EFFECTIVE DETECTION OF PLANTAR MALIGNANT MELANOMA

Background: As the sole of the foot is the most prevalent site of malignant melanoma in non-Caucasians, early detection of the neoplasm at this anatomical site is very important. In our previous study, we proposed a clinical guideline that acquired melanocytic lesions on the sole larger than 7 mm in maximum diameter should be examined histologically. Methods: Eighty-one Japanese patients with the complaint of plantar pigmented lesions were screened at our dermatology clinic during 3 years using the 7-mm criterion. Results: Of the total 80 melanocytic lesions on the sole, 14 lesions were larger than 7 mm in maximum diameter, excluding congenital lesions. Diagnoses of the 14 “large” lesions were as follows: advanced malignant melanoma, 8 lesions; early malignant melanoma (malignant melanoma in situ), 1 lesion; acquired melanocytic nevus, 4 lesions, and volar melanotic macule, 1 lesion. Conclusions: The present study confirmed the validity of the 7-mm criterion for the early effective detection of plantar malignant melanoma.     

Automated evaluation system of dermoscopic images of longitudinal melanonychia: Proposition of a discrimination index for detecting early nail apparatus melanoma

The prognosis of nail apparatus melanoma is generally poor because of difficulty in early stage diagnosis. Most nail apparatus melanomas occur as longitudinal melanonychia, and criteria and algorithms for dermoscopy diagnosis of longitudinal melanonychia have only recently been proposed. However, as with any clinical diagnosis, the diagnosis based on dermoscopy is to some extent subjective. Our goal is to develop an automated dermoscopic screening system for longitudinal melanonychia and to propose a novel objective and quantitative index for discriminating early nail apparatus melanoma from benign longitudinal melanonychia including melanocytic nevus. We propose an automatically calculated index representing degrees of color variegation in dermoscopic images of longitudinal melanonychia. Dermoscopy images of six cases of early stage nail apparatus melanoma and 25 cases of benign longitudinal melanonychia were analyzed with our screening system and a threshold of melanoma discrimination index was determined. This single melanoma discrimination index diagnosed early nail apparatus melanoma with 100% sensitivity and 92% specificity. The automatically calculated index proposed in the present study is valuable for managing longitudinal melanonychia. The results suggest that the degree of color variegation is essentially different between early nail apparatus melanoma and benign longitudinal melanonychia including melanocytic nevus of the nail apparatus.     

Nail apparatus melanoma: a diagnostic opportunity

Malignant Melanoma is a high mortality neoplasm. The involvement of the nail apparatus is rare, with only 2 out of 3 patients seeking medical attention as the result of recent nail melanocytic lesions. This results in late diagnosis and a prognosis worse than cutaneous melanoma. We report a female, presenting with ulcerative lesions with clinical and laboratory features compatible with leishmaniasis. On return after treatment initiation a longitudinal melanonychia was observed on her first right finger. Biopsy of the nail matrix was performed. Histopathology was compatible with melanoma in situ. Longitudinal melanonychia is not a specific sign for melanoma and it is important that the dermatologist should identify the suspect lesions correctly. The incidental diagnosis of nail melanoma in situ in our case significantly impacted the patient''s survival.     

Nail tumors

Most neoplasms of the nail apparatus have different clinical appearances, courses, and biological behaviors as compared with similar tumors located elsewhere on the skin. Some of these tumors are unique to the nail, such as onychomatricoma. As a general rule, benign lesions respect the general architecture of the nail apparatus, whereas malignant ones are destructive. Our review covers the most common nail tumors, from benign ones to the most frequent nail malignancy, the squamous cell carcinoma, which actually is the greatest simulator. We will also discuss new approaches to the diagnosis and treatment of melanoma of the nail apparatus. Physicians should be aware of these conditions and their management.     

Pilot study on the correlation between dermoscopic patterns and fluorescence in situ hybridization findings using whole‐slide digital imaging for acral volar melanocytic lesions

Dermoscopic evaluation of acral volar skin is helpful in differentiating malignant melanomas (MM) from benign melanocytic nevi. However, histological diagnosis remains difficult because sufficient evidence of histopathological changes to establish a diagnosis of MM are not easily obtained. The aim of the present study was to evaluate the effective use of fluorescence in situ hybridization (FISH) in the diagnosis of acral volar melanocytic lesions, and to determine whether acral volar melanocytic lesions show characteristic molecular biological features of malignant melanoma via FISH. We classified acral volar melanocytic lesions showing junctional findings into three groups: (A) parallel ridge pattern (PRP) on dermoscopic examination with melanoma in situ; (B) PRP with insufficient melanocyte proliferation and atypia to diagnose malignant melanoma using hematoxylin–eosin staining; and (C) junctional nevi. We performed FISH analysis using the same tissue section that was used for hematoxylin–eosin staining. FISH positivity was seen in 80% (4/5) of the group A sections, and in 80% (4/5) of the group B sections. One case in group C was only 0.3% over the established criteria line (63.3% > 63% in RREB1). Our results suggest that FISH using whole‐slide digital imaging may be useful in the diagnosis of early in situ MM when a typical PRP is observed in an acral volar skin lesion with non‐diagnostic histopathology.     

Dermoscopic examination of nail pigmentation

BACKGROUND: Diagnosis of longitudinal melanonychia is usually difficult, and neither a single clinical criterion nor a combination of symptoms currently can be used to clearly distinguish malignant from benign bandlike pigmented nail lesions. Biopsy is painful and often leaves definitive dystrophic scars. OBJECTIVES: To describe and evaluate dermoscopic patterns associated with longitudinal nail pigmentation. PATIENTS AND METHODS: A total of 148 unselected consecutive cases of longitudinal melanonychia were included over a period of 4 years (20 melanoma, 37 nevi, 16 drug-induced nail pigmentation, 45 nail apparatus lentigo of various types, 8 ethnic-type nail pigmentation, and 22 subungual hemorrhages). All patients were recruited from the dermatology unit outpatient clinic of the H?tel Dieu de Lyon. All cases were photographed in vivo under oil immersion (dermoscopy). Patterns were recorded prior to final pathologic diagnosis. An independent biostatistics unit performed statistical evaluation using 7 semiologic patterns. RESULTS: Melanoma cases were significantly associated with a brown coloration of the background and the presence of irregular longitudinal lines (P =.001). Blood spots were mostly observed in subungual hemorrhages (P =.001); however, their presence could not rule out melanoma. Micro-Hutchinson sign was observed only in melanoma, but its rare occurrence did not allow any statistical evaluation of its specificity. Nail apparatus nevi were significantly associated with a brown coloration of the background and the presence of regular lines (P =.001). Nail apparatus lentigo, ethnic-type pigmentation, and drug-induced pigmentation were significantly associated with homogeneous longitudinal thin gray lines and gray coloration of the background (P =.001). Microscopic longitudinal grooves were unspecific, occurred in several conditions, and were associated with any type of ungual discoloration. CONCLUSIONS: We believe that dermoscopic examination of the nail plate in cases of longitudinal melanonychia provides useful information that could help clinicians to more accurately decide if a nail apparatus biopsy should be performed; however, histopathologic diagnosis remains the gold standard in doubtful cases.     

CONTINUING MEDICAL EDUCATION REVIEW Nail apparatus melanoma

Nail apparatus melanoma is a relatively rare variant of melanoma with a disproportionately high mortality when compared with melanoma elsewhere. The aetiology and natural history remain poorly understood. There is no clear epidemiological association with race, skin type or sun exposure. Universally accepted clinical and histological criteria for the diagnosis of early nail apparatus melanoma have not been defined. The two cardinal clinical signs are melanonychia striata and Hutchinson’s sign. These are useful but not pathognomonic of melanoma. Diagnostic delay is frequent and patients commonly have advanced disease at the time of diagnosis. Surgical excision is advocated for treatment of stage I disease; however, the most appropriate re‐excision margins, including the level of amputation where required, have not been determined. Early diagnosis and excision of the tumour is the only treatment known to increase survival. Adjuvant systemic chemotherapy, isolated limb perfusion, and routine elective lymph node dissection have been used, but no survival benefit has been demonstrated.     

Nail apparatus melanoma

Nail apparatus melanoma is a relatively rare variant of melanoma with a disproportionately high mortality when compared with melanoma elsewhere. The aetiology and natural history remain poorly understood. There is no clear epidemiological association with race, skin type or sun exposure. Universally accepted clinical and histological criteria for the diagnosis of early nail apparatus melanoma have not been defined. The two cardinal clinical signs are melanonychia striata and Hutchinson's sign. These are useful but not pathognomonic of melanoma. Diagnostic delay is frequent and patients commonly have advanced disease at the time of diagnosis. Surgical excision is advocated for treatment of stage I disease; however, the most appropriate re-excision margins, including the level of amputation where required, have not been determined. Early diagnosis and excision of the tumour is the only treatment known to increase survival. Adjuvant systemic chemotherapy, isolated limb perfusion, and routine elective lymph node dissection have been used, but no survival benefit has been demonstrated.     

Melanonychia striata: clarifying behind the Black Curtain. A review on clinical evaluation and management of the 21st century

Melanonychia striata is characterized by a tan, brown, or black longitudinal streak within the nail plate that runs from the proximal nail fold to the distal part of the nail plate. Melanonychia striata is due to increased activity of melanocytes or melanocytic hyperplasia in the nail matrix with subsequently increased melanin deposition in the nail plate. The most common cause of melanonychia striata associated with melanocytic activation is ethnic melanonychia which occurs in dark-skinned individuals. Other causes of melanonychia striata related to melanocytic activation include pregnancy, chronic local trauma, infections, medications, dermatological disorders, endocrine disorders, alkaptonuria, hemochromatosis, porphyria, graft-vs-host disease, Peutz-Jeghers syndrome, and Laugier-Hunziker syndrome. Causes of melanonychia striata associated with melanocytic hyperplasia include nail matrix melanocytic nevus, nail lentigo, and nail apparatus/subungual in situ and invasive melanoma. In most cases, melanonychia striata is a benign condition, especially in children. Consequently, most investigators advocate a wait-and-see approach. Nail apparatus/subungual melanoma should be suspected if there is an abrupt onset after middle age, personal or family history of melanoma, rapid growth, darkening of a melanonychia band, pigment variegation, blurry lateral borders, irregular elevation of the surface, a bandwidth >3 mm, proximal widening, associated nail plate dystrophy, single rather than multiple digit involvement, and periungual spread of pigmentation onto the adjacent cuticle and/or proximal and/or lateral nail folds (Hutchinson sign). Prolonged follow-up is mandatory for early detection of possible malignant changes.     

Conservative surgical management of subungual (matrix derived) melanoma: report of seven cases and literature review

Background Subungual melanoma (SUM) is a rare entity, comprising approximately 0·7–3·5% of all melanoma subtypes. SUM histopathologically belongs to the acral lentiginous pathological subtype of malignant melanoma. Its diagnosis is helped by dermoscopy but pathological examination of doubtful cases is required. Classical management of SUM is based on radical surgery, namely distal phalanx amputation. Conservative treatment with nonamputative wide excision of the nail unit followed by a skin graft has been insufficiently reported in the medical literature even though it is performed in many centres. Objectives To report a series of patients with in situ or minimally invasive SUM treated by conservative surgery, to investigate the postoperative evolution and to evaluate the outcome with a review of the literature. Methods We performed a retrospective extraction study from our melanoma register of all patients with in situ and minimally invasive SUM treated with conservative surgery in the University Hospital Department of Dermatology, Lyon, France from 2004 to 2009. The patient demographics, disease presentation, delay to diagnosis, histopathology and postoperative evolution were reviewed. Results Seven cases of SUM treated as such were identified in our melanoma database. All cases had a clinical presentation of melanonychia striata. The mean delay to diagnosis was 2 years. Surgical excision of the entire nail unit with a 5–10 mm safety margin without bone resection followed by full‐thickness skin graft taken from the arm was performed in all cases. No recurrence was observed with a mean follow‐up of 45 months. Functional results were found satisfactory by all patients and their referring physicians. Sixty‐two other cases have been found in the literature and are also discussed. Conclusions Conservative surgical management in patients with in situ or minimally invasive SUM is a procedure with good cosmetic and functional outcome and, in our cases as well as in the literature, the prognosis is not changed.     

早期甲黑素瘤115例手术治疗方案和预后回顾分析

【摘要】 目的 探讨早期甲黑素瘤的手术治疗方案和预后。方法 回顾并分析第四军医大学西京皮肤医院2011年7月至2019年12月收集的115例早期甲黑素瘤的手术治疗方案及预后。结果 115例早期甲黑素瘤患者按改良的ABCDEF标准并根据如甲板改变、溃疡、结节等临床表现评估后，73例按原位甲黑素瘤扩大切除，22例按Ⅰ、Ⅱ期甲黑素瘤扩大切除，20例按Ⅰ、Ⅱ期甲黑素瘤且有浸润风险方案扩大切除。随访6个月至9年，所有患者均未出现原发灶复发； 101例患者淋巴结B超检查未见异常；2例截指患者出现转移，其中1例死亡；失访12例。结论 依据患者甲黑素瘤临床表现选择手术扩大切除方案治疗早期甲黑素瘤，可以在确保充分治疗的基础上，最大程度保留肢端正常功能，且不会出现原发灶复发。     

Maligne Tumoren des Nagelorgans

Because of the large number of different tissues making up the distal phalanx of fingers and toes, a large variety of malignant tumors can be found in and around the nail apparatus. Bowen disease is probably the most frequent nail malignancy. It is usually seen as a verrucous plaque of the nail fold and nail bed in persons above the age of 40 years. It slowly grows over a period of years or even decades before degenerating to an invasive squamous cell carcinoma. The latter may also occur primarily often as a weeping onycholysis. The next most frequent nail malignancy is ungual melanoma. Those arising from the matrix are usually pigmented and often start with a longitudinal melanonychia whereas those originating from the nail bed remain amelanotic, are often nodular and mistaken for an ingrown nail in an elderly person. The treatment of choice for in situ and early invasive subungual melanomas is generous extirpation of the nail apparatus whereas distal amputation is only indicated for advanced melanomas. In addition to these frequent nail malignancies, nail-specific carcinomas, malignant vascular and osseous tumors, other sarcomas, nail involvement in malignant systemic disorders and metastases may occur. In most cases, they cannot be diagnosed accurately on clinical grounds. Therefore, a high degree of suspicion is necessary in all isolated or single-digit proliferations that do not respond to conservative treatment.     

Acral melanoma foot lesions. Part 1: epidemiology,aetiology, and molecular pathology

Acral melanoma (AM) is a rare subtype of cutaneous malignant melanoma (MM) found on acral skin, primarily on the soles of the feet. Although rare, it is the most common subtype of MM found in patients of African or East Asian ethnicity and has a poor prognosis, often because of the more advanced stage of presentation at diagnosis. The pathogenesis of AM is unclear, but genetic alterations, including mutations in BRAF, NRAS, and KIT have been implicated. Early diagnosis of AM is important for a better prognosis, but its identification is often challenging, leading to easy misdiagnosis. In the first of this two‐part review, we review the history, epidemiology, aetiology and molecular pathology of AM; in part 2 we will review diagnosis and management.     

Guidelines for histopathologic diagnosis of plantar malignant melanoma. Two-dimensional coordination of maximum diameters of lesions and degrees of intraepidermal proliferation of melanocytes

Detection of early lesions of malignant melanoma is highly important for the improvement of the prognosis. However, diagnosis of early malignant melanoma is not easy and is often discordant even among expert dermatopathologists. In this study, we propose guidelines for the histopathologic diagnosis of plantar malignant melanoma and malignant melanoma in situ on the sole. They are formulated with two-dimensional coordination of maximum diameters of the lesions and degrees of intraepidermal proliferation of solitary-arranged melanocytes. The guidelines are simple and reproducible, and surely contribute to the accurate diagnosis of early plantar malignant melanoma.     

Dunkler Nagel

Background

A dark colored pigmentation of nails can be due to a subungual malignant melanoma. There are, however, many other benign causes and this differentiation is an important challenge in dermatological practice.

Problem

When should nail pigmentation be clarified by histological investigations?

Material and methods

This article gives a survey of the literature on this topic and a review of own experiences with clinical case examples. The various causes of melanonychia are presented and criteria for the early recognition of melanoma of the nail matrix are formulated.

Results

The width and depth of color of longitudinal melanonychia do not allow any conclusions on the dignity. If the nail striation is proximally broader than distally, this is evidence of a proliferative event. Confirmation of a subungual hemorrhage does not exclude a malignancy per se. Also detection of pigmentation due to fungi does not exclude the additional presence of a subungual melanoma. A systematic clinical analysis using clear criteria leads to a working diagnosis and suitable treatment.

Conclusion

An early and correct designation of nail pigmentation can avoid unnecessary nail interventions but can also be life saving.     

Dermoscopic features of acral lentiginous melanoma in a large series of 110 cases in a white population

Summary Background Acral lentiginous melanoma (ALM) is a rare but distinctive subtype of melanoma. The diagnosis is often delayed and misdiagnosis is common, due to frequently unusual clinical presentation and a higher rate of amelanosis than in other melanoma subtypes. Objectives We aimed to investigate the dermoscopic features of a large series of ALM in a white‐skinned population, in order to emphasize their diagnostic value. Methods All recorded dermoscopic photographs of ALM, including nail unit variants, were collected from the files of the University Hospital Department of Dermatology (Lyons, France) and reviewed. Results In total 110 lesions, including 66 (60%) palmoplantar ALM and 44 (40%) ALM of the nail apparatus, were analysed for dermoscopic characteristics. The mean Breslow thickness was 2·6 mm. In volar skin melanomas, the two most prevalent patterns were irregular diffuse pigmentation (60%) and the parallel‐ridge pattern (53%). Minor dermoscopic patterns, commonly noted in benign lesions, were also detected but only focally within the lesions. Among the 44 nail unit lesions, 31 (70%) presented irregular lines with variegations in colours, spacing, width and disruption of parallelism. Two cases of melanonychia striata had a triangular shape. Both corresponded to early ungual ALM. Association with subungual haemorrhage was not uncommon. The study included 37 (34%) amelanotic melanomas. However, dermoscopy enabled detection of microscopic remnants of pigmentation in most cases. The vascular pattern found in almost half of these lesions was polymorphous, with combinations of milky‐red areas (95%), linear irregular vessels (49%), dotted vessels (43%) and hairpin vessels (41%). Conclusions The presence of a parallel‐ridge pattern and/or irregular diffuse pigmentation within the lesion is highly indicative of melanoma on volar skin. An irregular lines pattern is the most prominent dermoscopic feature of pigmented ALM of the nail apparatus. Amelanotic ALM either in volar skin or in nail apparatus is characterized by remnants of pigmentation and a polymorphic vascular pattern.     

SPITZ NEVUS

Background. The Spitz nevus is a rare form of benign nevus, which may be confused with malignant melanoma. Methods. We reviewed the clinical and histologic features of 29 cases of Spitz nevus, of which 20 were dealt with by our department of dermatology at the Hull Royal Infirmary between 1969 and 1990. The other nine cases were from the records of our pathology department dated between 1979 and 1991, of which seven of the lesions were excised by the surgeons and two by the general practitioners. Results. In all the cases, the final diagnosis was established histologically. In three cases, there were difficulties histologically in excluding the diagnosis of malignant melanoma. All the lesions were solitary, and none of the lesions recurred following excision despite the possibility of incomplete excision in some cases. Conclusions. We found the size of the lesion and the age of the patient important factors to consider in the diagnosis of Spitz nevus. The small number of cases we encountered over a period of 22 years in a department that serves a population of around 500,000 emphasises the rarity of the condition.     

Malignant Melanoma In situ Arising in the Nail Unit of a Child

A very rare case of malignant melanoma in situ of the nail unit of a child is presented. Clinically, a pigmented streak was present on the finger nail of a 3-year-old girl, and the lesion increased in size and in darkness of the color associated with periungual pigmentation in the following two years. Histopathologically, sections showed proliferation of atypical melanocytes, arranged mostly in single units but some in nests, in and above the basal layer of the epithelium and admixed with long dendrites and a few mitotic figures. Pigmented lesions of nail units of children often show fading or loss of pigmentation clinically; however, a biopsy should be done when they show augmentative changes which clinically suggest malignancy, because subungual malignant melanoma can exist even in children, and proper biopsy can detect it in its early stages.     

Principles of dermatoscopy of pigmented skin lesions

There has been a dramatic increase in the incidence of malignant melanoma in most parts of the world. Because the tumor thickness is the most important prognostic factor for the prognosis of the malignant melanoma, the early detection of thin melanomas is essential. Dermatoscopy allows the physician to discriminate between melanocytic and nonmelanocytic lesions with high diagnostic accuracy and to detect initial malignant melanomas. We review the principles of dermatoscopy and the differential diagnosis of pigmented skin lesions. Before using the ABCD rule of dermatoscopy to classify melanocytic lesions into benign, suspicious, or malignant, the distinction between melanocytic and nonmelanocytic lesions is necessary. An essential prerequisite for the usefulness of this technique is adequate training.     

In vivo study for the discrimination of cancerous and normal skin using fibre probe‐based Raman spectroscopy

Raman spectroscopy has proved its capability as an objective, non‐invasive tool for the detection of various melanoma and non‐melanoma skin cancers (NMSC) in a number of studies. Most publications are based on a Raman microspectroscopic ex vivo approach. In this in vivo clinical evaluation, we apply Raman spectroscopy using a fibre‐coupled probe that allows access to a multitude of affected body sites. The probe design is optimized for epithelial sensitivity, whereby a large part of the detected signal originates from within the epidermal layer's depth down to the basal membrane where early stages of skin cancer develop. Data analysis was performed on measurements of 104 subjects scheduled for excision of lesions suspected of being malignant melanoma (MM) (n = 36), basal cell carcinoma (BCC) (n = 39) and squamous cell carcinoma (SCC) (n = 29). NMSC were discriminated from normal skin with a balanced accuracy of 73% (BCC) and 85% (SCC) using partial least squares discriminant analysis (PLS‐DA). Discriminating MM and pigmented nevi (PN) resulted in a balanced accuracy of 91%. These results lie within the range of comparable in vivo studies and the accuracies achieved by trained dermatologists using dermoscopy. Discrimination proved to be unsuccessful between cancerous lesions and suspicious lesions that had been histopathologically verified as benign by dermoscopy.