Noninvasive Detection of Skin Cancer by Imprint Desorption Electrospray Ionization Mass Spectrometry Imaging.

We report a technique for the noninvasive detection of skin cancer by imprint desorption electrospray ionization mass spectrometry imaging (DESI-MSI) using a transfer agent that is pressed against the tissue of interest. By noninvasively pressing a tape strip against human skin, metabolites, fatty acids, and lipids on the skin surface are transferred to the tape with little spatial distortion. Running DESI-MSI on the tape strip provides chemical images of the molecules on the skin surface, which are valuable for distinguishing cancer from healthy skin. Chemical components of the tissue imprint on the tape strip and the original basal cell carcinoma (BCC) section from the mass spectra show high consistency. By comparing MS images (about 150-µm resolution) of same molecules from the tape strip and from the BCC section, we confirm that chemical patterns are successfully transferred to the tape stripe. We also used the technique to distinguish cherry angiomas from normal human skin by comparing the molecular patterns from a tape strip. These results demonstrate the potential of the imprint DESI-MSI technique for the noninvasive detection of skin cancers as well as other skin diseases before and during clinical surgery.

Metabolomic profiling and accurate diagnosis of basal cell carcinoma by MALDI imaging and machine learning.

Basal cell carcinoma (BCC), the most common keratinocyte cancer, presents a substantial public health challenge due to its high prevalence. Traditional diagnostic methods, which rely on visual examination and histopathological analysis, do not include metabolomic data. This exploratory study aims to molecularly characterize BCC and diagnose tumour tissue by applying matrix-assisted laser desorption ionization mass spectrometry imaging (MALDI-MSI) and machine learning (ML). BCC tumour development was induced in a mouse model and tissue sections containing BCC (n = 12) were analysed. The study design involved three phases: (i) Model training, (ii) Model validation and (iii) Metabolomic analysis. The ML algorithm was trained on MS data extracted and labelled in accordance with histopathology. An overall classification accuracy of 99.0% was reached for the labelled data. Classification of unlabelled tissue areas aligned with the evaluation of a certified Mohs surgeon for 99.9% of the total tissue area, underscoring the model's high sensitivity and specificity in identifying BCC. Tentative metabolite identifications were assigned to 189 signals of importance for the recognition of BCC, each indicating a potential tumour marker of diagnostic value. These findings demonstrate the potential for MALDI-MSI coupled with ML to characterize the metabolomic profile of BCC and to diagnose tumour tissue with high sensitivity and specificity. Further studies are needed to explore the potential of implementing integrated MS and automated analyses in the clinical setting.

Diagnostic accuracy of autofluorescence-Raman microspectroscopy for surgical margin assessment during Mohs micrographic surgery of basal cell carcinoma.

BACKGROUND: Autofluorescence (AF)-Raman microspectroscopy is a technology that can detect residual basal cell carcinoma (BCC) on the resection margin of fresh, surgically excised tissue specimens. The technology does not require tissue fixation, staining, labelling or sectioning, and provides quantitative diagnosis maps of the surgical margins in 30 min. OBJECTIVES: To determine the accuracy of the AF-Raman instrument in detecting incomplete BCC excisions during Mohs micrographic surgery (MMS), using histology as the reference standard. METHODS: Skin layers from 130 patients undergoing MMS at the Nottingham University Hospitals NHS Trust (September 2022-July 2023) were investigated with the AF-Raman instrument. The layers were measured when fresh, immediately after excision. The AF-Raman results and the intraoperative assessment by Mohs surgeons were compared with a postoperative consensus-derived reference produced by three dermatopathologists. The sensitivity, specificity, and positive and negative predictive values were calculated. The study was registered with ClinicalTrials.gov (NCT03482622). RESULTS: AF-Raman analysis was successfully completed for 125 of 130 layers and, on average, covered 91% of the specimen surface area, with the lowest surface area covered being 87% for the eyelid and the highest being 94% for forehead specimens. The AF-Raman instrument identified positive margins in 24 of 36 BCC-positive cases [67% sensitivity, 95% confidence interval (CI) 49-82] and negative margins in 65 of 89 BCC-negative cases (73% specificity, 95% CI 63-82). Only one of 12 false-negative cases was caused by misclassification by the AF-Raman algorithm. The other 11 false-negatives cases were a result of no valid Raman signal being recorded at the location of the residual BCC due to either occlusion by blood or poor contact between tissue and the cassette window. The intraoperative diagnosis by Mohs surgeons identified positive margins in 31 of 36 BCC-positive cases (86% sensitivity, 95% CI 70-95) and negative margins in 79 of 89 BCC-negative cases (89% specificity, 95% CI 81-95). CONCLUSIONS: The AF-Raman instrument has the potential to provide intraoperative microscopic assessment of surgical margins in BCC surgery. Further improvements are required for tissue processing, to ensure complete coverage of the surgical specimens.

Basal cell carcinoma (BCC) is one of the most common human cancers, occurring mostly on the face and neck. Most BCCs are treated by cutting them out under local anaesthetic. This is routinely done in a hospital by a dermatologist or plastic surgeon. Surgery aims to remove all the cancer leaving the smallest scar possible, but it is often difficult to know how much normal skin to remove. Results from the laboratory often take 1 to 2 weeks to show if the cancer is clear. A technique called 'Mohs' (micrographic surgery) is recommended for these 'high-risk' BCCs. Mohs surgery removes thin layers of skin and investigates them under a microscope while the patient is still in the hospital. This is repeated until all the layers are clear of cancer. Because of the patchy availability of Mohs surgery, many patients with high-risk BCCs are treated by traditional methods that may not be as good as Mohs. We have developed an instrument that scans layers of skin and can quickly detect BCC. The instrument allows surgeons to check each removed skin layer for cancer cells to decide if more layers need to be removed. In this study, the instrument was tested on skin tissue layers from 130 patients who had Mohs surgery at the Nottingham Treatment Centre. The results showed that the instrument can measure skin layers in approximately 30 minutes and identify BCC with a similar accuracy to a Mohs surgeon, but only when the skin layers are prepared properly. With future improvements, the technology might be used to guide Mohs surgery or help surgeons in centres that do not have access to Mohs surgery.

Estimating remaining life expectancy in veterans with basal cell carcinoma using an automated electronic health record scoring system: A retrospective cohort study.

BACKGROUND: Active surveillance may be considered for low-risk basal cell carcinomas (BCCs) in patients with limited life expectancy; however, estimates of life expectancy are not readily available. Veterans Health Administration's Care Assessment Need (CAN) score may address this problem. OBJECTIVE: We examined the CAN score's performance in predicting 1-, 3-, and 5-year mortality in US veterans with BCC. METHODS: This retrospective cohort study used national Veterans Health Administration's electronic medical record data. The CAN score's performance in the prediction of mortality in veterans with BCC was evaluated based on tests of goodness-of-fit, discrimination, and calibration. RESULTS: For 54,744 veterans with BCC treatment encounters between 2013 and 2018, the CAN score performed well in the prediction of mortality based on multiple tests. A threshold CAN score of 90 had a positive predictive value of 55% for 3-year mortality, clinically useful in identifying patients with intermediate-term survival. LIMITATIONS: The study relied upon the combination of diagnosis codes and procedure codes to identify BCC cases. CONCLUSION: The CAN score has the potential to improve the quality of cancer care for veterans by providing clinicians with an estimate of life expectancy and facilitating conversations in cases where active surveillance can be considered.

Photodynamic application in diagnostic procedures and treatment of non-melanoma skin cancers.

OPINION STATEMENT: Skin tumors commonly seen in dermatology are involved in all layers of the skin and appendages. While biopsy of affected skin remains an essential method to confirm diagnosis and to predicate tumor prognosis, it has its limitations. Recently, photodynamic diagnosis (PDD) has demonstrated high sensitivity in detecting affected skin and mucosal tissues, providing valuable guidance for precision surgery to resect skin and mucosal tumors. In this review, we summarized the literatures concerning the applications of PDD in diagnostic process and treatment of skin and mucosal conditions such as actinic keratoses (AK), basal cell carcinoma (BCC), squamous cell carcinoma (SCC), Bowen's disease (BD) and extramammary Paget's disease (EMPD). The findings suggest that PDD holds substantial promise for expanding clinical applications and deserves further research exploration.

Patient-led skin cancer teledermatology without dermoscopy during the COVID-19 pandemic: important lessons for the development of future patient-facing teledermatology and artificial intelligence-assisted -self-diagnosis.

MySkinSelfie is a mobile phone application for skin self-monitoring, enabling secure sharing of patient-captured images with healthcare providers. This retrospective study assessed MySkinSelfie's role in remote skin cancer assessment at two centres for urgent (melanoma and squamous cell carcinoma) and nonurgent skin cancer referrals, investigating the feasibility of using patient-captured images without dermoscopy for remote diagnosis. The total number of lesions using MySkinSelfie was 814, with a mean patient age of 63 years. Remote consultations reduced face-to-face appointments by 90% for basal cell carcinoma and by 63% for referrals on a 2-week waiting list. Diagnostic concordance (consultant vs. histological diagnosis) rates of 72% and 83% were observed for basal cell carcinoma (n = 107) and urgent skin cancers (n = 704), respectively. Challenges included image quality, workflow integration and lack of dermoscopy. Higher sensitivities were observed in recent artificial intelligence algorithms employing dermoscopy. While patient-captured images proved useful during the COVID-19 pandemic, further research is needed to explore the feasibility of widespread patient-led dermoscopy to enable direct patient-to-artificial intelligence diagnostic assessment.

High-throughput lipidomic profiles sampled with electroporation-based biopsy differentiate healthy skin, cutaneous squamous cell carcinoma, and basal cell carcinoma.

BACKGROUND: The incidence rates of cutaneous squamous cell carcinoma (cSCC) and basal cell carcinoma (BCC) skin cancers are rising, while the current diagnostic process is time-consuming. We describe the development of a novel approach to high-throughput sampling of tissue lipids using electroporation-based biopsy, termed e-biopsy. We report on the ability of the e-biopsy technique to harvest large amounts of lipids from human skin samples. MATERIALS AND METHODS: Here, 168 lipids were reliably identified from 12 patients providing a total of 13 samples. The extracted lipids were profiled with ultra-performance liquid chromatography and tandem mass spectrometry (UPLC-MS-MS) providing cSCC, BCC, and healthy skin lipidomic profiles. RESULTS: Comparative analysis identified 27 differentially expressed lipids (p < 0.05). The general profile trend is low diglycerides in both cSCC and BCC, high phospholipids in BCC, and high lyso-phospholipids in cSCC compared to healthy skin tissue samples. CONCLUSION: The results contribute to the growing body of knowledge that can potentially lead to novel insights into these skin cancers and demonstrate the potential of the e-biopsy technique for the analysis of lipidomic profiles of human skin tissues.

Artificial Intelligence in Dermatology: A Systematic Review of Its Applications in Melanoma and Keratinocyte Carcinoma Diagnosis.

BACKGROUND: Limited access to dermatologic care may pose an obstacle to the early detection and intervention of cutaneous malignancies. The role of artificial intelligence (AI) in skin cancer diagnosis may alleviate potential care gaps. OBJECTIVE: The aim of this systematic review was to offer an in-depth exploration of published AI algorithms trained on dermoscopic and macroscopic clinical images for the diagnosis of melanoma, basal cell carcinoma, and cutaneous squamous cell carcinoma (cSCC). METHODS: Adhering to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines, a systematic review was conducted on peer-reviewed articles published between January 1, 2000, and January 26, 2023. RESULTS AND DISCUSSION: Among the 232 studies in this review, the overall accuracy, sensitivity, and specificity of AI for tumor detection averaged 90%, 87%, and 91%, respectively. Model performance improved with time. Despite seemingly impressive performance, the paucity of external validation and limited representation of cSCC and skin of color in the data sets limits the generalizability of the current models. In addition, dermatologists coauthored only 12.9% of all studies included in the review. Moving forward, it is imperative to prioritize robustness in data reporting, inclusivity in data collection, and interdisciplinary collaboration to ensure the development of equitable and effective AI tools.

Removal of Incidental Skin Cancer During Mohs Micrographic Surgery Indicated for a Different Primary Tumor.

BACKGROUND: Mohs surgery is a tissue-sparing, microscopically controlled procedure used to treat biopsy-proven skin cancers. Because Mohs surgery allows for examination of the complete margin of each tissue layer removed, separate cancers can be treated concomitantly when identified. As early detection of skin cancer is beneficial for reducing morbidity, incidental tumors discovered during Mohs surgery are of significant interest. OBJECTIVE: Our objective was to determine the prevalence and characteristics of incidental skin cancers found during Mohs surgery. METHODS: A retrospective chart review of cases seen at University of California, San Diego, from 2014 to 2021 was performed. RESULTS: Of 13,464 Mohs surgery cases, 4.53% ( n = 610) had incidental skin cancers found during removal of the initially identified tumor. Of the 610 cases, 88.4% ( n = 539) had basal cell carcinoma as the primary tumor and either squamous cell carcinoma (SCC) or SCC in situ as the incidental tumor. About 7.87% ( n = 48) had SCC as the primary tumor and basal cell carcinoma as the incidental tumor. All tumors were removed with clear margins and without significant complications. CONCLUSION: Diagnosis of incidental tumors during Mohs surgery enables early detection of skin cancer and circumvents the need for additional surgery, likely resulting in decreased morbidity and improved cost-effectiveness.

Pathophysiology, Histopathology, and Differential Diagnostics of Basal Cell Carcinoma and Cutaneous Squamous Cell Carcinoma-An Update from the Pathologist's Point of View.

Basal cell carcinoma (BCC) and cutaneous squamous cell carcinoma (cSCC) are the most frequently occurring non-melanocytic skin cancers. The objective of our study is to present the pathophysiology of BCC and cSCC and its direct relationship with the histopathological diagnostics and the differential diagnostics of these types of cancer, based on the morphological characteristics, immunohistochemical profile, and genetic alterations. The qualitative study was based on emphasizing the morphological characteristics and immunohistochemistry profiles of BCC and cSCC and the differential diagnostics based on the tissue samples from the Clinical Pathology Department of Mures Clinical County Hospital between 2020 and 2022. We analyzed the histopathological appearances and immunohistochemical profiles of BCC and cSCC in comparison with those of Bowen disease, keratoacanthoma, hyperkeratotic squamous papilloma, metatypical carcinoma, pilomatricoma, trichoblastoma, Merkel cell carcinoma, pleomorphic dermal sarcoma (PDS), and melanoma. Our study showed the importance of the correct histopathological diagnosis, which has a direct impact on the appropriate treatment and outcome for each patient. The study highlighted the histopathological and morphological characteristics of NMSCs and the precursor lesions in HE and the immunohistochemical profile for lesions that may make the differential diagnosis difficult to establish.

Multi-Wavelength Raman Differentiation of Malignant Skin Neoplasms.

Raman microspectroscopy has become an effective method for analyzing the molecular appearance of biomarkers in skin tissue. For the first time, we acquired in vitro Raman spectra of healthy and malignant skin tissues, including basal cell carcinoma (BCC) and squamous cell carcinoma (SCC), at 532 and 785 nm laser excitation wavelengths in the wavenumber ranges of 900-1800 cm-1 and 2800-3100 cm-1 and analyzed them to find spectral features for differentiation between the three classes of the samples. The intensity ratios of the bands at 1268, 1336, and 1445 cm-1 appeared to be the most reliable criteria for the three-class differentiation at 532 nm excitation, whereas the bands from the higher wavenumber region (2850, 2880, and 2930 cm-1) were a robust measure of the increased protein/lipid ratio in the tumors at both excitation wavelengths. Selecting ratios of the three bands from the merged (532 + 785) dataset made it possible to increase the accuracy to 87% for the three classes and reach the specificities for BCC + SCC equal to 87% and 81% for the sensitivities of 95% and 99%, respectively. Development of multi-wavelength excitation Raman spectroscopic techniques provides a versatile non-invasive tool for research of the processes in malignant skin tumors, as well as other forms of cancer.

[Chinese guildeline on diagnosis and treatment of basal cell carcinoma (2023 edition)].

Basal cell carcinoma (BCC) is the most common skin malignancy, with a higher prevalence in Caucasians than in East Asians. Although there is a lack of epidemiological data in China, it is generally believed that the incidence of BCC in China is increasing due to the aging population. A variety of risk factors are related to the occurrence of BCC, among which ultraviolet rays and gene mutations play a major role, especially the abnormal activation of Hedgehog (Hh) signaling pathway, which is considered to be the most important pathogenesis of BCC. The clinical manifestations of BCC are highly specific, and most experienced doctors can make a preliminary diagnosis by clinical manifestations. Dermoscopy and other imaging methods can greatly improve the accuracy of diagnosis, but there are still some atypical or rare types of BCC that need further confirmation through histopathological examination. This guideline is initiated by the National Clinical Research Center for Skin and Immune Diseases (based on Peking University First Hospital). It has invited a panel of experts consisting of 24 senior dermatologists specializing in dermatologic surgery from the Dermatologic Surgery Group of the Chinese Medical Doctor Association of Dermatology, the Dermatologic Surgery Group of the Dermatology & Venereology Committee, Chinese Association of Integration Medicine, and the Dermatologic Surgery and Cosmetic Branch of Clina Leprosy Association. In addition, experts from the Burn and Plastic Surgery (Maxillofacial), Ophthalmology, Otolaryngology, Head and Neck Surgery, Radiation Therapy, and Pathology were also invited to participate. This panel forms the "Chinese Guideline for the Diagnosis and Treatment of Basal Cell Carcinoma" expert group. Based on the latest domestic and international research findings, the guideline was developed through four rounds of discussions by the expert group and revised to provide valuable references for clinical healthcare providers in the diagnosis and treatment of BCC.

Clinical and Dermoscopic Patterns of Basal Cell Carcinoma and Its Mimickers in Skin of Color: A Practical Summary.

The diagnosis of basal cell carcinoma (BCC) in dark phototypes can be a challenging task due to the lack of relevant clues and its variable presentation. In this regard, there is growing evidence that dermoscopy may benefit the recognition of BCC even for skin of color (SoC). The objective of this review is to provide an up-to-date overview on clinical and dermoscopic patterns of BCC in SoC, also comparing such findings with those of the main clinical mimickers reported in the literature. A comprehensive search of the literature through the PubMed electronic database was carried out in order to identify papers describing the clinical and dermoscopic features of BCC in dark phototypes (IV-VI). By finding macroscopic clinical presentations of BCCs in SoC patients and any possible clinical mimickers considered in the retrieved papers, we built a differential diagnosis list and analyzed the dermoscopic findings of such conditions to facilitate the diagnosis of BCC. BCC in darker skin may present as pigmented nodular lesions, pigmented patches or plaques, ulcers, erythematous nodular lesions, erythematous plaques or patches, or scar-like lesions, depending on its subtype and body site. The differential diagnosis for BCC in patients with SoC includes squamous cell carcinoma, melanoma, nevi, adnexal tumors and sebaceous keratosis. Additionally, it differs from that of Caucasians, as it also includes lesions less common in fair skin, such as dermatosis papulosa nigra, melanotrichoblastoma, and pigmented dermatofibrosarcoma protuberans, and excludes conditions like actinic keratosis and keratoacanthoma, which rarely appear in darker skin. The resulting differences also include infectious diseases such as deep cutaneous mycosis and inflammatory dermatoses. The most prevalent differentiating dermoscopic feature for BCC includes blue, black and gray dots, though arborizing vessels still remain the predominant BCC feature, even in dark phototypes. Diagnostic approach to BCC in dark-skinned patients varies due to the prevalence of dermoscopy findings associated with hyperpigmented structures. Clinicians should be aware of such points of differentiation for a proper management of this tumor in SoC.

[To assess the effectiveness of treatment methods for patients of different age groups with basal cell cancer of the skin of the nose and ears].

The relevance of the problems of diagnosis and treatment of skin cancer is currently determined not only by the high incidence rate, but by the existing difficulties in differential diagnosis and treatment with traditional methods. For localizations of basal cell skin cancer (BCSC) that are "inconvenient" for treatment, such as the external auditory canal, auricle, and wing of the nose, treatment is associated with certain difficulties and the possible appearance of a cosmetic defect, therefore, when choosing a treatment method, the anatomical features of these organs are taken into account. It has been determined that the effectiveness of treatment for primary BCSC of the nose and auricles is higher than recurrent one, and among the various treatment methods, the most effective and radical is the surgical method. The immediate results of treatment of BCSC in the form of PR by surgical method were 86.7%, which is statistically significant compared with other types of treatment (p < 0.05). Long-term treatment results with the surgical method are also higher (77%) compared to other methods, which is also statistically significant (p < 0.05).

Basal Cell Skin Cancer, Version 2.2024, NCCN Clinical Practice Guidelines in Oncology.

Basal cell carcinoma (BCC) is the most common form of skin cancer in the United States. Due to the high frequency, BCC occurrences are not typically recorded, and annual rates of incidence can only be estimated. Current estimated rates are 2 million Americans affected annually, and this continues to rise. Exposure to radiation, from either sunlight or previous medical therapy, is a key player in BCC development. BCC is not as aggressive as other skin cancers because it is less likely to metastasize. However, surgery and radiation are prevalent treatment options, therefore disfigurement and limitation of function are significant considerations. The NCCN Clinical Practice Guidelines in Oncology (NCCN Guidelines) outline an updated risk stratification and treatment options available for BCC.

Real-time, in vivo skin cancer triage by laser-induced plasma spectroscopy combined with a deep learning-based diagnostic algorithm.

BACKGROUND: Although various skin cancer detection devices have been proposed, most of them are not used owing to their insufficient diagnostic accuracies. Laser-induced plasma spectroscopy (LIPS) can noninvasively extract biochemical information of skin lesions using an ultrashort pulsed laser. OBJECTIVE: To investigate the diagnostic accuracy and safety of real-time noninvasive in vivo skin cancer diagnostics utilizing nondiscrete molecular LIPS combined with a deep neural network (DNN)-based diagnostic algorithm. METHODS: In vivo LIPS spectra were acquired from 296 skin cancers (186 basal cell carcinomas, 96 squamous cell carcinomas, and 14 melanomas) and 316 benign lesions in a multisite clinical study. The diagnostic performance was validated using 10-fold cross-validations. RESULTS: The sensitivity and specificity for differentiating skin cancers from benign lesions using LIPS and the DNN-based algorithm were 94.6% (95% CI: 92.0%-97.2%) and 88.9% (95% CI: 85.5%-92.4%), respectively. No adverse events, including macroscopic or microscopic visible marks or pigmentation due to laser irradiation, were observed. LIMITATIONS: The diagnostic performance was evaluated using a limited data set. More extensive clinical studies are needed to validate these results. CONCLUSIONS: This LIPS system with a DNN-based diagnostic algorithm is a promising tool to distinguish skin cancers from benign lesions with high diagnostic accuracy in real clinical settings.

Factors associated with suspected nonmelanoma skin cancers, dysplastic nevus, and cutaneous melanoma among first-time SpotMe screening program participants during 2009-2010.

BACKGROUND: There have been no studies of the American Academy of Dermatology's SpotMe skin cancer screening program to collectively analyze and determine the factors associated with suspected basal cell carcinoma (BCC), squamous cell carcinoma (SCC), dysplastic nevus (DN), and cutaneous melanoma (CM) diagnoses. OBJECTIVE: Describe the demographics, risk factors, and access to care profiles associated with suspected diagnoses of BCC, SCC, DN, and CM among first-time SpotMe screenees during 2009-2010. METHODS: We conducted a cross-sectional analysis of data from the SpotMe skin cancer screenings conducted in 2009 and 2010. We performed multivariable logistic regression analysis for each diagnosis, incorporating standard demographic, access to care, and risk factor variables in the models. RESULTS: Men, those without a regular dermatologist, persons reporting recently changing moles, and those with a personal history of melanoma were at increased risk for each of the suspected diagnoses analyzed. Uninsured persons were at increased risk for suspected malignancies (BCC, SCC, and CM). LIMITATIONS: Lack of histologic confirmation for diagnoses and cross-sectional design. CONCLUSION: Among first-time SpotMe participants, suspected diagnoses of BCC, SCC, DN, and CM shared several associated factors, which may be considered when planning outreach and screening for populations at risk for skin cancer.

"Your Skin Tells You" Campaign for Keratinocyte Cancers: When Individuals' Selection Makes the Difference.

BACKGROUND: Prevention campaigns for skin cancers have focused primarily on melanoma, and over time there has been increasing awareness of the need to select the population to be screened to maximize program effectiveness. OBJECTIVES: The objective of the study was to report the results of a free dermatological initiative, as part of an awareness campaign dedicated to keratinocyte cancers, targeting individuals pre-selected through a short questionnaire. METHODS: One day of dermatological consultations was held at 15 dermato-oncology referral centers during May 22-June 30, 2021. For selection, individuals answered a telephone interview consisting of 7 yes/no questions on risk factors. Demographics, clinical characteristics of suspicious tumors, and histopathologic diagnosis of excised lesions were collected. Suspicion rate, detection rate, and positive predictive values (PPVs) for any skin cancer, basal cell carcinoma (BCC), cutaneous squamous cell carcinoma (cSCC), and melanoma were calculated. RESULTS: A total of 320 individuals (56.9% males; 43.1% females) with a median age of 69.6 (range 21-91) years qualified for the screening initiative. Overall, skin cancers and precancerous lesions were diagnosed in 65.9% of the patients. Suspicion rate was 28.7% for any skin cancer (92/320), 22.8% for BCC (73/320), 4.7% for cSCC (15/320), and 1.2% for melanoma (4/320). Detection rate was 23.4% for any skin cancer (PPV 93.7%), 18.1% for BCC (PPV 95.1%), 4.4% for cSCC (PPV 93.3%), and 0.9% for melanoma (PPV 75%). CONCLUSIONS: Selection of individuals at high risk is a cost-effective approach for early detection campaigns for keratinocyte cancers.

Skin Cancer Development Is Strongly Associated with Actinic Keratosis in Solid Organ Transplant Recipients: A Danish Cohort Study.

BACKGROUND AND OBJECTIVES: Solid organ transplant recipients (SOTRs) are at increased risk of skin cancer and suffer from greater disease-specific morbidity and mortality. To risk stratify the expanding SOTR population for more targeted skin cancer screening, a detailed understanding of risk factors is needed. Using combined clinical and pathological data to capture prevalence of actinic keratosis (AK) and skin cancer, this study aimed to identify risk factors of skin cancer development in a Danish SOTR cohort. METHODS: The trial comprised a retrospective cohort study of patients attending organ transplant clinics at the dermatological departments of Bispebjerg and Gentofte Hospitals in Copenhagen, Denmark, between 2009 and 2021. In addition to pathology records, AK prevalence was determined by review of electronic medical records (EMRs) of SOTR visits which specifically included descriptions of clinical AK. Prevalence of skin cancer, here defined as basal cell carcinoma (BCC), squamous cell carcinoma (SCC) (invasive or in situ), or melanoma (invasive or in situ), was determined by EMR and pathology code review. Additional data extracted from EMRs included age, sex, Fitzpatrick skin type, transplantation date and type, and immunosuppressive therapy. The effect of risk factors on skin cancer was calculated by Cox proportional hazards regression. RESULTS: A total of 822 SOTRs were included with a mean follow-up duration of 10.8 years (SD 2.4 years). A skin dysplasia diagnosis was identified in 30% (n = 250) of the population, consisting of either AK (22%; n = 177), skin cancer (23%; n = 186) or both (14%; n = 113). An AK diagnosis predicted both SCC (odds ratio [OR]: 31.5 [95% CI: 9.8-100.6], p < 0.0001) and BCC development (OR: 2.3 [95% CI: 1.6-3.3], p < 0.0001), with AKs diagnosed an average 3.1 years before the first SCC (p < 0.0001). Correspondingly, while the risk of SCC in SOTRs without AK was 1.4% 25 years after transplantation, SOTRs with AKs had a 23% SCC risk only 10 years posttransplant. Other identified risk factors included Fitzpatrick skin type I (BCC: OR: 2.4 [95% CI: 1.2-5.0], p = 0.018; SCC: 3.2 [95% CI: 1.2-8.2], p = 0.016) and transplantation duration >15 years (BCC: OR: 1.8 [95% CI: 1.2-2.7], p = 0.007). No significant association between skin cancer development and sex or immunosuppressive regimen was shown. CONCLUSION: Keratinocyte carcinoma is strongly associated with an AK diagnosis in SOTRS and should prompt intensified skin cancer screening in affected individuals.

Pagetoid Spread in Basal Cell Carcinoma: Potential for Misdiagnosis.

ABSTRACT: Basal cell carcinomas are one of the most common cutaneous carcinomas and show classical histologic features of basaloid nests with peripheral palisading. Pagetoid and intraepidermal spread has not been described in basal cell carcinoma to the best of our knowledge. We report 5 cases of basal cell carcinoma with classic histologic patterns and overlying basaloid nests and single intraepidermal tumor cells. A panel of immunostains were performed that included CK7, MOC31, CEA-m, EMA, androgen receptor, and Bcl2. Most of our cases were positive for both MOC31 and CK7, and all cases were negative for CEA-m and EMA excluding extramammary Paget disease, one of the most common differential diagnoses. These cases expand the spectrum of findings that can be seen in basal cell carcinoma and can help prevent misdiagnoses of basal cell carcinomas as more aggressive tumors.