Answer :
CT scan shows a homogenous, patchily enhancing mass lesion in the right
hemithorax with rib destruction noted anteriorly. Differential diagnosis includes Ewing's
sarcoma, PNET (primitive neuroectodermal tumour - Askin's tumour), malignant lymphoma and
(less likely) rhabdomyosarcoma of the chest wall.
This patient was subjected to open chest biopsy; the specimen showed clusters of small
ovoid cells arranged in a rosette formation. Periodic acid-Schiff (PAS) was negative and
neuron specific enolase (NSE) was weakly positive. Final diagnosis was given as Askin's
tumour.
In 1979, Askin et al described a chest wall tumour occuring in children which they called
"the malignant small cell tumour of the thoraco-pulmonary region in childhood",
now also known as the Askin's tumour, which is a rare malignant small cell
neuroepithelioma arising from the soft tissues of the chest wall or lungs, and has also
been classified as a PNET. CT guided FNAC, electron microscopy, and immuno histochemical
examination helps to differentiate Askin's tumour from other chest wall masses. |
References :
Saifuddin A, RobertsonRJH, Smith SEW. The radiology of Askin's tumours.Clin Radiol 1991;
43: 19-23
Gonzalez-Crussi F, Wolfson SL, Misugi K, Nakajima T. Peripheral neuro-ectodermal tumour of
chest wall in childhood. Cancer 1984; 54: 2519-2527.
Contribution : Dr Amarnath Sortur, Dr Kiron Master,
Detroit, USA. |
