Utilisation, effectiveness, and safety of immediate postpartum intrauterine device insertion: a systematic literature review.

BACKGROUND: Intrauterine devices (IUDs) are highly effective contraception. IUDs inserted directly following delivery provide immediate birth control and may decrease unintended pregnancies, including short-interval pregnancies, thereby mitigating health risks and associated economic burden. METHODS: This systematic literature review included published global data on the utilisation, effectiveness, and safety of postpartum intrauterine devices (PPIUDs) of any type. English language articles indexed in MEDLINE, Embase, and Cochrane from January 2010-October 2021 were included. RESULTS: 133 articles met the inclusion criteria (46% interventional studies; 54% observational; n=87 from lower-income countries; n=46 from higher-income countries). PPIUD use was low in higher-income countries (6/10 000 US deliveries in 2013-2016) and varied widely in lower-income countries (2%-46%). Across both higher- and lower-income countries, in most studies (79%), >80% of women with PPIUDs had an IUD in place by 3 months; at 6 and 12 months, 76% and 54% of included studies reported that >80% of women had an IUD in place; reason for discontinuation was infrequently reported. Pregnancies were rare (96 pregnancies across 12 191 women from 37 studies reporting data) and were generally unrelated to device failure, but rather occurred in women no longer using a PPIUD. Expulsions occurred mainly in the early outpatient period and ranged widely (within 3 months: 0-41%). Abnormal bleeding, infections, or perforations were rare. CONCLUSIONS: PPIUDs are safe and effective. Long-term follow-up data are limited. Future research elucidating reasons underlying lack of PPIUD use is warranted.

Development of clinical prediction models for renal and cardiovascular outcomes and mortality in patients with type 2 diabetes and chronic kidney disease using time-varying predictors.

AIMS: To develop a set of prediction models for end-stage kidney disease (ESKD), cardiovascular outcomes, and mortality in patients with type 2 diabetes (T2D) and chronic kidney disease (CKD) using commonly measured clinical variables. METHODS: We studied 1432 participants with T2D and CKD enrolled in the Chronic Renal Insufficiency Cohort, followed for a median period of 7 years. We used Cox proportional-hazards models to model the six outcomes (ESKD, stroke, myocardial infarction (MI), congestive heart failure (CHF), death before ESKD, and all-cause mortality). We internally evaluated these models using concordance and calibration measures. RESULTS: The newly developed six prediction models included 15 predictors: age at diabetes diagnosis, sex, blood pressure, body mass index, hemoglobin A1c, high density lipoprotein cholesterol, urine protein-to-creatinine ratio, estimated glomerular filtration rate, smoking status, and history of stroke, MI, CHF, ESKD, and amputation. The resulting models demonstrated good/strong discrimination (cross-validation C-index range: 0.70 to 0.90) and calibration. CONCLUSIONS: This study provided an internally validated and useful tool for predicting individual adverse outcomes and mortality in patients with T2D and CKD. These models may inform optimal use of targeted health interventions.

An outbreak of SARS-CoV-2 with high mortality in mink (Neovison vison) on multiple Utah farms.

The breadth of animal hosts that are susceptible to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and may serve as reservoirs for continued viral transmission are not known entirely. In August 2020, an outbreak of SARS-CoV-2 occurred on five mink farms in Utah and was associated with high mink mortality (35-55% of adult mink) and rapid viral transmission between animals. The premise and clinical disease information, pathology, molecular characterization, and tissue distribution of virus within infected mink during the early phase of the outbreak are provided. Infection spread rapidly between independently housed animals and farms, and caused severe respiratory disease and death. Disease indicators were most notably sudden death, anorexia, and increased respiratory effort. Gross pathology examination revealed severe pulmonary congestion and edema. Microscopically there was pulmonary edema with moderate vasculitis, perivasculitis, and fibrinous interstitial pneumonia. Reverse transcriptase polymerase chain reaction (RT-PCR) of tissues collected at necropsy demonstrated the presence of SARS-CoV-2 viral RNA in multiple organs including nasal turbinates, lung, tracheobronchial lymph node, epithelial surfaces, and others. Localization of viral RNA by in situ hybridization revealed a more localized infection, particularly of the upper respiratory tract. Whole genome sequencing from multiple mink was consistent with published SARS-CoV-2 genomes with few polymorphisms. The Utah mink SARS-CoV-2 strains fell into Clade GH, which is unique among mink and other animal strains sequenced to date. While sharing the N501T mutation which is common in mink, the Utah strains did not share other spike RBD mutations Y453F and F486L found in nearly all mink from the United States. Mink in the outbreak reported herein had high levels of SARS-CoV-2 in the upper respiratory tract associated with symptomatic respiratory disease and death.

Quantifying the economic burden of unintended pregnancies due to drug-drug interactions with hormonal contraceptives from the United States payer perspective.

Background: In the United States of America (USA), nearly 10 million women use oral contraceptives (OCs). Concomitant administration of certain medications can result in contraceptive failure, and consequently unintended pregnancies due to drug-drug interactions (DDIs). The objective of this analysis was to estimate the economic impact of unintended pregnancies due to DDIs among women of reproductive age using an OC alone or in combination with an enzyme inducer co-medication in the USA from a payer perspective. Methods: A Markov model using a cohort of 1,000 reproductive-age women was developed to estimate costs due to contraceptive failure for OC alone versus OC with concomitant enzyme inducer drugs. All women were assumed to begin an initial state, continuing until experiencing an unintended pregnancy. Unintended pregnancies could result in birth, induced abortion, spontaneous abortion, or ectopic pregnancy. The cohort was analyzed over a time horizon of 1 year with a cycle length of 1 month. Estimates of costs and probabilities of unintended pregnancy outcomes were obtained from the literature. Probabilities from the Markov cohort trace was used to estimate number of pregnancy outcomes. Results: On average, enzyme inducers resulted in 20 additional unintended pregnancies with additional unadjusted and adjusted costs median (range) of USD136,304 (USD57,436-USD320,093) and USD65,146 (USD28,491-USD162,635), respectively. The major component of the direct cost is attributed to the cost of births. Considering the full range of events, DDIs with enzyme inducers could result in 16-25 additional unintended pregnancies and total unadjusted and adjusted costs ranging between USD46,041 to USD399,121 and USD22,839 to USD202,788 respectively. Conclusion: The direct costs associated with unintended pregnancies due to DDIs may be substantial and are potentially avoidable. Greater awareness of DDI risk with oral contraceptives among payers, physicians, pharmacists and patients may reduce unintended pregnancies in at-risk populations.

Rosacea Treatment Satisfaction: Matching Adjusted Indirect Treatment Comparison Analysis of Metronidazole Gel or Cream vs Azelaic Acid Foam.

OBJECTIVE: To assess differences in patient-reported treatment side effects and concerns associated with azelaic acid 15% foam (AAF) vs metronidazole cream (MC) and metronidazole gel (MG). METHODS: This study used matching-adjusted indirect comparison (MAIC) to compare patient-reported outcomes from survey data evaluating rosacea treatments. Outcomes of interest included percentages of patients reporting concerns and side effects and measures of importance of the concerns and tolerability of the side effects. Patients in each analysis (MG vs AAF and MC vs AAF) were matched using stabilized inverse propensity scores. RESULTS: When compared to AAF, MG-treated patients more frequently reported concerns with treatment efficacy (54% vs 4%), application (7% vs 3%), and treatment side effects. MC-treated patients more frequently reported concerns with treatment efficacy (61% vs 5%) and dryness (8% vs 5%). AAF-treated patients more frequently reported concerns with cost of treatment compared with MG (7% vs 1%) and MC (9% vs 4%). Among patients reporting concerns, level of importance associated with these concerns was similar for AAF-treated patients compared with MG- and MC-treated patients. When compared to AAF-treated patients, MG-treated patients more frequently reported side effects of dryness (26% vs 15%) and uneven skin tone (3% vs 0%), and MC-treated patients more frequently reported side effects of burning (7% vs 3%), itching (7% vs 5%), and redness (7% vs 5%). MG- and MC-treated patients indicated greater intolerance for reported side effects than AAF-treated patients. CONCLUSIONS: MG- and MC-treated patients more frequently reported treatment concerns and side effects than AAF-treated patients, and tolerability of those side effects was higher for patients treated with AAF. While treatment cost is a more frequent concern in patients treated with AAF, these patients less frequently reported concerns with treatment efficacy and reported similar or greater tolerance to side effects than patients treated with either MC or MG. J Drugs Dermatol. 2020;19(3): doi:10.36849/JDD.2020.3679.

Concerns and Treatment Satisfaction in Patients Being Treated With Azelaic Acid Foam for Rosacea

Objective: To describe patient characteristics, concerns, side effects, treatment satisfaction, and quality of life (QoL) of rosacea patients currently being treated with monotherapy azelaic acid foam based on patient-reported data. Methods: The study utilized a non-interventional, prospective, observational design. Patients were recruited in the United States and were eligible if the following criteria were met: diagnosed with rosacea by a medical professional, ≥18 years of age, currently receiving monotherapy with azelaic acid foam, and able to provide informed consent. Patients using other topical treatments for rosacea during enrollment were excluded. An online tool administered a survey of 3 questionnaires including the Rosacea Treatment Preference Questionnaire, Treatment Satisfaction with Medicines Questionnaire (SATMED-Q), and Dermatology Life Quality Index (DLQI). The survey collected demographics, clinical characteristics, treatment history, adverse events, and patient-reported outcomes related to treatment with azelaic acid foam and QoL with rosacea. Results: 54 patients met eligibility criteria. Participants were primarily female (90.7%), ranging from 26 to 63 years of age. The most common subtypes reported were erythematotelangiectatic and papulopustular (74.1% each) with 59.3% of participants reporting mild symptoms (16.7% "absent"; 24.1% "moderate") in the 4 weeks before enrollment. The majority reported no concerns (74.1%) with their treatment. The biggest concern was cost (11.1%), with a mean importance score (IS) on a 10-point scale of 9.3. A majority (77.8%) of patients reported no side effects. Side effects reported included dryness (13%; IS: 5.3), stinging (7.4%, IS: 2.5), itching (5.6%; IS: 4.7), or burning (3.7%; IS: 7.0). Global satisfaction (SATMED-Q) mean score was 79.0 and treatment effectiveness mean score was 70.8. QoL impact of rosacea was minimal (mean DLQI score: 2.35). In regression models, increasing dryness was significantly associated with worsening outcomes in SATMED-Q and DLQI. Conclusions: Patient characteristics of the study population closely mirror the distribution of rosacea by gender and subtype as in previous estimates. Findings indicate minimal patient concerns with azelaic acid foam and primarily pertained to cost. Patient-reported side effects were rare. Minor patient-reported side effects and concerns do not appear to affect rosacea-related QoL and medication satisfaction. Compared to a previously conducted study of similar design with patients using metronidazole gel and metronidazole cream, more patients in the current study reported no concerns with their treatment, while the number of patients reporting no side effects, as well as mean SATMED-Q and DLQI scores, were similar. Further research is necessary to directly compare the results of these 2 studies. J Drugs Dermatol. 2019;18(4):381-386.

Patient centered medical homes did not improve access to timely follow-up after ED visit.

BACKGROUND: Patients newly insured through coverage expansion under the Affordable Care Act (ACA) may have difficulty obtaining timely primary care follow-up appointments after emergency department (ED) discharge. We evaluated the association between availability of timely follow-up appointment with practice access improvements, including patient-centered medical home (PCMH) designations or extended-hours appointments. METHODS: We performed a secret-shopper audit of primary care practices in greater New Haven, Connecticut. Two callers, posing as patients discharged from the ED, called these practices requesting follow-up appointments. They followed standardized scripts varying in ED diagnosis (uncontrolled hypertension, acute back pain) and insurance status (commercial, exchange, Medicaid). We linked our findings with data from a previously completed survey that assessed practice characteristics and examined the associations between appointment availability and practice access improvements. RESULTS: Of the 58 included primary care practices, 49 (84.5%) completed both the audit and the survey. Overall, 167/536 calls (31.2%) obtained an appointment in 7days. Practices with PCMH designation were less likely to offer appointments within 7days (23.4% vs. 33.1%, p=0.03). However, callers were more likely to obtain an appointment in 7days from practices offering after-hour appointments (36.3% vs. 27.8%, p=0.04). After adjusting for insurance type, there were no significant associations between practice improvements and 7-day appointment availability or appointment wait time. CONCLUSION: PCMH designation and extended-hours appointments were not associated with improved availability of timely primary care follow-up appointment for discharged ED patients. EDs should engage local clinicians and other stakeholders to strengthen linkage and care transition with outpatient practices.

Pathologists' Use of Second Opinions in Interpretation of Melanocytic Cutaneous Lesions: Policies, Practices, and Perceptions.

BACKGROUND: Research examining the role of second opinions in pathology for diagnosis of melanocytic lesions is limited. OBJECTIVE: To assess current laboratory policies, clinical use of second opinions, and pathologists' perceptions of second opinions for melanocytic lesions. MATERIALS AND METHODS: Cross-sectional data collected from 207 pathologists in 10 US states who diagnose melanocytic lesions. The web-based survey ascertained pathologists' professional information, laboratory second opinion policy, use of second opinions, and perceptions of second opinion value for melanocytic lesions. RESULTS: Laboratory policies required second opinions for 31% of pathologists and most commonly required for melanoma in situ (26%) and invasive melanoma (30%). In practice, most pathologists reported requesting second opinions for melanocytic tumors of uncertain malignant potential (85%) and atypical Spitzoid lesions (88%). Most pathologists perceived that second opinions increased interpretive accuracy (78%) and protected them from malpractice lawsuits (62%). CONCLUSION: Use of second opinions in clinical practice is greater than that required by laboratory policies, especially for melanocytic tumors of uncertain malignant potential and atypical Spitzoid lesions. Quality of care in surgical interventions for atypical melanocytic proliferations critically depends on the accuracy of diagnosis in pathology reporting. Future research should examine the extent to which second opinions improve accuracy of melanocytic lesion diagnosis.

Population-Based Analysis of Histologically Confirmed Melanocytic Proliferations Using Natural Language Processing.

Importance: Population-based information on the distribution of histologic diagnoses associated with skin biopsies is unknown. Electronic medical records (EMRs) enable automated extraction of pathology report data to improve our epidemiologic understanding of skin biopsy outcomes, specifically those of melanocytic origin. Objective: To determine population-based frequencies and distribution of histologically confirmed melanocytic lesions. Design, Setting, and Participants: A natural language processing (NLP)-based analysis of EMR pathology reports of adult patients who underwent skin biopsies at a large integrated health care delivery system in the US Pacific Northwest from January 1, 2007, through December 31, 2012. Exposures: Skin biopsy procedure. Main Outcomes and Measures: The primary outcome was histopathologic diagnosis, obtained using an NLP-based system to process EMR pathology reports. We determined the percentage of diagnoses classified as melanocytic vs nonmelanocytic lesions. Diagnoses classified as melanocytic were further subclassified using the Melanocytic Pathology Assessment Tool and Hierarchy for Diagnosis (MPATH-Dx) reporting schema into the following categories: class I (nevi and other benign proliferations such as mildly dysplastic lesions typically requiring no further treatment), class II (moderately dysplastic and other low-risk lesions that may merit narrow reexcision with <5-mm margins), class III (eg, melanoma in situ and other higher-risk lesions warranting reexcision with 5-mm to 1-cm margins), and class IV/V (invasive melanoma requiring wide reexcision with ≥1-cm margins and potential adjunctive therapy). Health system cancer registry data were used to define the percentage of invasive melanoma cases within MPATH-Dx class IV (stage T1a) vs V (≥stage T1b). Results: A total of 80 368 skin biopsies, performed on 47 529 patients, were examined. Nearly 1 in 4 skin biopsies were of melanocytic lesions (23%; n = 18 715), which were distributed according to MPATH-Dx categories as follows: class I, 83.1% (n = 15 558); class II, 8.3% (n = 1548); class III, 4.5% (n = 842); class IV, 2.2% (n = 405); and class V, 1.9% (n = 362). Conclusions and Relevance: Approximately one-quarter of skin biopsies resulted in diagnoses of melanocytic proliferations. These data provide the first population-based estimates across the spectrum of melanocytic lesions ranging from benign through dysplastic to malignant. These results may serve as a foundation for future research seeking to understand the epidemiology of melanocytic proliferations and optimization of skin biopsy utilization.

The influence of tumor regression, solar elastosis, and patient age on pathologists' interpretation of melanocytic skin lesions.

It is not known whether patient age or tumor characteristics such as tumor regression or solar elastosis influence pathologists' interpretation of melanocytic skin lesions (MSLs). We undertook a study to determine the influence of these factors, and to explore pathologist's characteristics associated with the direction of diagnosis. To meet our objective, we designed a cross-sectional survey study of pathologists' clinical practices and perceptions. Pathologists were recruited from diverse practices in 10 states in the United States. We enrolled 207 pathologist participants whose practice included the interpretation of MSLs. Our findings indicated that the majority of pathologists (54.6%) were influenced toward a less severe diagnosis when patients were <30 years of age. Most pathologists were influenced toward a more severe diagnosis when patients were >70 years of age, or by the presence of tumor regression or solar elastosis (58.5%, 71.0%, and 57.0%, respectively). Generally, pathologists with dermatopathology board certification and/or a high caseload of MSLs were more likely to be influenced, whereas those with more years' experience interpreting MSL were less likely to be influenced. Our findings indicate that the interpretation of MSLs is influenced by patient age, tumor regression, and solar elastosis; such influence is associated with dermatopathology training and higher caseload, consistent with expertise and an appreciation of lesion complexity.

Variation among pathologists' treatment suggestions for melanocytic lesions: A survey of pathologists.

BACKGROUND: The extent of variability in treatment suggestions for melanocytic lesions made by pathologists is unknown. OBJECTIVE: We investigated how often pathologists rendered suggestions, reasons for providing suggestions, and concordance with national guidelines. METHODS: We conducted a cross-sectional survey of pathologists. Data included physician characteristics, experience, and treatment recommendation practices. RESULTS: Of 301 pathologists, 207 (69%) from 10 states (California, Connecticut, Hawaii, Iowa, Kentucky, Louisiana, New Jersey, New Mexico, Utah, and Washington) enrolled. In all, 15% and 7% reported never and always including suggestions, respectively. Reasons for offering suggestions included improved care (79%), clarification (68%), and legal liability (39%). Reasons for not offering suggestions included referring physician preference (48%), lack of clinical information (44%), and expertise (29%). Training and caseload were associated with offering suggestions (P < .05). Physician suggestions were most consistent for mild/moderate dysplastic nevi and melanoma. For melanoma in situ, 18 (9%) and 32 (15%) pathologists made suggestions that undertreated or overtreated lesions based on National Comprehensive Cancer Network (NCCN) guidelines, respectively. For invasive melanoma, 14 (7%) pathologists made treatment suggestions that undertreated lesions based on NCCN guidelines. LIMITATIONS: Treatment suggestions were self-reported. CONCLUSIONS: Pathologists made recommendations ranging in consistency. These findings may inform efforts to reduce treatment variability and optimize patterns of care delivery for patients.

Patient-reported outcomes of azelaic acid foam 15% for patients with papulopustular rosacea: secondary efficacy results from a randomized, controlled, double-blind, phase 3 trial.

Patient-reported treatment outcomes are important for evaluating the impact of drug therapies on patient experience. A randomized, double-blind, vehicle-controlled, parallel-group, multicenter, phase 3 study was conducted in 961 participants to assess patient perception of efficacy, utility, and effect on quality of life (QOL) of an azelaic acid (AzA) 15% foam formulation for the treatment of papulopustular rosacea (PPR). Secondary end points included patient-reported global assessment of treatment response, global assessment of tolerability, and opinion on cosmetic acceptability and practicability of product use. Quality of life assessments included the Dermatology Quality of Life Index (DLQI) and Rosacea Quality of Life Index (RosaQOL). Self-reported global assessment of treatment response favored AzA foam over vehicle foam (P<.001), with 57.2% of the AzA foam group reporting excellent or good improvement versus 44.7% in the vehicle foam group. Tolerability was rated excellent or good in 67.8% of the AzA foam group versus 78.2% of the vehicle foam group. Mean overall DLQI scores at end of treatment (EoT) were improved (P=.018) in favor of the AzA foam group compared with the vehicle foam group. Both treatment groups showed improvements in RosaQOL. Treatment with AzA foam was associated with improved QOL and meaningful reductions in the patient-perceived burden of PPR, which correlates with earlier reported primary end points of this study and supports the inclusion of patient perspectives in studies evaluating the effects of topical dermatologic treatments.

Resident perspectives on a dermatology Quality Improvement curriculum: the University of Colorado experience.

The Centers for Medicare and Medicaid Services (CMS) have prioritized the objective of optimizing quality healthcare though quality improvement initiatives, yet research on dermatology-specific QI programs and their perceptions among dermatology residents remains limited. We explore residents' opinions of a dermatology-specific QI scholarly project curriculum implemented at University of Colorado Denver (UCD) in 2010 and also evaluate residents' attitudes regarding the value of this curriculum in aiding them to meet ACGME core competencies.

Evaluation of the Melanocytic Pathology Assessment Tool and Hierarchy for Diagnosis (MPATH-Dx) classification scheme for diagnosis of cutaneous melanocytic neoplasms: Results from the International Melanoma Pathology Study Group.

BACKGROUND: Pathologists use diverse terminology when interpreting melanocytic neoplasms, potentially compromising quality of care. OBJECTIVE: We sought to evaluate the Melanocytic Pathology Assessment Tool and Hierarchy for Diagnosis (MPATH-Dx) scheme, a 5-category classification system for melanocytic lesions. METHODS: Participants (n = 16) of the 2013 International Melanoma Pathology Study Group Workshop provided independent case-level diagnoses and treatment suggestions for 48 melanocytic lesions. Individual diagnoses (including, when necessary, least and most severe diagnoses) were mapped to corresponding MPATH-Dx classes. Interrater agreement and correlation between MPATH-Dx categorization and treatment suggestions were evaluated. RESULTS: Most participants were board-certified dermatopathologists (n = 15), age 50 years or older (n = 12), male (n = 9), based in the United States (n = 11), and primary academic faculty (n = 14). Overall, participants generated 634 case-level diagnoses with treatment suggestions. Mean weighted kappa coefficients for diagnostic agreement after MPATH-Dx mapping (assuming least and most severe diagnoses, when necessary) were 0.70 (95% confidence interval 0.68-0.71) and 0.72 (95% confidence interval 0.71-0.73), respectively, whereas correlation between MPATH-Dx categorization and treatment suggestions was 0.91. LIMITATIONS: This was a small sample size of experienced pathologists in a testing situation. CONCLUSION: Varying diagnostic nomenclature can be classified into a concise hierarchy using the MPATH-Dx scheme. Further research is needed to determine whether this classification system can facilitate diagnostic concordance in general pathology practice and improve patient care.

Use of Digital Whole Slide Imaging in Dermatopathology.

Digital whole slide imaging (WSI) is an emerging technology for pathology interpretation, with specific challenges for dermatopathology, yet little is known about pathologists' practice patterns or perceptions regarding WSI for interpretation of melanocytic lesions. A national sample of pathologists (N = 207) was recruited from 864 invited pathologists from ten US states (CA, CT, HI, IA, KY, LA, NJ, NM, UT, and WA). Pathologists who had interpreted melanocytic lesions in the past year were surveyed in this cross-sectional study. The survey included questions on pathologists' experience, WSI practice patterns and perceptions using a 6-point Likert scale. Agreement was summarized with descriptive statistics to characterize pathologists' use and perceptions of WSI. The majority of participating pathologists were between 40 and 59 years of age (62%) and not affiliated with an academic medical center (71%). Use of WSI was seen more often among dermatopathologists and participants affiliated with an academic medical center. Experience with WSI was reported by 41%, with the most common type of use being for education and testing (CME, board exams, and teaching in general, 71%), and clinical use at tumor boards and conferences (44%). Most respondents (77%) agreed that accurate diagnoses can be made with this technology, and 59% agreed that benefits of WSI outweigh concerns. However, 78% of pathologists reported that digital slides are too slow for routine clinical interpretation. The respondents were equally split as to whether they would like to adopt WSI (49%) or not (51%). The majority of pathologists who interpret melanocytic lesions do not use WSI, but among pathologists who do, use is largely for CME, licensure/board exams, and teaching. Positive perceptions regarding WSI slightly outweigh negative perceptions. Understanding practice patterns with WSI as dissemination advances may facilitate concordance of perceptions with adoption of the technology.

Grading of atypia in genital skin lesions: routine microscopic evaluation and use of p16 immunostaining.

BACKGROUND: p16 immunostaining has been used to aid and improve the histopathologic evaluation of equivocal cervical lesions with associated low-grade or high-grade dysplasia. However, the utility of p16 immunostaining in the diagnosis of atypical genital skin lesions remains debatable. METHODS: We conducted a cross-sectional study of genital skin lesions with varying degrees of atypia. Four pathologists assessed lesional atypia and interpreted hematoxylin and eosin (H&E) staining and p16 immunostaining without knowledge of original diagnosis. Our primary outcomes were diagnostic agreement and test performance of p16 immunostaining compared to consensus H&E diagnosis. RESULTS: Our sample was comprised of 23 cases of atypical genital skin lesions. p16 immunostaining was negative in all cases of reactive atypia (n = 3) and the majority (n = 7 of 8; 88%) of low-grade squamous intraepithelial lesions (LSILs). The majority (n = 10 of 12; 83%) of high-grade squamous intraepithelial lesions (HSIL) were p16 positive. Diagnostic agreement for histopathologic assessment using H&E staining was moderate (kappa = 0.44), while inter-observer agreement of p16 immunostaining was excellent (kappa = 0.87). Compared to consensus diagnosis using H&E staining, p16 immunostaining performed well (sensitivity 83.3%; specificity 90.9%). CONCLUSIONS: p16 immunostaining may be a useful adjunctive marker for assessing dysplasia in genital skin lesions and increasing diagnostic agreement among pathologists.