Pigmented Nail Research Articles

A call for nail clipping histopathology to become an essential component of the routine evaluation of melanonychia: Benefitting patients as a triage and surgical planning maneuver.

We call on dermatologists and dermatopathologists to include nail clipping histopathology as an essential component of the routine evaluation of melanonychia. This manuscript demonstrates a case where an adult woman with broad melanonychia of the right thumbnail declined a nail matrix biopsy, but was amenable to a nail clipping.The nail clipping showed pigmentation, melanocyte remnants, and small cavities in the nail plate. These features have been published previously by our group as a clue to nail unit melanoma within nail clippings.This patient was rapidly triaged for nail matrix biopsy, which demonstrated nail unit melanoma in situ. Every patient with melanonychia can benefit from a nail clipping by examination of the location of the pigmentation within the nail plate for surgical planning, and if melanocyte remnants are detected, the nail clipping also serves as a rapid triage mechanism for nail matrix biopsy to evaluate for nail unit melanoma. Fontana-stained sections will highlight the pigmentation in the nail plate, and its location in the nail plate can easily be described by the dermatopathologist. Nail clippings performed in the setting of clinically apparent melanonychia may show helpful histopathologic findings of pigmented fungi, hemorrhage, external pigmentation, features of other pigmented nail unit tumors, as well as other entities. Nail clipping histopathology can provide extensive information in the evaluation of melanonychia with minimal discomfort for a patient, and little disruption to a physician's clinic flow. With this additional case of a nail unit melanoma diagnosed after initial concern found in a nail clipping, as well as other information in the literature, it is clear that melanocyte remnants found in nail clippings are reliable concerning features related to nail unit melanoma in adults. With knowledge of these histopathologic features in nail clippings and the significance of melanocyte remnants, the dermatopathologist can play a crucial role in the use of a nail clipping as a life-saving diagnostic maneuver. Accordingly, given the potential benefit to patients in this setting, as well as other uses of a nail clipping in the evaluation of melanonychia, we call on dermatologists and dermatopathologists to innovate the routine evaluation of melanonychia through the routine employment of nail clippings for histopathologic evaluation.

BH03: Assessing triage and screening of pigmented nail lesions via referral form

BH03: Assessing triage and screening of pigmented nail lesions via referral form

Diagnosis and treatment of nail melanoma: a review of the clinicopathologic, dermoscopic, and genetic characteristics.

Nail melanoma (NM) is an important differential diagnosis in patients with longitudinal melanonychia. However, diagnosis is often challenging as it is difficult to differentiate from other pigmented nail disorders. The main challenge for diagnosis is obtaining adequate nail matrix biopsy specimens for histopathological assessment. Furthermore, the histopathological changes in the early stages of NM are subtle and contribute to a delay in diagnosis and care. Therefore, the integration of clinical and histopathological analyses is essential. Clinical and dermoscopic features, such as a broadened width of asymmetric bands in an irregular pattern, with multicolour pigmentation, periungual pigmentation, and continuous growth, are features that support the diagnosis of NM. The essential histological features that must be assessed are cellular morphology, architectural features, melanocyte density, and inflammatory changes. The reported mutations in NMs were BRAF (0-43%), NRAS (0-31%), KIT (0-50%), NF1 (0-50%), and GNAQ (0-25%). Surgery is the primary treatment for NM. The recommended treatment for insitu or minimally invasive NM is functional surgery, but cases with suspected bone invasion should be treated with amputation. Targeted therapy and immunotherapy are indicated for advanced stages of NM. This review summarizes the updated guidelines for the diagnosis and treatment of NM.

The dermoscopic manifestation of nail pigmentation

Background and objectives: Nail pigmentations are of diagnostic challenging for dermatologists, as they may be involved in many local and systemic diseases that difficult to diagnose clinically. Our aim is to assess the specific dermoscopic features of different pigmented nail lesions. Methods: In our cross-sectional descriptive study; the total number of 46 patients with different types of nail pigmentation from all age groups and both sexes were included. Results: A total number of 46 patients, fungal melanonychia (n=14) was the commonest nail pigmentation found. In which the most common dermoscopic features were wide yellow streaks (100%). In drug-induced pigmentation (n=9) fine regular grey lines on a homogenous grey background were found. In Subungual hemorrhage (n=7) blood spots was the most common feature (100%). Lentigo (n=4) were associated with thin regular longitudinal grey lines on homogenous brown background. Nail melanocytic nevus (n=3) multiple, regular brown lines on the homogenous brown background was commonly found. In pseudomonal infection (n=5) bright green color mixed with dark green the most obvious feature. In nail-biting and in Laugier-Hunziker syndrome greyish coloration of background with thin longitudinal grey lines was the common feature. In melanoma (n=1) the dermoscopy showed the brown coloration of the nail plate background with irregular brown-black lines. Conclusions: Onychoscopy is a non-invasive device that collects much information that helping in the diagnosis of nail pigmentation.

Oral and nail pigmentations: a useful parallelism for the clinician.

Oral (OP) and nail (NP) pigmentations may occur simultaneously in physiological or pathological conditions, and may be a sign of underlying syndromic conditions that necessitate further investigation and treatment. Interestingly, the nail unit and oral cavity show a clinical parallelism that may help the clinician to conduct a correct examination and reach a prompt diagnosis. Both OP and NP can manifest clinically with focal or diffuse involvement and are due to external factors (exogenous pigmentation, drug-induced pigmentation) or endogenous factors (racial pigmentation, post-inflammatory pigmentation, nevi, genetic conditions and other disorders). The most concerning differential diagnosis is melanoma. Here we report the pathogenetic basis of OP and NP, together with the description of similar clinical features. To the best of our knowledge this is the first paper to summarize and describe the causes of pigmentation of both the oral cavity and the nail unit.

Dermoscopy and Reflectance Confocal Microscopy in the Diagnosis and Management of Nail Fold Squamous Cell Carcinoma

The management and prognosis of squamous cell carcinoma largely depend on its invasiveness and grade of differentiation. Pigmented nail fold squamous cell carcinoma represents a therapeutic challenge, needing careful treatment to preserve nail function. Here, we report the use of dermoscopy and Reflectance Confocal Microscopy to monitor nail fold squamous cell carcinoma in situ and its response to treatment with topical imiquimod.

Clinical and Dermoscopic Features of Fungal Melanonychia: Differentiating from Subungual Melanoma.

BackgroundFungal melanonychia (FM) is a rare nail disorder that presents as dark pigmentation in the nail plate because of fungal nail infection. The diagnosis of FM is occasionally confusing because its appearance is similar to melanonychia due to other causes including malignant melanoma. Dermoscopy could help increase the accuracy of diagnosing the cause of pigmented nail lesions. However, dermoscopic features of FM are not well elucidated.ObjectiveThis study aimed to investigate clinical and dermoscopic characteristics of FM.MethodsThe clinical features and dermoscopic findings of 20 patients diagnosed with FM and 14 patients diagnosed with subungual melanoma the Department of Dermatology of Pusan National University Hospitals (Busan and Yangsan) were retrospectively reviewed.ResultsFM mainly occurred as a solitary form in the toenail. Patients in the FM group were older than those in the subungual melanoma group. The most distinguishable general dermoscopic features in FM were a distal diffuse pattern, distal linear pattern, and light brown to yellowish color. FM-associated specific dermoscopic patterns such as the reverse triangular pattern, subungual hyperkeratosis, scale on the nail surface, and white or yellowish streaks were dominantly observed in the FM group compared to the subungual melanoma group.ConclusionFM-associated dermoscopic patterns and distal diffuse and linear patterns could be helpful diagnostic clues for differential diagnosis of FM from subungual melanoma.

JAAD Game Changers: Tangential excision of pigmented nail matrix lesions responsible for longitudinal melanonychia: Evaluation of the technique on a series of 30 patients

Capsule Summary•To our knowledge, no study concerning indications and outcomes of tangential matrix excision for longitudinal melanonychia has been carried out.•Pathological diagnosis on the entire lesion can be made. There is a discrete postoperative dystrophy rate. The drawback is postoperative recurrent pigmentation.•It should be limited to the removal of wide longitudinal melanonychia.How did this article change the practice of dermatology?The poor prognosis of nail melanoma is partially related to the delay in diagnosis. Reasons responsible for delay in diagnosis include lack of training in nail procedures among practitioners, fear of postbiopsy sequelae, and unfamiliarity with achieving effective anesthesia. In this retrospective study, the authors demonstrate that shave biopsy is an effective technique for diagnosing nail matrix lesions that cause longitudinal melanonychia over 4 mm wide while limiting the risk of postoperative sequelae. Moreover, it is relatively and easy procedure to perform.1

Immunohistochemical characterization of benign activation of junctional melanocytes and melanoma in situ of the nail unit.

Immunohistochemical (IHC) stains that distinguish benign, pigmented nail lesions from malignancy are needed. Candidate markers of malignant transformation include p16, HMB45, and Ki-67, with p16 being of particular interest. There is limited knowledge about the spectrum of p16 expression in pigmented lesions, especially junctional melanocytic proliferations of the nail. The objective of this study was to determine if any of these markers demonstrate diagnostic utility in distinguishing between benign activation of junctional melanocytes (BAM) and melanoma in situ (MIS) of the nail unit. In this retrospective study, ten cases of BAM and eight cases of MIS were identified. Archival slides available for review included H&E (hematoxylin and eosin), Fontana-Masson, and MelanA (Mart1) IHC slides. IHC studies for p16, HMB45, and dual-color Ki-67/MelanA (Mart1) were then performed. None of the tested IHC stains distinguished BAM from MIS. p16 IHC expression was uniformly negative with the exception of two cases of MIS. HMB45 was positive in all BAM and MIS cases. Ki-67/MelanA showed positive Ki-67 staining of MelanA-positive melanocytes in two cases of MIS, and all other cases of MIS and BAM were negative for Ki-67. The two positive p16 and two positive Ki-67/MelanA cases were non-overlapping. p16, HMB45, and Ki-67/MelanA IHC studies show no apparent utility in distinguishing BAM from MIS in the nail unit.

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

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

Use of Nail Dermoscopy in the Management of Melanonychia: Review.

The term melanonychia describes a black-brown-gray pigmentation of the nail plate that, in most cases, appears as a longitudinal band. Melanonychia can be observed at any age, affecting one digit or several digits, in both fingernails and toenails. Its causes can be difficult to differentiate clinically and depend on the number of bands and on their color, edge, and width. For this reason, especially in adults and when the pigmentation is localized in one single digit, biopsy and histopathological examination still represent the gold standard for a definitive diagnosis. Dermoscopy should be used routinely in the evaluation of a pigmented nail, as it provides important information for the management of melanonychia and can help avoid unnecessary nail biopsies. In cases of melanonychia it is important to establish whether the pigment is melanin or not and to determine whether the pigmentation of melanin is due to activation or proliferation and whether it is benign or malignant.

Dermoscopic features of conjunctival, mucosal, and nail pigmentations in a case of Laugier-Hunziker syndrome.

A 23-year-old man presented with multiple lip pigmentations. Longitudinal hyperpigmented streaks on his nails, as well as an ill-defined 2×3 mm pigmented spot on his right eye were noted (Figure 1). The family history was unremarkable. He was not taking any medication. Figure 1. Clinical view of labial (A), ungual (B) and conjunctival (H) pigmentations are shown. Dermoscopic findings included reticular lines (B), globules (C), and parallel lines (D) in the labial pigmentation; brown to gray longitudinal regular lines (F, G) in ... Colonoscopy and barium radiography of intestine were unremarkable. Complete blood count, complete metabolic panel, and urinalysis were within normal limits. The patient was diagnosed with Laugier-Hunziker syndrome (LHS). Dermoscopic examination of the lip pigmentations disclosed parallel lines, reticular lines and globules. The only recognized color was brown, which had a grayish hue in some parts of the lesion. A light brown colored homogeneous pattern was observed in the conjunctival pigmentation. The pigmented nail streaks showed brown-to-gray longitudinal regular lines (Figure 1). Histopathological examination of the labial pigmentation revealed basal keratinocyte pigmentation. No increase in the melanocyte count was identified with S100 and HMB45 immunohistochemical staining. Iron accumulation was not seen with specific Perls’ stain. The histopathological findings were compatible with the diagnosis of melanotic macule. Impression cytology examination of the conjunctival pigmentation revealed melanocytes with only a mild atypia suggesting a benign nature. The patient was processed to follow-up. LHS is a rare, acquired disease characterized by hyperpigmented macules of the lips and oral mucosa along with longitudinal melanonychia. Pigmentations in other mucosal surfaces may also exist. Although this syndrome is being regarded as benign, invasive mucosal melanoma has been reported in a case of LHS [1]. Parallel ridge pattern and irregular diffuse pigmentation in acral lesions; irregular lines on a brown background and micro-Hutchinson’s sign in nail apparatus lesions [2]; and the combination of blue, gray, or white color with structureless zones in mucosal lesions are the dermoscopic findings suggestive of melanoma [3]. Little data exists regarding the dermoscopic features of conjunctival pigmentations in the literature. Atypical pigment network, irregular dots and globules, regression structures, and a blue-white veil are the dermoscopic findings reported in a case of palpebral conjunctival melanoma [4]. Dermoscopic findings may differ from usual in some pigmentation syndromes including LHS. Parallel ridge pattern has been determined in benign acral pigmentations of several LHS cases [5–7]. Although nail pigmentations in LHS have been found to demonstrate similar dermoscopic findings with that seen in ethnic type and drug induced pigmentation, which are regular linear pigmentation lines on a grayish background, micro-Hutchinson’s sign have also been reported in benign nail pigmentations of some LHS cases [2,5,8]. Parallel furrow pattern, brown and blue-gray granular pigmentation along with linear and dotted vessels on whitish pink areas are the dermoscopic findings reported in labial pigmentations of LHS cases [5]. The only LHS case with labial melanoma in the literature exhibited blue-whitish veil on dermoscopic examination [1]. Dermoscopic findings in the present case were consistent with benign nature. The dermoscopic finding of a conjunctival pigmentation in LHS is being reported for the first time by the present study. The identification of dermoscopic features of this syndrome may simplify the management of LHS. Further reports are necessary to arrive at a conclusion.

Melanonychia striata secondary to pigmented nail matrix fibroma simulating nodular melanoma

Melanonychia corresponds to color patterns in the nail plate, ranging from brown to black. It is a diagnostic challenge due to the fact it has several differential diagnoses, including benign and malignant entities. There are no reports of pigmented fibroma of the nail matrix causing striata (or longitudinal) melanonychia. In light of this fact, the authors report a case of melanonychia striata secondary to pigmented fibroma of the nail, with clinical examination and dermoscopic findings suggestive of nodular melanoma.

Longitudinal Melanonychia of the Toenail

A man in his 60s presented with a pigmented nail streak on the left fourth toenail that had been present for 10 months. He denied pain, tenderness, or trauma. Physical examination revealed a 4-mm wide pigmented streak with varying shades of brown and longitudinal ridging (Figure, A). The nail fold was uninvolved. Because of suspicion for melanoma, a biopsy was recommended. A nail avulsion was performed and demonstrated a 3-mm tan papule beneath the proximal nail fold (Figure, B). The histologic findings are shown in Figure, C. What is your diagnosis?

Dermatoskopie der Nägel

Pigmented and nonpigmented nail abnormalities often represent a challenge for clinicians because many, and sometimes potentially life-threatening differential diagnoses must be taken into consideration. Although many details of nail diseases can already be assessed with the naked eye, dermoscopy opens up a second microscopic level of inspection, which can be very useful for the diagnostic process. In the last 20 years dermoscopy has made rapid progress in the further development of criteria for the early recognition of melanoma. In addition, the use of dermoscopy has been extended to the examination of cutaneous adnexa, such as hairs (trichoscopy) and nails (onychoscopy). Many, sometimes highly specific criteria for the dermoscopic assessment of nail diseases have been described in a series of recently published articles. This review article provides important diagnostic aids for a well-founded dermoscopic assessment of nail diseases.

Pigmentations of the Nails

Nail pigmentations can exhibit many different colors and shades. Most of them are harmless but cosmetically embarrassing, others are potentially serious and may lead to death if not adequately diagnosed and treated. This short review gives an explanation for a number of nail dyschromias and their etiologies as well as some hints as to their treatment.

Tangential excision of pigmented nail matrix lesions responsible for longitudinal melanonychia: Evaluation of the technique on a series of 30 patients

We sought to assess the shave biopsy technique, which is a new surgical procedure for complete removal of longitudinal melanonychia. We evaluated the quality of the specimen submitted for pathological examination, assessed the postoperative outcome, and ascertained its indication between the other types of matrix biopsies. This was a retrospective study performed at the dermatologic departments of the Universities of Liège and Brussels, Belgium, of 30 patients with longitudinal or total melanonychia. Pathological diagnosis was made in all cases; 23 patients were followed up during a period of 6 to 40 months. Seventeen patients had no postoperative nail plate dystrophy (74%) but 16 patients had recurrence of pigmentation (70%). This was a retrospective study. Shave biopsy is an effective technique for dealing with nail matrix lesions that cause longitudinal melanonychia over 4 mm wide. Recurrence of pigmentation is the main drawback of the procedure.

Perioperative confocal microscopy of the nail matrix in the management ofin situor minimally invasive subungual melanomas

Although dermoscopy of the nail plate is helpful to discriminate between benign and malignant causes of nail pigmentations, there remain ambiguous cases in which a matricial biopsy is required. When a subungual melanoma is diagnosed histopathologically, a complementary surgical treatment is performed secondarily, the duration of postoperative disability being accordingly prolongated. The purpose of our study was to evaluate the feasibility of an intraoperative diagnosis by reflectance confocal microscopy (RCM). Our series included nine consecutive patients who underwent a matricial biopsy for an acquired melanonychia (one benign lentigo and eight melanomas). RCM examination was performed in vivo on the nail matrix after reclination of the nail plate, and/or ex vivo on the fresh tissue biopsy. RCM data were compared with histopathology. There was a good correlation between confocal and histopathological features. Seven melanoma cases were unequivocally diagnosed intraoperatively according to the confocal features, whereas the lentigo was correctly classified as a benign lesion according to RCM. The remaining lesion could not be unequivocally classified by RCM and corresponded histopathologically to an early melanoma that required immunostaining to be diagnosed. Intraoperative RCM examination of the nail matrix is an efficient diagnostic approach of melanonychia striata that permits an extemporaneous diagnosis of malignancy and therefore a one-step surgical treatment of in situ or minimally invasive melanoma, reducing dramatically the duration of postoperative disability.

Patterns of nail matrix and bed of longitudinal melanonychia by intraoperative dermatoscopy

The dermatoscopic examination of the nail plate has been recently introduced for the evaluation of pigmented nail lesions. There is, however, no evidence that this technique improves diagnostic accuracy of in situ melanoma. To establish and validate patterns for intraoperative dermatoscopy of the nail matrix. Intraoperative nail matrix dermatoscopy was performed in 100 consecutive bands of longitudinal melanonychia that were excised and submitted to histopathologic examination. We identified 4 dermatoscopic patterns: regular gray pattern (hypermelanosis), regular brown pattern (benign melanocytic hyperplasia), regular brown pattern with globules or blotch (melanocytic nevi), and irregular pattern (melanoma). Nail matrix dermatoscopy is an invasive procedure that can not routinely be performed in all cases of melanonychia. The patterns described present high sensitivity and specificity for intraoperative differential diagnosis of pigmented nail lesions.

Dermatoscopy - an Investigative Method and Valuable Tool

Introduction: dermatoscopy is a non-invasive technique which allows us to explore and evaluate the structures of the epidermis, the dermo-epidermal junction and the papillary dermal layer in vivo. Cognition of the specific diagnostic patterns lead to a right clue and proper diagnosis suggestion. Dermatoscopy depends on the timely correct recognizing of dermatoscopic findings and features and is therefore terminated and limited by time input and by experience of a physician. Dermatoscopy gained a great role in general dermatology with its importance in early diagnostics of a malignant melanoma and has become a valuable tool for the diagnosis of a various infectious and inflammatory diseases, nail pigmentations, hair abnormalities and scalp disorders including ectoparasitic infestations, cutaneous/ mucosal infections, psoriasis. Patients and methods: investigations are provided by dermatoscopy equipment – Dermatoscope MoleMax II. Our study included 791 patients (490 women and 301 men), in which we recorded a total of 1670 lesions in the period from May 9, to May 13, 2011. Results: from the total number of lesions analyzed there were 944 melanocytic and 726 nonmelanocytic lesions. Within melanocytic lesions, histopathology confirmed 9 malignant melanomas. From nonmelanocytic lesions present were: seborrheic keratosis 307, actinic keratoses (precancerosis) 118, hemangiomas 77 and bacocelular skin cancer BCC 68. Discussion: dermatoscopy is a method of epiluminiscent microscopy that in the analysis of tumor skin changes has completely replaced the standard magnifying glass. Credibility of dermatoscopy is going from 70-90% and the dermatoscopy became an indispensable diagnostic tool in the analysis of tumor changes on the skin. Conclusion: the dermatoscopy is valuable tool in diagnostics of variety of skin disorders in the field of general dermatology.