A case of verrucous carcinoma on the finger.

Sir,

Verrucous carcinoma (VC) is a rare well-differentiated squamous cell carcinoma composed of four subtypes according to the site of occurrence: oral type, anogenital type, plantar type, and other cutaneous sites.[1] The risk factors for VC include chronic inflammation or irritation, betel nut chewing, smoking, and human papillomavirus (HPV) infection.[2] Here, we report a case of VC on the finger.

A 78-year-old Chinese woman presented with a tumoral mass arising on the right middle finger for 10 years was admitted into our hospital. Ten years ago, her right middle finger was sticked with a fishbone. The wound was healed after 1 week. But 1 month later, a soybean-sized indolent nodule occurred on the wound of her right middle finger pulp, with clear border and projecting over the peripheral skin. The patient felt mild itching in the nodule. The lesions gradually changed into hypertrophy through constant scratching. Six months ago, the nodule enlarged quickly up to 1.0 cm × 1.5 cm, presenting as a cauliflower with mild abnormal odor, and apt to bleed after touching. From then on, she felt mild pain in the lesion when moving the finger. The patient was otherwise well without medication. There was no similar illness in his family.

Physical examination revealed a circumscribed, cauliflower-like tumor located on the right middle finger pulp. It was about 1.5 cm × 2 cm × 0.5 cm in size. And its surface was covered by crust, and hard on palpation [Figure 1]. There was no regional lymphadenopathy. The X-ray examination of the right middle finger, thorax CT scan, and abdomen ultrasonic examination were all normal. Under the local anesthesia, a biopsy was performed on the edge of the tumor. Histopathology showed the lesions are both exophytic, with papillomatosis and a covering of hyperkeratosis and parakeratosis, and endophytic growth pattern. The tumors are composed of well-differentiated squamous epithelial cells with minimal atypia. The diagnosis of VC was confirmed by histopathology.

Figure 1

A circumscribed, cauliflower-like tumor located on the right middle finger pulp. It was about 1.5 cm × 2 cm × 0.5 cm in size. And its surface was covered by a crust, and hard on palpation

Then, the patient was executed with tumor excision and dermatoplasty surgery; the excision was expanded 0.5 cm beyond the edge of the lesion, to the tendon in depth [Figure 2]. A full-thickness skin graft was made to cover the wound. The histopathology of excisional mass border confirmed the tumor was removed entirely. In situ hybridization indicated a negative HPV reaction. The operation was successful. She had no recurrence after 4 months of the surgery [Figure 3].

Figure 2

The excision was expanded 0.5 cm beyond the edge of the lesion, to the tendon in depth

Figure 3

A full-thickness skin graft was made to cover the wound. The patient had no recurrence after 4 months of the surgery

VC of numerous other sites such as the skin (epithelioma cuniculatum), areas of hydradenitis suppurativa, genital lichen sclerosus, endometrium, lichen simplex chronicus, and bladder have also been described. Although any cutaneous area of the body may be affected, 90% of the VC of the skin are found on the feet. For the hands, to our knowledge, only 16 cases of VC have been published so far.[3]

However, there was no evidence of HPV infection in our patient. She has been sticked with a fishbone for 10 years without history of arsenic exposure, radiation, or chronic tar application. There was no significant viral pathogenic role in association between the wound and subsequent VC development in our case. It is hypothesized that chronic irritation of burn cuits and altered mechanisms of skin repairation have produced carcinogenic substances.[4] And another theory is that chronic cutaneous inflammatory processes with oncogenic-like “overdrive” of growth factors constantly stimulating epithelial cells may lead to malignant transformation.[3] The continuous and repetitive trauma on inflamed tissues might have significantly contributed to the development of the neoplasia. So we suggested that the type of carcinoma might also be included in the group of VC arising within chronic cutaneous conditions.[5]

Treatment modalities for VC include surgical excision, cryosurgery, carbon dioxide laser, chemotherapy, intralesional or iontophoretic methods, photodynamics therapy, systemic retinoid therapy, and radiotherapy. As in our case, the surgery excision is the most reliable treatment method for VC.[23467] As VC rarely metastasize but grow locally invasive with a fair risk of local recurrence, local tumor control is the foremost goal of treatment. The treatment of choice is complete surgical excision.

To conclude that VC on the finger is rare, our patient had a successful outcome with local excision of the tumor. If unexpected tumoral mass occurs, timely biopsy study is necessary in order to find cancerization promptly.