Seborrhoeic keratoses with associated lesions: a retrospective analysis of 85 lesions

Clinical Misdiagnosis of Cutaneous Malignant Tumors as Melanocytic Nevi or Seborrheic Keratosis: A Retrospective Analysis of a Chinese Population

Purpose

The rising incidence and mortality associated with cutaneous malignant tumours highlight the importance of early diagnosis of these tumors. In clinical practice, these tumors are often misdiagnosed as benign skin lesions such as melanocytic nevi (MN) and seborrheic keratosis (SK) because of their similar morphologic features. The incidence and clinicopathological subtypes of cutaneous malignancies in East Asia populations significantly differ from those in fair-skinned groups. However, studies on misdiagnoses in Eastern countries are lacking. Therefore, this study focused on the clinical and pathological features of cutaneous malignant tumors misdiagnosed as MN or SK in a Chinese population.

Patients and Methods

A total of 4592 samples clinically diagnosed as MN (n = 3503) or SK (n = 1089) from July 2014 to June 2022 were collected and evaluated retrospectively. The clinical and pathological data were analyzed to identify associated factors.

Results

Pathological assessments showed that 2.5% (86/3503) of the specimens clinically diagnosed as MN were malignancies, predominantly basal cell carcinoma (BCC, 84.9%, 73/86), followed by malignant melanoma (MM, 8.1%, 7/86) and squamous cell carcinoma (SCC, 7.0%, 6/86). Similarly, 5.7% (62/1089) of the specimens clinically diagnosed as SK were malignant tumors, of which BCC (50.0%, 31/62) was the most common, followed by SCC (41.9%, 26/62) and MM (8.1%, 5/62). In both types of specimens, advanced age and facial lesions were risk factors for malignancy misdiagnosis. The malignancy rate, mean age, and proportion of SCC in the specimens clinically diagnosed as SK were higher than those in the specimens clinically diagnosed as MN. Dermoscopy significantly reduced the rate of misdiagnosis of these tumors as MN or SK.

Conclusion

In China, cutaneous malignant tumors misdiagnosed as MN or SK are not uncommon in clinical practice, and active introduction of noninvasive diagnostic techniques is essential to distinguish them.

Seborrheic Keratosis With Malignant Transformation (Invasive or Noninvasive Squamous Cell Carcinoma Arising in Seborrheic Keratosis): A Clinicopathologic and Immunohistochemical Study of 11 Cases

ABSTRACT

Seborrheic keratosis is a common benign neoplasm composed of basaloid keratinocytes. However, little is known about the malignant transformation of the tumor. Eleven cases of seborrheic keratosis with malignant transformation were analyzed. The 11 patients included 5 male patients and 6 female patients with a median age of 75 years at diagnosis (68-90 years). The tumors arose at various sites from the scalp (n = 3) to the lower leg (n = 2). The median tumor size was 12 (10-32) and 40 (20-75) mm in 7 noninvasive and 4 invasive cases, respectively. One patient exhibited in-transit skin metastasis. Histopathology of the malignant components resembled porocarcinoma or inverted follicular keratosis. Bowenoid and pagetoid spreading was frequently observed. The malignant components expressed cytokeratin 5/6 (100%) and GATA3 (73%), but not cytokeratin 7 (0%), cytokeratin 19 (9%), BerEP4 (0%), c-kit (0%), and NUT (0%). No significant immunoreactivity of YAP1 was observed in any of the cases. Mutant-type immunostaining of p53 and PTEN was observed in 91% and 82% of the cases, respectively. An increase in p16 expression was seen in 6 (86%) of the 7 cases with noninvasive carcinoma, although a loss of p16 immunoexpression was seen in the invasive carcinoma component in 3 (75%) of the 4 cases. This study demonstrated that seborrheic keratosis can undergo malignant transformation, particularly in large-sized lesions in elderly patients. Malignant components mimic porocarcinoma or inverted follicular keratosis. Malignant transformation induced by TP53 and PTEN mutations and tumor invasion by CDKN2A inactivating mutations are suggested in this study.

Clonal-pattern Seborrheic Keratosis: Risk of Recurrence and Progression to Carcinoma

Seborrheic keratosis is a benign epidermal tumor. Seborrheic keratosis with clonal pattern (CPSK) displays histologic features distinct from other subtypes of SK (non-CPSK). We sought to quantitatively assess the risk of recurrence and progression to squamous cell carcinoma (SCC), either in situ or invasive, of incompletely excised CPSKs. We studied all 244 cases from 238 patients of "seborrheic keratosis, clonal pattern" diagnosed in our institution over a 10-year period (2008-2018). Demographic, clinical, pathologic, and follow-up data were gleaned from electronic health records. Following glass slide review, CPSK lesions were divided into 2 groups: CPSK with cytologic atypia and CPSK without cytologic atypia. For comparison, 107 non-CPSKs were studied as controls. The minimum follow-up period was 2 years (median=4 y). All lesions were incompletely excised. Eighteen of 244 CPSKs (7.4%) recurred at or adjacent to the site of initial partial removal compared with 1.9% of non-CPSKs. Five of the 18 (28%) recurrent CPSKs recurred as CPSK, 11 (61%) as SCC in situ, and 3 (17%) as invasive SCC. The mean time to recurrence was 3.1 years. Two non-CPSKs recurred as non-CPSKs. Overall CPSKs were more likely to recur than non-CPSKs ( P =0.04). CPSKs with atypia were more likely to recur than CPSKs without atypia ( P =0.03). The upgrade rate to SCC at least in situ of all recurrent CPSK lesions with atypia was 78%. Our results suggest that pathologists should report the presence of clonal pattern when observed in seborrheic keratoses, indicate the presence of atypia, and provide lesional margin assessment.

Clinical and Histopathological Characteristics of Tumors Arising in Seborrheic Keratosis: A Study of 1365 Cases

Objective

The aim of this study was to describe the clinical and histopathological characteristics of seborrheic keratosis (SK) with secondary tumor and identify associated factors.

Methods

This study was a monocentric retrospective case-control study describing the factors associated with the development of tumors in SK. A total of 1365 patients with SK were admitted to our department between 2018 and 2021. All of the histopathological specimens and medical records of these patients were reviewed. We compared the data of 36 patients with tumors arising in SK with those of the remaining 1329 patients with only SK, which were designated the control group.

Results

The incidence of tumors arising in SK that were biopsied was 2.6%. The tumor types included squamous cell carcinoma (SCC), basal cell carcinoma (BCC) and keratoacanthoma (KA). Compared with other patients with SK, elderly patients with immunosuppression, patients presenting surrounding erythema or ulceration, and those with SK in exposed areas had an increased possibility of developing a secondary tumor. Tumors arising within SK have the histopathological features of ulceration, cytologic atypia, mitosis, “malignant horn”, trabecular cell cords, solar elastosis and severe inflammatory infiltration in the dermis.

Conclusion

SK can show malignant progression in a small fraction of SK cases that are biopsied. This study is the first report on the clinical and histopathological characteristics of tumors arising in SK and identifies relevant factors in an Asian population.

Photodynamic therapy combined with carbon dioxide laser for successful treatment of cutaneous squamous cell carcinoma within a long-standing and huge seborrheic keratosis

Seborrheic keratosis (SK) is a common benign lesion in which malignancies like cutaneous squamous cell carcinoma (cSCC) can arise rarely. We report a case of an 81-year-old man who presented a well-demarcated reddish-brown plaque with central raised coarse nodules on the top of his head. Dermoscopy and reflectance confocal microscopy (RCM) showed the possibility of malignant transformation. cSCC was confirmed by histopathology and immunohistochemistry. Considering the fact of local low-risk cSCC within a large SK lesion, carbon dioxide (CO₂) laser was used to treat the SK lesion, and reduce the thickness of local cSCC simultaneously. Three sessions of 5-aminolevulinic acid-mediated photodynamic therapy (ALA-PDT) were performed after CO₂ laser. Finally, no atypical cells were found by multi-point biopsy after treatment, and follow-up was continued for one year. Therefore, malignant changes of SK are relatively uncommon, but should be suspected when abnormal appearance or symptoms occurred. ALA-PDT combined with CO₂ is a safe, effective, and minimally invasive treatment for cSCC arising from a huge SK.

Comparison of Dermoscopic Features Between Melanoacanthomas and Melanoacanthoma-Like Malignant Melanomas in Korean Patients

BACKGROUND

A melanoacanthoma (MA) is a pigmented variant of seborrheic keratosis. Owing to the pigmentation, MAs may mimic the clinical appearance of malignant melanomas (MMs). However, the dermoscopic patterns of MAs and MA-like MMs have rarely been compared.

OBJECTIVE

To elucidate the clinical and dermoscopic differences between MAs and MA-like MMs.

METHODS

This study included 77 MA and 33 MA-like MM patients. We retrospectively reviewed the medical records, clinical findings, and dermoscopic findings of the two groups.

RESULTS

Crypts and comedo-like openings (71.4%) in MAs and the blue-white veil (60.6%) in MMs were the most common dermoscopic findings. Crypts, comedo-like opening, milia-like cysts, fissures, and hairpin vessels appeared more frequently in MAs (P < .05). However, atypical pigment networks, blue-white veils, pseudopods and streaks, and atypical vessels were more common in MMs (P < .05). MAs often showed melanoma-specific dermoscopic findings, especially blue-white veils (22.1%). Furthermore, fissures (42.4%), crypts (21.2%), and comedo-like openings (15.2%) were observed in MMs, although they are typically benign patterns.

CONCLUSION

Differences in dermoscopic patterns might provide important clues for the differential diagnosis of MA-like lesions. However, MAs such as MMs and true-benign MAs may overlap clinically in appearance and on dermoscopy. Several benign patterns were frequently observed in MMs (fissures, globular pattern, crypts, comedo-like openings, cerebriform appearance, and milia-like cysts), and several malignant patterns were observed in MAs (blue-white veil, pseudopod, and atypical pigment network). Importantly, if any of the melanoma-associated features or atypical vessels are present, the lesion should be biopsied to establish a diagnosis.

Seborrheic Keratosis or Squamous Carcinoma? Clinical Examination versus Biopsy: The Importance of Criticism

We compare the results of clinical observation and histopathology analysis for developing a differential diagnosis of seborrheic keratosis (SK) of the external auditory canal (EAC). A 46-year-old man with a history of a recurrent lesion in the EAC underwent clinical observation of the skin lesion's appearance, computed tomography (CT) scan, magnetic resonance imaging (MRI), and several biopsies. Initially, a benign form of SK was diagnosed based on several biopsies performed over a 10-year period. The lesion's appearance was consistent with a malignant disease, which led the clinician to perform a CT scan and an MRI scan. The patient underwent partial petrosectomy to completely remove the lesion as CT and MRI scans showed an infiltrative process. Squamous carcinoma was the final histological diagnosis. The patient was disease free at 1 year of follow-up after petrosectomy. In conclusion, if there are inconsistencies between clinical observation and histological report, additional tests should be performed to exclude the malignity of a lesion.

Clonal seborrheic keratosis: a rare skin tumor

Seborrheic keratosis is a benign epidermal neoplasm, representing one of the most common skin tumors. Clonal seborrheic keratosis is one of the histological subtypes of this entity. It is an uncommon lesion which may resemble other benign or malignant lesion. We report a case of a 60-year-old woman presented with a 7 year history of a gradually growing, cutaneous lesion on her left arm. On physical examination, the lesion was elevated, well-circumscribed, measuring 5 cm in maximum diameter. The tumor was biopsied. Histopathological examination revealed the presence of well-defined nests of clear-looking or basaloid keratinocytes within an acanthotic epidermis, corresponding to the Borst-Jadassohn phenomenon. The tumor cells were small and monomorphic. We diagnosed this tumor as clonal seborrheic keratosis. Although surgical excision was recommended, our patient refused an operation. This case of clonal seborrheic keratosis is presented for its rarity and for differential diagnosis.

Dermoscopic Clues for Diagnosing Melanomas That Resemble Seborrheic Keratosis

Importance

Melanomas that clinically mimic seborrheic keratosis (SK) can delay diagnosis and adequate treatment. However, little is known about the value of dermoscopy in recognizing these difficult-to-diagnose melanomas.

Objective

To describe the dermoscopic features of SK-like melanomas to understand their clinical morphology.

Design, Setting, and Participants

This observational retrospective study used 134 clinical and dermoscopic images of histopathologically proven melanomas in 134 patients treated in 9 skin cancer centers in Spain, France, Italy, and Austria. Without knowledge that the definite diagnosis for all the lesions was melanoma, 2 dermoscopy-trained observers evaluated the clinical descriptions and 48 dermoscopic features (including all melanocytic and nonmelanocytic criteria) of all 134 images and classified each dermoscopically as SK or not SK. The total dermoscopy score and the 7-point checklist score were assessed. Images of the lesions and patient data were collected from July 15, 2013, through July 31, 2014.

Main Outcomes and Measures

Frequencies of specific morphologic patterns of (clinically and dermoscopically) SK-like melanomas, patient demographics, and interobserver agreement of criteria were evaluated.

Results

Of the 134 cases collected from 72 men and 61 women, all of whom were white and who had a mean (SD) age of 55.6 (17.5) years, 110 (82.1%) revealed dermoscopic features suggestive of melanoma, including pigment network (74 [55.2%]), blue-white veil (72 [53.7%]), globules and dots (68 [50.7%]), pseudopods or streaks (47 [35.1%]), and blue-black sign (43 [32.3%]). The remaining 24 cases (17.9%) were considered likely SKs, even by dermoscopy. Overall, lesions showed a scaly and hyperkeratotic surface (45 [33.6%]), yellowish keratin (42 [31.3%]), comedo-like openings (41 [30.5%]), and milia-like cysts (30 [22.4%]). The entire sample achieved a mean (SD) total dermoscopy score of 4.7 (1.6) and a 7-point checklist score of 4.4 (2.3), while dermoscopically SK-like melanomas achieved a total dermoscopy score of only 4.2 (1.3) and a 7-point checklist score of 2.0 (1.9), both in the range of benignity. The most helpful criteria in correctly diagnosing SK-like melanomas were the presence of blue-white veil, pseudopods or streaks, and pigment network. Multivariate analysis found only the blue-black sign to be significantly associated with a correct diagnosis, while hyperkeratosis and fissures and ridges were independent risk markers of dermoscopically SK-like melanomas.

Conclusions and Relevance

Seborrheic keratosis-like melanomas can be dermoscopically challenging, but the presence of the blue-black sign, pigment network, pseudopods or streaks, and/or blue-white veil, despite the presence of other SK features, allows the correct diagnosis of most of the difficult melanoma cases.

Spindle cell squamous cell carcinoma arising in Bowen's disease: Case report and review of the published work

A 79-year-old Japanese woman presented with an ulcerated, brown-red nodule in the center of a sharply demarcated, tan-brown plaque situated on the left side of her right breast. Histologically, the plaque demonstrated an acanthosis with an intraepidermal epithelioma of Borst-Jadassohn. Small oval nests of bland-appearing basophilic cells in the periphery gradually enlarged into nests of various sizes and irregular shapes, composed of densely cohesive, atypical basophilic cells above the central nodule. The atypical keratinocytes shifted to atypical spindle cells beneath the acanthotic epidermis, penetrating deep into the subcutaneous tissue. In addition to vimentin and p63, the spindle cells were positive for several cytokeratin (CK) markers, including AE1/AE3, 34βE12 and CK5/6, which showed more intense signals closer to the epidermis. Basophilic cells in the clonal nests were positive for p63, AE1/AE3, 34βE12 and CK5/6. The MIB-1 index was estimated at approximately 40-50% in both the bland-appearing and the atypical basophilic cells. We describe the first case of spindle cell squamous cell carcinoma arising in an intraepidermal epithelioma expressed by clonal Bowen's disease, which was difficult to differentiate from clonal seborrheic keratosis.

Nodulocystic Basal Cell Carcinoma Arising Directly from a Seborrheic Keratosis: A Rare Case Report

Seborrheic keratoses (SKs) are common epidermal tumors composed of benign keratinocytes. Malignant skin tumors including basal cell carcinoma (BCC) rarely arise within SKs. We report a rare case of an 82-year-old man with nodulocystic BCC that appeared at the center of a scaly hyperpigmented SK that had been presented for more than 10 years. It was histologically confirmed that CK19-positive BCC arose directly from the wall of the pseudohorn cyst, a part of the SK. Nodular and/or cystic BCC also rarely arise within SKs while the most common histologic type of BCC within SKs is the superficial type. Careful observation of SKs is important even though it is rarely a background condition for malignant transformation.

Seborrheic keratosis: current concepts of pathogenesis

The article covers problems of seborrheic keratosis. The authors discuss current concepts of the etiology and pathogenesis of the disease paying special attention to the histology and immunohistochemistry of different forms and diverse clinical presentations. They describe Leser - Trelat syndrome as well as potential neoplastic transformation of seborrheic keratomas and their association with malignant skin neoplasms.

Basal Cell Carcinoma Arising within Seborrheic Keratosis

Malignant tumour development within a seborrheic keratosis (SK) is extremely rare. Though the most commonly developed malignant tumour is the basal cell carcinoma (BCC), other tumour types have also been reported in literature. Herein, we will report a superficial type BCC case developed within SK localized in hairy skin of a 78-year-old female patient. In immunohistochemical evaluation, diffuse positive staining with CK19 and over-expression in p53 compared with non-neoplastic areas were determined in neoplastic basaloid islands. It is always not easy to differentiate especially superficial type BCC cases from non-neoplastic epithelium of SK with histopathological evaluation. As far as this reason we believe that in difficult differentiation of these 2 lesions, in order to show the differentiation in basal epithelium, immunohistochemical evaluation may be helpful.

Dysplastic nevus associated with seborrheic keratosis

Seborrheic keratosis is a common skin lesion which may coincidentally be associated melanocytic nevi. The authors describe a case of dysplastic nevus associated with seborrheic keratosis and discuss the clinical, dermoscopic, and histological findings of this association. They also discuss the association between seborrheic keratosis and other benign and malignant tumours.

Endothelin-1 enhances the melanogenesis via MITF-GPNMB pathway

Endothelin-1 (ET-1) plays an indispensable role in epidermal pigmentation in hyperpigmentary disorders due to a central role in melanogenesis. Nevertheless, precise mechanism involved in ET-1-induced hyperpigmentation is still undefined. Glycoprotein (transmembrane) non-metastatic melanoma protein b (GPNMB) is a key element in melanosome formation. Therefore, we speculated that GPNMB was correlated with ET-1-induced pigmentation. After culturing with ET-1, melanin synthesis was significantly up-regulated, accompanying with increased expression of GPNMB and microphthalmia-associated transcription factor (MITF). Total number of melanosomes and melanin synthesis were sharply reduced via GPNMB-siRNA transfection, indicating ET-1-induced pigmentation by GPNMB-dependent manner. Furthermore, MITFsiRNA transfection strikingly inhibited GPNMB expression and the melanogenesis, and this suppression failed to be alleviated by ET-1 stimulation. All of these results demonstrated that ET-1 can trigger melanogenesis via the MITF-regulated GPNMB pathway. Taken together, these findings will provide a new explanation of how ET-1 induces hyperpigmentation, and possibly supply a new strategy for cosmetic studies. [BMB Reports 2013; 46(7): 364-369]

Malignant change in seborrhoeic keratoses in a region with high solar ultraviolet levels

Regions with high solar UV levels and high skin cancer rates may experience a greater incidence of malignancy in association with seborrhoeic keratoses (SebK) than in low UV regions. Previous reports have indicated that basal cell carcinoma is the most common neoplasm with reported rates of up to 4 per cent of excised SebK. The rates of such compound lesions occurring in our practice were reviewed, indicating that Bowen's disease was the most frequently observed neoplasm with a rate of 7 per cent. In total, 10 per cent of all excised specimens showed either frank malignancy or some degree of atypia.

Association between melanocytic neoplasms and seborrheic keratosis: more than a coincidental collision?

Clinical observations and an expanding knowledge of cell-to-cell communication have led us to speculate that the finding of a melanocytic nevus in conjunction with a seborrheic keratosis is more than a coincidental collision of two lesions. Here we present five cases demonstrating dermoscopic features of both melanocytic lesions and seborrheic keratoses with corresponding histology. Four cases demonstrate dermoscopic features of a melanocytic nevus and seborrheic keratosis, and the final case a melanoma arising in association with a seborrheic keratosis.

Basal cell carcinoma arising within a seborrheic keratosis with respect to immunohistochemical characteristics

Malignant tumor occurring within seborrheic keratosis (SK), which is one of the most common benign cutaneous tumors, is extremely rare. We report a case of basal cell carcinoma (BCC) arising within SK. Additionally, this is the first study to describe the immunohistochemical characteristics of this type of carcinoma. An 89-year-old Japanese woman presented with a persistent scaly plaque in the right auricle of her ear. Histopathological study revealed a superficial type of BCC arising within SK. Immunohistochemical studies showed that cytokeratin 17 (CK17), CK19, SOX9 and p53 protein were expressed in BCC, but not in SK. BCC is considered to originate from the follicular germinative cells, and the outer root sheath may be the possible origin. SK is also thought to be a benign skin appendage neoplasm showing follicular differentiation, especially follicular infundibula. Therefore, previous reports speculated that there was a pathogenic relationship between SK and BCC, with respect to a common follicular origin. However, the immunohistochemical characteristics of this study suggest that BCC does not arise directly from SK, but instead, that SK is the nidus of the carcinoma, resulting in the abutment of SK with BCC. Furthermore, the results of the present case suggest that immunohistochemical surveillance of the expression of CK17, CK19 and SOX9 and p53 protein is useful in differentiating minute BCC from the non-neoplastic hair buds.

Cyclin-dependent kinase 2 (CDK-2) expression in nonmelanocytic human cutaneous lesions

Lesions originating from different types of skin cells differ significantly with respect to their pathologic importance. The aim of this work was to examine as to what extent the differences in the origin are reflected in expression levels of CDK-2 and to investigate whether CDK-2 expression might be considered as potential marker useful for diagnostics and assessment of invasiveness of human nonmelanocytic lesions. We conducted comparative immunohistochemical studies of expression of cyclin-dependent kinase 2 (CDK-2) in 16 benign epithelial skin lesions, 11 precancerous lesions, 19 cases of basal cell carcinoma (first such study), 14 squamous cell carcinomas (SCCs), and 7 fibromas. Development of benign epithelial skin lesions was not associated with considerable increase of the CDK-2 expression. Increase of the CDK-2 level was observed in precancerous lesions, and the expression was strongest in SCCs. The level of CDK-2 may be related to invasiveness of skin cancers, as squamous cell carcinomas expressed the enzyme significantly stronger than basal cell carcinomas. Higher percentage fraction of CDK-2 positive cells observed in SCC compared with precancerous lesions may be useful for histopathologic diagnostics of this cancer. Moreover, strong immunohistochemical CDK-2 staining of the cancer cells present deep in dermis may facilitate their detection in histopathologic examinations.

Melanoma in-situ arising in seborrheic keratosis: a case report

BACKGROUND

Seborrheic keratosis is a very common benign skin tumor in man. Melanoma is rare but is the most dreaded of all malignant skin tumors. A melanoma arising in a seborrheic keratosis is distinctly rare. We are reporting such a case occurring in an 86-year-old man.

CASE PRESENTATION

An-86-year-old male with a history of multiple actinic keratoses and seborrheic keratoses of the head and trunk presented with a mid-back skin lesion. The lesion was poorly circumscribed, flat, and gray, with a pink-tan, well-circumscribed scaly nodule within it. The biopsied lesion was composed of the usual features of hyperkeratotic seborrheic keratosis, but with focal atypical melanocytic proliferation with nesting along the dermal-epidermal junction. We interpreted this lesion as a melanoma in-situ arising within a seborrheic keratosis.

CONCLUSION

It is not uncommon for many physicians to remove a typical seborrheic keratosis without a confirmatory microscopic confirmation. We urge that all such lesions be examined by the pathologist to avoid missing another concomitant malignant lesion such as melanoma which needs adequate resection and close follow-up.

Melanoma mimicking seborrheic keratosis: an error of perception precluding correct dermoscopic diagnosis

Seborrheic keratosis is a common skin lesion that can usually be recognized either clinically or dermoscopically. However, melanomas mimicking seborrheic keratoses, as well as melanomas arising in association with seborrheic keratoses, have been described. We report the case of a patient with a lesion that initially revealed "classic" dermoscopic features of a seborrheic keratosis. However, during follow-up, changes in color developed within the center of the lesion that led the clinician to the correct diagnosis of melanoma. Upon retrospective evaluation of the baseline image of the lesion; the clinician was now able to "see" that which his brain could not appreciate on initial examination and to realize that the lesion had subtle features suspect for melanoma. This case represents a diagnostic pitfall due to errors in perception. Dermatologists should be cognizant of "errors in perception"; we suggest that a final dermoscopic judgment of a seborrheic keratosis be rendered by combining the gestalt diagnosis of the overall pattern, with deliberate dermoscopic analysis of all quadrants of the lesion.