Large superficial basal cell carcinoma arising from moxa cautery

ARTICLE

Auteur(s) : Seok-Kweon Yun¹, Seong-Min Kim¹, Jin Park¹, Jong-Sun Lee¹, Ji-Hyun Yi², Han-Uk Kim¹, Chull-Wan Ihm¹

¹Department of Dermatology, Chonbuk National University Medical School, Chonbuk National University Hospital, Jeonju, 561-712, South Korea
²Department of Dermatology, The Armed Forces Daegu Hospital, Daegu, Korea

The development of basal cell carcinoma (BCC) on a burn scar is rather rare. Moxa cautery is a technique used in the East whereby heat generated from the burning of a small bundle of moxa is applied to an acupuncture point on the skin. We report an interesting case of BCC on the lower part of the abdomen (hypogastric area) which developed on a burn scar secondary to repeated moxa cautery.

A 58-year-old Korean man presented with a 3-year-history of a dark reddish plaque on the lower part of the abdomen. The patient had applied moxa cautery to the same abdominal site repeatedly for relief of abdominal pain over the past 10 years. He reported occasional accidental burns from the cautery, that were not serious. Approximately 3 years previously, he had noticed the development of an asymptomatic dark reddish papule at the site of the moxa cautery on his abdomen. The lesion slowly enlarged in size; however, he denied receiving treatment for the lesion. Physical examination revealed a well-demarcated, 7.2 × 5.7 cm, dark-reddish, round plaque with some brown and black crusts and pigmentation on the lower part of the abdomen (figure 1A). The patient had no remarkable past or family history of skin cancer, excluding his moxa cautery history. Histopathological examination showed nests of basaloid cells arising from basal layers of the epidermis and extending into the dermis. There was peripheral palisading of the nuclei of the tumor cell nests and peritumoral lacunae between the tumor cells and stroma (figure 1B). Based on the histopathological findings, this case was diagnosed as superficial BCC. Because of the patient’s strong refusal of surgery, the tumor was treated with radiation therapy. A time-dose schedule of 3 Gy was given at 2-day intervals for a total accumulated dose of 51 Gy. The lesion responded to radiation therapy well and there was no evidence of recurrence 5 years later.

The most important risk factor regarding the development of BCC is chronic ultraviolet light exposure. Additional risk factors include genetic predisposition, ionizing radiation, exposure to arsenic, and trauma [1-3].

The exact mechanism of trauma in the development of BCC is not clear; however, many theories have been proposed regarding the pathogenesis of malignant degeneration. In 1960, Connolly [4] postulated that poor vascularity and elasticity in scar tissue may make the lesion more sensitive to ultraviolet light. Bostwick [5] suggested that scar tissue prevents a host antigen-antibody response against the tumor. Moxa cautery is a traditional eastern therapeutic technique that involves applying the heat generated from burning moxa to an acupuncture point on the skin. It has been used throughout living memory in Asia because it is believed to relieve pain, strengthen blood, stimulate the flow of energy, and maintain general health.

In our case, it is possible that the burn scar secondary to repeated moxa cautery resulted in the development of BCC in an area protected from sun exposure. The patient delayed visiting our clinic for 3 years because he regarded the skin malignancy as a burn scar from repeated moxa cautery. The size of the BCC had been gradually increasing and the tumor was treated with radiation therapy.

Although it is unusual for skin cancers to develop in burn scar tissue, it is widely known that malignant degeneration may occur in long-standing burn scars. Treves and Pack [6] estimated that almost 2% of burn scars undergo malignant degeneration. The most common histological type of skin cancer that develops in chronic wounds is squamous cell carcinoma, followed by basal cell carcinoma. Chronic non-healing burn scars should be biopsied to exclude cutaneous malignancy.

Acknowledgements

References

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