Non-melanoma Skin Cancer Lesions Research Articles

Color Analysis of Merkel Cell Carcinoma: A Comparative Study with Cherry Angiomas, Hemangiomas, Basal Cell Carcinomas, and Squamous Cell Carcinomas.

Merkel cell carcinoma (MCC) is recognized as one of the most malignant skin tumors. Its rarity might explain the limited exploration of digital color studies in this area. The objective of this study was to delineate color alterations in MCCs compared to benign lesions resembling MCC, such as cherry angiomas and hemangiomas, along with other non-melanoma skin cancer lesions like basal cell carcinoma (BCC) and squamous cell carcinoma (SCC), utilizing computer-aided digital color analysis. This was a retrospective study where clinical images of the color of the lesion and adjacent normal skin from 11 patients with primary MCC, 11 patients with cherry angiomas, 12 patients with hemangiomas, and 12 patients with BCC/SCC (totaling 46 patients) were analyzed using the RGB (red, green, and blue) and the CIE Lab color system. The Lab color system aided in estimating the Individual Typology Angle (ITA) change in the skin, and these results are documented in this study. It was demonstrated that the estimation of color components can assist in the differential diagnosis of these types of lesions because there were significant differences in color parameters between MCC and other categories of skin lesions such as hemangiomas, common skin carcinomas, and cherry hemangiomas. Significant differences in values were observed in the blue color of RGB (p = 0.003) and the b* parameter of Lab color (p < 0.0001) of MCC versus cherry angiomas. Similarly, the mean a* value of Merkel cell carcinoma (MCC) compared to basal cell carcinoma and squamous cell carcinoma showed a statistically significant difference (p < 0.0001). Larger prospective studies are warranted to further validate the clinical application of these findings.

P63 Effectiveness of an image-analysing artificial intelligence-based digital health technology to diagnose nonmelanoma skin cancer and benign skin lesions

Abstract Squamous cell carcinoma (SCC) and basal cell carcinoma (BCC) are common types of nonmelanoma skin cancer (NMSC). The DERM-003 study was a prospective, multicentre, single-arm, masked study that aimed to demonstrate the effectiveness of an artificial intelligence-based digital health technology (AI-DHT) to identify SCC, BCC and premalignant conditions in dermoscopic images of suspicious skin lesions. Patients with at least one suspicious skin lesion that was suitable for photography were eligible. Each lesion was photographed with three smartphone cameras (iPhone 6S, iPhone 11 and Samsung 10) with a dermoscopic lens attached. Each image was assessed by the AI-DHT. A clinical diagnosis was made by the dermatologist, and histopathology results were obtained for biopsied lesions. The AI-DHT output was compared with the histopathology diagnosis, and the area under the receiver operating characteristic curve (AUROC) was calculated. Secondary endpoints included other diagnostic measures and assessment of premalignant lesions. Altogether, 572 patients (49.5% female, mean age 68.5 years, 96.9% Fitzpatrick skin types I–III) were recruited from four UK National Health Service trusts, providing images of 611 suspicious lesions. There were no exclusion criteria relating to skin type. In total, 592 lesions had images from all three cameras available; only one lesion had no images available. Altogether, 395 lesions had a histopathology result. Forty-seven biopsied lesions were diagnosed as SCC and 184 as BCC. The AUROCs for images taken by the iPhone 6S were 0.88 [95% confidence interval (CI) 0.83–0.93] for SCC and 0.87 (95% CI 0.84–0.91) for BCC. For Samsung 10, the AUROCs were 0.85 (95% CI 0.79–0.90) and 0.87 (95% CI 0.83–0.90), and for iPhone 11, they were 0.88 (95% CI 0.84–0.93) and 0.89 (95% CI 0.86–0.92) for SCC and BCC, respectively. Using images taken on iPhone 6S of biopsied-only lesions, the sensitivity rates in detecting SCC and BCC were 98% (95% CI 88–100) and 94% (95% CI 90–97), respectively; the specificity rates were 38% (95% CI 33–44) and 28% (95% CI 21–35), respectively; the positive predictive values were 17% (95% CI 16–19) and 59% (95% CI 56–61), respectively; and the NPVs were 99% (95% CI 95–100) and 81% (95% CI 70–89), respectively. All 12 lesions diagnosed as Bowen disease were classified correctly by the AI-DHT. Of the 61 lesions diagnosed as actinic keratosis, 52 were correctly classified of the 22 lesions diagnosed as dysplastic and 18 were correctly classified by the AI-DHT. All 16 lesions diagnosed as melanoma were classified as such by the AI-DHT. The AI-DHT has the potential to support the diagnosis of NMSC and premalignant lesions.

BT03 (P63) Effectiveness of an image-analysing artificial intelligence-based digital health technology to diagnose nonmelanoma skin cancer and benign skin lesions

Abstract Squamous cell carcinoma (SCC) and basal cell carcinoma (BCC) are common types of nonmelanoma skin cancer (NMSC). The DERM-003 study was a prospective multicentre single-arm masked study that aimed to demonstrate the effectiveness of an artificial intelligence-based digital health technology (AI-DHT) to identify SCC, BCC and premalignant conditions in dermoscopic images of suspicious skin lesions. Patients with at least one suspicious skin lesion that was suitable for photography were eligible. Each lesion was photographed with three smartphone cameras (iPhone 6S, iPhone 11 and Samsung 10) with a dermoscopic lens attached. Each image was assessed by the AI-DHT. A clinical diagnosis was made by the dermatologist, and histopathology results were obtained for biopsied lesions. The AI-DHT output was compared with the histopathology diagnosis, and the area under the receiver operating characteristic curve (AUROC) was calculated. Secondary endpoints included other diagnostic measures and assessment of premalignant lesions. Altogether, 572 patients (49.5% women, mean age 68.5 years, 96.9% Fitzpatrick skin types I–III) were recruited from four UK National Health Service trusts, providing images of 611 suspicious lesions. There were no exclusion criteria relating to skin type. In total, 592 lesions had images from all three cameras available; only one lesion had no images available. Altogether, 395 lesions had a histopathology result. Forty-seven biopsied lesions were diagnosed as SCC and 184 as BCC. The AUROCs for images taken by the iPhone 6S was 0.88 [95% confidence interval (CI) 0.83–0.93] for SCC and 0.87 (95% CI 0.84–0.91) for BCC. For the Samsung 10, the AUROCs were 0.85 (95% CI 0.79–0.90) and 0.87 (95% CI 0.83–0.90), and for the iPhone 11, they were 0.88 (95% CI 0.84–0.93) and 0.89 (95% CI 0.86–0.92) for SCC and BCC, respectively. Using images taken on the iPhone 6S of biopsied only lesions, the sensitivity in detecting SCC and BCC was 98% (95% CI 88–100) and 94% (95% CI 90–97), respectively; the specificity was 38% (95% CI 33–44) and 28% (95% CI 21–35), respectively; the positive predictive value was 17% (95% CI 16–19) and 59% (95% CI 56–61), respectively; and the NPV was 99% (95% CI 95–100) and 81% (95% CI 70–89), respectively. All 12 lesions diagnosed as Bowen disease were classified correctly by the AI-DHT. Of the 61 lesions diagnosed as actinic keratosis, 52 were correctly classified of the 22 lesions diagnosed as dysplastic, and 18 were correctly classified by the AI-DHT. All 16 lesions diagnosed as melanoma were classified as such by the AI-DHT. The AI-DHT has the potential to support the diagnosis of NMSC and premalignant lesions.

Analysis of image-guided superficial radiation therapy (IGSRT) on the treatment of early-stage non-melanoma skin cancer (NMSC) in the outpatient dermatology setting

BackgroundInterest in image-guidance superficial radiation therapy (IGSRT) for the treatment of early-stage non-melanoma skin cancer (NMSC) has resurfaced given its low complication rates, superior cosmesis and local control and cure rates. In addition, it has been recommended by the American Academy of Dermatology (AAD) for early-stage NMSC in patients who are considered poor surgical candidates.Methods1899 NMSC lesions were treated with energies ranging from 50 to 100 kilovoltage (kV), for a mean of 20.2 fractions, and treatment dose of 5364.4 centigray (cGy). Lesions were treated for a mean of 7.5 weeks and followed for 65.5 weeks. SAS studio was used to conduct Kaplan–Meier analysis to calculate local control rates and account for differences in follow-up intervals. A log-rank test was used to calculate statistical differences between histologies.ResultsAbsolute lesion control was achieved in 99.7% of the patients after an average of 7.5 weeks of treatment, with a stable control rate of 99.6% when the follow-up duration was over 12 months. 95% of lesions with toxicity scoring received a Radiation Treatment Oncology Group Toxicity (RTOG) score of 1 or 2.ConclusionIGSRT has a high safety profile, can achieve superior cosmesis and should be considered first-line for treating early-stage NMSC tumors as cure rates have been shown to be effective in all NMSC on early follow-up.

Multilayer intensity modulated contact interventional radiotherapy (brachytherapy): Stretching the therapeutic window in skin cancer.

Interventional radiotherapy (IRT, brachytherapy) is a highly effective treatment method for non-melanoma skin cancer (NMSC). Traditionally, the maximum depth of NMSC lesions considered eligible for contact IRT was 5 mm; however, following several national surveys and recent recommendations, such cut-off, lesions thicker than 5 mm may be treated by contact IRT. The use of image guidance in defining the actual depth in treating NMSC to correctly identify clinical target volume (CTV) and prevent unnecessary toxicity is of paramount importance. The aim of the paper was to describe a multilayer arrangement of catheters to treat NMSC lesions thicker than 5 mm, thus proposing an example of dynamic intensity modulated IRT, using different catheter-to-skin distance of sources to reach the best CTV coverage and maximally reduce the excess of dose to the skin.

Prognostic factors and the role of adjuvant radiation therapy in Non-melanoma skin cancer: Retrospective, A single-center experience

Objective: Non-melanoma skin cancer (NMSC) is the most prevalent malignancy worldwide, with basal cell carcinoma (BCC) and squamous cell carcinoma (SCC) representing the most common types of NMSC. In this retrospective analysis, patients with NMSC who had adjuvant radiotherapy (RT) had their treatment results and prognostic variables evaluated. Material and Methods: A total of 115 patients with NMSC who had adjuvant RT in our clinic during January 2006 and September 2021 were assessed. The average age was 74 years, and the male to female ratio was 1.95:1. (range: 25–95). The most often diagnosed kind of NMSC was SCC (93%, n=107), preceded by BCC (7%, n=8). The extremities (17.4%, n=20), the trunk (1.7%, n=2), and the head and neck area (80.9%, n=93) were where the bulk of NMSC lesions were discovered. Results: The mean follow-up period was 60.7 months (the range was 4.2–194.7); metastases were found in six patients (5.2%), and locoregional recurrence was identified in 24 patients (20.8%). The 3- and 5-year total survival percentages were 71.2% and 59.3%, respectively, and the median overall survival (OS) time was 87.1 months. Tumor size and surgical margin status were linked to a worse OS in multivariate analysis of prognostic variables (hazard rate [HR]=3.0, 95% confidence interval [CI]: 1.8-5.2; p=0,001 and HR=2.4, 95% CI: 1.4-4.1; P=0,002, respectively). Conclusion: Postoperative RT is an efficient, acceptable therapeutic option for NMSC in high-risk individuals. Our results suggest that surgical margin and tumor size were independent predictors of OS in NMSC patients; nevertheless, future studies including more patients are required to corroborate these results.

Validation of an individualized home-made superficial brachytherapy mold applied for deep nonmelanoma skin cancer.

This study was conducted to evaluate the effect of brachytherapy (BT) customized mold [Condensation silicone elastomer (ProtesilTM)] and its thickness on the dose distribution pattern of deep nonmelanoma skin cancers (NMSC). Four blocks of mold material were constructed in 5, 10, 15, and 20 mm thickness and 100 × 100 mm2 area by a plastic cast. The high dose rate (HDR) plus treatment planning system (TPS) (Version 3, Eckert & Ziegler BEBIG Gmbh, Berlin, Germany) with a 60Co source (model: Co0.A86, EZAG BEBIG, Berlin, Germany) as an high dose rate brachytherapy (HDR-BT) source was used. Solid phantom and MOSFETTM and GAFCHROMICTM EBT3 film dosimeters were used for experimental dosimetry of the different thicknesses (up to 20 mm) of BT customized mold. Skin dose and dose to different depths were evaluated. The TPS overestimated the calculated dose to the surface. Skin dose can be reduced from 250% to 150% of the prescription dose by increasing mold thickness from 5 mm to 20 mm. There was a 7.7% difference in the calculated dose by TPS and the measured dose by MOSFET. There was a good agreement between film dosimetry, MOSFET detector, and TPS' results in depths less than 5 mm. Each BT department should validate any individualized material chosen to construct the customized surface BT mold. Increasing the mold thickness can treat lesions without overexposing the skin surface. Superficial BT can be recommended as an appropriate treatment option for some deep NMSC lesions (up to 20 mm) with pre-planning considerations employing thicker molds.

Laminated holmium-166-containing electrospun bandages for use against skin cancer

The number of non-melanoma skin cancer (NMSC) cases in the US will increase significantly over the next decade due to a rise in UV exposure. One of the treatment methods used to remove NMSC lesions is radiation therapy. The two types of radiation therapy used in the clinic are external beam therapy and brachytherapy. However, both require specialized on-site instrumentation and for patients to remain immobile. In this work, we studied an alternative radiation therapy – one that does not require expensive on-site equipment and would allow for enhanced patient mobility and, thus, comfort. We prepared sealed source, nylon-laminated holmium-166-containing radiotherapeutic bandages and used them in C3H/HeN mice with murine SCCVII tumor grafts. Overall, tumor sizes were smallest when treated with therapeutically relevant radiation doses via radiotherapeutic bandages (compared to controls), and no histological evidence of toxicity to tissues was observed. Thus, our optimized radiotherapeutic bandage offers a flexible approach to treating NMSC.

A Novel Approach for the Shape Characterisation of Non-Melanoma Skin Lesions Using Elliptic Fourier Analyses and Clinical Images.

The early detection of Non-Melanoma Skin Cancer (NMSC) is crucial to achieve the best treatment outcomes. Shape is considered one of the main parameters taken for the detection of some types of skin cancer such as melanoma. For NMSC, the importance of shape as a visual detection parameter is not well-studied. A dataset of 993 standard camera images containing different types of NMSC and benign skin lesions was analysed. For each image, the lesion boundaries were extracted. After an alignment and scaling, Elliptic Fourier Analysis (EFA) coefficients were calculated for the boundary of each lesion. The asymmetry of lesions was also calculated. Then, multivariate statistics were employed for dimensionality reduction and finally computational learning classification was employed to evaluate the separability of the classes. The separation between malignant and benign samples was successful in most cases. The best-performing approach was the combination of EFA coefficients and asymmetry. The combination of EFA and asymmetry resulted in a balanced accuracy of 0.786 and an Area Under Curve of 0.735. The combination of EFA and asymmetry for lesion classification resulted in notable success rates when distinguishing between benign and malignant lesions. In light of these results, skin lesions’ shape should be integrated as a fundamental part of future detection techniques in clinical screening.

218 Updated results of 3,050 lesions in 1725 patients treated with novel technology using image guided superficial radiotherapy (IGSRT), a multi-institutional study

Image-guided superficial radiation therapy (IGSRT) is becoming an attractive non-surgical curative treatment option for nonmelanoma skin cancer (NMSC). We previously reported IGSRT treatment results from a multi-institutional study of 1632 patients with 2917 NMSC lesions (Yu et al. Oncol Ther 2021, https://doi.org/10.1007/s40487-021-00138-4) showing excellent local control(LC) of 99.3% with mean follow-up(f/u) of 69.8 weeks. This abstract analyzes an additional 93 patients, updates previous findings with longer f/u, and performs subgroup analysis.

Incidence of Non-Melanoma Skin Cancers in Patients with Chronic Lymphocytic Leukaemia: A Retrospective Study in a Bay of Plenty, New Zealand Population

Background/Aims: Chronic lymphocytic leukaemia (CLL) incurs an increased risk of developing second primary malignancies (SPMs). The pathogenesis underpinning this increased SPM risk is attributable to synergism between genetic aberrations, chronic immune suppression / dysfunction and CLL treatments. Specifically, CLL associated skin cancer is a well-documented phenomenon, with common malignancies such as squamous (SCC) and basal cell (BCC) carcinomas occurring at higher frequencies in CLL patients and are often of a more aggressive phenotype. The incidence of non-melanoma skin cancers (NMSCs) among New Zealand CLL patients is unknown, as NMSCs are not required to be reported to the New Zealand Cancer Registry. Accordingly, this study aimed to analyse the incidence of NMSC in CLL patients from the Bay of Plenty region of New Zealand.Methods: We conducted a retrospective analysis of 213 CLL patients, who were referred to Bay of Plenty District Health Board (BOPDHB) between 2015 and 2020, for the occurrence of SPMs. Clinical notes were reviewed for the demographics of sex, age at time of CLL diagnosis, CLL treatments received and occurrence and type of NMSCs. A control group of 76 patients referred to BOPDHB haematology, for anaemia or thrombocytopenia, of which the cause subsequently remained unknown and was not associated with lymphoproliferative disease, was reviewed for primary malignancy (PM), occurrence and type. NMSC incidence was also compared to a local data, on overall NMSC incidence in the general Bay of Plenty population, in 2015.Results: The predominant SPM types occurring in this CLL patient group were NMSCs. A total of 249 and 170 histological diagnoses of SCC and BCC were made in our group of CLL patients, respectively. Of the 213 CLL patients, 48.8% had a diagnosis of at least one NMSC, with median time between CLL and NMSC diagnosis of 5 years (range, -6 to 19 years). CLL patients that were diagnosed with NMSC developed a mean number of 3.93 ± 2.94 separate lesions, compared to 2.6 ± 1.7 lesions in our control population. Note: comparison of NMSC incidence data between CLL group and Bay of Plenty populationConclusion: Patients with CLL are at increased risk of developing multiple NMSC lesions. Therefore, we believe CLL patients should be assessed by dermatologists or general practitioners for whole-body skin examination, 6 monthly following their CLL diagnosis. This strategy promotes early diagnosis, and patient education on importance of sun protection strategies to reduce NMSC risk. This is essential to the ongoing care of CLL patients in a NZ context, given the increased incidence of NMSC associated with CLL, in combination with the high levels of UV exposure and skin damage among the NZ general population. This study also highlights how NMSC disease burden is likely to be significantly underestimated due to a lack of data collection on these malignancies by the New Zealand Cancer Registry. DisclosuresNo relevant conflicts of interest to declare.

Characterization of Mueller matrix elements for classifying human skin cancer utilizing random forest algorithm.

.Significance: The Mueller matrix decomposition method is widely used for the analysis of biological samples. However, its presumed sequential appearance of the basic optical effects (e.g., dichroism, retardance, and depolarization) limits its accuracy and application.Aim: An approach is proposed for detecting and classifying human melanoma and non-melanoma skin cancer lesions based on the characteristics of the Mueller matrix elements and a random forest (RF) algorithm.Approach: In the proposal technique, 669 data points corresponding to the 16 elements of the Mueller matrices obtained from 32 tissue samples with squamous cell carcinoma (SCC), basal cell carcinoma (BCC), melanoma, and normal features are input into an RF classifier as predictors.Results: The results show that the proposed model yields an average precision of 93%. Furthermore, the classification results show that for biological tissues, the circular polarization properties (i.e., elements , , , and of the Mueller matrix) dominate the linear polarization properties (i.e., elements , , , and of the Mueller matrix) in determining the classification outcome of the trained classifier.Conclusions: Overall, our study provides a simple, accurate, and cost-effective solution for developing a technique for classification and diagnosis of human skin cancer.

Serial Excision for Treatment of Non-melanoma Skin Cancer.

Background:Mohs micrographic surgery (MMS) has become the predominant modality of excision for non-melanoma skin cancers (NMSC). Patients are referred for MMS under the assumption that it is the most effective procedure for definitive removal of the cancer while also allowing for maximal tissue preservation to achieve optimal cosmesis. The objective of this study was to investigate outcomes of serial excision (SE) as an alternative excision modality for NMSC.Methods:Patients undergoing SE for basal cell carcinoma or squamous cell carcinoma by the senior author from 2009 to 2020 were retrospectively reviewed. Patient demographics, lesion characteristics, and excision characteristics were recorded. The primary outcome was the number of excisions required to achieve negative margins.Results:In total, 129 patients with 205 NMSC lesions were retrospectively reviewed. An estimated 69 lesions (33.7%) were located in high risk areas, as defined by the National Comprehensive Cancer Network. Negative margins were achieved in 191 (93.2%) lesions. In 88.3% of lesions (n = 181/205), negative margins were achieved in 2 or less excisions. 12 lesions (5.9%) were referred for MMS.Conclusions:Our results demonstrate that SE is an effective modality for definitive removal of NMSC. Recent research reveals that SE is much less expensive than MMS, and therefore places a smaller financial burden on the patient and the healthcare system as a whole. Relative to MMS, SE offers similar if not increased benefits for lower cost. Our findings highlight the need to critically reassess the select indications for MMS.

The Treatment of Non-Melanoma Skin Cancer with Image-Guided Superficial Radiation Therapy: An Analysis of 2917 Invasive and In Situ Keratinocytic Carcinoma Lesions

IntroductionAn image-guided form of superficial ionizing radiation therapy (IGSRT) is becoming a commonly used alternative to surgery for non-melanoma skin cancer (NMSC). However, there is little literature evidence evaluating the efficacy and safety of this approach. This study evaluates the efficacy and safety of IGSRT in treating a large number of patients with NMSC.MethodsThe medical records of 1632 stage 0–II patients with 2917 invasive and in situ NMSC lesions treated from years 2017 to 2020 were reviewed. No patients had clinical evidence of regional lymph node or distant disease at presentation.ResultsTreatment, guided by pre-treatment ultrasound imaging to adjust radiation energy and dose, combined with a fractionation treatment schedule of 20 or more treatment fractions, was safe and well tolerated. Of 2917 NMSC lesions treated, local tumor control was achieved in 2897 lesions, representing a 99.3% rate of control.ConclusionIGSRT should be considered as a first-line option for treating NMSC tumors in suitable early stage patients. Cure rates observed in this initial period of follow-up are similar, and potentially superior with further follow-up, to traditional superficial radiation therapy (SRT) and surgical options.Supplementary InformationThe online version contains supplementary material available at 10.1007/s40487-021-00138-4.

Skin cancer and sun protection practices in Fanconi anemia patients: A cross-sectional study

Skin cancer and sun protection practices in Fanconi anemia patients: A cross-sectional study

A More Severe Non-melanoma Skin Cancer Phenotype Is Seen in Patients with Inflammatory Bowel Disease on Tumor Necrosis Factor-α Antagonists

Limited data suggest that non-melanoma skin cancer (NMSC) risk is higher in patients with inflammatory bowel disease (IBD) particularly in those on a tumor necrosis factor-α antagonist (TNF antagonist). It remains unknown whether TNF antagonist exposure alters the clinical course of NMSC in patients with IBD or if this therapy should be discontinued. To assess the impact of TNF antagonist exposure on NMSC severity, recurrence and need for ancillary treatments. Patients with IBD seen at London Health Sciences Centre, London, Canada were assessed for a history of NMSC and pre-diagnosis TNF antagonist exposure. NMSC severity (low risk and high risk), ancillary NMSC therapies, including chemo or radiotherapy, and changes to IBD therapy were assessed. Eleven of 472 patients with IBD reviewed were diagnosed with NMSC. Sixty-four percent (7/11) were on a TNF antagonist at the time of NMSC diagnosis. All patients with TNF antagonist exposure, (7/7) presented with a high-risk lesion based on National Comprehensive Cancer Network (NCCN) clinical practice guidelines. The incidence of positive margins was 42.9% (3/7) and 14.3% (1/7) required ancillary therapy. No metastatic disease was seen. TNF antagonist therapy was discontinued in a single patient due to NMSC diagnosis. Recurrent NMSC lesions were not seen in any of the TNF antagonist exposed patients. In this case series, TNF antagonist exposure may be associated with a severe NMSC clinical course. Larger studies are needed to confirm whether TNF antagonist discontinuation should be considered in the setting of NMSC diagnosis in IBD.

Weekly High-Dose Rate Brachytherapy Via Surface Applicator For Non-Melanoma Skin Cancers In The Elderly

Among patients treated with brachytherapy for non-melanoma skin cancers (NMSCs), including squamous cell carcinoma (SCC) and basal cell carcinoma (BCC), there exists a wide variety in dose, fractionation, and schedules employed. We retrospectively analyzed a hypofractionated regimen delivering 36 Gy in 6 weekly fractions to assess its safety and efficacy for the treatment of NMSCs in the elderly. All elderly (> 70 years old) patients treated in 2016 to 2019 with follow-up were included. In total, 46 patients with 63 NMSC lesions were treated using iridium-192 high-dose rate brachytherapy (HDR) delivered with custom molds containing catheters to encompass the tumor or tumor bed with a margin. The dose scheme employed was a weekly hypofractionated regimen of 36 Gy in 6 weekly fractions. Only 7 lesions (11.1%) underwent a more extensive excision than a biopsy. Acute and late toxicity were graded as per CTCAE version 5. Cosmesis was graded as “excellent” (similar to surrounding untreated skin), “good” (minimal changes), or “poor” (extensive telangiectasia, ulceration, or scar tissue). Kaplan-Meier curves were used to assess local control. Median age at treatment initiation was 85.8 years (range: 71.2-98.7), and 20 patients (43.5%) were female. Performance statuses ranged from 0 to 4 with 30.4% ECOG 0-1, 41.3% ECOG 2, and 28.3% ECOG 3-4. Median time from first treatment to last was 35 days (range: 28-70), and median follow-up was 8.6 months (range: 1.3-35.9). 35 lesions (55.6%) were BCC, and most lesions (81.0%) were located on the head and neck, including 20 on the nose (31.7%). All patients experienced acute toxicity with grade 1 occurring in 66.7%, grade 2 in 28.6%, and grade 3 in 4.8%. Lesions were not evaluated during follow-up in 5 cases (7.9%), and grade ≥ 2 late or persistent toxicity occurred in 12.1%. Overall cosmetic outcome was determined to be “excellent” or “good” following 54 treatments (93.1% of evaluable lesions). There was a higher incidence of “poor” cosmesis for lesions located on the lower extremities (33.3% vs. 3.8%, p = 0.049) and larger lesions (median: 11.8 vs. 5.1 cc, p = 0.031). Recurrence occurred in 3 lesions (4.8%) with 1 BCC on the bridge of the nose experiencing failure 8 months after completing treatment and 2 SCC lesions exhibiting persistent disease initially thought to be a poor cosmetic outcome, 1 on the nasal ala (confirmed at 6 months) and 1 on the scalp vertex (confirmed at 18 months). Estimated local control was 100% at 6 months, 94.5% at 12 months, and 88.2% at 24 months. Five patients (10.9%) have died since completing treatment, none due to disease progression. Our results suggest a hypofractionated regimen consisting of 36 Gy in 6 weekly fractions delivered with high-dose rate brachytherapy via surface applicator represents both a safe and an effective treatment of non-melanoma skin cancers in elderly patients.

Near-infrared heating of skin to delineate non-melanoma skin cancer lesions: A pilot study.

Surgical excision is a mainstay of treatment for non-melanoma skin cancer (NMSC); improving margin delineation can reduce the need for further monitoring/treatment. The objective of this pilot study was to determine if near-infrared radiation (NIR) application to skin causes visible changes in normal and NMSC skin, to help delineate margins. Eleven biopsy-proven NMSC lesions were included. The skin was then heated under a 175W NIR heating bulb; margins were traced onto acetate film before and after heating. Lesions were then randomly assigned to excision based on pre- or post-heating margins. Composite images were generated by overlaying the heat and no-heat lesion contours. All specimens were sent for histopathology. The range of closest margins in the control group was 2.0-3.0mm with a median of 2.0mm; the range in the intervention group was 4.0-9.0mm with a median of 5.0mm. Composite images showed larger heat contours when the initial lesion was larger. There was a statistically significant difference between the two groups. Overall, NIR light caused visible hyperaemia to skin, and more intense erythema to malignant skin lesions. Near-infrared light may have use in an outpatient setting for skin cancer delineation, possibly reducing the rate of positive margins.

555 Practice changing landmark study- multi-institutional analysis of image guided superficial radiotherapy (IGSRT) for the treatment of non-melanoma skin cancer (NMSC)

Practice changing landmark study- multi-institutional analysis of image guided superficial radiotherapy (IGSRT) for the treatment of non-melanoma skin cancer (NMSC). NMSC is generally treated in dermatology offices using surgical techniques. This study presents the largest multi-institutional retrospective modern series of Image Guided Superficial Radiotherapy (IGSRT) for Non-Melanoma Skin Cancer (NMSC). Between July 2013 and December 2019, 2424 NMSC lesions treated with IGSRT at 3 clinics in Texas and 1 clinic in NY were analysed. All lesions received 50, 70 or 100 kiloVoltage(kV) energy IGSRT 2-4 times weekly. KV energy selection was determined by ultrasound depth measurements and/or tumor characteristics. Patients returned 3-6 weeks after completion of therapy for dermoscopy/clinical evaluation and ultrasound imaging to confirm complete tumor clearance. Patients were then followed every 2-12 months thereafter. Any lesions in the treatment site suspicious for residual or recurrent tumor were biopsied. Exclusion criteria included tumors greater than 4 cm in diameter or non-movable tumors adherent to deeper structures. Follow-up ranged from 0.1-62.8months. At a mean follow up of 15.8 months, 29 patients with 77 lesions expired, all without recurrence. Kaplan-Meier (KM)Tumor control rates at 1, 2 and 5 years were 99.5%, 99.4% and 99.4% respectively. One, 2 and 5 year KM Overall-Survival (OS) for the entire group was 97.6%, 95.8% and 85.8% and unaffected by disease status or treatment. This study represents the largest study of NMSC treated with non-invasive IGSRT. The 99% cure rate is comparable to the best cure rates of other invasive modalities such as Mohs micrographic surgery. This innovative non-surgical technology with its high cure rate in the treatment of NMSC has the potential to transform the practice of dermatology with regard to treatment of NMSC.

Diffuse reflectance spectroscopy as a potential method for nonmelanoma skin cancer margin assessment

AbstractThe standard‐of‐care for nonmelanoma skin cancer (NMSC), including basal cell carcinoma (BCC) and squamous cell carcinoma (SCC), is surgical excision of the tumor. To ensure removal of the entire tumor and minimize removal of healthy tissue, a tool for quick discrimination between cancerous and normal skin is needed. We propose using diffuse reflectance spectroscopy (DRS) to assess tumor margins. We collected two independent clinical datasets. Using a clinical study of 31 patients with 50 NMSC lesions, we trained models including DRS data normalization, a physiological model, parameter selection and logistic regression classifiers. We tested our models on a second clinical dataset of 56 patients with 68 NMSC lesions. Our test results showed the area under the ROC curve of 0.94 for BCC vs normal and 0.90 for SCC vs normal. When applying a threshold selected using the training dataset to the test dataset, for BCC vs normal, specificity is 89% and sensitivity is 87%; for SCC vs normal, specificity is 65% and sensitivity is 97%. This study indicates that DRS can be potentially used to map the tumor margin prior to surgery and monitor margins during the surgery on the surface of the skin.