Mohs micrographic surgery

Artificial Intelligence for Mohs and Dermatologic Surgery: A Systematic Review and Meta-Analysis

BACKGROUND

Over the past decade, several studies have shown that potential of artificial intelligence (AI) in dermatology. However, there has yet to be a systematic review evaluating the usage of AI specifically within the field of Mohs micrographic surgery (MMS).

OBJECTIVE

In this review, we aimed to comprehensively evaluate the current state, efficacy, and future implications of AI when applied to MMS for the treatment of nonmelanoma skin cancers (NMSC).

MATERIALS AND METHODS

A systematic review and meta-analysis was conducted following PRISMA guidelines across several databases, including PubMed/MEDLINE, Embase, and Cochrane libraries. A predefined protocol was registered in PROSPERO, with literature search involving specific keywords related to AI and Mohs surgery for NMSC.

RESULTS

From 23 studies evaluated, our results find that AI shows promise as a prediction tool for precisely identifying NMSC in tissue sections during MMS. Furthermore, high AUC and concordance values were also found across the various usages of AI in MMS, including margin control, surgical recommendations, similarity metrics, and in the prediction of stage and construction complexity.

CONCLUSION

The findings of this review suggest promising potential for AI to enhance the accuracy and efficiency of Mohs surgery, particularly for NMSC.

Mohs micrographic surgery in immunosuppressed vs immunocompetent patients: Results of a prospective nationwide cohort study (REGESMOHS, Spanish registry of Mohs surgery)

BACKGROUND

Immunosuppressed (IS) patients, particularly solid organ transplant recipients and those on immunosuppressive therapy, face a higher incidence and recurrence of nonmelanoma skin cancers (NMSC), including basal cell carcinoma (BCC) and squamous cell carcinoma (SCC). Mohs micrographic surgery (MMS) is the preferred treatment for high-risk NMSC due to its high cure rate and margin examination capabilities. However, IS patients may experience more complications, such as surgical site infections, and a greater risk of recurrence, making their outcomes a subject of interest.

OBJECTIVES

This study aimed to compare IS and immunocompetent (IC) patients undergoing MMS for NMSC in terms of baseline characteristics, intra- and post-surgical complications, and postoperative recurrence rates.

METHODS

The study utilized data from the REGESMOHS registry, a 7-year prospective cohort study in Spain. It included 5226 patients, categorizing them into IC (5069) and IS (157) groups. IS patients included solid organ transplant recipients, those on immunosuppressive treatments, individuals with haematological tumours and HIV-positive patients. Patient data, tumour characteristics, surgical details and outcomes were collected and analysed.

RESULTS

IS patients demonstrated a higher proportion of SCC, multiple synchronous tumours and tumours invading deeper structures. Complex closures, unfinished MMS and more surgical sections were observed in the IS group. Although intra-operative morbidity was higher among IS patients, this difference became non-significant when adjusted for other variables such as year of surgery, antiplatelet/anticoagulant treatment or type of closure. Importantly, IS patients had a substantially higher recurrence rate (IRR 2.79) compared to IC patients.

CONCLUSIONS

This study suggests that IS patients may be at a higher risk of development of AE such as bleeding or tumour necrosis and are at a higher risk of tumour recurrence. Close follow-up and consideration of the specific characteristics of NMSC in IS patients are crucial. Further research with extended follow-up is needed to better understand the long-term outcomes for this patient group.

Using optical coherence tomography to optimize Mohs micrographic surgery

Mohs micrographic surgery (MMS) is considered the gold standard for treating high-risk cutaneous basal cell carcinoma (BCC), but is expensive, time-consuming, and can be unpredictable as to how many stages will be required or how large the final lesion and corresponding surgical defect will be. This study is meant to investigate whether optical coherence tomography (OCT), a highly researched modality in dermatology, can be used preoperatively to map out the borders of BCC, resulting in fewer stages of MMS or a smaller final defect. In this prospective study, 22 patients with BCC undergoing surgical excision were enrolled at a single institution. All patients had previously received a diagnostic biopsy providing confirmation of BCC and had been referred to our center for excision with MMS. Immediately prior to performing MMS, OCT was used to map the borders of the lesion. MMS then proceeded according to standard protocol. OCT images were compared to histopathology for agreement. Histopathologic analysis of 7 of 22 MMS specimens (32%) revealed a total absence of BCC, indicating resolution of BCC after previous diagnostic biopsy. This outcome was correctly predicted by OCT imaging in 6 of 7 cases (86%). Nine tumors (9/22, 41%) had true BCC and required a single MMS stage, which was successfully predicted by pre-operative OCT analysis in 7 of 9 cases (78%). The final six tumors (27%) had true BCC and required two MMS stages for complete excision; preoperative OCT successfully predicted the need for a second stage in five cases (5/6, 83.3%). Overall, OCT diagnosed BCC with 95.5% accuracy (Cohen's kappa, κ = 0.89 (p-value =  < 0.01) in the center of the lesion. Following a diagnostic biopsy, OCT can be used to verify the existence or absence of residual basal cell carcinoma. When residual tumor is present that requires excision with MMS, OCT can be used to predict tumor borders, optimize surgery and minimize the need for additional surgical stages.

Rapidly Growing and Aggressive Squamous Cell Carcinoma of the Forearm: A Report of Successful Treatment With Mohs Surgery and Complex Reconstruction With Rhombic Triple Z-Plasty

Reconstruction of complex post-surgical wounds requires functional and aesthetic considerations. We present a case of a complex radial-dorsal forearm defect in a patient who underwent Mohs surgery for an aggressive and rapidly growing squamous cell carcinoma. Following complete tumor excision, we utilized a modified rhombic flap for complete wound coverage with long-term conservation of extensor function. The rhombic flap modification included three Z-plasties at the flap base to add rotational components to the flap transposition. Long-term follow-up showed acceptable cosmesis, preserved extensor tendon function, and no evidence of tumor recurrence.

Intraoperative margin assessment for basal cell carcinoma with deep learning and histologic tumor mapping to surgical site

Successful treatment of solid cancers relies on complete surgical excision of the tumor either for definitive treatment or before adjuvant therapy. Intraoperative and postoperative radial sectioning, the most common form of margin assessment, can lead to incomplete excision and increase the risk of recurrence and repeat procedures. Mohs Micrographic Surgery is associated with complete removal of basal cell and squamous cell carcinoma through real-time margin assessment of 100% of the peripheral and deep margins. Real-time assessment in many tumor types is constrained by tissue size, complexity, and specimen processing / assessment time during general anesthesia. We developed an artificial intelligence platform to reduce the tissue preprocessing and histological assessment time through automated grossing recommendations, mapping and orientation of tumor to the surgical specimen. Using basal cell carcinoma as a model system, results demonstrate that this approach can address surgical laboratory efficiency bottlenecks for rapid and complete intraoperative margin assessment.

Reported Outcome Measures in Mohs Micrographic Surgery in Studies With Defined Techniques for Embedding and Processing of Tissue: A Systematic Review

BACKGROUND

Mohs micrographic surgery (MMS) is a technique that combines surgical excision and histologic evaluation to achieve higher cure rates for skin cancer than traditional surgical excision. Competing performance measures have fostered numerous histologic techniques for MMS.

OBJECTIVE

To analyze differences in primary outcomes in the published literature regarding the technique of tissue processing and embedding during the MMS process.

METHODS

A systematic review was performed of the published literature in MEDLINE, PubMed, Embase, and Cochrane library that included a description of the manipulation of tissue during the grossing and embedding steps of MMS.

RESULTS

Inclusion criteria were met by 61 articles. Of these studies, the cure/recurrence rate was assessed in 1 article (1.6%), tissue conservation was assessed in 47 (77%), time-saving was assessed in 35 (57%), cost-saving was assessed in 6 (10%), and decreased artifact were assessed in 20 (33%).

CONCLUSION

There is a lack of standardization for assessing clinical outcomes in the published literature regarding MMS process techniques. Cure is a critical outcome in studies comparing MMS processing methodologies.

Mohs Micrographic Surgery With Digital Pathology Improves Surgical Quality and Efficiency: A Retrospective Cohort Study

BACKGROUND

Mohs micrographic surgery, involving pathology of the surgical margin, has the lowest recurrence rate for skin cancer. Moreover, because of technological advances, digital pathology systems are gradually being adopted in hospitals. Yongin Severance Hospital was the first hospital to construct a fully digitalized pathology system in Korea.

OBJECTIVE

To evaluate the efficiency and characteristics of the digital pathology system for Mohs micrographic surgery.

METHODS

The medical records of 80 patients with skin cancer who underwent Mohs micrographic surgery from March 2020 to August 2022 were analyzed for the number of frozen margins, number of stages, operation time, and recurrence rate to compare cases based on the pathology system.

RESULTS

Overall, 23 and 57 patients were examined using the conventional and digital pathology systems, respectively. The mean number of final stages was 0.494 lower ( p -value = .008), the time from the previous to the next stage was 0.687-fold shorter ( p = .002), and the rate of switching from positive to negative margins was 1.990 times higher ( p = .044) in the digital than the conventional group.

LIMITATIONS

Retrospective single-center experience; short follow-up time.

CONCLUSION

Digital pathology reduces operative time and increases accuracy in Mohs micrographic surgery.

One-class machine learning classification of skin tissue based on manually scanned optical coherence tomography imaging

We investigated a method for automatic skin tissue characterization based on optical coherence tomography (OCT) imaging. We developed a manually scanned single fiber OCT instrument to perform in vivo skin imaging and tumor boundary assessment. The goal is to achieve more accurate tissue excision in Mohs micrographic surgery (MMS) and reduce the time required for MMS. The focus of this study was to develop a novel machine learning classification method to automatically identify abnormal skin tissues through one-class classification. We trained a deep convolutional neural network (CNN) with a U-Net architecture for automatic skin segmentation, used the pre-trained U-Net as a feature extractor, and trained one-class support vector machine (SVM) classifiers to detect abnormal tissues. The novelty of this study is the use of a neural network as a feature extractor and the use of a one-class SVM for abnormal tissue detection. Our approach eliminated the need to engineer the features for classification and eliminated the need to train the classifier with data obtained from abnormal tissues. To validate the effectiveness of the one-class classification method, we assessed the performance of our algorithm using computer synthesized data, and experimental data. We also performed a pilot study on a patient with skin cancer.

Assessment of Extramammary Paget Disease by Two-Photon Microscopy

Two-photon microscopy techniques are non-linear optical imaging methods which are gaining momentum in the investigation of fixed tissue sections, fresh tissue or even for in vivo experiments. Two-photon excited fluorescence and second harmonic generation are two non-linear optical contrast mechanisms which can be simultaneously used for offering complementary information on the tissue architecture. While the former can originate from endogenous autofluorescence sources (e.g., NADH, FAD, elastin, keratin, lipofuscins, or melanin), or exogenous eosin, the latter is generated in fibrillar structures within living organisms (e.g., collagen and myosin). Here we test the ability of both these contrast mechanisms to highlight features of the extramammary Paget disease on fixed tissue sections prepared for standard histological examination using immunohistochemical markers and hematoxylin and eosin staining. We also demonstrate the label-free abilities of both imaging techniques to highlight histological features on unstained fixed tissue sections. The study demonstrated that two-photon microscopy can detect specific cellular features of the extramammary Paget disease in good correlation with histopathological results.

Incidence and trends of basal cell carcinoma in Sweden: A population-based registry study

BACKGROUND

Basal cell carcinoma (BCC) is the most common skin cancer. Incidence is largely unknown because of incomplete, or lack of, registration in most countries.

OBJECTIVES

To assess current incidence rates and recent trends for BCC in the Swedish population.

METHODS

Patient- and tumour-related features of all histologically confirmed BCC tumours diagnosed in Sweden from 2004 to 2017 were extracted from the population-based Swedish BCC Registry. Incidence rates were standardized to the 2013 European Standard Population and trends were analysed using Poisson regression models.

RESULTS

Age-standardized person-based incidence rate of BCC in Sweden in 2017 was 405/100 000, rising from 308/100 000 in 2004, corresponding to an annual relative increase of 1.8% (women, 2.1%; men, 1.4%). Incidence was highest in the elderly and the most common tumour site was the head and neck. In 2017, the most common BCC subtypes were nodular and micronodular/infiltrative BCC (each 31%). Incidence of aggressive BCC subtypes increased faster than other subtypes.

CONCLUSIONS

BCC incidence rates in Sweden are relatively high and increasing. The increasing trends were more pronounced in women and for aggressive BCC subtypes.

Risk Factors and Rate of Recurrence after Mohs Surgery in Basal Cell and Squamous Cell Carcinomas: A Nationwide Prospective Cohort (REGESMOHS, Spanish Registry of Mohs Surgery)

Randomized studies to assess the efficacy of Mohs micrographic surgery in basal cell and squamous cell carcinomas are limited by methodological and ethical issues and a lack of long follow-up periods. This study presents the “real-life” results of a nationwide 7-years cohort on basal cell carcinoma and squamous cell carcinoma treated with Mohs micrographic surgery. A prospective cohort was conducted in 22 Spanish centres (from July 2013 to February 2020) and a multivariate analysis, including characteristics of patients, tumours, surgeries and follow-up, was performed. A total of 4,402 patients followed up for 12,111 patientyears for basal cell carcinoma, and 371 patients with 915 patient-years of follow-up for squamous cell carcinoma were recruited. Risk factors for recurrence included age, non-primary tumours and more stages or unfinished surgeries for both tumours, and immunosuppression for squamous cell carcinoma. Incidence rates of recurrence were 1.3 per 100 person-years for basal cell carcinoma (95% confidence interval 1.1– 1.5) and 4.5 for squamous cell carcinoma (95% confidence interval 3.3–6.1), being constant over time (0–5 years). In conclusion, follow-up strategies should be equally intense for at least the first 5 years, with special attention paid to squamous cell carcinoma (especially in immunosuppressed patients), elderly patients, non-primary tumours, and those procedures requiring more stages, or unfinished surgeries.

Review of Perineural Invasion in Keratinocyte Carcinomas

Perineural invasion is an infiltrative process of peripheral nerves by the primary neoplasm within the immediate vicinity. Aggressive forms of keratinocyte carcinomas, such as basal cell and squamous cell carcinomas, may feature perineural invasion, which is often associated with tumor recurrence and poorer prognosis. Diagnosis requires a high clinical suspicion. Imaging and histopathology are used to assess for extent of disease while surgical excision with complete circumferential peripheral and margin assessment is the treatment goal. However, there is still significant uncertainty about adjuvant chemotherapy and definitive management guidelines. Here, we summarize the current understanding of this complex pathogenic process, the clinical presentation, and the significance of perineural inflammation. We also discuss the recommendations about staging, prognosis, adjuvant radiotherapy, and general guidelines for managing keratinocyte carcinomas with perineural invasion. A better understanding of perineural invasion is essential to improve diagnosis, tailor interventions, and mitigate patient morbidity and mortality.

Selective-sampling Raman imaging techniques for ex vivo assessment of surgical margins in cancer surgery

One of the main challenges in cancer surgery is to ensure the complete excision of the tumour while sparing as much healthy tissue as possible. Histopathology, the gold-standard technique used to assess the surgical margins on the excised tissue, is often impractical for intra-operative use because of the time-consuming tissue cryo-sectioning and staining, and availability of histopathologists to assess stained tissue sections. Raman micro-spectroscopy is a powerful technique that can detect microscopic residual tumours on ex vivo tissue samples with accuracy, based entirely on intrinsic chemical differences. However, raster-scanning Raman micro-spectroscopy is a slow imaging technique that typically requires long data acquisition times wich are impractical for intra-operative use. Selective-sampling Raman imaging overcomes these limitations by using information regarding the spatial properties of the tissue to reduce the number of Raman spectra. This paper reviews the latest advances in selective-sampling Raman techniques and applications, mainly based on multimodal optical imaging. We also highlight the latest results of clinical integration of a prototype device for non-melanoma skin cancer. These promising results indicate the potential impact of Raman spectroscopy for providing fast and objective assessment of surgical margins, helping surgeons ensure the complete removal of tumour cells while sparing as much healthy tissue as possible.

Deep learning automated pathology in ex vivo microscopy

Standard histopathology is currently the gold standard for assessment of margin status in Mohs surgical removal of skin cancer. Ex vivo confocal microscopy (XVM) is potentially faster, less costly and inherently 3D/digital compared to standard histopathology. Despite these advantages, XVM use is not widespread due, in part, to the need for pathologists to retrain to interpret XVM images. We developed artificial intelligence (AI)-driven XVM pathology by implementing algorithms that render intuitive XVM pathology images identical to standard histopathology and produce automated tumor positivity maps. XVM images have fluorescence labeling of cellular and nuclear biology on the background of endogenous (unstained) reflectance contrast as a grounding counter-contrast. XVM images of 26 surgical excision specimens discarded after Mohs micrographic surgery were used to develop an XVM data pipeline with 4 stages: flattening, colorizing, enhancement and automated diagnosis. The first two stages were novel, deterministic image processing algorithms, and the second two were AI algorithms. Diagnostic sensitivity and specificity were calculated for basal cell carcinoma detection as proof of principal for the XVM image processing pipeline. The resulting diagnostic readouts mimicked the appearance of histopathology and found tumor positivity that required first collapsing the confocal stack to a 2D image optimized for cellular fluorescence contrast, then a dark field-to-bright field colorizing transformation, then either an AI image transformation for visual inspection or an AI diagnostic binary image segmentation of tumor obtaining a diagnostic sensitivity and specificity of 88% and 91% respectively. These results show that video-assisted micrographic XVM pathology could feasibly aid margin status determination in micrographic surgery of skin cancer.

Dermoscopic Findings in the Presurgical Evaluation of Basal Cell Carcinoma. A Prospective Study

BACKGROUND

Surgery is the best treatment for basal cell carcinoma (BCC); however, incomplete excisions are possible.

OBJECTIVE

Assessment of the accurateness of dermoscopy and clinical evaluation in the detection of borders of BCC and description of dermoscopic findings in clinically healthy tissue surrounding BCC.

MATERIALS AND METHODS

Eighty-eight lesions with clinical dermoscopic diagnosis of BCC were examined clinically and dermoscopically, to delineate the correct site of surgical incision, demarcating the respective margins with colred dermographic pencils. Specific dermoscopic features were searched in the skin adjacent to the demarcated clinical margin.

RESULTS

In 29 of 88 lesions, clinical and dermoscopic margins of the tumor coincided. In the remaining 59 (67%), 10 (16.9%) presented, in the lesion area identified under dermoscopy, classical criteria for BCC and 57 (96.6%) nonclassical criteria. Differences between clinical and dermoscopic margins were significantly more frequent in superficial BCCs (p = .006). The frequency was not significantly different (p = .85) in relation to body sites.

CONCLUSION

Dermoscopy improves the identification of margins for surgical excision in BCC. The observation of nontraditional dermoscopic criteria of BCC, mainly pink-white areas and short telangiectasias in the area between clinically and dermoscopically detected margins, helps to define the actual tumoral margins and to achieve a really radical excision.

Clinical integration of fast Raman spectroscopy for Mohs micrographic surgery of basal cell carcinoma

We present the first clinical integration of a prototype device based on integrated auto-fluorescence imaging and Raman spectroscopy (Fast Raman device) for intra-operative assessment of surgical margins during Mohs micrographic surgery of basal cell carcinoma (BCC). Fresh skin specimens from 112 patients were used to optimise the tissue pre-processing and the Fast Raman algorithms to enable an analysis of complete Mohs layers within 30 minutes. The optimisation allowed >95% of the resection surface area to be investigated (including the deep and epidermal margins). The Fast Raman device was then used to analyse skin layers excised from the most relevant anatomical sites (nose, temple, eyelid, cheek, forehead, eyebrow and lip) and to detect the three main types of BCC (nodular, superficial and infiltrative). These results suggest that the Fast Raman technique is a promising tool to provide an objective diagnosis "tumour clear yes/no" during Mohs surgery of BCC. This clinical integration study is a key step towards a larger scale diagnosis test accuracy study to reliably determine the sensitivity and specificity in a clinical setting.

Complex skin cancer treatment requiring reconstructive plastic surgery: an interview study on the experiences and needs of patients

To provide patient-centered care, it is essential to explore what patients consider important and to adjust care accordingly. This may specifically be relevant for patients with complex skin cancer, for whom the care process is often more complicated and psychological and social problems may play a larger role. The objective was to explore the experiences and needs of patients who had undergone surgical treatment by a dermatologist for a complex skin cancer with a subsequent reconstruction by a plastic surgeon. An interview study was conducted among 16 patients who had undergone surgical treatment by a dermatologist and reconstruction by a plastic surgeon for basal cell carcinoma, cutaneous squamous cell carcinoma, or lentigo maligna. The interviews focused on patients’ experiences and needs regarding care using a predefined topic list. All interviews were audio-taped, transcribed verbatim and inductively analyzed using Atlas.ti. Patients reported a need for a skilled and friendly physician who tailors information and communication to their individual situation. A need for continuity of care and improved collaboration between healthcare providers was also emphasized. Furthermore, patients experienced complications and unmet expectations and expressed a need for shared decision-making at various steps throughout the treatment process (depending on age). Patients also considered completeness of tumor removal, follow-up visits with multiple specialists to be planned the same day and recognition of the psychological impact of the disease on the partner important. To improve patient-centered care for complex skin cancer patients, more efforts should be directed towards improving continuity of care and collaboration. Furthermore, it is advocated for physicians to be sensitive to the individual needs of patients and their partner and adjust information, communication and (supportive) care accordingly.

Muffin Technique Micrographic Surgery for Non-melanoma Skin Cancer

Background: Mohs micrographic surgery (MMS) is the gold standard treatment for high-risk facial non-melanoma skin cancer. However, patients' access to MMS is limited by cost. The muffin technique micrographic surgery (MTMS) is an alternative micrographic technique wherein the entire excised margin is evaluated post-operatively by a pathologist using paraffin-embedded material. Herein, we describe the implementation and the preliminary results of MTMS in an academic dermatology center.

Objective: To describe the MTMS and outline its efficacy and safety in a real-world clinical academic setting.

Methods: A retrospective chart review was conducted of all patients with basal cell carcinoma (BCC) and squamous cell carcinoma (SCC) who underwent MTMS at the University of Alberta Dermatology Center from June 2016 until July 2019.

Results: A total of 69 patients were included (64 BCCs and 5 SCCs). 68.1% of surgeries had clear margins following the first incision, 100% after second round re-excisions. There were no observed cases of tumor recurrence after a median 40 months of follow-up. There were no major adverse events or complications.

Conclusions: MTMS is a superior alternative to simple excision of skin cancer by providing full margin control and residual tumor mapping.

Surgical treatment of basal cell carcinoma: a case series on factors influencing the risk of an incomplete primary excision

BACKGROUND

Basal cell carcinoma (BCC) is the most common skin cancer form, and one first-line treatment is surgical excision. Complete excision is vital to minimize risk of recurrence. Studies on occurrence of incomplete excisions have given diverse results and seldom include large populations from a dermatological setting.

OBJECTIVES

The rate of positive surgical margins in primary surgery of BCC at a tertiary dermatology clinic is studied. Factors associated with an incomplete primary excision are analysed.

METHODS

Patients scheduled for standard excision, without perioperative margin control, of BCC during the years 2008-2015 were prospectively enrolled in the study. Tumour-specific factors, including histopathologic subtype, as well as postoperative outcome were registered. Incomplete excisions were analysed in relation to patient- and tumour-related factors.

RESULTS

In total, 4.6% of 3911 BCC tumours were incompletely excised. The rate of incomplete excisions was higher for facial tumours and among tumours with an aggressive histological subtype. Morpheiform BCC on the nose or ear had the highest rate of an incomplete excision, 61.5% and 50%, respectively.

CONCLUSIONS

Most BCCs, irrespective of subtype, were completely excised during the primary excision. Tumour sites nose and ears were associated with the highest rate of positive primary surgical margins, especially for infiltrative or morpheiform BCCs. Surgery with perioperative examination of margins is strongly recommended for these tumours.

Darier and Ferrand's dermatofibrosarcoma: A carcinologic and cosmetologic challenge in a low-income country

INTRODUCTION

Dermatofibrosarcoma (DFS) is a common dermic sarcoma. It is a local malignant tumor occurring in young adults. The recurrence potential justifies an R0-type surgery with a three centimeters margin. We report our experience of the management of locally advanced DFS by resection and reconstructive surgery.

METHODS

It is an ongoing descriptive study spanned from June 2005 to December 2018. We included all DFS cases treated by curative resection and reconstruction. A total of eight cases of DFS among 108 soft tissue sarcomas were studied. All patients were males. The mean age was 41.8 years [32-60]. Carcinologic results, cosmetic results, and outcomes were analyzed.

RESULTS

R0-type resection was performed in six cases. In two cases, the resection was R1-type and resulted in amputation. In four cases, it was an iterative surgery. Average desease duration was 4 years [1-8]. Reconstructive surgery was needed for wound closure in six cases. Wounds healed in 28 days [18-90]. Outcomes showed hyperchromic keloid scars (N=2) at the trunk localization.

CONCLUSION

DFS is a common cancer with a good outcome if managed earliest. Delayed diagnoses and inadequate first-time surgery led to tumor extension and recurrences. Locally advanced tumors management needs extensive resections and reconstructive surgery. In addition to surgery, Imatinib and radiotherapy improve outcomes, but are not available in our context.

Predictive Value of Preoperative Periocular Skin Cancer Measurements for Final Mohs Defect Size

PURPOSE

To evaluate the relationship between pre-Mohs skin cancer lesion measurements with the post-Mohs defect size in order to most accurately estimate post-Mohs defect size.

METHODS

This is a retrospective analysis of patients who underwent Mohs excision by one of 3 Mohs surgeons followed by reconstruction for basal cell carcinoma or squamous cell carcinoma of the eyelid. The study included all patients from January 2011 to May 2018 operated on by a single oculoplastic surgeon (R.M.) at the University of Texas Southwestern Medical Center. Maximum horizontal and vertical (H/V) dimensions were determined clinically by Mohs surgeons at the time of excision and photographs of the lesion and defect size were analyzed in order to determine the total area of the lesion preoperatively and the defect postoperatively with Image J using H/V dimensions and the area tracing function.

RESULTS

Forty-two patients with periocular skin cancers underwent Mohs resection followed by reconstruction. The Mohs defect was overall 4.88 times the size of the preoperative skin cancer measurement using maximum H/V dimensions by Mohs surgeons (p < 0.0001). When using Image J, the area of the Mohs defect was 6.5 times the size of the preoperative lesion (p < 0.0001) using both the maximum H/V dimensions and the area tracing function. There was a statistically significant difference between the Image J area tracing and area determined with H/V dimensions by both the Mohs surgeon and Image J.

CONCLUSIONS

Postoperative Mohs defect size can be estimated based on maximum H/V dimensions clinically or with Image J technology. Image J digital photograph analysis using the area tracing function more accurately determines the pre-Mohs lesion size and the post-Mohs defect area when compared with standard maximum H/V measurements and digital photographic analysis of maximum H/V measurements with Image J.The preoperative periocular skin cancer measurements can assist in determining the post-Mohs defect size.

Management of keratinocyte carcinoma - Special considerations in the elderly

Keratinocyte carcinomas (KCs) are now an epidemic in The United States of America, especially in elderly patients. KCs, including basal cell carcinoma and squamous cell carcinoma, can lead to disfigurement and occasionally death. However, the lower mortality rate associated with KC compared with melanoma allows for increased flexibility in the selection of treatment. Flexibility in treatment is particularly important in the elderly given that this patient population often has medical comorbidities that should be considered. These patients may have multiple KCs, higher risk tolerance to recurrence, and different concerns about cosmetic outcomes compared with their younger counterparts. We review treatment options for KCs and how the selection of each option may affect the elderly patient.

Pharmacologic and Nonpharmacologic Interventions for Perioperative Anxiety in Patients Undergoing Mohs Micrographic Surgery: A Systematic Review

BACKGROUND

Perioperative anxiety is associated with negative patient outcomes in Mohs micrographic surgery (MMS). Both pharmacologic and nonpharmacologic therapies have been used to alleviate perioperative anxiety in MMS.

OBJECTIVE

To systematically evaluate the efficacy of therapies aimed at reducing perioperative anxiety in MMS.

METHODS AND MATERIALS

Eligible articles were identified using PubMed MEDLINE, Cochrane Central Register of Controlled Trials, metaRegister of Controlled Trials, ClinicalTrials.gov, and World Health Organization International Clinical Trials Registry Platform. All available studies investigating interventions to reduce perioperative anxiety during MMS were considered.

RESULTS

Of the 183 abstracts identified and screened, 5 studies met inclusion criteria. Three studies reported a postintervention reduction in patient anxiety (midazolam, educational video, and personalized music). Two studies reporting on similar interventions did not find an effect.

CONCLUSION

There is currently limited evidence to support either pharmacologic or nonpharmacologic therapy for alleviation of perioperative patient anxiety in MMS. Midazolam may provide patients a short-term benefit, though any estimate of the effect is very uncertain. Personalized music may be a promising nonpharmacologic intervention for future research.

Synoptic reporting in Mohs micrographic surgery

There is currently no standardised reporting format for Mohs surgery with its operation reports mostly written in a narrative form making them prone to unintentional errors and omission of necessary data. Synoptic histology reporting is used to describe excised skin cancers such as melanomas and, more recently, squamous cell and basal cell carcinomas. Since Mohs surgery is utilised as the gold standard treatment for locally invasive squamous and basal cell carcinomas, we propose the use of our model of synoptic reporting to ensure the completeness and consistency of Mohs surgery operation reports.

Circulating essential metals and lung cancer: Risk assessment and potential molecular effects

OBJECTIVE

Essential metals play important roles in the carcinogenic process. However, seldom longitudinal investigations have evaluated their roles in lung cancer development. We aimed to investigate the associations between multiple essential metals and lung cancer incidence and to explore the potential mechanisms.

METHODS

A nested case-control study of 440 incident lung cancer cases and 1:3 frequency matched 1320 healthy controls from the Dongfeng-Tongji Cohort was conducted. The baseline plasma concentrations of 11 essential metals (cobalt, copper, iron, manganese, molybdenum, rubidium, selenium, strontium, stannum, vanadium, and zinc) were measured, and their associations with lung cancer incidence were estimated. Effect of positive metal (zinc) on 4-year telomere attrition was then evaluated among an occupational cohort of 724 workers. We also assessed the transcriptional regulation effects of plasma zinc on mRNA expression profiles, and the expressions of zinc-related genes were further compared in pair-wised lung tumor and normal tissues.

RESULTS

Elevated plasma level of zinc was associated with lower incident risk of lung cancer [OR (95% CI) = 0.89 (0.79, 0.99)] and decreased 4-year telomere attrition [β (95% CI) = -0.73 (-1.27, -0.19)]. These effects were pronounced among males. In particularly, zinc could regulate the expressions of 8 cancer-related genes, including SOD1, APE, TP53BP1, WDR33, LAPTM4B, TRIT1, HUWE1, and ZNF813, which were over-expressed in lung tumor tissues.

CONCLUSIONS

We propose that high plasma zinc could prevent incident lung cancer, probably by slowing down telomere attrition and regulating the expressions of cancer-related genes. These results provided a new insight into lung cancer prevention.

Slide-free imaging of hematoxylin-eosin stained whole-mount tissues using combined third-harmonic generation and three-photon fluorescence microscopy

Intraoperative margin assessment of surgical tissues during cancer surgery is clinically important, especially in the case of tissue conserving surgery like Mohs micrographic surgery in which minimization of the surgical area is considered crucial. Frozen pathology is the gold standard of assessing excised tissues for signs of remaining cancerous lesions. The current protocol, however, is time-consuming and labor-intensive. Instead of the complex frozen sectioning, staining, and traditional white light microscopy imaging protocol, optically sectioned histopathological imaging of hematoxylin-eosin stained whole-mount skin tissues with a subfemtoliter resolution is demonstrated by using nonlinear microscopy in this study. With our proposed method, the reagents of staining and the contrast of imaging are fully consistent with the current clinical standard of frozen pathology, thus facilitating rapid intraoperative assessment of surgical tissues for future applications. Image: Slide-free nonlinear microscopy imaging of H&E stained whole-mount skin tissue showing the morphology of sweat glands.

The role of EGFR overexpression on the recurrence of basal cell carcinomas with positive surgical margins

BACKGROUND

Epidermal growth factor receptor (EGFR) expression may have role on recurrence of basal cell carcinoma (BCC) with positive surgical margin(s).

OBJECTIVE

The aim was to investigate the role of genetic expression changes of EGFR on recurrence rates in patients in follow up with surgically excised BCC with positive surgical margin(s).

METHODS

Thirty-four surgical margin-positive BCC lesions that were closely followed up without an immediate reoperation were included in this study. Real-time polymerase chain reaction (PCR) was performed from the both healthy and tumoral tissue samples.

RESULTS

EGFR was expressed at a significantly higher rate in tumoral tissues compared to healthy tissues (p < 0,05). In patients with recurrence lesions, EGFR expression was 6,66 times higher compared to patients with non-recurrent. Also, there was statistically significant difference EGFR expression for infiltrative subtypes (p < 0,05).

CONCLUSION

Our study focuses on the role of EGFR overexpression specifically and outcomes for recurrent and infiltrative subtyped lesions are significant for both clinic and pathogenesis of BCC. Similar studies have to be performed with high numbered patient groups.

Mapping of cutaneous melanoma by femtosecond laser-induced breakdown spectroscopy

Surgical excision (Mohs micrographic surgery) is the standard procedure to treat a melanoma, in which an in situ histologic examination of sectioned skin is carried out repeatedly until no cancer cells are detected. The possibility to identify melanoma from the surrounding skin by femtosecond laser-induced breakdown spectroscopy (fs-LIBS) is investigated. For experiments, melanoma induced on a hairless mouse by injection of B16/F10 murine melanoma cell was sampled in the form of frozen tissue sections as in Mohs surgery and analyzed by fs-LIBS (λ  =  1030  nm, τ  =  550  fs). For analysis, the magnesium signal normalized by carbon intensity was utilized to construct an intensity map around the cancer, including both melanoma and surrounding dermis. The intensity map showed a close match to the optically observed morphological and histological features near the cancer region. The results showed that when incorporated into the existing micrographic surgery procedure, fs-LIBS could be a useful tool for histopathologic interpretation of skin cancer possibly with significant reduction of histologic examination time.

Effectiveness of Mohs micrographic surgery for nonmelanoma skin cancer: a systematic review protocol

REVIEW OBJECTIVES/QUESTIONS

The objective of the review is to evaluate the effectiveness of Mohs micrographic surgery on the mortality, recurrence and quality of life of patients with nonmelanoma skin cancers when compared with other treatment modalities.Specifically, it aims to examine the effectiveness of Mohs micrographic surgery compared with other treatment modalities such as excisional surgery, curettage and electrodessication and radiation therapy, as well as nonsurgical/chemotherapeutic interventions such as topical 5-fluorouracil and imiquimod immunotherapy in the management of nonmelanoma skin cancers.

Mohs micrographic surgery for cutaneous malignancies: A focus review of its indications in pediatric age groups

Mohs micrographic surgery (MMS) is a highly specialized technique that has been successful in the treatment of a variety of skin tumors. The technique can be performed as an outpatient procedure and encompasses surgical excision and intraoperative assessment of tumor margins in one setting by the same physician. The process ensures precise margin control with maximal preservation of healthy tissues. Mohs micrographic surgery has been practiced worldwide, including in the United States, Europe (United Kingdom, Germany, Spain, Netherlands, Switzerland), and Australia. Although it is commonly performed in adults with greater success, it has been discussed less frequently in children. In this article, we describe several cutaneous tumors in children and the role of Mohs micrographic surgery in their management. A PubMed search was conducted to review the most common cutaneous tumors in children treated using Mohs micrographic surgery. In this review, we discuss indications for Mohs micrographic surgery and pertinent studies examining success rates in children. Mohs micrographic surgery has been used to treat several tumors in children and offers the advantage of high cure rates and tissue conservation. This report emphasizes the benefits of Mohs micrographic surgery in children and highlights several cutaneous tumors for which it has been used to treat successfully.

A Predictive Model for Primary Closure Lengths in Mohs Surgery Based on Skin Cancer Type, Dimensions, and Location

BACKGROUND

Surgical scar length is a common concern among patients undergoing Mohs micrographic surgery (MMS).

OBJECTIVE

This study evaluates 3 metrics of preoperative lesion size to determine which correlates best with primary linear closure lengths for nonmelanoma skin cancers (NMSCs) treated with MMS. This metric is then used to develop predictive models for linear closure lengths in 10 different anatomical regions.

MATERIALS AND METHODS

A retrospective study of 4,049 NMSCs treated with MMS and repaired with primary linear closure was conducted. Primary closure lengths were plotted against preoperative lesion circumference, area, and short axis length. Linear regression analysis was performed.

RESULTS

Preoperative NMSC circumference correlated best with closure length. Twenty-one of the 28 regression models had coefficients of determination (R) above 0.5. Closure lengths increased by 0.52 to 1.1 mm, depending on location, for every millimeter increase in preoperative NMSC circumference.

CONCLUSION

Preoperative lesion circumference is directly proportional to primary closure length and is a better indicator of closure length than preoperative area and short axis for MMS of NMSCs. Closure lengths located on the nasal tip, supratip, or periocular areas are most sensitive to differences in NMSC size. These data might aid Mohs surgeons with preoperative planning for wound reconstruction and patient counseling.

Appropriate use criteria for basal cell carcinoma Mohs surgery at a single center in the face of high-burden skin cancer: a retrospective cohort study

BACKGROUND

Mohs micrographic surgery (MMS) promotes high cure rates, but accessibility to MMS is limited in distinctive realities and countries.

OBJECTIVE

We sought to verify applicable criteria for MMS indication and prioritization regarding basal cell carcinoma (BCC) in the face of various limitations.

METHODS

We analyzed MMS-excised BBC, without patient exclusion, through a retrospective cohort study at a single university center.

RESULTS

Mohs micrographic surgery was performed in 101 BCCs, average size = 5.44 ± 11.91 cm², 56.44% ≥ 20 mm. Most BCCs were in the H-zone (87.13%) and on the nose (52.47%). Histology showed high-risk pattern in most of tumors (69.31%), primary (64.71%), and recurrent (74.0%) BCC. Nasal (p = .01) and recurrent BCC (p = .03) had increased risk for two or more MMS stages. Appropriate use criteria were considered for all cases of BCC removed by a single stage (60.40%), two or more stages (39.60%), and three or more MMS stages (10.89%). The latter two conditions were associated with a higher number of MMS criteria (p = .02; p = .03, respectively).

CONCLUSIONS

All excised BCCs fulfilled criteria for MMS indication, among them recurrent and nasal BCCs stood out. The greater number of criteria may be a predictive factor for subclinical extension and can help prioritize indications for MMS.