Clinical findings are not helpful in detecting lentigo maligna melanoma in patients with biopsy‐proven lentigo maligna

Abstract

Background Lentigo maligna (LM) based on biopsy material might be lentigo maligna melanoma (LMM) after excision.Objectives Investigate whether clinical and dermoscopic mapping increases the detection rate of LMM when investigating staged excision specimens of biopsy proven LM.Methods Patients with biopsy-proven LM planned for staged excision were included. Using clinical inspection and dermoscopy, spots suspicious for LMM were marked. After the excision, needles were placed at the marked spots. Histological examination using vertical sections was done at the needles followed by the standard amount of vertical sections. ResultsIn 28 of the 58 biopsy-proven LM, there was clinical suspicion of LMM, only 3 of these 28 cases were upgraded into LMM. These three cases showed LMM in other sections, whereas only 1 case showed LMM around the needle. Within the group without clinical suspicion of LMM, 2 cases were LMM. Biopsy-proven LM were in fact LMM in 8.6% of the cases and were found without the clinical guidance of the dermatologist.Conclusions 8.6% of the biopsy-proven LM were LMM after complete histological examination. In this study, the dermatologist was not able to increase the detection rate of LMM by using clinical and dermoscopic mapping.

A risk‐scoring model for the differential diagnosis of lentigo maligna and other atypical pigmented facial lesions of the face: The facial iDScore

“…In particular, many SL were misdiagnosed as LM and PAK, while AN were interpreted as LM or SK. The differentiation between LM and LMM was difficult for all participants, 41% of LMM cases being misdiagnosed as LM and 12% of LM cases as LMM 25 …”

“…The differentiation between LM and LMM was difficult for all participants, 41% of LMM cases being misdiagnosed as LM and 12% of LM cases as LMM. 25 The proposed facial iDScore model allows rapid and easy calculation of the lesion partial score during a visit. It ranges from 0 to 16, without negative values or decimals, and is based on three items of objective data, four 'positive' dermoscopic features and two 'negative' dermoscopic features.…”

“…[12][13][14][15][16][17][18][19][20] However, several controversies have since arisen: (i) dermoscopic clues have been predominantly based on typical clear-cut lesions [18][19][20][21][22][23][24] ; (ii) there has been no firm consensus among researchers regarding the exact definitions and names for a variety of dermoscopic features observed in pigmented facial lesions, thus creating dozens of terms (nearly 50) and multiple describing the same feature (Table S1); (iii) in clinical practice, LM and LMM turn out to be very difficult to distinguish based on dermoscopic findings. 6,25,26 Finally, we know that some pigmented facial lesions of benign histopathology, especially those on photodamaged skin and/ or areas subject to repetitive microtrauma, may look clinically and dermoscopically atypical. 6,[12][13][14][15]27 In particular, we define as atypical pigmented facial lesions (aPFLs), all flat pigmented facial lesions displaying equivocal dermoscopic features, for which the dermatologist is uncertain about the diagnosis and needs a skin biopsy to rule out malignancy.…”

Intraoperative Immunohistochemistry During Mohs Micrographic Surgery and Staged Excision Decreases Local Recurrence Rates for Invasive Cutaneous Melanoma: A Systematic Review and Meta-Analysis

“…In all, 23 studies 28,29,32,33,35–38,44,52–55,63,64,68,69,71,72,76–79 used H&E staining alone encompassing 2,851 patients with 2,894 tumors with an average reported Breslow depth of 0.58 mm for invasive tumors; 17 studies 31,34,39–43,46,48–50,52,54,57,60,74,75 used IHC staining for all cases encompassing 3,835 patients with 3,907 tumors with an average reported Breslow depth of 0.84 mm for invasive tumors; 19 studies 6,9,27,30,45,47,51,56,58,59,61,62,65–67,70,73,80,81 included a mix of patients treated with either H&E alone or with IHC encompassing 5,357 patients with 5,789 tumors with an average reported Breslow depth of 1.0 mm for invasive tumors. Two studies included patient subsets treated with H&E alone and IHC alone, so the total sum of articles included in this meta analysis is 57.…”

Sentinel lymph node biopsy for lentigo maligna melanoma under local anaesthesia

“…Lentigo maligna melanoma (LMM) represents approximately 4%–15% of all melanomas. It occurs mainly in elderly patients and is most commonly located in the head and neck (H&N) region 1–3 . Therapy of LMM follows recent melanoma guidelines of the American Joint Cancer Committee (AJCC), 4 but due to its horizontal growth and location surgical therapy requirements and prognosis differ from those of other melanoma subtypes.…”