Make the Diagnosis

Make the Diagnosis - November 2015


Case and photo courtesy of: Andrew R. Styperek MD; Houston Methodist Hospital and DermSurgery Associates, Houston TX Arash Kimyai-Asadi MD; DermSurgery Associates, Houston TX Dr. Bilu Martin is in private practice at Premier Dermatology, MD in Aventura, Fla. To submit your case for possible publication, send an e-mail to dermnews@frontlinemedcom.com. A 65 year old Caucasian male arrived with a decades-long history of a lesion on his back measuring 25 x 21 centimeters. In the last few years he has noticed discharge and an unpleasant smell. He denied any fatigue, shortness of breath, lymph node enlargement, or any other systemic symptoms. He had a history of hyperlipidemia and hypertension, which were controlled with daily oral medications. The patient was not taking aspirin or any other anticoagulant therapy.

What’s your diagnosis?

Mycetoma

Keloidal Blastomycosis

Metastatic Breast Carcinoma

Basal Cell Carcinoma

DFSP

Diagnosis: Basal cell carcinoma

Basal cell carcinoma (BCC) is the most common skin cancer diagnosed in the United States, with approximately 2.8 million cases diagnosed annually, according to the Skin Cancer Foundation. While a minority of cases are linked to genetic syndromes (e.g., basal cell nevus syndrome), most cases result from ultraviolet sun exposure. A power law model was recently described linking ultraviolet exposure and incidence of basal cell carcinoma.

Many diagnosed BCC cases are small (< 1cm in size) and easily treated in the clinic. In cases where treatment is delayed for years due to financial, psychological, or psychiatric reasons, tumors can cause significant local tissue destruction and grow to alarming sizes.

The differential diagnosis of BCC may vary depending on the clinical sub-type (e.g., superficial, nodular, infiltrative, etc). Nodular BCC may mimic adnexal neoplasms, intradermal melanocytic nevi, Merkel cell carcinoma, or even amelanotic melanoma. Superficial BCC may mimic a lichenoid keratosis, Bowen’s disease, or other inflammatory conditions such as psoriasis and dermatitis. A larger lesion may mimic chronic infections such as mycetoma, or distant metastases from another primary carcinoma (breast or renal). Location and history can assist with teasing out the probable cause.

While diagnosis of this lesion can be made based on history and clinical appearance, this is best assisted with a biopsy, preferably a punch or incisional biopsy as chronic scarring and pseudoepitheliomatous hyperplasia may affect the pathologic diagnosis. Bacteria often colonize these large tumors and can lead to secondary infections. In this patient, maggots were noted in the skin.

While there are multiple modalities available for treating small tumors (e.g., topical imiquimod, 5-fluorouracil, electrodessication and curettage, excision, Mohs), larger tumors are often handled differently. While some might consider radiation therapy in this case, typically Mohs surgery is the treatment of choice. Oral vismodegib, a smoothened inhibitor, has been marketed for locally advanced basal cell carcinoma and has been used as a primary or adjunctive therapy with Mohs in tumors of this size. One important factor determining the choice of treatment is whether the primary tumor has spread. In tumors who have been left untreated for a long time, it is reasonable to image the patient to evaluate for metastases.

We present this case as an example where Mohs provided immediate definitive treatment. This tumor was cleared in 1 stage, with 67 slides read to evaluate the entire peripheral and deep margin. The Mohs surgery was performed under local anesthesia with no additional sedatives and 3-0 nylon sutures were used to approximate the wound. A two month follow-up photo is shown showing an almost healed surgical wound with an acceptable cosmetic result.

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