Instruments and new technologies for the in vivo diagnosis of melanoma

The principal objective of screening individuals at risk for melanoma is detection of cutaneous melanoma during the curable stages of its early evolution. Unaided visual inspection of the skin is often suboptimal at diagnosing melanoma. Improving the diagnostic accuracy for melanoma remains an area of active research. These research efforts have focused on both the detection of early melanoma and the in-depth evaluation of suspicious pigmented lesions for the presence or absence of melanoma. Numerous instruments are under investigation to determine their usefulness in imaging and ascertaining a correct in vivo diagnosis of melanoma. It is anticipated that some of these tools, alone or in combination, will improve our ability to differentiate, in vivo, melanoma from its simulators. Ultimately, these advances may prevent unnecessary biopsies (increased specificity) while increasing the sensitivity for diagnosing melanoma. This article reviews the current instruments and new technologies for the in vivo diagnosis of melanoma.Learning objective At the conclusion of this learning activity, participants should be acquainted with the instruments designed to facilitate the early detection of melanoma. They should also be familiar with the basic technology behind these instruments and should recognize the potential benefits and limitations inherent in each.     

Self-detected cutaneous melanomas in Italian patients

Self-detection of suspicious pigmented skin lesion combined with rapid referral to dermatologic centres is the key strategy in the fight against melanoma. The investigation of factors associated with pattern of detection of melanoma (self- vs. nonself-detection) may be useful to refine educational strategies for the future. We investigated the frequency of melanoma self-detection in a Mediterranean population at intermediate melanoma risk. A multicentric survey identified 816 consecutive cases of cutaneous melanoma in the period January to December 2001 in 11 Italian clinical centres belonging to the Italian Multidisciplinary Group on Melanoma. All patients filled a standardized questionnaire and were clinically examined by expert dermatologists. Self-detected melanomas were 40.6%, while the remaining lesions were detected by a dermatologist (18.5%), the family physician (15.2%), other specialists (5%), the spouse (12.5%), a friend or someone else (8.2%). Variables associated with self-detected melanomas were female sex, young age, absence of atypical nevi, knowledge of the ABCD rule, habit of performing skin self-examination. Self-detected melanomas did not differ from nonself-detected tumours in term of lesion thickness; however, patients with self-detected melanomas waited a longer period before having a diagnostic confirmation (patient's delay) (> 3 months: odds ratio, 3.89; 95% confidence interval, 2.74-5.53). In order to reduce the patients' delays, educational messages should adequately stress the need for a prompt referral to a physician once a suspicious pigmented lesion is self-detected.     

Multiple synchronous cutaneous melanomas: implications for prevention

BACKGROUND: A subset of about 3-5% of melanoma patients present a second primary melanoma. OBSERVATIONS: We describe two cases of primary multiple synchronous melanomas consecutively observed in the last 6 months in our department in two male patients presenting multiple atypical nevi. In both patients, the second melanoma was diagnosed by the clinician who had identified the first one, but at the time of the first follow-up consultation, 3 months later. The delayed discovery of the second melanoma required another referral for surgery with additional discomfort for the patients. Concern about the first lesion (the thickest in both cases) probably rendered the second one less evident to both patients and clinician, until the first follow-up examination after excision of the first lesion. CONCLUSION: We stress the need for careful and thorough examination of the whole body surface at the time of detection of a cutaneous melanoma in subjects with multiple atypical moles because the finding of synchronous multiple melanomas is not uncommon.     

Primary cutaneous polypoidal non-stageable melanomas in Queensland

Patients who develop a polypoidal melanoma which does not appear to invade the reticular dermis have a poor prognosis. Thirty three or 2-1% of 1607 patients treated for melanoma, in Queensland (1963–1969) had a polypoidal non-stageable melanoma. Twenty two patients were men. Four patients (12% of the thirty three) developed a second melanoma. Of the, thirty three patients, twenty one [sixteen men, five women) died from melanoma within jour years of the initial treatment. One man was lost to follow-up after fourteen months. Another man died eleven years after treatment. The ten patients [jour men, six women) surviving have been followed for a mean time of 113 months [86—133) and were reported free of melanoma at their last check-up. It is preferable to excise polypoidal skin lesions which look like atypical telangiectatic granulomas (pyogenic granulomas) or other unusual-looking benign pedunculated skin tumours rather than to treat by curettage so that adequate material is available for histological examination.     

Immunohistochemical expression of retinoblastoma protein in cutaneous melanomas

Retinoblastoma protein (pRB) is the product of a tumour-suppressor gene (rb) mapped to chromosome 1 3q14. pRB acts as a control checkpoint at the G₁ phase of the cell cycle, preventing cells from entering into the S phase. Mutational inactivation of both normal alleles leads to loss of pRB expression and the development of malignant neoplasms. Absence of pRB occurs in retinoblastomas, sarcomas and several other types of tumours. The potential role of pRB in the pathogenesis of cutaneous melanoma is unknown, and was the subject of this investigation. Formalin-fixed, paraffin-embedded sections of four cutaneous melanoma metastases, 17 primary invasive melanomas and 10 predominantly intradermal melanocytic naevi were studied. Monoclonal antibodies directed against pRB and K1-67 antigen were used after microwave beating of sections to restore antigenicity. pRB was not detected in morphologically normal epidermal melanocytes. In five naevi, only scattered cells (1%) expressed pRB, whereas in the other five naevi, pRB expression was undetectable. In contrast, pRB was detected in all primary and metastatic melanomas (5–70% of cells). Expression was always localized to nuclei. Ki-67 expression was detected only in the melanomas, with both cellular staining and regional localization similar to that shown by pRB in 13 of the 20 melanomas studied with both antibodies. pRB appears to be expressed at higher levels in melanomas than in benign naevi. It therefore seems unlikely that loss of rb expression is in important factor in the pathogenesis of melanoma.     

Nestin expression in cutaneous melanomas and melanocytic nevi

BACKGROUND: Nestin is one of the intermediate filaments that are expressed in proliferating neural progenitor cells during development of the central nervous system (CNS) and peripheral nervous system. Postnatal re-expression of the protein occurs mainly under pathological conditions, including injury and neoplasia. In this study, nestin expression was detected in both benign and malignant melanocytic skin lesions and its diagnostic relevance was then evaluated. METHODS: Altogether 139 bioptic tissue samples consisting of 42 nodular melanomas, 32 superficial spreading melanomas, 12 metastatic melanomas, 10 dysplastic nevi and 43 common melanocytic intradermal and dermoepidermal nevi were analysed using indirect immunohistochemical staining. RESULTS: We demonstrated that nestin immunostaining was significantly increased in melanomas where it correlated with more advanced stages of the disease. CONCLUSION: We conclude that expression of the intermediate filament protein nestin might be an indicator of tumor dedifferentiation and more aggressive behaviour. Furthermore, we suggest that nestin might be a relevant marker of tumorous and non-tumorous angiogenesis.     

Current and emerging technologies in melanoma diagnosis: the state of the art

Relative to other specialties, dermatologists have been slow to adopt advanced technologic diagnostic aids. Most skin disease can be diagnosed by simple visual inspection, and the skin is readily accessible for a diagnostic biopsy. Diagnostic aids, such as total body photography and dermoscopy, improve the clinician's ability to diagnose melanoma beyond unaided visual inspection, however, and are now considered mainstream methods for early detection. Emerging technologies such as in vivo reflectance confocal microscopy are currently being investigated to determine their utility for noninvasive diagnosis of melanoma. This review summarizes the currently available cutaneous imaging devices and new frontiers in noninvasive diagnosis of skin disease. We anticipate that multimodal systems that combine different imaging technologies will further improve our ability to detect, at the bedside, melanoma at an earlier stage.     

Bim expression is reduced in human cutaneous melanomas

Bim is a BH3-only protein belonging to the Bcl-2 family of apoptotic regulators. Upon activation, Bim can antagonize all the prosurvival Bcl-2 proteins, leading to apoptosis. To investigate whether Bim plays a role in melanoma progression, we used tissue microarray and immunohistochemistry to measure Bim expression in 52 cases of dysplastic nevi, 159 cases of primary melanomas and 52 cases of melanoma metastases, and evaluated the prognostic value of Bim expression. Our results showed that Bim expression is reduced as melanoma progresses. Significant differences for Bim staining pattern were observed between dysplastic nevi and metastatic melanomas (P<0.001, chi2 test), and between primary melanomas and metastatic melanomas (P<0.001, chi2 test). Moreover, reduced Bim expression is significantly correlated with poor 5-year survival of melanoma patients but failed to be an independent prognostic factor by Cox regression analysis. Our data suggest that Bim loss may play an important role in melanoma progression.     

The importance of self-examination in the earliest diagnosis of multiple primary cutaneous melanomas: a report of 47 cases

BACKGROUND: Development of more than one primary melanoma in a patient is a relatively uncommon but well-recognized phenomenon. Its frequency has ranged from 1.2% to 8.2% in several series. This subgroup of patients with multiple primary lesions has not been characterized sufficiently. We report the experience of the Melanoma Unit of University Hospital Spedali Civili of Brescia, Italy. METHOD: Study subjects were drawn from 1240 patients with histologically confirmed melanoma, including melanoma in situ. From this group, multiple melanomas developed in 47 patients (3.79%). Every one of our patients has been taught to perform self-examination of the skin to detect suspicious pigmented lesions. RESULTS: Of the 47 patients described in this study, 38 had two primary melanomas, 7 had three melanomas and 2 had 5 and 10 melanomas, respectively. Mean age at first diagnosis was 46.2 years. The majority of subsequent melanomas (74.5%) were removed within 5 years of the initial operation. Synchronous lesions were found in 10 patients. In male patients, the lesion appeared most frequently on the trunk; in female patients, melanoma appeared mostly on the lower extremities. The second primary melanomas developed in the same anatomic region from the first in 53.2% of our patients. The proportion of in situ to invasive melanomas was greater for the second melanomas compared with the first melanomas. Regarding invasive melanomas, the mean thickness of the first melanomas was 1.31 mm compared with 0.66 mm for the second ones. Dividing patients into two groups, of more and less than 50, it is highlighted that in older patients synchronous lesions appear more frequently (36.4% vs. 8.0%); the median time interval between sequential melanomas is longer (84 vs. 63.7 months); and the ratio between the primary and secondary melanoma mean thickness is lower (1.21 : 1.08 vs. 1.43 : 0.63 mm). CONCLUSIONS: The study confirms that second primary melanoma is usually thinner than the first lesion, and it is more common in the same region of the body as the initial melanoma. The highest risk for a second melanoma is during the first 5 years, but a much longer time interval of 28 years is possible. Continued medical follow-up with complete skin examinations seems prudent, but it is very important to promote self-skin evaluation in patients to detect not only metastases but also subsequent primary melanomas in their earliest phases.     

Study of formaldehyde-induced fluorescence in cutaneous melanomas and naevi

We have investigated 16 cases of cutaneous malignant melanomas and 34 cases of various types of neavi for formaldehyde-induced fluorescence. All cutaneous malignant melanomas (100%), but only two out of 34 naevi (5.88%) showed FIF positivity. The significance of this finding as a predictor of biological behaviour is discussed.     

Accuracy of the clinical diagnosis in malignant melanomas

Histologic findings and clinical data of 411 patients with malignant melanomas treated in 1952 up to june 1977 reveal an improvement of diagnostic accuracy. Within the last years, fewer patients were referred to the clinic with extensive tumor growth or with metastases. A change from the levels of invasion V and IV to III is evident. Further improvement to level II and I with a corresponding smaller tumor thickness is appearing in outlines.     

Dermatoscopic pitfalls in differentiating pigmented Spitz naevi from cutaneous melanomas

Epiluminescence microscopy (ELM, skin surface microscopy, dermoscopy, dermatoscopy) is a valuable method for improving the diagnostic accuracy in pigmented skin lesions. Specific ELM criteria are already recognized for differentiating pigmented Spitz naevi (PSN) from cutaneous melanomas (CM). Our purpose was to describe the ELM appearance of a series of PSN with emphasis on PSN and CM with overlapping features. Thirty-six consecutive patients with PSN, and three cases of CM (selected from a larger database) exhibiting ELM 'spitzoid' features, were evaluated clinically, dermatoscopically and histopathologically. Most PSN (27 of 36; 75%) displayed two typical ELM patterns, namely, the starburst (19 of 36; 53%) or the globular pattern (eight of 36; 22%), which were correlated to different histopathological findings. In nine of 36 (25%) PSN, atypical ELM features which are more commonly seen in CM were observed. These PSN with an atypical pattern were characterized by an uneven distribution of colours and structures, and an irregular diffuse pigmentation resembling blue-white veil or irregular extensions (black blotches). These atypical lesions mostly occurred in children and showed no history of growth. In contrast, in three examples of CM, the typical ELM criteria of malignancy were less recognizable and either the characteristic starburst or globular pattern usually seen in PSN was present. These three lesions occurred in adults and had a recent history of change in colour, shape or size. The overlap in ELM features of some PSN and CM represents a major diagnostic pitfall when ELM examination is considered alone. In these atypical cases, clinical history including the age of the patient may be the only clue to enable a correct diagnosis.     

Clinical diagnosis of early malignant melanomas

Criteria for the clinical diagnosis of early malignant melanomas were sought. A total of 213 pigmented tumors, clinically suspected of being early malignant melanomas, were measured, described, photographed, and classified histologically: 40 proved to be definitely malignant, 49 possibly malignant ("dysplastic"), and 124 definitely benign (mostly melano-/nevocytic nevi, spindle-cell nevi, and Spitz nevi). Malignant melanomas had a horizontal diameter of greater than 5 mm, the patients were older than 18 years, and 62.5% were females. A combination of criteria allowed a clinical diagnosis to be made with an accuracy of 76.2%. The criteria of a horizontal diameter of greater than 5 mm, irregular configuration, and uneven pigmentation permitted 80% of all melanomas to be identified. Histologically atypical, dysplastic nevi could not be diagnosed clinically. They probably constitute a heterogeneous group and only some of them appear to be very early, histologically not clearly recognizable, malignant melanomas.     

Key points in dermoscopy for diagnosis of melanomas, including difficult to diagnose melanomas, on the trunk and extremities

Early diagnosis and prompt surgical excision are the most important aims in the secondary prevention of cutaneous melanoma. Dermoscopy has increased the accuracy in the detection of melanoma because of dermoscopic-specific features that can be easily detected by trained dermoscopists. However, the classical melanoma-specific criteria such as multicomponent pattern, atypical pigmented network, irregular dots/globules, irregular streaks, multiple colors, blue-whitish veil or regression structures may not be present in all of these lesions. For some early melanomas change, as evidenced by sequential dermoscopic monitoring, may be the only feature suggesting malignancy. At present, even with dermoscopy, the diagnosis of these early melanomas remains to be a challenge for dermatologist. Patient education, digital dermoscopic follow up and consensus diagnosis have been proposed to overcome this problem.     

Clinical and histological features of poor prognosis in cutaneous metastatic melanomas

Patients with melanoma metastatic to the skin show variable prognosis. Though some may survive for quite a long time, some die of disseminated disease within 1 year of removal of cutaneous metastases. The aim of this study was to find out whether there are any histological criteria indicating particular poor outcome. Clinical and histological features of 344 melanoma lesions metastatic to the skin were assessed and their prognostic relevance was investigated. H&E stained histological slides were scanned for the presence of morphological criteria expressing certain tumor cell - stroma interactions: capsule formation (CAPSULE), formation of intratumoral septa (NEWSEPTA), simple invasion between collagen of reticular dermis (DERM-SIMPLE), or subcutis (SCSIMPLE), preservation of preexistent collagen (PRECOLL) or fatty tissue (PREFAT) and, finally, histological site of metastasis. Additionally, anatomical location of the metastases, time between removal of primary tumor and metastases, age and sex of patients were recorded. The metastases were divided into two groups: lesions of patients who died within 1 year after resection (n=59) and lesions from patients with a longer survival (n=285). Metastases which were associated with death within one year were significantly more often found in male patients (54.2% versus 34.7%), in younger patients (mean age 51.1±14.1 years versus 58.8 ± 15.3 years), had developed earlier after the primary tumor (mean time of 21.7±19.9 months versus 43.3±27.4 months) and were more often found at distant sites than in localregional sites (45.7% versus 30.5%), and were more often involved in the subcutis (74.5% versus 56.1%). From a histological point of view, DERMSIMPLE (80% versus 46%; p<0.001) and PRECOLL (82.8% versus 57.6; p<0.01) were more frequent in metastases of poor outcome. The same was true for SCSIMPLE (50% versus 25.6%; p<0.01) and PREFAT (68.1% versus 46.8%; p<0.05) in lesion with subcutaneous growth, whereas CAPSULE (54.5% versus 75%) was less frequently seen. In conclusion, melanoma deposits metastatic to the skin with particular poor outcome differ clinically and histologically from other cutaneous melanoma metastases. This should be taken into account in the design of therapeutic clinical trials.     

Reflectance-mode confocal microscopy for the in vivo characterization of pagetoid melanocytosis in melanomas and nevi

Pagetoid infiltration of the epidermis by melanocytes is a relevant criterion for the histologic diagnosis of melanoma, although sporadically observable in benign lesions. Since in vivo reflectance-mode confocal microscopy enables the visualization of superficial layers at cellular-level resolution, the different aspects and the diagnostic significance of epidermal alterations and pagetoid cell infiltration were investigated on 84 benign and malignant melanocytic lesions by confocal microscopy and compared with histopathology. The observation of a disarranged pattern in superficial layers appeared characteristic for malignant lesions. In vivo identification of pagetoid cells, clearly present in the majority of melanomas and in a few benign lesions, seemed useful for melanoma diagnosis. An excellent concordance between confocal microscopy and histopathology was achieved. Moreover, identification of some characteristic features by confocal microscopy, such as large and numerous closely arranged cells extended to the stratum corneum, was strongly correlated with malignancy. In conclusion, confocal microscopy enabled a very good identification of melanocytes spreading upward in a pagetoid fashion in melanocytic lesions. Thus, when pagetoid melanocytosis is observable by means of confocal microscopy, melanoma diagnosis should be considered, whereas it cannot be excluded in the absence of pagetoid cells, lacking in at least 10% of malignant lesions.