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.

Treatment of extramammary Paget's disease with imiquimod in a real-life setting: a multicenter retrospective analysis in Spain.

BACKGROUND: Topical imiquimod has shown to be an effective treatment for EMPD, although available evidence supporting its use is based on case reports and small series of patients. OBJECTIVES: To investigate the therapeutic outcomes and analyze potential clinico-pathological factors associated with imiquimod response in a large cohort of EMPD patients. METHODS: Retrospective chart review of 125 EMPD patients treated with imiquimod at 20 Spanish tertiary-care hospitals. RESULTS: During the study period, patients received 134 treatment regimens with imiquimod, with 70 (52.2%) cases achieving complete response (CR), 41 (30.6%) partial response and 23 (17.2%) no response. The cumulative CR rates at 24 and 48 weeks of treatment were 46.3% and 71.8%, respectively, without significant differences between first-time and previously treated EMPD. Larger lesions (≥6 cm; p = 0.038) and EMPD affecting >1 anatomical site (p = 0.002) were significantly associated with a worse treatment response. However, the CR rate did not differ significantly by the number of treatment applications (≤4 vs. > 4 times/week; p = 0.112). Among patients who achieved CR, 30 (42.9%) developed local recurrences during a mean follow-up period of 36 months, with an estimated 3 and 5-year recurrence free-survival of 55.7% and 36.4%, respectively. CONCLUSIONS: Imiquimod appears as an effective therapeutic alternative for both first-line and previously treated EMPD lesions. However, a less favorable therapeutic response could be expected in larger lesions and those affecting >1 anatomical site. Based on our results, a 3-4 times weekly regimen of imiquimod with a treatment duration of at least 6 months could be considered an appropriate therapeutic strategy for EMPD patients.

Therapeutic outcomes and survival analysis of Extramammary Paget's disease: A multicentre retrospective study of 249 patients.

BACKGROUND: Evidence regarding long-term therapeutic outcomes and disease-specific survival (DSS) in Extramammary Paget's disease (EMPD) is limited. OBJECTIVES: To assess the DSS and outcomes of surgical and nonsurgical therapeutic modalities in a large cohort of EMPD patients. METHODS: Retrospective chart review of EMPD patients from 20 Spanish tertiary care hospitals. RESULTS: Data on 249 patients with a median follow-up of 60 months were analyzed. The estimated 5-, 10-, and 15-year DSS was 95.9%, 92.9%, and 88.5%, respectively. A significantly lower DSS was observed in patients showing deep dermal invasion (≥1 mm) or metastatic disease (P < .05). A ≥50% reduction in EMPD lesion size was achieved in 100% and 75.3% of patients treated with surgery and topical therapies, respectively. Tumor-free resection margins were obtained in 42.4% of the patients after wide local excision (WLE). The 5-year recurrence-free survival after Mohs micrographic surgery (MMS), WLE with tumor-free margins, WLE with positive margins, radiotherapy, and topical treatments was 63.0%, 51.4%, 20.4%, 30.1%, and 20.8%, respectively. LIMITATIONS: Retrospective design. CONCLUSIONS: EMPD is usually a chronic condition with favorable prognosis. MMS represents the therapeutic alternative with the greatest efficacy for the disease. Recurrence rates in patients with positive margins after WLE are similar to the ones observed in patients treated with topical agents.

A Novel Approach to the Reconstruction of a Large Surgical Defect in the Cheek.

BACKGROUND: Large lateral cheek defects can be challenging to reconstruct. Several approaches to reconstruction of these defects have been reported. In the case presented here, we describe an alternative reconstruction method for this type of surgical defect. Detailed Case Description: We present one patient with a large basal cell carcinoma on his lateral left cheek who underwent a complete tumor removal by Mohs surgery and was left with a defect 6 × 6 cm in size. This large defect was closed by performing a double transposition flap under local anesthesia. RESULTS: Both flaps survived with no loss. The immediate and long-term outcomes were satisfactory, preserving functionality with good cosmetic results. CONCLUSIONS: Cheek defect reconstruction with the double transposition flap is simple and reliable, with good aesthetic and functional outcomes. It may be considered as an alternative reconstructive method for this type of defect, in an appropriate context.

Real-World Experience with Vismodegib on Advanced and Multiple BCCs: Data from the RELIVIS Study.

BACKGROUND: Vismodegib is approved for advanced cases of basal cell carcinomas not amenable to surgery or radiotherapy. Large studies on the use of vismodegib in clinical practice are scarce. OBJECTIVES: The main objective of the study was to analyse the evolution and therapeutic management of relapses and lack of response in patients who had received vismodegib for locally advanced and/or multiple basal cell carcinomas in a real-life multicentre setting. METHODS: This nationwide retrospective study collected data on patients treated with vismodegib in 15 specialized centres. We included patients who first received vismodegib until intolerable toxicity, maximum response, or progressive disease. Exploratory research variables referred to patient and tumour characteristics, vismodegib effectiveness and safety, relapse rate and management, and mortality. A multivariable logistic regression model was used to identify predictors of complete clinical response. RESULTS: 133 patients with advanced BCC were included in the registry. The objective response rate (ORR) was 77.5% and nearly half of the patients (45.9%) achieved complete remission. Long-term information and detailed information of subsequent treatments after a regime of vismodegib was available for 115 patients. Only 34% of the patients in this group were subsequently treated with other therapies or vismodegib rechallenge. Sixty-nine percent of the patients who had shown a complete remission with vismodegib remained free of recurrence while 30.7% relapsed. Almost half of the patients who received additional therapies after the first course of vismodegib achieved complete tumour remission. Three and 2 out of 9 patients who were rechallenged with vismodegib achieved complete and partial responses, respectively, with an ORR of 55.5%. CONCLUSION: Our study confirms efficacy of vismodegib in routine clinical practice. The risk of recurrence after achieving complete response with vismodegib was lower than previous reports. Rechallenge with vismodegib is feasible and most patients responded to re-treatment.

Liver elastography can predict degree of advanced fibrosis for autoimmune hepatitis in biochemical remission.

Background and Aim: The aim was to analyze the concordance of liver stiffness measurement (LSM) either by transient elastography (TE) or ARFI with liver biopsy in autoimmune hepatitis (AIH) patients with biochemical remission and to identify those with histological remission. Liver biopsy is still the golden standard for AIH diagnosis. However, it is an invasive procedure and these patients, most of the time, require many biopsies, so it would be valuable to search for noninvasive method that could select all these patients and keep under observation. Methods: Thirty-three patients with AIH were submitted for liver biopsy to evaluate histological remission after at least 18 months of normal aminotransferases. The efficiency of LSM and fibrosis stages was tested by a receiver operating characteristic curve analysis (AUROC). Results: One patient (3%) was F0, 6 (18.2%) were F1, 8 (24.2%) were F2, 10 (30.3%) were F3, and 8 (24.2%) were F4, according to METAVIR. Thirteen of thirty-three (39.4%) patients did not achieve histological remission. AUROC for F4 stage was 0.83 (IC: 0.76-0.99) for TE and 0.78 (IC: 0.65-0.95) for ARFI. Optimal LSM cutoff values were 12.3 kPa (Se = 87.5%, Sp = 88%) for TE and 1.65 m/s (Se = 87.5%, Sp = 76%) for ARFI. The tests were unable to differentiate patients with histological activity from those in histological remission (P < 0.05). Conclusion: TE and ARFI accurately identify liver fibrosis by METAVIR score in AIH patients with biochemical remission. No cutoff value was detected to indicate whether the patient achieved histological remission.

Phylogenetic analysis reveals that the H5N1 avian influenza A outbreak in poultry in Ecuador in November 2022 is associated with the highly pathogenic clade 2.3.4.4b.

The ongoing H5N1 outbreak in the Americas caused by clade 2.3.4.4 is causing unprecedented impact in poultry and wild birds. In November 2022, a highly pathogenic avian influenza A outbreak was declared in poultry in Ecuador, affecting more than 1.1 million heads of poultry in two farms by February 2023. Phylogenetic analysis shows that the virus clade is 2.3.4.4b, and to the best of our knowledge, this is the first scientific publication reporting this clade in South America.

Prognostic factors for satellitosis or in-transit metastasis in cutaneous squamous cell carcinoma: A multicentric cohort study.

BACKGROUND: Satellitosis or in-transit metastasis (S-ITM) has clinical outcomes comparable to node-positivity in cutaneous squamous cell carcinoma (cSCC). There is a need to stratify the risk groups. OBJECTIVE: To determine which prognostic factors of S-ITM confer an increased risk of relapse and cSCC-specific-death. METHODS: A retrospective, multicenter cohort study. Patients with cSCC developing S-ITM were included. Multivariate competing risk analysis evaluated which factors were associated with relapse and specific death. RESULTS: Of a total of 111 patients with cSCC and S-ITM, 86 patients were included for analysis. An S-ITM size of ≥20 mm, >5 S-ITM lesions, and a primary tumor deep invasion was associated with an increased cumulative incidence of relapse (subhazard ratio [SHR]: 2.89 [95% CI, 1.44-5.83; P = .003], 2.32 [95% CI, 1.13-4.77; P = .021], and 2.863 [95% CI, 1.25-6.55; P = .013]), respectively. Several >5 S-ITM lesions were also associated with an increased probability of specific death (SHR: 3.48 [95% CI, 1.18-10.2; P = .023]). LIMITATIONS: Retrospective study and heterogeneity of treatments. CONCLUSION: The size and the number of S-ITM lesions confer an increased risk of relapse and the number of S-ITM an increased risk of specific-death in patients with cSCC presenting with S-ITM. These results provide new prognostic information and can be considered in the staging guidelines.

Development and validation of a model to predict complex Mohs micrographic surgery in clinical practice: REGESMOSH scale.

INTRODUCTION: There is still a need to develop a simple algorithm to identify patients likely to need complex Mohs micrographic surgery (MMS) and optimize MMS schedule. The main objectives of this study are to identify factors associated with a complex MMS and develop a predictor model of the number of stages needed in surgery and the need for a complex closure. MATERIALS AND METHODS: A nationwide prospective cohort study (REGESMOHS, the Spanish Mohs surgery registry) was conducted including all patients with a histological diagnosis of basal cell carcinoma (BCC). Factors related to three or more stages and a complex closure (that needing a flap and/or a graft) were explored and predictive models were constructed and validated to construct the REGESMOSH scale. RESULTS: A total of 5226 patients that underwent MMS were included in the REGESMOHS registry, with 4402 (84%) having a histological diagnosis of BCC. A total of 3689 (88.9%) surgeries only needed one or two stages and 460 (11.1%) required three or more stages. A model to predict the need for three or more stages included tumour dimension, immunosuppression, recurrence, location in risk areas, histological aggressiveness and previous surgery. Regarding the closure type, 1616 (38.8%) surgeries were closed using a non-complex closure technique and 2552 (61.2%) needed a complex closure. A model to predict the need for a complex closure included histological aggressiveness, evolution time, patient age, maximum tumour dimension and location. CONCLUSION: We present a model to predict MMS needing ≥3 stages and a complex closure based on epidemiological and clinical data validated in a large population (with real practice variability) including different centres that could be easily implemented in clinical practice. This model could be used to optimize surgery schedule and properly inform patients about the surgery duration.

Complications Associated with Mohs Micrographic Surgery: Data from the Nationwide Prospective Cohort REGESMOHS.

BACKGROUND: Large prospective studies on the safety of Mohs micrographic (MMS) surgery are scarce, and most focus on a single type of surgical adverse event. Mid-term scar alterations and functional loss have not been described. OBJECTIVES: To describe the risk of MMS complications and the risk factors for them. METHODS: A nationwide prospective cohort collected all adverse events on consecutive patients in 22 specialised centres. We used multilevel mixed-effects logistic regression to find out factors associated with adverse events. RESULTS: 5,017 patients were included, with 14,421 patient-years of follow-up. 7.0% had some perioperative morbidity and 6.5% had mid-term and scar-related complications. The overall risk of complications was mainly associated with use of antiaggregant/anticoagulant and larger tumours, affecting deeper structures, not reaching a tumour-free border, and requiring complex repair. Age and outpatient setting were not linked to the incidence of adverse events. Risk factors for haemorrhage (0.9%) were therapy with antiaggregant/anticoagulants, tumour size, duration of surgery, and unfinished surgery. Wound necrosis (1.9%) and dehiscence (1.0%) were associated with larger defects and complex closures. Immunosuppression was only associated with an increased risk of necrosis. Surgeries reaching deeper structures, larger tumours and previous surgical treatments were associated with wound infection (0.9%). Aesthetic scar alterations (5.4%) were more common in younger patients, with larger tumours, in H-area, and in flap and complex closures. Risk factors for functional scar alterations (1.7%) were the need for general anaesthesia, larger tumours that had received previous surgery, and flaps or complex closures. CONCLUSIONS: MMS shows a low risk of complications. Most of the risk factors for complications were related to tumour size and depth, and the resulting need for complex surgery. Antiaggregant/anticoagulant intake was associated with a small increase in the risk of haemorrhage, that probably does not justify withdrawal. Age and outpatient setting were not linked to the risk of adverse events.

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 patient-years 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.

Consensus-Based Recommendations on the Prevention of Squamous Cell Carcinoma in Solid Organ Transplant Recipients: A Delphi Consensus Statement.

IMPORTANCE: There is a paucity of evidence to guide physicians regarding prevention strategies for cutaneous squamous cell carcinoma (CSCC) in solid organ transplant recipients (SOTRs). OBJECTIVE: To examine the development and results of a Delphi process initiated to identify consensus-based medical management recommendations for prevention of CSCC in SOTRs. EVIDENCE REVIEW: Dermatologists with more than 5 years' experience treating SOTRs were invited to participate. A novel actinic damage and skin cancer index (AD-SCI), consisting of 6 ordinal stages corresponding to an increasing burden of actinic damage and CSCC, was used to guide survey design. Three sequential web-based surveys were administered from January 1, 2019, to December 31, 2020. Pursuant to Delphi principles, respondents thoroughly reviewed all peer responses between rounds. Supplemental questions were also asked to better understand panelists' rationale for their responses. FINDINGS: The Delphi panel comprised 48 dermatologists. Respondents represented 13 countries, with 27 (56%) from the US. Twenty-nine respondents (60%) were Mohs surgeons. Consensus was reached with 80% or higher concordance among respondents when presented with a statement, question, or management strategy pertaining to prevention of CSCC in SOTRs. A near-consensus category of 70% to less than 80% concordance was also defined. The AD-SCI stage-based recommendations were established if consensus or near-consensus was achieved. The panel was able to make recommendations for 5 of 6 AD-SCI stages. Key recommendations include the following: cryotherapy for scattered actinic keratosis (AK); field therapy for AK when grouped in 1 anatomical area, unless AKs are thick in which case field therapy and cryotherapy were recommended; combination lesion directed and field therapy with fluorouracil for field cancerized skin; and initiation of acitretin therapy and discussion of immunosuppression reduction or modification for patients who develop multiple skin cancers at a high rate (10 CSCCs per year) or develop high-risk CSCC (defined by a tumor with approximately ≥20% risk of nodal metastasis). No consensus recommendation was achieved for SOTRs with a first low risk CSCC. CONCLUSIONS AND RELEVANCE: Physicians may consider implementation of panel recommendations for prevention of CSCC in SOTRs while awaiting high-level-of-evidence data. Additional clinical trials are needed in areas where consensus was not reached.

Mohs micrographic surgery in dermatofibrosarcoma protuberans: Rate and risk factors for recurrence in a prospective cohort study from the Spanish Registry of Mohs Surgery (REGESMOHS) and review of the literature.

Characterization of patients, surgery procedures and the risk factors for dermatofibrosarcoma protuberans (DFSP) recurrences is poorly defined. In this study, we aimed to describe the demographics, tumor characteristics and interventions of DFSP treated with Mohs micrographic surgery (MSS) to determine the rate and risk factors for recurrence. Data were collected from REGESMOHS, a nationwide prospective cohort study of patients treated with MMS in Spain. From July 2013 to February 2020, 163 patients with DFSP who underwent MMS were included. DFSP was mostly located on trunk and extremities. Recurrent tumors had deeper tumor invasion and required higher number of MMS stages. Paraffin MMS was the most frequently used technique. Overall recurrence rate was 0.97 cases/100 person-years (95% IC = 0.36-2.57). No differences were found in epidemiological, tumor, surgery characteristics or surgical technique (frozen or paraffin MMS [p = 0.6641]) in terms of recurrence. Median follow-up time was 28.6 months with 414 patient-years of follow-up. In conclusion, we found an overall low recurrence rate of DFSP treated with MMS. None of the studied risk factors, including MMS techniques, was associated with higher risk for recurrence.

Snapshot of symptoms of advanced cervical cancer patients referred to the palliative care service in a cancer center in Mexico.

OBJECTIVE: To report the clinical and demographic characteristics of patients with advanced cervical cancer referred to the palliative care service (PC) at a major cancer center in Mexico. METHODS: This is a retrospective cohort study of patients with advanced cervical cancer referred to the PC of INCan, between January 2011 and December 2015. Demographic and clinical characteristics at the time of admission to the INCan, time to referral to PC, initial Edmonton Symptom Assessment System evaluation, and follow up were recorded. RESULTS: In all, 359 patients were included, median age 51 years, predominantly poor with low education. Most patients 322 (90%) received tumor-specific treatment; presence of nephrostomies and other tumor-related complication was frequent. Median time to referral was 335 days, more than 180 (50%) had five or more symptoms, pain and fatigue were the most prevalent. CONCLUSION: Women with advanced cervical cancer have a high burden of symptoms; PC is only considered at the end of life. Efforts for an early referral to PC should be made.

State of the art of Mohs surgery for rare cutaneous tumors in the Spanish Registry of Mohs Surgery (REGESMOHS).

BACKGROUND: The use of Mohs micrographic surgery (MMS) for rare cutaneous tumors is poorly defined. We aim to describe the demographics, tumor presentation and topography, surgery characteristics and complications of MMS for rare cutaneous tumors in a national registry. METHODS: Prospective cohort study of patients treated with MMS in Spain between July 2013 and June 2018. The inclusion criteria were patients with cutaneous tumors with final diagnosis different from basal cell carcinoma, squamous cell carcinoma, dermatofibrosarcoma protuberans, or any kind of melanoma. RESULTS: Five thousand and ninety patients were recorded in the registry, from which only 73 tumors (1.4%) fulfilled the inclusion criteria: atypical fibroxanthoma (18), microcystic adnexal carcinoma (10), extramammary Paget's disease (7), Merkel cell carcinoma (5), dermatofibroma (4), trichilemmal carcinoma (4), desmoplastic trichoepithelioma (4), sebaceous carcinoma (3), leiomyosarcoma (2), porocarcinoma (2), angiosarcoma (2), trichoblastoma (1), superficial acral fibromyxoma (1), and others (10). No intra-surgery morbidity was registered. Postsurgery complications appeared in six patients (9%) and were considered mild. Median follow-up time was 0.9 years during which three Merkel cell carcinomas, one angiosarcoma, one microcystic adnexal carcinoma, and four others recurred (12.3%). CONCLUSION: This national registry shows that rare cutaneous tumors represent a negligible part of the total MMS performed in our country with a low complication rate.

Tumor anexial de probable origen Wolffiano en mujer joven con antecedente de cáncer de mama / Adnexal tumor of probable Wolffian origin in a young woman with a history of breast cancer

El tumor anexial de probable origen wolffiano (FATWO) es un tumor raro que se presenta en las estructuras derivadas de los remanentes de los conductos mesonéfricos, y suele ser asintomático. Es un tumor de comportamiento benigno en la mayor parte de casos aunque se han descrito recidivas y metástasis. Presentamos el caso de una mujer con antecedente de cáncer de mama que presentó tumor de origen Wolffiano como hallazgo casual al someterse a una doble anexectomía y revisamos literatura basada en diagnóstico y tratamiento de esta entidad. El tratamiento aceptado actualmente es la histerectomía y doble anexectomía. Existen pocos casos documentados en la bibliografía por la rareza de esta patología

The adnexal tumor of probable Wolffian origin (FATWO) is a rare tumor presented in the structures derived from the remnants of the mesonephric ducts ( Wolffian ducts) and it is usually asymptomatic. In most of the cases FATWO has benign features. Although it has being cases reporting as recurrences and metastasis. We are presenting the case of a woman with a history of breast cancer that presented the tumor of Wolfian origin like a casual find when she was submitted to a bilateral salpingo-oophorectomy procedure. There are few documented cases and literature to review based on diagnosing and treatment of this entity because of the rarity of this disease

Basal cell carcinoma treated with Mohs micrographic surgery in young Ibero-American patients.

BACKGROUND: The incidence of basal cell carcinoma (BCC) in younger individuals has increased in recent decades. However, the characteristics of BCCs in this population, especially in Ibero-Latin American countries, have not been completely defined. OBJECTIVE: To describe the demographic, clinical, and histopathological characteristics of BCCs in patients younger than 40 treated with Mohs Micrographic Surgery (MMS). MATERIALS AND METHODS: A multicenter, retrospective study conducted between January 2009 and December 2014, in five Ibero-American countries, included biopsy-proven BCCs in patients younger than 40 that were treated with MMS. Demographic, clinical, histopathological, and surgical characteristics were described. RESULTS: The study included 301 tumors in 241 patients, of whom 61% were female. The most common Fitzpatrick phototype was III. The most common histological subtypes were nodular (37.5%) and infiltrative (18.9%). Perineural invasion was encountered in 1.7%, and tumor clearance was achieved in 87.4% within two stages of MMS. CONCLUSIONS: This is the first Ibero-Latin American transnational study describing the characteristics of BCCs in young patients treated with MMS. Despite darker skin phototypes in this population, BCCs can occur in early ages and may present with aggressive features. Therefore, MMS may be considered an appropriate first-line treatment option in this population.

Differences of Mohs micrographic surgery in basal cell carcinoma versus squamous cell carcinoma.

BACKGROUND: The two main tumors treated with Mohs micrographic surgery (MMS) are basal cell carcinoma (BCC) and squamous cell carcinoma (SCC). There are no studies analyzing whether MMS is different when treating these two types of tumors. OBJECTIVE: We aim to compare the characteristics of the patients, the tumors, and MMS, and first-year follow-up of MMS in BCC and SCC. METHODS: REGESMOHS is a prospective cohort study of patients treated with MMS. The participating centers are 19 Spanish hospitals where at least one MMS is performed per week. Data on characteristics of the patients, tumors, and surgery were recorded. The follow-up was done with two visits: the first visit within 1 month after surgery and the second one within the first year. RESULTS: From July 2013 to April 2017, a total of 2,669 patients who underwent MMS were included in the registry. Of them, 2,448 (93%) were diagnosed with BCC, and 181 (7%) were diagnosed with SCC. Patients with SCC were older than those with BCC (median age 73 years vs. 68 years) and presented immunosuppression more frequently. The tumor size was significantly larger in the SCC group. Regarding surgery, deeper invasion was more frequent in SCC, resulting in larger defects. Despite this, SCC did not require more stages to get clear margins or more time in the operating room. Incomplete Mohs was more frequent in the SCC group (6%) than in the BCC group (2%). The incidence of perioperative complications was higher when treating SCC. There were more relapses in the first-year follow-up in the SCC group. CONCLUSION: There are significant differences when comparing MMS in BCC and SCC. Knowledge of these differences can help to prepare the patient and plan the surgery, optimizing results.