Dermoscopic Features of Cutaneous Endometriosis Arising in a Cesarean Scar: A Case Report

Cutaneous endometriosis is a rare medical condition characterized by the growth of an endometrial tissue on the skin outside of the uterus. Dermoscopic examination of cutaneous endometriosis can provide valuable information for its diagnosis. However, only a few reports on its dermoscopic features have been published, and most of these mainly pertain to cutaneous endometriosis in the umbilicus. Here, we report a case of cutaneous endometriosis arising in a caesarean scar, with unique and distinct dermoscopic features.

A 40-year-old female with Fitzpatrick skin type 3 presented to our clinic with a tumorous growth in a caesarean scar. The patient was healthy and had no history of previous dermatological conditions. The patient had undergone two caesarean sections with the most recent one 5 years ago and had experienced no postoperative complications. Two years after the last caesarean section, the patient noticed a small, painful tumorous growth on the right end of the scar that slowly grew to 4 cm in size. Macroscopically, the lesion was nodular with papillomatous growths on top ( Figure 1 ). Dermoscopic examination ( Figure 2 ) revealed structureless red papillomatous projections, as well as nonpapillomatous areas with red dotted vessels encompassed by a white halo in a reticular network-configuration. At higher magnifications, structureless red on the papillomatous projections was discerned to be composed of dotted vessels. In addition, few purple clods could be seen. Upon further questioning, the patient confirmed cyclical bleeding from the tumor that corresponded with her menstrual cycle. A punch biopsy confirmed the diagnosis of endometriosis in the luteal phase ( Figure 3 ). The patient was referred to a gynecological clinic and is now scheduled for surgery.

To our knowledge, only a few reports on the dermoscopic features of cutaneous endometriosis have been published ( Table 1 ), with most of these reports mainly pertaining to cutaneous endometriosis in the umbilicus. Only one article could be found discussing cutaneous endometriosis in caesarean scars, as in our report. In contrast to our dermoscopic findings, the only other cutaneous endometriosis in a caesarean scar described by Tognetti et al. had dermoscopic findings of pigmented arborizing lines and granular structures over a gray background [ 5 ]. It also had bright dots and targetoid brownish structures. None of these features could be seen in our patient's lesion. Also differing from our findings, Jaimie et al. described a lesion consisting of an area of homogeneous structureless reddish localized pigmentation, a brown amorphous area, and parts where the normal skin network was more evident [ 2 ]. These lesions were different from our patient's lesion both macroscopically and dermoscopically. Resembling the lesion of our patient, Costa et al. described a lesion with erythematous violaceous polypoid projections with light brown round spots and areas with bleeding in the follicular phase with an increased volume of erythematous-bluish in the luteal phase [ 3 ]. The violaceous parts described by Costa et al. are much more distinct in our case; however, upon closer inspection, they are better described as purple clods. Secondly, these purple clods are not limited to only polypoid projections in our case. Due to their color, we believe these clods to be of pools of deoxygenated blood. Additionally, no dotted vessels could be discerned in the case presented by Costa et al. Conversely, these dotted vessels were reported by De Giorgi et al. as homogeneous red pigmentation with embedded red globules, gradually fading toward the periphery [ 1 ], while Buljan et al. reported homogeneous dotted vessels over a red structureless area with brownish hue [ 4 ]. However, neither of these reports presented a distinctive case of dotted vessels encompassed by a white negative reticular network, as we do. Furthermore, Di Georgi et al.'s and Buljan et al.'s dermoscopic findings were of umbilical lesions as compared to our caesarian section. The primary strength of this case report is that it provides dermoscopic pictures with a detailed description of a condition scarcely described in the literature. This may also raise awareness of this rare condition. It is also distinctively different from the few previously published case reports. The main limitation of this case report is that it consists of a single case, which may limit the generalizability, as it is currently unknown what other appearances of cutaneous endometriosis can be assumed. Additional studies are needed to confirm our findings.

Our case report adds to the current limited knowledge of the dermatological features of cutaneous endometriosis. The distinctive dermoscopic features we described, primarily dotted vessels encompassed by a white reticular network, have not been previously reported. This report also raises awareness of the rarity of this condition. Additional case reports and studies are needed to better understand the appearance and characteristics of cutaneous endometriosis at various locations on the skin.