Oral melanoma and other pigmentations: when to biopsy?

Abstract

Oral pigmentations (OPs) are often neglected, although a meticulous examination of the oral cavity is important not only in the diagnosis of oral melanoma, but also for the detection of important clinical findings that may indicate the presence of a systemic disease. OPs may be classified into two major groups on the basis of their clinical appearance: focal and diffuse pigmentations, even though this distinction may not appear so limpid in some cases. The former include amalgam tattoo, melanocytic nevi, melanoacanthoma and melanosis, while the latter include physiological/racial pigmentations, smoker's melanosis, drug-induced hyperpigmentations, postinflammatory hyperpigmentations and OPs associated with systemic diseases. We will discuss the most frequent OPs and the differential diagnosis with oral mucosal melanoma (OMM), underlining the most frequent lesions that need to undergo a bioptic examination and lesions that could be proposed for a sequential follow-up.

Orale und Nagelpigmentierungen: eine für den Kliniker nützliche Parallelität

“…In der Mundhöhle ist das Zahnfleisch gleichmäßig betroffen, wobei die Ränder ausgespart bleiben (Abbildung 2c). Die OP entwickelt sich bereits in früher Kindheit und geht auf eine Erhöhung der Melaninproduktion zurück [1,15,18,19,21].…”

Oral and nail pigmentations: a useful parallelism for the clinician

“…Both OP and NP can manifest clinically with focal or diffuse involvement and are due to external or endogenous conditions . The most concerning differential diagnosis is melanoma.…”

“…The most concerning differential diagnosis is melanoma. Both nail and oral melanoma are uncommon: the former has a similar incidence in different racial groups, but accounts for 20 % of cases in dark phototypes and up to 2 % in fair phototypes, while the latter accounts for 7.5 % in Japanese people and < 1 % in Caucasians . Oral melanoma presents clinically as a black to grayish macule or nodule, sometimes with reddish areas or depigmentation.…”

“…Dermatoscopy is limited by the anatomical conformation of the mouth but may still represent a useful tool for early diagnosis, revealing a pseudonetwork, regression structures, blue veil and irregular/asymmetric colors and pigment . However, in 33–50 % of cases oral melanoma presents as an amelanotic lesion . The alveolar gingiva and hard palate are most commonly involved.…”

“…With both NP and OP, a prompt diagnosis may change the patient’s prognosis dramatically , so a biopsy is necessary in doubtful cases. Focal oral lesions > 0.5 cm in diameter should be biopsied if they appear in adults in the absence of known inducing factors or change with clinical/dermatoscopic monitoring.…”