Retronychia: the importance of proper footwear.

Retronychia is commonly underdiagnosed and exhibits classic features of proximal nail fold elevation and nail plate layering. Herein we summarize the literature and discuss cause, diagnosis, and treatment of this condition.

Subungual Osteochondroma of the Great Toe: A Case Report.

Bony outgrowths of the distal phalanx of the great toe have been described in the literature but rarely. These subungual bony outgrowths can be caused by subungual exostosis or subungual osteochondromas. Both of these abnormalities are bony outgrowths with differences in the cartilage cap wherein the exostoses have fibrocartilage, and osteochondromas have hyaline cartilage. The subungual exostosis and osteochondroma that are protruding present symptoms of pain, redness, and deformed nail bed, whereas the nonprotruding osteochondromas have only a lump as the presenting symptom. In both conditions, excision of the lesion and curettage of the base helps prevent a recurrence. Curettage at the end of the excision of the bony outgrowth is required to avoid recurrence. After excision, the specimen should be sent for histopathologic examination to differentiate between the exostosis and osteochondromas, which are underreported in subungual locations, and to rule out malignant transformation. We present a 13-year-old girl with an isolated subungual nonprotruding exostosis of the great toe that was treated by excisional biopsy. The histopathologic examination confirmed it as osteochondroma, which is underreported.

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 â€‹= â€‹27) and AM (n â€‹= â€‹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 â€‹= â€‹0.612). Sentinel node positivity was associated with significantly worse overall survival outcome (Hazard Ratio 5.49; CI (1.59-18.97), p â€‹= â€‹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 â€‹= â€‹0.043). Proximal amputations were associated with significantly worse OS (p â€‹< â€‹0.002) and RFS (p â€‹< â€‹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.

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.

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.

Successful treatment of onychomatricoma with minimally invasive surgical procedures based on its pathogenesis: A case report.

Onychomatricoma is a rare, fibroepithelial tumor of the nail. Although it is benign, unnecessary and excessive treatment, such as extensive or total removal of the nail matrix, has been reported in the past. Recently, it was speculated that onychomatricoma is derived from onychomatricodermis, the dermal stroma of the nail matrix. Excision of the stromal rather than the epithelial component of the tumor is important. However, since the boundary between the normal and diseased stroma is usually unclear, minimal excision at the base of the tumor projection should be sufficient. We report a case of onychomatricoma and suggest a method of surgical treatment that would minimize postoperative deformity of the nail plate.

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.

SUBUNGUAL HEMATOMA OVERLAPPING WITH SUBUNGUAL LOCATED FOCAL MELANOCYTIC HYPERPLASIA: DERMATOSURGICAL APPROACH AS OPTIMAL TREATMENT CHOICE.

Subungual lesions present a serious challenge for clinicians. The following factors can cause certain problems in interpreting the data: 1) Changes in lesion morphology over time: It may indicate the presence of a malignant lesion (increased pigmentation over time and lack of distal growth) but may actually be a benign lesion (chronic persistent subungual hematoma). 2) Patient's medical history can be misleading or difficult to verify, especially in problematic patients, or those with mental health problems or communication disorders (e.g., Asperger's syndrome, autism, schizoid psychosis, etc.). 3) The morphology of the lesion itself can be difficult to determine in the presence of simultaneously overlapping lesions. These patient dilemmas primarily concern the differentiation between subungual hematomas from subungual melanomas. The clinicians's concerns are based on the potential for metastasis and the risk of significantly worse prognosis for patients affected by nail biopsy. We present a 19-year-old patient with a subungual pigmented lesion with a clinical/dermatoscopic suspicion for subungual melanoma. Primary complaints for about 3-4 months. Intensified pigmentation and increase in size within two months led to a partial surgical resection of the nail plate and nail bed, followed by adaptation of the wound edges with single interrupted sutures. The histopathological finding was indicative of a subungual hematoma located above a focal melanocytic hyperplasia of the nail bed, clear resection lines. After a literature review, we believe that this is the first case of a patient with simultaneously present subungual benign focal melanocytic hyperplasia overlapping with a chronic persistent subungual hematoma.

Chronic Polymicrobial Infectious Melanonychia Striata.

CASE: A 62-year-old man presented with a 10-year history of isolated melanonychia striata of his dominant thumb. Surgical biopsy ruled out subungual melanoma but revealed foreign plant material causing chronic infectious melanonychia from multiple pathogens, including Pseudomonas aeruginosa, Escherichia coli, and Candida spp. After removal of the nail plate and thorough debridement, the melanonychial streak resolved completely at 12 months of follow-up. CONCLUSION: Bacterial infection is a rarely reported cause of melanonychia, and in addition to surgical pathologic specimens, intraoperative fungal and bacterial cultures should always be obtained for accurate diagnosis of melanonychia striata.

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.