Langerhans cell sarcoma arising from Langerhans cell histiocytosis: a case report

Abstract

Langerhans cell sarcoma (LCS) is a neoplastic proliferation of Langerhans cells that have overtly malignant cytologic features. It is a very rare disease and theoretically, it can present de novo or progress from an antecedent Langerhans cell histiocytosis (LCH). However, to our knowledge, LCS arising from an antecedent LCH has not been reported on. We present here a case of LCS arising from a pulmonary LCH. A 34 yr-old man who was a smoker, had a fever and a chronic cough. Computed tomographic (CT) scan revealed multiple tiny nodules in both lungs. The thoracoscopic lung biopsy revealed LCH. The patient quit smoking, but he received no other specific treatment. One year later, the follow up chest CT scan showed a 4 cm-sized mass in the left lower lobe of the lung. A lobectomy was then performed. Microscopic examination of the mass revealed an infiltrative proliferation of large cells that had malignant cytologic features. Immunohistochemical stains showed a strong reactivity for S-100 and CD68, and a focal reactivity for CD1a. We think this is the first case of LCS arising from LCH.

Fig. 1

Langerhans cell histiocytosis. Many tumor cells show grooved nuclei. There is an infiltration of lymphocytes and eosinophils around the tumor cells (H-E stain, ×200).

Fig. 2

A CT scan shows multiple tiny nodules in both lungs and a lobulated mass in the left lower lobe.

Fig. 3

The tumor is poorly circumscribed and has a gray white cut surface.

Fig. 4

Langerhans cell sarcoma. The tumor cells are highly pleomorphic and many tumor cells have hyperchromatic nuclei. There are infiltrations of neutrophils and eosinphils around the tumor cells (H-E stain, ×200).

Fig. 5

Langerhans cell sarcoma. The tumor cells are strongly positive for S-100 protein (×200).

Fig. 6

Langerhans cell sarcoma. The tumor cells are positive for CD1a (×200).