PT - JOURNAL ARTICLE AU - Niloofar Sina AU - Zaid Saeed-Kamil AU - Danny Ghazarian TI - Pitfalls in the diagnosis of lentigo maligna and lentigo maligna melanoma, facts and an opinion AID - 10.1136/jclinpath-2020-207051 DP - 2021 Jan 01 TA - Journal of Clinical Pathology PG - 7--9 VI - 74 IP - 1 4099 - http://jcp.bmj.com/content/74/1/7.short 4100 - http://jcp.bmj.com/content/74/1/7.full SO - J Clin Pathol2021 Jan 01; 74 AB - Lentigo maligna/lentigo maligna melanoma (LM/LMM) affects chronically sun-damaged skin of the head and neck with a slow radial growth phase. It is characterised by predominantly lentiginous proliferation of small, but atypical melanocytes with occasional upward scatter in an atrophic epidermis. It is not uncommon for pathologists to receive partial or scouting biopsies to assess for LM. This makes the interpretation of symmetry and circumscription of the lesions challenging. Therefore, both cytologic and architectural criteria should be taken into consideration to render an accurate diagnosis of melanoma. Moreover, pathologists should be vigilant to avoid missing invasion, as this can change the treatment plan and prognosis. Herein, we aim to discuss important pitfalls in the diagnosis of LMM and its invasive component. Some of these caveats are differentiating between true invasion versus adnexal involvement by the in situ component or an incidental intradermal nevus, detection of microinvasion and multifocal invasion, and recognition of desmoplastic/spindle cell melanoma component.