Long-term outcomes after amputation and sentinel node biopsy for subungual melanoma: A single-institution series

BACKGROUND

Subungual melanoma (SUM) is a rare tumor with historically poor outcomes. Thus, the benefit of proximal versus distal amputation in SUM remains unclear.

METHODS

We performed a retrospective review of our prospectively-maintained institutional melanoma database, including SUM and non-subungual acral melanoma (AM) patients who underwent sentinel lymph node biopsy (SLNB) between 1999 and 2022. All SUMs had distal joint or proximal amputations. Primary endpoints were overall survival (OS) and recurrence free survival (RFS). Kaplan-Meier estimates, and Cox univariate and multivariate analyses were performed. Tests were repeated on propensity score matched (PSM) populations in a 2:1 ratio.

RESULTS

123 patients underwent resection with SLNB for SUM (n ​= ​27) and AM (n ​= ​96). Median follow-up was 9.2 years. Unadjusted median OS was 149.1 months for AM and 198.1 months for SUM. In the PSM comparison, median OS and RFS remained comparable between SUM and AM (149.5 months versus 198.1 months; p ​= ​0.612). Sentinel node positivity was associated with significantly worse overall survival outcome (Hazard Ratio 5.49; CI (1.59-18.97), p ​= ​0.007). In the PSM population, male sex was also associated with a significant hazard of death (HR 3.00, CI (1.03-8.71), p ​= ​0.043). Proximal amputations were associated with significantly worse OS (p ​< ​0.002) and RFS (p ​< ​0.01) compared to distal amputations in SUM.

CONCLUSION

SUM was well-treated with distal amputations, and had better OS and RFS compared to SUM treated with proximal amputations. Sentinel lymph node status is an important prognostic factor for SUMs and AMs. SUMs can be treated similarly to AMs with comparably good long-term outcomes.

Onychocytic Matricoma: A Clinical, Dermoscopic, and Pathological Analysis of 14 Cases

ABSTRACT

Onychocytic matricoma (OCM) is a benign neoplasm of the nail matrix. Only 18 cases of this tumor have been reported in the literature to date. We retrospectively analyzed the clinical features of 14 patients with OCM. The most common clinical feature was longitudinal xanthopachyonychia (n = 9), followed by longitudinal leukopachyonychia (=3) and longitudinal pachymelanonychia (n = 2). The most common clinical findings identified following dermoscopy and analysis at high magnification of classical photographs were free-edge thickening of the nail plate without pitting (n = 14), longitudinal ridging (n = 7), round white clods (n = 7), white dots (n = 7), and filiform hemorrhages (n = 7), followed by oval and linear white clods (n = 5), fuzzy lateral border (n = 5), and red-purple blood clods (n = 3). Nail clipping histopathology showed a thickened nail plate with multiple, small, round-to-oval spaces. The tumor expressed immunopositivity for LEF-1. Dermoscopy of the nail plate and nail clipping histology provides useful information with regards to the differential diagnosis with subungual squamous cell carcinoma and nail melanoma. Ex vivo-in vivo correlation facilitates a better dermoscopic assessment of this unique underrecognized disease. However, the differential diagnosis between OCM and onychocytic carcinoma requires biopsy of the tumor. LEF-1 as an onychogenic marker can be used to resolve the differential diagnosis between OCM and subungual longitudinal acanthoma/seborrheic keratosis.

Single-cell RNA sequencing unveils tumor heterogeneity and immune microenvironment between subungual and plantar melanoma

Acral melanoma (AM) is a subtype of melanoma with high prevalence in East Asians. AM is characterized by greater aggressiveness and lower survival rates. However, there are still fewer studies on immune mechanisms of AM especially subungual melanoma (SM) versus non-subungual melanoma (NSM). In order to explore tumor heterogeneity and immune microenvironment in different subtypes of AM, we applied single-cell RNA sequencing to 24,789 single cells isolated from the SM and plantar melanoma (PM) patients. Aspects of tumor heterogeneity, melanocytes from PM and SM had significant differences in gene expression, CNV and pathways in which tumor-associated such as NF-kb and Wnt were involved. Regarding the immune microenvironment, PM contained more fibroblasts and T/NK cells. The EPHA3-EFNA1 axis was expressed only in cancer-associated fibroblast (CAF) and melanocytes of PM, and the TIGIT-NECTIN2 axis was expressed in both AM subtypes of T/NK cells and melanocytes. Altogether, our study helps to elucidate the tumor heterogeneity in AM subpopulations and provides potential therapeutic targets for clinical research.

Outcomes Following Excision of Toe Glomus Tumors

BACKGROUND

Glomus tumors are uncommon tumors and their occurrence in the foot is even less common. Glomus tumors of the toes are often missed, causing delays in diagnosis and treatment. We report an ambispective observational study of glomus tumors of the toes that were treated at our institution.

METHODS

We reviewed the records of all the patients who underwent excision of toe glomus tumors in our department from January 2010 to September 2022. The follow-up data were collected from the outpatient records and by telephonic interview. Single Assessment Numeric Evaluation (SANE) score, Foot and Ankle Outcome Score (FAOS), and the Foot Function Index (FFI) were collected.

RESULTS

Out of all the patients treated for glomus tumors, we found that 7 patients had glomus tumors of the toes. Of the 7 patients, 6 were women and 1 was a male. The mean follow-up of our patients was 66.4 months (range, 7-109 months). Of the 7 patients, 1 presented with recurrent glomus tumor 30 months following the primary operation, for which she underwent excision again, after which she was symptom free. Another patient who developed recurrent symptoms on telephonic interview refused any further treatment. Among the 6 patients who were symptom-free at follow-up (including the patient who underwent excision for the recurrent tumor), the median SANE score, and FFI were 99.5 (IQR, 96-100) and 0.5 (IQR, 0-2) respectively. The mean FAOS was 96 (SD, 3.3).

CONCLUSION

Surgical excision of the subungual toe glomus tumors can be curative. Recurrence of toe glomus tumors was noted in 2 patients (29%), one of whom refused further surgery. Re-excision in the other patient resulted in complete resolution of symptoms.

LEVEL OF EVIDENCE

Level III, ambispective observational study.

Measuring Psoriasis Severity at Home

Psoriasis plaque severity metrics, such as induration (thickness), erythema (redness), and desquamation (scaliness), are associated with the subsequent development of psoriatic arthritis (PsA) among cutaneous-only psoriasis patients (patients with skin or nail psoriasis but no psoriatic arthritis). These metrics can be used for PsA screening. However, a key challenge in PsA screening is to optimize accessibility and minimize costs for patients, while also reducing the burden on healthcare systems. Therefore, an ideal screening tool consists of questions that patients can answer without a physician's assistance. Although reference images can be used to help a patient self-assess erythema and desquamation severity, a patient would need a tactile induration reference card to self-assess induration severity. This protocol describes how to create an induration reference card, the Psoriasis Thickness Reference Card, as well as how to use it to assess lesion induration severity. Administration of reference images for erythema and desquamation and a Psoriasis Thickness Reference Card for induration to 27 psoriasis patients showed that patients were moderately successful at self-assessing the severity of these three metrics. These findings support the feasibility of a future PsA screening test that patients can complete without the need for physician assistance.

Looking Beyond the Hutchinson Sign: A Retrospective Study of Clinical Factors Indicating the Presence and Invasiveness of Nail Unit Melanoma in Patients With Longitudinal Melanonychia

BACKGROUND

The data underlying this article are available in the article.Longitudinal melanonychia (LM) presents a challenge because nail unit melanoma (NUM) must be considered as a differential diagnosis. Because nail matrix biopsy may result in nail dystrophy, it is important to distinguish NUM from LM.

OBJECTIVE

To provide evidence of previously reported clinical factors indicative of NUM in patients with LM.

METHODS

This was a retrospective study of patients who presented with LM and had biopsy-confirmed NUM from 2005 to 2021. Benign LM was either confirmed by biopsy or considered benign if followed without the need for biopsy. Clinical factors associated with LM and NUM were compared by multivariate regression.

RESULTS

A total of 177 patients (97 LM and 80 NUM) were included. Multivariate regression showed that high band color intensity (p = .0031), variegation (p = .0005), nail plate splitting (p = .0017), Hutchinson sign (p = .0027), and band change (p = .001) correlated with malignancy. Nail plate splitting was associated with Breslow thickness.

CONCLUSION

Malignancy should be suspected and biopsy performed in patients with LM and high band color intensity, variegation, nail plate splitting, Hutchinson sign, and band change.

[Clinicopathological and prognostic features of subungual melanoma in situ]

Objective: To investigate the clinicopathological characteristics, immunohistochemical profiles, molecular features, and prognosis of subungual melanoma in situ (SMIS). Methods: Thirty cases of SMIS were collected in Fudan University Shanghai Cancer Center, Shanghai, China from 2018 to 2022. The clinicopathological characteristics and follow-up data were retrospectively analyzed. Histopathologic evaluation and immunohistochemical studies were carried out. By using Vysis melanoma fluorescence in situ hybridization (FISH) probe kit, combined with 9p21(CDKN2A) and 8q24(MYC) assays were performed. Results: There were 8 males and 22 females. The patients' ages ranged from 22 to 65 years (median 48 years). All patients presented with longitudinal melanonychia involving a single digit. Thumb was the most commonly affected digit (16/30, 53.3%). 56.7% (17/30) of the cases presented with Hutchinson's sign. Microscopically, melanocytes proliferated along the dermo-epithelial junction. Hyperchromatism and nuclear pleomorphism were two of the most common histological features. The melanocyte count ranged from 30 to 185. Most cases showed small to medium nuclear enlargement (29/30, 96.7%). Pagetoid spread was seen in all cases. Intra-epithelial mitoses were identified in 56.7% (17/30) of the cases. Involvement of nailfold was found in 19 cases, 4 of which were accompanied by cutaneous adnexal extension. The positive rates of SOX10, PNL2, Melan A, HMB45, S-100, and PRAME were 100.0%, 100.0%, 96.0%, 95.0%, 76.9%, and 83.3%, respectively. FISH analysis was positive in 6/9 of the cases. Follow-up data were available in 28 patients, and all of them were alive without disease. Conclusions: SMIS mainly shows small to medium-sized cells. High melanocyte count, hyperchromatism, nuclear pleomorphism, Pagetoid spreading, intra-epithelial mitosis, nailfold involvement, and cutaneous adnexal extension are important diagnostic hallmarks. Immunohistochemistry including SOX10 and PRAME, combined with FISH analysis, is valuable for the diagnosis of SMIS.

Glomus tumour: an institutional experience of 31 cases

BACKGROUND

Glomus tumour is an uncommon soft tissue tumour which commonly occurs in the distal extremities, particularly the subungual region of the finger. Due to its rarity, there is a paucity of literature concerning glomus tumour. Therefore, this paper aims to report a case series based on our institution's experience.

METHODS

A retrospective cross sectional study was performed in a single tertiary institution in Singapore. All patients diagnosed with glomus tumour confirmed on histology from January 2019 to October 2022 were included in the study. Patient demographics and clinical information (presenting signs and symptoms, tumour parameters and presence of recurrence) were retrieved from existing medical records.

RESULTS

A total of 31 cases of glomus tumour were diagnosed from January 2019 to October 2022, and the relevant demographics and clinical presentation were reported. Majority of glomus tumours occurred in the finger (61.3%). Pain was present in almost all the cases (96.8%), while a lump was visible in less than half (48.4%). An average of 44.0 months elapsed before patients were properly diagnosed and treated. There were no cases of recurrence despite involved margins in three cases.

CONCLUSION

Glomus tumour can be easily missed if clinicians do not have an index of suspicion for it, resulting in delayed treatment. Once diagnosed, glomus tumour can be treated with complete excision with good outcomes.

Foot Melanoma Localized to Subungual Toe Location Portends Poorer Prognosis

Our group previously reported that melanoma of the foot is associated with advanced disease on diagnosis and decreased survival. Lesions localized to the toe appeared to have the worst outcomes. In this study, we both expanded our study to include a 10-year population of patient with invasive melanoma of the foot and ankle and investigated additional factors associated with prognosis. Between January 2007 and December 2016, 211 patients underwent biopsy diagnosis and surgery for invasive melanoma in the BLANK health care system. Demographic, pathologic, staging, and localization characteristics were studied for overall survival. Lesions were localized to dorsal foot, plantar foot, toe (nonsubungual), and toe (subungual) locations. Multivariable analysis found Breslow depth, ulceration, lymph node involvement, and subungual toe location to be associated with poorer survival. Overall survival rate for foot melanoma was 70.6%. Overall survival for nonsubungual toe melanoma was 60.7%, compared to 53.1% for subungual toe melanoma. Of the subungual melanomas, 37.5% of presented as deep lesions with a Breslow depth >4.0 mm. Subungual melanoma was statistically significant for and found to be an independent prognostic factor associated with poorer survival and advanced disease. Based on the results of this study, there should be a low threshold to biopsy suspicious lesions of the toe and foot with particular attention to be dedicated to subungual lesions.

Clinical and dermoscopic features of nail unit melanoma in an Australian nail clinic cohort

Nail unit melanoma carries diagnostic challenges conferring with its poor prognosis. This audit aims to characterise both clinical and dermoscopic features of nail unit malignant lesions and compare them with biopsied benign lesions. It focuses on informing future practice by aiding in the stratification and recognition of malignant diagnostic patterns in the Australian context.

DeepNAPSI multi-reader nail psoriasis prediction using deep learning

Nail psoriasis occurs in about every second psoriasis patient. Both, finger and toe nails can be affected and also severely destroyed. Furthermore, nail psoriasis is associated with a more severe course of the disease and the development of psoriatic arthritis. User independent quantification of nail psoriasis, however, is challenging due to the heterogeneous involvement of matrix and nail bed. For this purpose, the nail psoriasis severity index (NAPSI) has been developed. Experts grade pathological changes of each nail of the patient leading to a maximum score of 80 for all nails of the hands. Application in clinical practice, however, is not feasible due to the time-intensive manual grading process especially if more nails are involved. In this work we aimed to automatically quantify the modified NAPSI (mNAPSI) of patients using neuronal networks retrospectively. First, we performed photographs of the hands of patients with psoriasis, psoriatic arthritis, and rheumatoid arthritis. In a second step, we collected and annotated the mNAPSI scores of 1154 nail photos. Followingly, we extracted each nail automatically using an automatic key-point-detection system. The agreement among the three readers with a Cronbach's alpha of 94% was very high. With the nail images individually available, we trained a transformer-based neural network (BEiT) to predict the mNAPSI score. The network reached a good performance with an area-under-receiver-operator-curve of 88% and an area-under precision-recall-curve (PR-AUC) of 63%. We could compare the results with the human annotations and achieved a very high positive Pearson correlation of 90% by aggregating the predictions of the network on the test set to the patient-level. Lastly, we provided open access to the whole system enabling the use of the mNAPSI in clinical practice.

Transverse erythronychia: A unique nail manifestation of COVID-19 infection and brief review of COVID-19 associated nail changes

Over the past 2 years, a plethora of mucocutaneous manifestations have been described to be associated with coronavirus 2019 (COVID-19) infection. Nail changes attributed to COVID-19 have rarely been documented in the literature. We describe here a unique nail finding 'transverse erythronychia' due to COVID-19 and review the literature on the diverse nail pathology attributed to the disease.

[Nail disorders in daily practice]

Familiarity with common nail disorders enables the clinician to diagnose and treat nail disorders and to recognize red-flag conditions. Knowledge of the anatomy of the nail unit is essential to understand the origin of nail disorders. This article focuses on neoplasms, abnormalities of nail color and shape, infections, and inflammatory conditions of the nail unit. There are various neoplasms of and around the nail unit, like squamous cell carcinoma (in situ), melanoma, and benign neoplasms such as mucous cyst, subungual exostosis, glomus tumor, onychopapilloma and fibro(kerato)ma. The most common deviating colors of the nail are red, white and brown-black. Abnormalities of nail color and shape may indicate an underlying systemic disease. Infections of the nail unit include onychomycosis, acute paronychia, pseudomonas nail infection and verruca vulgaris. The inflammatory conditions we discuss in this article are chronic paronychia, psoriasis, alopecia areata and lichen planus.

Dermatoscopic and clinical features of congenital or congenital-type nail matrix nevi: A multicenter prospective cohort study by the International Dermoscopy Society

BACKGROUND

Congenital nail matrix nevi (NMN) are difficult to diagnose because they feature clinical characteristics suggestive of adult subungual melanoma. Nail matrix biopsy is difficult to perform, especially in children.

OBJECTIVE

To describe the initial clinical and dermatoscopic features of NMN appearing at birth (congenital) or after birth but before the age of 5 years (congenital-type).

METHODS

We conducted a prospective, international, and consecutive data collection in 102 hospitals or private medical offices across 30 countries from 2009 to 2019.

RESULTS

There were 69 congenital and 161 congenital-type NMNs. Congenital and congenital-type NMN predominantly displayed an irregular pattern of longitudinal microlines (n = 146, 64%), reminiscent of subungual melanoma in adults. The distal fibrillar ("brush-like") pattern, present in 63 patients (27.8%), was more frequently encountered in congenital NMN than in congenital-type NMN (P = .012). Moreover, congenital NMN more frequently displayed a periungual pigmentation (P = .029) and Hutchinson's sign (P = .027) than did congenital-type NMN.

LIMITATIONS

Lack of systematic biopsy-proven diagnosis and heterogeneity of clinical and dermatoscopic photographs.

CONCLUSION

Congenital and congenital-type NMN showed worrisome clinical and dermatoscopic features similar to those observed in adulthood subungual melanoma. The distal fibrillar ("brush-like") pattern is a suggestive feature of congenital and congenital-type NMN.

PRAME expression in melanocytic lesions of the nail

BACKGROUND

Subungual melanoma can be diagnostically challenging. We evaluated the potential of PReferentially expressed Antigen for MElanoma (PRAME) immunoreactivity for differentiating benign from malignant nail melanocytic lesions.

METHODS

Sixty cases were identified (10 invasive melanomas, 8 melanomas in situ, 14 nevi, 12 cases of lentigo, and 16 of melanocytic activation). Percentage of PRAME-positive melanocytes was evaluated as follows: 0 no staining, 1+ 1%-25%, 2+ 26%-50%, 3+ 51%-75%, and 4+ >75%. A combined score of both percentage and intensity was also evaluated.

RESULTS

The difference in PRAME expression between malignant and benign lesions was statistically significant (p < 0.0001). The degree of PRAME expression significantly correlated with patients' age and clinical size. When based on percentage score, 61.1% of melanomas showed a 4+ score, 16.7% showed a 3+ score, 11.1% showed a 1+ score, and 11.1% was negative; 69.0% of the benign lesions was negative, 23.8% showed a 1+ score, 4.8% showed a 2+ score, and 2.4% showed a 4+ score. When the cutoff value for malignancy decreased from 4+ to 3+, the sensitivity increased from 61.1% to 77.8%, while specificity remained 97.6%. Combined score results were similar.

CONCLUSIONS

PRAME is a relatively sensitive and highly specific marker in differentiating benign from malignant nail melanocytic lesions. However, correlation with morphology is imperative.

Causes of longitudinal nail splitting: a retrospective 56-case series with clinical pathological correlation

BACKGROUND

Split nail (SN) is a rare type of nail fragility syndrome, characterized by a longitudinal fissure involving the entire thickness of the nail plate. Longitudinal nail splitting may be caused by direct injury to the nail plate or matrix insult. Few articles have been published on the topic, most were related to the traumatic aetiology. Some case reports mention tumours and inflammatory disorders as other causes.

OBJECTIVES AND METHODS

The aim of this retrospective study was to analyse the clinical and histopathological features of 56 SN collected at the nail consultation of the dermatology department at Saint Pierre University Hospital in Brussels, between 1997 and 2019.

RESULTS

Fifty-six patients were included (34 women and 22 men) with median age of 44.2 years. The fingernails were 3.2 times more frequently affected than toenails, especially the thumb. The most frequent aetiologies were tumours (45.6%), inflammatory diseases (26.3%) and traumas (19.3%). Congenital (5.3%) and systemic disorders (3.5%) were rarer causes. Histopathological slide review confirmed that alteration of the nail matrix integrity causes split nail, resulting either from matrix stretching by an underlying tumour or from impairment of the keratinization process by inflammatory diseases, melanocytic tumours and Bowen's disease.

CONCLUSIONS

This study is the largest case series of longitudinal nail splitting to date. It is the first to gather nail disorders causing SN with their clinical pathological correlation. The most common causes are traumatisms, tumours and inflammatory disorders. Congenital and systemic disorders are rarer. Tumours are responsible for half of the cases from which one third are malignant, mainly melanoma. When facing a monodactylic SN, benign as well as malignant tumours should be ruled out before concluding to traumatic aetiology.

Cyclin D1 and PRAME expression in distinguishing melanoma in situ from benign melanocytic proliferation of the nail unit

BACKGROUND

Distinguishing benign lesion from early malignancy in melanocytic lesions of the nail unit still remains a diagnostic challenge, both clinically and histopathologically. While several immunohistochemistry (IHC) stainings have been suggested to help discriminate benign subungual melanocytic proliferation (SMP) and subungual melanoma in situ (MIS), the diagnostic utility of IHC staining for cyclin D1 and PRAME has not been thoroughly investigated in melanocytic lesions of nail unit.

METHODS

This retrospective study included cases of benign SMP and subungual MIS confirmed by biopsy at Asan Medical Center from January 2016 to December 2020. Cases of melanocytic activation without proliferation and melanoma where dermal invasion was identified were excluded. Cyclin D1 and PRAME expression was assessed by counting proportion of melanocytes with nuclear positivity under 200x magnification.

RESULTS

A total of 14 patients with benign SMP and 13 patients with subungual MIS were included in this study. 11 patients with benign SMP (71.4%) and 5 patients with subungual MIS (38.5%) showed > 60% nuclear immunostaining for cyclin D1, respectively. While 13 patients with benign SMP (92.9%) showed totally negative staining for PRAME, 10 patients with subungual MIS (76.9%) exhibited > 50% nuclear immunostaining for PRAME. Using the cutoff of 10%, PRAME exhibited good overall discrimination between benign SMP and subungual MIS (AUC = 0.849, 95% CI = 0.659-0.957).

CONCLUSIONS

This study suggests that PRAME IHC staining as a reliable discriminator in distinguishing subungual MIS from benign SMP.

Clinical features and natural course of pediatric longitudinal melanonychia: A retrospective cohort study in Korea

BACKGROUND

Large studies on the clinical features and natural course of pediatric longitudinal melanonychia (LM) are lacking.

OBJECTIVE

To investigate the clinical features and natural course of pediatric LM METHODS: Retrospective cohort analysis of pediatric patients (age ≤18 years) with LM RESULTS: We examined 703 LM lesions in 381 children. Single, narrow, and homogeneously pigmented fingernail lesions were most frequently seen. Our results suggested that within 3, 4.5, and 9.5 years after onset, approximately 3%, 5%, and 10% of LM lesions, respectively, will completely regress and that single, left-sided, and homogeneously pigmented lesions are more likely to completely disappear. Age of onset, sex, finger/toe position, Hutchinson's sign, and nail dystrophy were not associated with complete regression. During follow up, most cases showed no change in color or width between the first and last visit, and early darkening/wider before stabilization or lightening/narrowing was common. Pigmentation becoming lighter was associated with complete regression; change in width was not.

LIMITATIONS

Retrospective study at a tertiary center CONCLUSION: Our results suggest that clinicians ought to follow up pediatric LM without intervention for several years, even if lesions grow darker or wider. Single, left-sided, and homogeneously colored lesions are more likely to regress.

[Glomus tumors of the fingers]

"Glomus tumors of the fingers. Glomus tumors of the fingers are benign lesions. The main symptom is a paroxysmal pain with particular hypersensiti¬vity to temperature changes. They are rare in their census, but there is very probably a very high rate of misdiagnosis, due to the very ignorance of their existence by the medical corpus. Their diagnosis is based on a typical clinical exami¬nation and characteristic imaging. The only treatment is their complete surgical resection, which is essential for recovery. Different surgical techniques have been described in the medical literature to achieve a painless finger without nail deformity after tumor resection, while limiting recurrences."

Nail matrix scars that result in nail dystrophy resemble cutaneous scars: A new nail trauma model

BACKGROUND

Few studies have described how the injury affects the nail soft tissue under the nail plate. Nail matrix scar is poorly known.

OBJECTIVE

To establish a stable rat nail loss model in a simple way, and to discuss the comparability of this model.

METHODS

A sterile cotton swab dipped in a 10% NaOH solution was used to burn the entire nail matrix and bed plane region, and the specimens were examined on day 3, 7, 14, and 28.

RESULTS

After avulsion of the nail plate, the eponychia and matrix stuck together without any tissue destruction. On day 28, all claws of the experimental group were observed to be permanently damaged, except for one claw malformed regeneration. All impaired nail regeneration had deficiency or functional loss of NMSCs and shared similar characteristics with the cutaneous scars.

CONCLUSIONS

The scar formation of nail matrix was a fundamental reason to nail deficiency of rat or human, providing a research basis for further mechanism or treatment study of nail defect diseases.

Functional Surgery for Subungual Melanoma: Surgical Tips Based on Histological Analysis of 21 Cadavers

BACKGROUND

Amputation has been the standard treatment for subungual melanoma. Although there is growing attention toward a more conservative functional surgery, specific operative techniques are not yet available.

OBJECTIVE

We aimed to provide objective measurements for use in functional surgery by analyzing the anatomy of the nail apparatus obtained from 21 cadavers.

MATERIALS AND METHODS

Nailbed thickness was histologically measured in each subunit, and skin surface anatomy was evaluated to determine the proximal resection margin. Immunohistochemical staining was performed to analyze microvessel distribution according to the nail subunit.

RESULTS

The nailbed thickness was the thinnest at the most proximal point of the nail matrix (thumbs, 1.10 ± 0.42 mm; big toes, 1.15 ± 0.37 mm) and the thickest at the hyponychium (thumbs, 2.86 ± 0.82 mm; big toes, 2.72 ± 0.84 mm). The distance from the eponychium to the skin surface closest to the bony cortex of extensor tendon insertion was 6.92 ± 5.13 mm in thumbs and 5.14 ± 1.59 mm in big toes. The median microvessel density was the highest at the hyponychium (25.74 vessels/mm2) and lowest at the germinal matrix (16.26 vessels/mm2) (p < .05).

CONCLUSION

This histological study offers practical tips, including those to help decide the proximal and deep resection margins, in functional surgery.

Hutchinson Sign: Biopsy May Assist in Diagnosis of Subungual Melanoma in Situ

BACKGROUND

Early and accurate diagnosis of subungual melanoma (SUM) through histopathologic examination is critical, but lack of clinical suspicion leads to delays in diagnosis. Hutchinson sign (HS) can be one of the important clinical indicators for diagnosing SUM.

OBJECTIVE

To evaluate the diagnostic value of small biopsies of HS for detecting SUM in situ.

METHODS

We retrospectively evaluated 12 patients who were diagnosed as SUM in situ and underwent punch biopsy at HS areas. Clinical features, dermoscopic findings, and histopathologic findings in HS regions were analyzed.

RESULTS

In most cases, HS was seen in hyponychium (11/12, 91.7%) with 1 case found in proximal nail fold, and 1 case in both the hyponychium and proximal nail fold. Dermoscopic features of HS showed irregular diffuse pigmentation (12/12, 100%) and parallel ridge pattern (7/12, 58.3%). Histopathologically, all cases showed irregularly scattered atypical melanocytes with hyperchromatic nuclei. Two cases showed subtle changes in melanocytes with little nuclear atypia, but additional section specimen showed more definitive findings of SUM in situ.

CONCLUSION

We present a supplementary biopsy technique for diagnosing SUM. Biopsy of HS may help in the diagnosis of SUM.

Subungual Melanoma: A Single Institution Experience

Despite the changing paradigms of melanoma treatment in recent years, there remains a relative paucity of data regarding subungual melanoma in the literature. From 2002–2018, 25 patients with subungual melanoma were surgically treated at our facility. A retrospective chart review was conducted to collect relevant demographic, clinical, pathologic, and outcomes data. The median age at diagnosis was 69 years. Most patients (60%) were male, and the melanoma lesion was most often located on the foot (68%). Acral-lentiginous was the most common histologic subtype (59%), and the median Breslow thickness was 3.4 mm. Fifteen patients (63%) underwent a sentinel lymph node biopsy as part of their surgical resection, and four of these patients (27%) had metastatic disease in the lymph nodes. In total, 10 patients underwent lymph node dissection of the involved basin. The median follow up was 21 months in this patient population. Age, gender, tumor location, ulceration, and lesion histology were not significantly associated with recurrence free survival (RFS). Increasing Breslow thickness was found to be significantly associated with shorter RFS (HR: 1.07, CI: 1.03–1.55). In total, 13 patients developed a disease recurrence, and RFS rates were 66% at 1 year and 40% at 3 years. Additionally, 91 and 37% of patients were alive at one year and three years, respectively. Subungual melanomas are rare lesions that often have a more advanced stage at diagnosis, which contributes to the poor prognosis of these cutaneous malignancies.

Tumor invasion in the hyponychium is associated with distant metastasis and poor prognosis in subungual melanoma: A histologic landscape of 44 cases

BACKGROUND

Subungual melanoma (SUM) has a poor prognosis because of delayed diagnosis. Its progression, consensus on surgical treatment, and correlation with clinical outcomes remain unclear.

OBJECTIVE

We aimed to identify the pattern of dermal invasion in different locations of the nail apparatus and its relationship with prognosis.

METHODS

In this retrospective review of surgically treated SUM patients between January 2011 and April 2019, the nail apparatus was divided into 5 anatomic subunits: the dorsal roof of proximal nail fold, ventral floor of proximal nail fold, germinal matrix, nail bed, and hyponychium. Invasions in the subunits were categorized using 3 criteria: no tumor, in situ tumor, or invasion.

RESULTS

Among 44 cases of SUM, dermal invasion occurred mostly in the distal areas, with 11, 30, 18, 7, and 4 in the hyponychium, nail bed, germinal matrix, ventral floor of proximal nail fold, and dorsal roof of proximal nail fold, respectively. The patients with hyponychial invasion showed a significantly greater Breslow depth (P = .009), a higher rate of lymph node metastasis (P = .019), distant metastasis (P = .036), and shorter disease-free survival (P = .001).

CONCLUSION

Hyponychial invasion is an important prognostic predictor of SUM, given its strong association with invasion depth, metastatic progression, and disease-free survival. Patients with invasion in the hyponychium should undergo more strict workup, treatment, and surveillance.

Nail Psoriasis Does Not Affect Skin Response to Ixekizumab in Patients With Moderate-To-Severe Psoriasis

Background: Presence of nail psoriasis in patients with plaque psoriasis may be an indicator of greater disease severity. Previously, patients with nail psoriasis have had delayed skin clearance after treatment compared to patients without nail psoriasis. Objective: This post-hoc analysis evaluated the efficacy of ixekizumab in clearance of plaque psoriasis in patients with and without nail psoriasis. Methods: Data were integrated from two phase 3 clinical trials (UNCOVER-2 and UNCOVER-3; N=2570) to assess skin response over 12 weeks of treatment with subcutaneous placebo, etanercept, or ixekizumab in patients with and without nail psoriasis. Nail response was assessed using Nail Psoriasis Severity Index (NAPSI) and skin response was assessed as the percentage of patients achieving 75%, 90%, or 100% improvement in Psoriasis Area and Severity Index (PASI 75, PASI 90, PASI 100) or a score of 0 or 1 on the static Physician Global Assessment (sPGA 0 or 0,1). Results: From baseline to week 12, progressive improvement in psoriasis occurred with ixekizumab and etanercept treatment; however, significantly more patients with nail psoriasis than without mild PASI 75 at weeks 8 and 12 and sPGA (0,1) at week 12 with ixekizumab. Significantly more patients with severe nail psoriasis than mild achieved PASI 75 at weeks 8 and 12 with ixekizumab. Conclusion: Patients with and without nail psoriasis responded well to ixekizumab. The presence of nail psoriasis did not negatively affect skin clearance in patients treated with ixekizumab. ClinicalTrials.gov: NCT01597245, NCT01646177 J Drugs Dermatol. 2020;19(8):741-746. doi:10.36849/JDD.2020.5116.

Unexpected subungual Sarcoptes infestation of toenail - a case report and literature review

Scabies is the skin infestation caused by Sarcoptes scabiei var hominis. It is one of the commonest dermatological infection which can affect people around the world. However, nails are relatively rarely involved, and the fingernails are mostly infected. The report a case of a 77-year-old woman, long-term pensioner of a nursing home, who had isolated toe subungual Sarcoptes infestation. In addition, the results of systematic review of toenails scabies was presented. Analysis of 21 subungual Sarcoptes infestation cases, revealed that patients in any age (median age 45+/-31.7-year-old) and sex can be affected. Most of the patients had concomitant diseases. Seventy-five percent of cases of nail involvement were treated with combined or sequential therapy. The most used drugs were ivermectin (IVR) and permethrin (PER) (each used in 47.6% cases), following γ-BHC (38.1%) and crotamiton (CRO) (23.8%). It seems that the crucial for adequate diagnosis in scabies affected nails is a precise anamnesis, early and accurate diagnosis that consists of examining not only skin lesions, but including assessing toenails, and differentiation of Sarcoptes infestation from other nail diseases as onychomycosis or psoriasis. Important to achieving a cure is at least frequent nail trimming, softening the nail plate with urea or in the difficult cases the mechanical removal of subungual plaque with using of a scabicide in the location allowing to penatrate it under the nail plate.

Non-Classic Signs of Sézary Syndrome: A Review

The majority of patients with Sézary syndrome (SS) present with classic symptoms of erythroderma, lymphadenopathy, and pruritus. However, there have been numerous reports of patients with SS who have non-classic signs. In this review, we report the less common clinical presentations of SS and discuss their relevant treatments. Our search included all literature on SS since 2008, the year the World Health Organization (WHO) incorporated the diagnostic criteria for SS into the WHO Classification of Tumours of Haematopoietic and Lymphoid Tissues. We reviewed 896 articles and identified 505 patients with non-classic presentations of SS. Of these 505 patients, the most common non-classic signs of SS were keratoderma, onychodystrophy, alopecia, leonine facies, and ectropion. Given the aggressive and highly symptomatic nature of SS, it is imperative that clinicians recognize the less common signs of the disease to prevent delays in diagnosis and treatment. To our knowledge, this is the first review of the clinical variations of SS with a focus on non-classic signs and symptoms.

Acremonium nail bed mycetoma masquerading as subungual squamous cell carcinoma

Acremonium is a large fungal genus that is comprised of approximately 150 species, found ubiquitously in nature. Although the majority are recognized as being saprophytes in soil and pathogens of plants, several species are emerging as causative agents of a variety of human infections, including mycetomas. Herein, we present a young man that was referred to our department with a painful subungual mass that developed following traumatic inoculation of Acremonium spp. In recent years, the role of Acremonium spp. has been increasingly recognized in localized infections, such as mycetoma, in humans. Other locally invasive as well as disseminated infections are also described. Optimal treatment of Acremonium spp. mycetoma is not well defined owing to the rarity of cases, thus posing a therapeutic challenge.

Intralesional Vitamin D3 in Recalcitrant Palmoplantar and Periungual Warts: A Prospective, Observational Study

Cutaneous warts are particularly difficult to treat with conventional treatment on sites such as the palms, soles, and periungual region. Immunotherapy boosts the host immune response and helps clear warts with less chance of recurrence. Vitamin D plays an important role in proliferation and differentiation of keratinocytes. The aim of this observational study was to study the efficacy and safety of intralesional vitamin D immunotherapy in the treatment of recalcitrant palmoplantar and periungual warts. Patients who had palmoplantar and periungual warts for more than 6 months and were non-responsive to at least two conventional treatment modalities were selected for the study. A maximum of four warts were injected with 0.2 mL of lignocaine (20 mg/mL), followed by intralesional injection of 0.2-0.5 mL of vitamin D3 (15 mg/mL), every 2 weeks for a maximum of four sessions. Response was assessed based on the reduction in the number of warts. A total of 63 patients were included in the study. The mean number of intralesional vitamin D3 injections required for complete clearance was 3.05±0.83 (mean ± Standard Deviation). Complete response was observed in 56 (88.9%) patients. Maximum clearance was observed in periungual warts (92.9%), followed by palmar warts (90.0%) and plantar warts (86.2%). The most common adverse effect was pain during injection (100.0%) and local swelling (25.4%). Two patients developed recurrence during follow-up. Immunotherapy with vitamin D3 appears to be an effective, inexpensive, and safe treatment in recalcitrant palmoplantar and periungual warts.

Melanonychia Striata: Nail Alterations during Pregnancy

A 35-year-old Greek woman (Fitzpatrick Skin Type IV) presented to our clinic 4 months after the delivery of her first child with nail changes that were first noted during pregnancy. During the 12th week of pregnancy, homogenous dark brown streaks appeared first on the nails of her right second and third fingers (Figure 1a, b) and later on her right fourth toenail (Figure 2a). During the following weeks, she developed similar changes on the second and fourth toenails (Figure 2b). The streaks were uniformly brown, with distinct margins and width of 2-5 mm. There was no pigmentation in the periungual skin (Hutchinson sign) of the affected nails. The direct microscopic examination, cultures, and polymerase chain reaction (PCR) were negative for dermatophytes. The nail changes had not resolved after delivery. Throughout the gestational period, she had developed alveolar hyperpigmentation, but no other changes including the lack of multiple lentigines. During her pregnancy, she had taken calcium supplements from the 8th week until delivery, magnesium and iron supplements throughout pregnancy, as well as progesterone 100 mg daily (Utrogestan®, Besins Healthcare Ltd) from the 8th week through the 12th week. She was otherwise healthy and had no previous pigmentation disorders, chronic diseases, or any other pregnancy complications. There was no family history of pigmentation disorders.

The causes of nail apparatus pigmentation presenting to a melanoma screening clinic a prospective study

BACKGROUND

Advanced stage primary cutaneous malignant melanoma (PCMM) has a high mortality. PCMM may affect any area of the skin, including the nail apparatus (malignant melanoma or subungual melanoma). Although nail apparatus malignant melanoma (NAMM) is rare, delayed diagnosis carries a poor prognosis.

AIM

The primary aim was to study the range of nail presentations and identify key patterns to aid in differential diagnosis. A secondary aim was to quantify the number of patients requiring surgery, indications for biopsy, and the incidence and characteristics of NAMM.

METHODS

This was a prospective study of all referrals with nail apparatus pigmentation to a weekly dedicated melanoma screening clinic over a 6-month period.

RESULTS

In total, 2246 patients were included. Of the 38 patients referred with nail pigmentation, 1 (2.6%) was diagnosed with NAMM and involved a fungating amelanotic lesion of the right hallux. The remaining patients were diagnosed with subungual haematoma (20/38; 52.6%), viral wart (2/38; 5.4%), acral fibrokeratoma (1/38; 2.6%), myxoid cyst (3/38; 7.9%), fungal nail infection (4/38; 10.5%), Pseudomonas nail infection (1/38; 2.6%), benign linear pigmentation (2/38, 5.3%), Bowen disease (1/38, 2.6%), psoriatic nail changes (2/38; 5.3%) and matrix malalignment (1/38; 2.6%). Of the eight patients (21.1%) who required surgery, five had a biopsy taken and three underwent surgery. Only 14 cases were followed up by Dermatology. NAMM accounted for 0.7% of all melanomas diagnosed.

CONCLUSION

We illustrate the wide range of diagnoses for pigmented nail presentations and highlight the late presentation of advanced disease in a patient presenting with NAMM.

Nail clipping in onychomycosis and comparison with normal nails and ungual psoriasis

BACKGROUND

Of all nail disorders seen in dermatology offices, half of them are due to onychomycosis. The main differential diagnosis is nail psoriasis. The objective of this study was to compare the microscopic findings, other than the presence of fungi, in the clipping of onychomycosis versus normal nails and nail psoriasis.

METHODS

Cross-sectional study of onychomycosis cases, analyzed by clipping and compared with data on normal nails and those with nail psoriasis.

RESULTS

Sixty-two onychomycosis samples were compared with 30 normal nails and 50 nails with psoriasis. In onychomycosis, measurement of subungual region, serous lakes, neutrophils and number of layers of parakeratosis are more intense than in psoriasis. Onychocariosis is less common in psoriasis, while bacteria are more frequent. The nail transition zone is more commonly blurred and irregular in onychomycosis.

CONCLUSION

Clipping helps in the differential diagnosis of onychomycosis and nail psoriasis and may be useful even when fungi are not found.

Analysis of nail-related content in the basic dermatology curriculum

Nail conditions are routinely encountered in dermatology clinical practice. Nails have important aesthetic functions, and onychodystrophies may cause pain and difficulties with ambulation and performing activities of daily living. Ideally, accurate diagnosis and optimal treatment of nail disorders are taught as early as medical school and extend into dermatology residency. We sought to determine the integration and content of nail education in the American Academy of Dermatology (AAD) Basic Dermatology Curriculum. Our results showed a paucity of nail content in this medical curriculum with only 101 total mentions of nails in 12 modules. Nail examinations were not mentioned as part of the full-body skin examination, nail unit melanoma was inadequately covered, and nail biopsy techniques were completely omitted. There is a notable need to enrich this curriculum with relevant nail content to educate students about the importance of nail disease.