Ulcerative cutaneous nodule as a presenting feature of recurrent thyroid carcinoma.

Sir,

Papillary thyroid carcinoma (PTC) is the most common thyroid malignancy. PTC is often multifocal and metastasizes to regional lymph nodes in about 40% of cases. Distant metastasis of PTC is rare and usually involves the lungs, liver, bones, and brain. Cutaneous metastases occur in 0.6-10.4% of all patients with cancer and represent 2% of all cutaneous malignant neoplasms.[1] Cutaneous metastasis from a thyroid carcinoma is rare and usually occurs in the setting of disseminated neoplastic disease.[23] Here, we have reported a known patient of PTC, who, on follow-up, presented with a bleeding ulcerative nodule in the neck; further evaluation confirmed it to be the first evidence of a recurrent disease.

A 71-year-old man with co-morbidities of hypertension and chronic renal failure underwent total thyroidectomy with bilateral central compartmental dissection and right functional neck dissection for papillary carcinoma thyroid. The final histopathology suggested a multifocal papillary carcinoma thyroid with extrathyroidal spread and metastasis to 11 out of the 21 dissected nodes. He was on regular follow-up on suppressive doses of thyroxin after remnant ablation with 50 millicurie of Iodine-131.

Twelve years later, he presented to us with a 3 × 2 cm, ulcerative cutaneous nodule in the right side of the anterior neck at 3-cm above the thyroidectomy scar [Figure 1]. The occasional history of oozing from the nodule prompted his visit to us. Evaluation with magnetic resonance imaging (MRI) scan revealed a well-defined heterogeneous mass measuring 2.8 × 1.7 × 2.7 cm in the anterior neck overlying the thyroid cartilage and the sternocleidomastoid muscle [Figure 2a and b]. The thyroid gland was not visualized and the underlying soft tissue was normal. A chest skiagram revealed multiple bilateral pulmonary nodules suggestive of pulmonary metastasis. Neither the nodule nor the pulmonary lesions were radio avid on diagnostic Iodine-131 scan. His serum thyroglobulin was mildly elevated at 10.7.

Figure 1

(a) Clinical photograph at presentation, (b) Intraoperative photograph following excision of the ulcerative cutaneous nodule

Figure 2

(a and b) MRI revealing a well-defined heterogeneous mass measuring 2.8 × 1.7 × 2.7 cm in the anterior neck overlying the thyroid cartilage and the sternocleidomastoid muscle

The patient was taken up for palliative excision of the nodule after a cytology proof of an adenocarcinoma, possibly from a thyroid primary. The resultant defect was closed with a local advancement flap. The final histopathology revealed a 2 × 2 × 2 cm tumor with features suggestive of metastatic papillary carcinoma thyroid with skin infiltration [Figure 3]. The patient continues to be on follow-up on thyroxin suppression after getting adequately palliated from his bleeding episodes for over a year at the time of writing this article [Figure 4a and b].

Figure 3

H and E, ×20 – Section shows fibrocollagenous tissue lined by stratified squamous epithelium with tumor tissue infiltrating the overlying epidermis. The cells are seen as papillary structures around delicate fibrovascular cores. The cells are cuboidal seen with scanty cytoplasm and pale staining nuclei with nuclear grooving

Figure 4

(a) Clinical photograph of the patient a year following palliative surgery, (b) a chest skiagram showing multiple bilateral pulmonary nodules suggestive of pulmonary metastasis

The scalp is the most frequent cutaneous site of metastasis from carcinoma thyroid. The other cutaneous sites involved with lesser frequency are the cheeks, shoulders, arms, abdomen, and thighs. Cutaneous metastases may either be the initial manifestation of thyroid carcinoma or can be the first evidence of recurrence of thyroid carcinoma. The skin metastasis of PTC is mostly associated with aggressive and disseminated disease and shows a poor outcome, especially when associated with BRAFV600E mutations.[345] A progressive loss of differentiation is usually found in these tumors, leading to a loss in their iodine-concentrating ability, thereby making them unresponsive to radioiodine therapy. In conclusion, metastatic recurrence should be considered in the differential diagnosis of a cutaneous nodule in a patient with a history of cancer, and palliative surgical excision is a worthwhile option even in the presence of disseminated disease.