Transmigration or Epidermization of Lip: Does an Entity Exist?

Lips are a cosmetically very important part of the face and any abnormality involving lips is promptly noticed and they come to the physician for resolution. Lips surround the oral aperture. Anatomically lip extends from the base of nose superiorly to the central part of mentolabial sulcus inferiorly and oral commissures laterally. The surface of the lips has four zones: hairy skin, vermilion border, vermilion, and oral mucosa. The vermilion is colloquially called as red lips and mucosa as wet lips.[1]

One of the common cosmetic problems of lips is the presence of apparently normal skin on vermilion or red lips. These patients are diagnosed as transmigration or epidermization of lips as it is felt that normal skin has crossed the vermilion border. However, despite this entity is common in clinical practice, the etiology and treatment of this entity are not well understood and there is hardly any reported literature on this entity.[2]

We examined 15 patients with this complaint who reported to our outpatient department (OPD) in the last 6 months and performed the clinical, dermoscopic, and histopathological examination. Clinical examination in these patients revealed skin colored plaque of variable size adjacent to the vermilion border on either upper or lower lip [Figures 1 and 2]. Dermoscopy showed white to yellow discrete to coalescing ovoid structures with central opacity [Figures 3 and 4] Histopathology revealed stratified parakeratotic epidermis overlying normal sebaceous glands that lack hair follicle and ductal communication with the surface [Figure 5]. We diagnosed these patients as Fordyce spots and managed with ablative carbon dioxide laser in continuous wave mode.

Figure 1

Normal skin crossing the vermilion border and overlying lower vermilion

Figure 2

Normal skin crossing upper and lower vermilion border and present over both upper and lower vermilion

Figure 3

Polarised dermoscopy (Dermlite™ DL4 ×10) shows the presence of discrete white to yellow ovoid structures. There is absence of pseudo-reticular pigment network that is normally present on facial skin

Figure 4

Polarized dermoscopy (Dermlite™ DL4 ×10) shows the presence of discrete to confluent yellow ovoid structures

Figure 5

Histopathology showed the presence of normal sebaceous gland without hair follicle or ductal communication with the surface (H & E ×10)

Dermoscopy of Fordyce spots has been described as white to yellow discrete ovoid structures with linear and branching vessels.[3] We believe after our observation in these patients that this normal skin over vermilion, which is also called as epidermization or transmigration is closely set Fordyce spots and should be diagnosed and managed similarly.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.