A 55-year-old female smoker was seen for 3 subcutaneous nodules that had appeared during the preceding month. The patient had a history of colon cancer (6 years earlier) but was cancer-free at the time of the consultation. Physical examination revealed 3 firm nodules of 1cm in diameter located beneath healthy-looking skin on the upper chest, rib cage, and armpit on the right side of the body (Fig. 1). Doppler ultrasound revealed 3 ovoid hypoechoic lesions in the subcutaneous tissue that lacked posterior reinforcement, exhibited internal vascularization, and were compatible with 2 subcutaneous metastases and 1 lymph node metastasis. After providing written informed consent, the patient underwent fine-needle aspiration (FNA) of the axillary adenopathy with a 21-G needle and core-needle biopsy (CNB) of the lesion on the upper chest with an 18-G needle. The procedures were performed under local anesthesia with ultrasound guidance in the operating room of the dermatology service on the same day as the consultation, with no complications. FNA cytology was positive for malignant cells (Fig. 2). Histology of the CNB was diagnostic of adenocarcinoma metastasis (Fig. 3) and the immunohistochemistry profile (CK7+, TTF-1+, CK20−, CDX2−) was compatible with a pulmonary origin. Computed tomography revealed findings compatible with lung cancer and the patient was referred to the oncology service for further studies and treatment.

Figure 1.

Lymph node metastasis in the right armpit.

(0.06MB).

Figure 2.

Malignant epithelial cells. Fine-needle aspiration smear (Giemsa staining).

(0.07MB).

Figure 3.

Metastatic adenocarcinoma of the lung. Core-needle biopsy obtained using an 18-G needle (hematoxylin-eosin staining).

(0.12MB).

In cases involving subcutaneous nodules with suspected malignancy the usual practice is to perform an incisional biopsy with a scalpel. Because our patient had 3 lesions, we opted to perform ultrasound-guided FNA and CNB in parallel in order to examine 2 lesions with minimal morbidity. FNA can be performed rapidly and causes minimal pain, and the corresponding pathology report can be rapidly obtained. In some cases, the small sample volume obtained by FNA can complicate the job of the pathologist and can give rise to false negatives. CNB is a better diagnostic technique than FNA as it yields one or more cylinders of histological tissue, from which multiple sections can be obtained and stained.1 Ultrasound-guided FNA and CNB are routinely performed by radiologists,2 but can also be performed by other well-trained ultrasound specialists (e.g. endocrinologists).3 Our dermatology service has had an ultrasound scanner available for consultations for the past 5 years, and we regularly carry out ultrasound-guided procedures. Consequently, our patient was able to benefit from these diagnostic techniques on the day of her consultation. In conclusion, this case illustrates the value of knowledge and experience in performing ultrasound-guided FNA and CNB, which can help dermatologists to rapidly diagnose subcutaneous metastases.