Large cystic lesion. Intrathoracic sample from lesion wall.
1. "Mediastinal tissue": A piece of soft red tissue 8x6x4mm. Bisected for frozen section. FS DIAGNOSIS: SCC. (AET) 2. "Mass wall": A sheet of firm tissue 50x40x5mm. The inner surface is covered by friable brown material. Representative sections for frozen section. FS DIAGNOSIS: SCC. (AET). P2. 3. "Cyst content": Multiple fragments of soft cream coloured material measuring in aggregate 30x30x25mm. P1. 4. "Mediastinal mass": The specimen comprised of a collapsed pale tan cyst 125x120x90mm. The external surface of the cyst is focally fibrotic. The cyst wall is focally calcified. The internal surface of the cyst contains friable pale tan material. P5. Digital photo taken. (MAS)
1. Vascular fibrous tissue containing focally keratinising well differentiated squamous cell carcinoma.
2. Vascular fibrous tissue containing focally keratinising well differentiated squamous cell carcinoma.
3. Acellular debris.
4. Focally calcified fibrous tissue containing multiple foci of squamous cell carcinoma. Lymphovascular is identified. No luminal lining epithelium is identified.
1. Mediastinal tissue: Well differentiated squamous cell carcinoma.
2. Mass wall: Well differentiated squamous cell carcinoma.
3. Cyst contents: Amorphous material.
4. Mediastinal mass: Well differentiated squamous cell carcinoma within calcified fibrous cyst wall. Lymphovascular invasion identified.
Calcified cancers of the mediastinum and lung are uncommon.
The majority of mediastinal masses that contain calcification are usually teratomata, calcifications in mediastinal metastases or following radiotherapy for lymphoma.
Calcification maybe seen in cystic thymic tumours and has been described in mediastinal hydatid although very rare.
When calcification occurs in lung malignancies it is rarely curvilinear , it more commonly presents as an amorphous mass within a cancer.
This SCC most likely had its origin with a thymic cyst or some other congenital cystic structure of the mediastinum