Squamous Carcinoma of the Esophagus
Definition
- Malignant epithelial neoplasm of the esophagus demonstrating squamous differentiation
Alternate/historic names for spindle cell variant
- Carcinosarcoma
- Metaplastic carcinoma
- Polypoid carcinoma
- Pseudosarcomatous carcinoma
- Squamous cell carcinoma with spindled component
Diagnostic Criteria
- Most are conventional squamous carcinomas
- Defined based on cytologic atypia and invasion
- Small foci of glandular differentiation are permitted
- Lateral spread (intramucosal metastases) is common (11-16%)
- Second primary SCC is common (14-31%)
- 10% incidence of SCC at other sites also
- Variants (all are rare)
- Basaloid SCC
- Cohesive high grade poorly differentiated squamous carcinoma
- Usually has at least focal squamous differentiation
- High N/C ratio
- Scant amphophilic to basophilic cytoplasm
- High grade nuclei
- High mitotic rate, extensive apoptosis
- Coagulative necrosis common
- Well defined solid sheets, lobules and nests
- Frequent pseudoglandular and cribriform pattern
- No differentiated gland pattern
- Lacks the two cell type pattern of adenoid cystic carcinoma
- Alcian blue positive mesenchymal mucin in pseudoglandular spaces
- PAS/D+ hyaline basement membrane material may compress cells and cords
- Vascular invasion common, perineural invasion uncommon
- Most previously reported adenoid cystic carcinomas of the esophagus are probably basaloid squamous carcinomas
- Behavior not clearly different from SCC NOS
- Spindle cell squamous carcinoma
- SCC with a spindled/mesenchymal component
- SCC may be difficult to identify at edges of specimen or in situ
- Spindled/mesenchymal component highly variable
- May range from uniform and moderately atypical to resembling malignant fibrous histiocytoma
- May exhibit specific differentiation
- Osteosarcoma, chondrosarcoma, leiomyosarcoma, rhabdomyoblasts
- Epithelial markers detectable in about 50%
- High molecular weight keratin, p63 more sensitive
- Frequently polypoid (75%)
- 5 year survival not clearly different from SCC NOS
- Verrucous carcinoma
- Exophytic, warty surface
- Must have bland cytology and be well differentiated
- Invasion by smooth prongs of bland squamous cells
- Ragged infiltration not permitted
- Destroys adjacent tissues
- Typically very hard to diagnose histopathologically from biopsies
- Requires clinicopathologic correlation
- Metastases rare
- Adenosquamous
- Admixture of squamous and adenocarcinoma
- Mucoepidermoid
- Squamoid cells (rarely overtly keratinizing), mucin positive cells and intermediate cells
Robert V Rouse MD
Department of Pathology
Stanford University School of Medicine
Stanford CA 94305-5342
Original posting/updates: 11/29/09
