Chemotherapy-induced neuronal maturation in sinonasal teratocarcinosarcoma--a unique observation

Abstract

Sinonasal teratocarcinosarcoma (SNTCS) is a rare and highly malignant tumour with combined features of a teratoma and carcinosarcoma. We report the first case of a SNTCS in 23 year old male treated with neo-adjuvant chemotherapy followed by cranio-facial resection. The resection specimen displayed cellular maturation in the neuroectodermal component. The patient presented with a short history of nasal obstruction, epistaxis and headache. On imaging, a bone destroying lesion of left paranasal sinuses and nasal cavity was identified. The diagnosis of SNTCS could be offered only on the third biopsy which showed heterogeneous admixture of primitive neuroectodermal, epithelial and mesenchymal elements. An adequate sampling with high index of suspicion is needed to catch hold this rare tumor. Tumor was excised after 4 cycles of neo-adjuvant chemotherapy. On microscopic examination, it showed similar epithelial and mesenchymal components as the pretreatment biopsies. However, the primitive neuroectodermal component displayed extensive neuronal maturation. The undifferentiated neuroectodermal cells were completely absent in the post chemotherapy specimen. This case throws light on the morphologic evidence of chemotherapy induced maturation in the neuroectodermal component within SNTCS, an event hitherto not reported in the literature in case of SNTCS.

Keywords: Neo-adjuvant chemotherapy; Neuronal maturation; Sinonasal tumours; Teratocarcinosarcoma.

Fig. 1

a A large enhancing mass in the nasoethmoidal region with erosion of cribriform plate and large intracranial extension in the anterior cranial fossa. (pre-chemotherapy MRI). b Decrease in the size of the mass as compared to the prechemotherapy MRI (Post-chemotherapy MRI)

Fig. 2

a Admixture of the primitive neuroectodermal & benign mesenchymal component, as seen in the biopsy (200× Hematoxylin & Eosin). b Epithelial component in the form of a dilated gland with transition into squamous epithelium surrounded by benign mesenchymal component (400× Hematoxylin & Eosin)

Fig. 3

a & b Various components of the tumour in the form of heterogeneous admixture of glandular structures, nodules of neural tissue with neurofibrillary matrix and fibroblastic stroma, as seen in the resection specimen. (A-100×, B-200× Hematoxylin & Eosin)

Fig. 4

a Ganglion-like neuronal cells embedded in abundant mature neurofibrillary matrix (Hematoxylin & Eosin 400×). b Synaptophysin reactivity in neurofibrillary matrix (400×)

Fig. 5

a NFP positivity in the nodules of immature neural tissue with neurofibrillary matrix. b Note the immuno-negativity in the mature epithelial component seen in the centre

Fig. 6

CK-7 immunoreactivity in the epithelial component (200×)