched PubMed, Embase, and Cochrane Central Register of Control Trials databases for articles published from database inception to December 31, 2019. English‐language studies reporting original data on patients with a specific diagnosis of CLL and cSCC were included. Data were extracted using a standardized extraction form, and any discordance was resolved by consensus. Descriptive data were generated by pooling patients from eligible studies. Of the 4588 non‐duplicate records identified, 55 articles met our inclusion criteria. These studies reported that CLL patients have a 3.2% prevalence of cSCC, with an 11.5% cSCC‐related lethality and an overall risk of metastasis of 5.7% (7.3% for regional lymph node involvement and 3.8% for distant metastasis). The quality of evidence was limited by the high heterogeneity in the design, populations, and objectives of the included studies. This systematic review suggests that cSCC in CLL patients tends to behave less aggressively compared with the solid organ transplant recipients but has a higher morbidity and mortality than in the general population. Future prospective studies are needed to increase the quality of evidence and to determine the best treatment modalities and screening intervals for these patients.

Case Report: Combined Intra-Lesional IL-2 and Topical Imiquimod Safely and Effectively Clears Multi-Focal, High Grade Cutaneous Squamous Cell Cancer in a Combined Liver and Kidney Transplant Patient

Cutaneous squamous cell carcinoma (cSCC) is the second most common non-melanoma skin cancer worldwide, with ever increasing incidence and mortality. While most patients can be treated successfully with surgical excision, cryotherapy, or radiation therapy, there exist a subset of patients with aggressive cSCC who lack adequate therapies. Among these patients are solid organ transplant recipients who due to their immunosuppression, develop cSCC at a dramatically increased rate compared to the normal population. The enhanced ability of the tumor to effectively undergo immune escape in these patients leads to more aggressive tumors with a propensity to recur and metastasize. Herein, we present a case of aggressive, multi-focal cSCC in a double organ transplant recipient to frame our discussion and current understanding of the immunobiology of cSCC. We consider factors that contribute to the significantly increased incidence of cSCC in the context of immunosuppression in this patient population. Finally, we briefly review current literature describing experience with localized therapies for cSCC and present a strong argument and rationale for consideration of an IL-2 based intra-lesional treatment strategy for cSCC, particularly in this immunosuppressed patient population.

Parotid metastases of cutaneous squamous cell carcinoma in renal transplant recipients: Case series and literature review

Cutaneous squamous cell skin carcinoma (cSCC) is the most common skin cancer in renal transplant recipients (RTR). Metastatic potential of cSCC is significantly higher in RTR than in the general population. Parotid metastases (PM) of cSCC are rare, but their prognosis is poor. The present study aimed to investigate the frequency and characteristics of PM of cSCC in our renal transplant cohort. Among 1610 patients who received kidney allografts at our institution in the period from January 1999 to December 2019, 84 patients (5.2%) developed at least one cSCC. Three patients were identified to develop PM within 3 to 6 months after the occurrence of primary cSCC. All PM were discovered by clinical examination and in an advanced stage. Two of them died early after the diagnosis of PMs (after 4 months and 1 year, respectively). In conclusion, immunosuppression is one of the major risk factors for the development of cSCC and its metastases. It contributes to the poor survival of patients with PMs of the cSCC. Our experience emphasizes the need for the employment of the radiological tests in patients with primary high-risk cSCC to evaluate nonpalpable lymph node involvement.

Post-transplant malignancies in pediatric organ transplant recipients

The majority of cancer diagnoses in pediatric solid organ transplant recipients (SOTRs) are post-transplantation lymphoproliferative disorders (PTLD) or skin cancers. However, pediatric SOTRs are also at significantly elevated risk for multiple other solid and hematological cancers. The risks of specific cancers vary by transplanted organ, underlying disease, and immunosuppression factors. More than one-quarter of pediatric SOTRs develop cancer within 30 years of transplantation and their risk of solid cancer is 14 times greater than the general population. Pediatric SOTRs are at significantly higher risk of cancer-associated death. Improving patient survival among pediatric SOTRs puts them at risk of adult epithelial cancers associated with environmental carcinogenic exposures. Vaccination against oncogenic viruses and avoidance of excessive immunosuppression may reduce the risk of solid cancers following transplantation. Patient and family education regarding photoprotection is an essential component of skin cancer prevention. There is significant variability in cancer screening recommendations for SOTRs and general population approaches are typically not validated for transplant populations. An individualized approach to cancer screening should be developed based on estimated cancer risk, patient life expectancy, and screening test performance.

Keratinocyte Carcinoma Mortality in the United States as Reported in Death Certificates, 2011-2017

BACKROUND

Keratinocyte carcinoma (KC) mortality is relatively modest and its measures are subject to considerable error. Deaths due to KC have been decreasing through 2000 and were relatively stable until 2010.

OBJECTIVE

To estimate the KC mortality rates (MRs) from 2011 to 2017 in USA based on death certificates.

METHODS

A population-based analysis of Center of Disease Control and Prevention data. Main outcomes and measures were the age-adjusted (US 2000 standard population) MRs.

RESULTS

Overall, KC MRs increased significantly (b = 0.04, p < .01). For the period studied, KC MR was 1.24 per 100,000 persons per year (0.62 for sun-exposed sites, 0.38 for genital and 0.23 for perianal sites). At sun-exposed genital and perianal anatomic sites, KC MRs have been increasing in whites, but not in blacks.

CONCLUSION

There was a 17% decrease in the KC MRs until 2000, followed by an increase of 44% through 2017. The accuracy of KC MRs is uncertain. If indeed the increase in mortality is verified, causes may include an increase in KC incidence, an increase of immunosuppressed populations, and changes in the cause of death documentation.

A multi-center study on safety and efficacy of immune checkpoint inhibitors in cancer patients with kidney transplant

Immune checkpoint inhibitors (ICIs) are widely used for various malignancies. However, their safety and efficacy in patients with a kidney transplant have not been defined. To delineate this, we conducted a multicenter retrospective study of 69 patients with a kidney transplant receiving ICIs between January 2010 and May 2020. For safety, we assessed the incidence, timing, and risk factors of acute graft rejection. For efficacy, objective response rate and overall survival were assessed in cutaneous squamous cell carcinoma and melanoma, the most common cancers in our cohort, and compared with stage-matched 23 patients with squamous cell carcinoma and 14 with melanoma with a kidney transplant not receiving ICIs. Following ICI treatment, 29 out of 69 (42%) patients developed acute rejection, 19 of whom lost their allograft, compared with an acute rejection rate of 5.4% in the non-ICI cohort. Median time from ICI initiation to rejection was 24 days. Factors associated with a lower risk of rejection were mTOR inhibitor use (odds ratio 0.26; 95% confidence interval, 0.09-0.72) and triple-agent immunosuppression (0.67, 0.48-0.92). The objective response ratio was 36.4% and 40% in the squamous cell carcinoma and melanoma subgroups, respectively. In the squamous cell carcinoma subgroup, overall survival was significantly longer in patients treated with ICIs (median overall survival 19.8 months vs. 10.6 months), whereas in the melanoma subgroup, overall survival did not differ between groups. Thus, ICIs were associated with a high risk of rejection in patients with kidney transplants but may lead to improved cancer outcomes. Prospective studies are needed to determine optimal immunosuppression strategies to improve patient outcomes.

Loss of the laminin subunit alpha-3 induces cell invasion and macrophage infiltration in cutaneous squamous cell carcinoma

BACKGROUND

Cutaneous squamous cell carcinoma (cSCC) is a common cancer that invades the dermis through the basement membrane. The role of the basement membrane in poorly differentiated cSCC is not well understood.

OBJECTIVES

To study the effect that loss of the laminin subunit alpha-3 (α3) chain from the tumour microenvironment has on tumour invasion and inflammatory cell recruitment.

METHODS

We examined the role of the basement membrane proteins laminin subunits α3, β3 and γ2 in SCC invasion and inflammatory cell recruitment using immunohistochemistry, short hairpin RNA knockdown, RNA-Seq, mouse xenograft models and patient tumour samples.

RESULTS

Analysis of SCC tumours and cell lines using antibodies specific to laminin chains α3, β3 and γ2 identified a link between poorly differentiated SCC and reduced expression of laminin α3 but not the other laminin subunits investigated. Knockdown of laminin α3 increased tumour invasion both in vitro and in vivo. Western blot and immunohistochemical staining identified increased phosphorylated myosin light chain with loss of laminin α3. Inhibition of ROCK (rho-associated protein kinase) but not Rac1 significantly reduced the invasive potential of laminin α3 knockdown cells. Knockdown of laminin subunits α3 and γ2 increased monocyte recruitment to the tumour microenvironment. However, only the loss of laminin α3 correlated with increased tumour-associated macrophages both in xenografted tumours and in patient tumour samples.

CONCLUSIONS

These data provide evidence that loss of the laminin α3 chain in cSCC has an effect on both the epithelial and immune components of cSCC, resulting in an aggressive tumour microenvironment.

Solid organ transplantation worsens the prognosis of patients with cutaneous squamous cell carcinoma of the head and neck region-Comparison between solid organ transplant recipients and immunocompetent patients

BACKGROUND

Cutaneous squamous cell carcinoma of the head and neck (CSCC-HN) appears to behave more aggressively in immunosuppressed patients. We aimed to investigate this hypothesis by comparing solid organ transplant recipients (SOTR) with CSCC-HN to immunocompetent patients.

METHODS

A retrospective comparative study was conducted for SOTR and immunocompetent patients who were treated for CSCC-HN.

RESULTS

A total of 177 SOTR and 157 immunocompetent patients with CSCC-HN were included. Lymph node metastases were more common in the SOTR group (9% vs 3%), and distant metastases occurred only in SOTR (3% of patients). SOTR had a higher rate of recurrences (19% vs 10%), which were mostly regional (7%) and distant (3%). The 2-year disease-specific survival of SOTR was lower (93% vs 100%).

CONCLUSIONS

SOTR with CSCC-HN has significantly worse outcomes compared to immunocompetent patients. Solid-organ transplantation should be regarded as a negative prognostic factor in patients with CSCC-HN.

Actinic Keratoses: Reconciling the Biology of Field Cancerization with Treatment Paradigms

This Perspective briefly reviews the relationship between UV-induced mutations in habitually sun-exposed human skin and subsequent development of actinic keratoses (AKs) and skin cancers. It argues that field therapy rather than AK-selective therapy is the more logical approach to cancer prevention and hypothesizes that treatment early in the process of field cancerization, even prior to the appearance of AKs, may be more effective in preventing cancer as well as more beneficial for and better tolerated by at-risk individuals. Finally, the Perspective encourages use of rapidly advancing DNA analysis techniques to quantify mutational burden in sun-damaged skin and its reduction by various therapies.

A review of terms used to define cutaneous squamous cell carcinoma with a poor prognosis

Cutaneous squamous cell carcinoma (cSCC) is the second most common cancer in humans and its incidence is both underestimated and on the rise. cSCC is referred to in the literature as high-risk cSCC, locally advanced cSCC, metastatic cSCC, advanced cSCC, and aggressive cSCC. These terms can give rise to confusion and are not always well defined. In this review, we aim to clarify the concepts underlying these terms with a view to standardizing the description of this tumor, something we believe is necessary in light of the new drugs that have been approved or are in development for cSCC.

A paracrine activin A-mDia2 axis promotes squamous carcinogenesis via fibroblast reprogramming

Cancer‐associated fibroblasts (CAFs) are key regulators of tumorigenesis and promising targets for next‐generation therapies. We discovered that cancer cell‐derived activin A reprograms fibroblasts into pro‐tumorigenic CAFs. Mechanistically, this occurs via Smad2‐mediated transcriptional regulation of the formin mDia2, which directly promotes filopodia formation and cell migration. mDia2 also induces expression of CAF marker genes through prevention of p53 nuclear accumulation, resulting in the production of a pro‐tumorigenic matrisome and secretome. The translational relevance of this finding is reflected by activin A overexpression in tumor cells and of mDia2 in the stroma of skin cancer and other malignancies and the correlation of high activin A/mDia2 levels with poor patient survival. Blockade of this signaling axis using inhibitors of activin, activin receptors, or mDia2 suppressed cancer cell malignancy and squamous carcinogenesis in 3D organotypic cultures, ex vivo, and in vivo, providing a rationale for pharmacological inhibition of activin A‐mDia2 signaling in stratified cancer patients.

Outcomes in intermediate-risk squamous cell carcinomas treated with Mohs micrographic surgery compared with wide local excision

BACKGROUND

Brigham and Women's Hospital stage T2a squamous cell carcinomas, demonstrating a single high-risk feature, have a low risk of metastasis and death but an increased risk of local recurrence. Little evidence exists for the best treatment modality and associated outcomes in T2a squamous cell carcinoma.

OBJECTIVE

We aimed to compare outcomes for T2a squamous cell carcinoma treated by Mohs micrographic surgery compared with wide local excision with permanent sections.

METHODS

Retrospective review of an institutional review board-approved single-institution registry of T2a squamous cell carcinoma.

RESULTS

Three hundred sixty-six primary T2a tumors were identified, including 240 squamous cell carcinomas (65.6%) treated with Mohs micrographic surgery and 126 (34.4%) treated with wide local excision. A total of 32.5% of patients were immunosuppressed and mean oncologic follow-up was 2.8 years. Local recurrence was significantly more likely after wide local excision (4.0%) than after Mohs micrographic surgery (1.2%) (P = .03). Multiple logistic regression demonstrated immunocompromised state (odds ratio [OR] 5.1; 95% confidence interval [CI] 1.1-23.3; P = .03) and wide local excision (OR 4.8; 95% CI 1.1-21.6; P = .04) associated with local recurrence; and wide local excision (OR 7.8; 95% CI 2.4-25.4; P < .001), high-risk head and neck location (OR 8.3; 95% CI 1.8-38.7; P = .004), and poor histologic differentiation (OR 4.7; 95% CI 1.4-15.4; P = .03) associated with poor outcomes (overall recurrence or disease-specific death).

CONCLUSION

Mohs micrographic surgery provides improved outcomes in Brigham and Women's Hospital T2a squamous cell carcinoma.

The Role of the Immune System in Cutaneous Squamous Cell Carcinoma

Cutaneous squamous cell carcinoma (cSCC) is the second most common skin cancer. In immunosuppressed populations it is a source of considerable morbidity and mortality due to its enhanced recurrence and metastatic potential. In common with many malignancies, leucocyte populations are both protective against cancer development and also play a role in 'sculpting' the nascent tumor, leading to loss of immunogenicity and tumor progression. UV radiation and chronic viral carriage may represent unique risk factors for cSCC development, and the immune system plays a key role in modulating the response to both. In this review, we discuss the lessons learned from animal and ex vivo human studies of the role of individual leucocyte subpopulations in the development of cutaneous SCC. We then discuss the insights into cSCC immunity gleaned from studies in humans, particularly in populations receiving pharmacological immunosuppression such as transplant recipients. Similar insights in other malignancies have led to exciting and novel immune therapies, which are beginning to emerge into the cSCC clinical arena.