Table of Contents
Definition / general | Essential features | Sites | Diagrams / tables | Clinical features | Diagnosis | Radiology images | Prognostic factors | Case reports | Treatment | Gross description | Frozen section images | Microscopic (histologic) description | Microscopic (histologic) images | Cytology images | Positive stains | Negative stains | Molecular / cytogenetics description | Differential diagnosis | Board review style question #1 | Board review style answer #1Cite this page: Andeen NK, Tretiakova M. Papillary type 1. PathologyOutlines.com website. https://www.pathologyoutlines.com/topic/kidneytumormalignantrccpaptyp1.html. Accessed September 30th, 2023.
Definition / general
- Type 1 vs type 2 described in 1997 by Delahunt and Elbe (Mod Pathol 1997;10:537); type 1 is more common than type 2
Essential features
- Composed of small cuboidal cells with scant pale cytoplasm arranged on single layer of papillary cores, tubules and glomeruloid structures
- Often contains foamy macrophages and psammoma bodies
- CK7 diffusely positive (Am J Surg Pathol 2014;38:887)
- Gains in chromosomes 3, 7 and 17 ( > 80%)
- MET activating mutations or amplifications (N Engl J Med 2016;374:135)
Sites
- Kidney, renal cortex
- May be multifocal and bilateral
Clinical features
- Less locally advanced disease and lower rates of metastasis than type 2 pRCC (Am J Surg Pathol 2014;38:887)
Diagnosis
- In one series of papillary RCCs, ~25% had classical type 1 features, ~25% were type 2 and ~50% had some degree of overlapping features (Am J Surg Pathol 2014;38:887)
Radiology images
Prognostic factors
- Stage for stage, better prognosis and survival times than Type 2 pRCC (Am J Surg Pathol 2014;38:887)
Case reports
- 12 year old boy with a horseshoe kidney (Case Rep Pathol 2015;2015:841237)
- 63 year old Caucasian man with synchronous colorectal cancer and papillary RCC (Anticancer Res 2016;36:4821)
- 75 year old man with papillary RCC within a renal oncocytoma (J Clin Pathol 2007;60:426)
Treatment
- Resection
- Systemic therapy varies (J Natl Compr Canc Netw 2017;15:804)
- Receptor tyrosine kinase inhibitors including sunitinib and sorafenib
- Bevacizumab
- Nivolumab, cabozantinib and lenvatinib plus everolimus
- Temsirolimus
Gross description
- Often well circumscribed with thick capsule
- Friable with patchy appearance (yellow, grey, brown) and frequent hemorrhage
Microscopic (histologic) description
- Small cuboidal cells arranged on single layer on papillary cores (Am J Surg Pathol 2014;38:887)
- Cells are small with uniform, scant pale cytoplasm and round, hyperchromatic nuclei without nucleoli
- Papillary cores often contain foamy macrophages
- May have psammoma bodies
- Lower grade than type 2
- Grading: ISUP nucleolar grade
Microscopic (histologic) images
Positive stains
Negative stains
- CAIX, 34BE12, TFE3, GATA3, p63 (Am J Surg Pathol 2014;38:e35)
Molecular / cytogenetics description
- Type 1 pRCC has more consistent chromosomal aberrations than type 2, including:
- Gains in chromosomes 3, 7 and 17
- MET activating mutations or amplifications (Eur Urol 2017;S0302-2838:30467, N Engl J Med 2016;374:135)
Differential diagnosis
- Metanephric adenoma: WT1+ and CD57+, CK7-
- Type 2 pRCC: has more cytologic pleomorphism, more multilayering and cells are more eosinophilic; foamy macrophages and psammoma bodies are less common; type 2 pRCC also has patchy weak or negative CK7 and EMA and higher expression of Ki67 and p53 than type 1 pRCC (Am J Surg Pathol 2014;38:e35)
Board review style question #1
Compared to type 2 pRCC, type 1 pRCC generally:
- Has more aggressive clinical behavior
- Has more CK7 expression and MET activation
- Has more diverse chromosomal aberrations
- Has more nuclear pleomorphism
Board review style answer #1
B. Has more CK7 expression and MET activation
Comment Here
Reference: Type 1 (basophilic) papillary renal cell carcinoma (pRCC)
Comment Here
Reference: Type 1 (basophilic) papillary renal cell carcinoma (pRCC)