Mucinous Tubular and Spindle Cell Carcinoma of the Kidney
Differential Diagnosis
- Collecting duct carcinoma
- Papillary renal cell carcinoma with spindle cell foci
- Metanephric Adenoma
- Sarcomatoid renal cell carcinoma
- Carcinoid
| Mucinous Tubular and Spindle Cell Carcinoma of the Kidney | Collecting Duct Carcinoma |
|---|---|
| Cytologically bland tubules | Cytologically highly atypical tubules |
| Mucinous stroma | Desmoplastic stroma |
| Circumscribed | Aggressively invasive |
| Mucinous Tubular and Spindle Cell Carcinoma of the Kidney | Papillary Renal Cell Carcinoma with Low Grade Spindle Cell Foci |
|---|---|
| Lacks areas of classic papillary carcinoma | Areas of classic papillary carcinoma usually present |
| Mucinous stroma present | Mucinous stroma generally absent |
| Lacks trisomy 7 and 17 | Trisomy 7 and/or 17 present |
- Mucinous tubular and spindle cell carcinoma may show morphologic and immunophenotypic overlap with papillary renal cell carcinoma (Paner 2006)
- Features that may be shared
- Papillary growth
- Mucin production
- Foam cells
- AMACR expression
- We diagnose borderline cases as papillary carcinoma
- Urologists are much more familiar with that diagnosis
- That diagnosis will probably elicit more extensive followup
- Genetic studies can separate the two but are rarely indicated
| Mucinous Tubular and Spindle Cell Carcinoma of the Kidney | Metanephric Adenoma |
|---|---|
| Mucinous stroma | Lacks mucinous stroma |
| CK7 pos | CK7 neg |
| Mucinous Tubular and Spindle Cell Carcinoma of the Kidney | Sarcomatoid Renal Cell Carcinoma |
|---|---|
| Lacks areas of classic renal cell carcinoma | Aresa of classic renal cell carcinoma usually present |
| Cytologically bland spindle cells | Cytologically atypical spindle cells |
| Mucinous Tubular and Spindle Cell Carcinoma of the Kidney | Renal Carcinoid |
|---|---|
| Mucinous stroma | Lacks mucinous stroma |
| Lacks neuroendocrine chromatin pattern | Stippled chromatin |
| Tubular and spindled growth patterns | Trabecular growth pattern |
