Thyroid & parathyroid
Papillary thyroid carcinoma
Other subtypes
Encapsulated
Author: Shahid Islam, M.D., Ph.D.
Last author update: 1 March 2009
Last staff update: 28 August 2023
Copyright: 2003-2024, PathologyOutlines.com, Inc.
PubMed Search: encapsulated variant papillary carcinoma
Table of Contents
Definition / general | Prognostic factors | Case reports | Gross description | Gross images | Microscopic (histologic) description | Microscopic (histologic) images | Cytology description | Differential diagnosisCite this page: Islam S. Encapsulated. PathologyOutlines.com website. https://www.pathologyoutlines.com/topic/thyroidencapsulated.html. Accessed December 26th, 2024.
Definition / general
- Papillary carcinoma totally surrounded by a capsule
- 8 - 13% of papillary carcinomas
Prognostic factors
- Excellent prognosis (Eur J Surg 1996;162:177, Cancer 1984;54:90)
- May have nodal metastases, but only rarely angiolymphatic invasion or distant metastases
Case reports
- 22 year old woman with encapsulated macrofollicular variant (Indian J Pathol Microbiol 2006;49:24)
Gross description
- Thick capsule, resembles follicular adenoma
Gross images
AFIP images
Tumor surrounded by fibrous capsule
Microscopic (histologic) description
- Nuclear changes of papillary carcinoma and psammoma bodies
Microscopic (histologic) images
Contributed by Andrey Bychkov, M.D., Ph.D. and AFIP
Papillary carcinoma encapsulated variant
Transcapsular invasion
Thickened capsule is violated by tumor growth
Typical papillary appearance
Cytology description
- Scattered clusters of follicular cells with focal Hürthle cell changes and prominent nuclear pleomorphism, mixed with colloid and normal appearing follicular cells
- May not show classic papillary nuclear features (Acta Cytol 2002;46:555)
Differential diagnosis
- Hyperplastic nodule with central cystic degeneration: papillary formations face lumen of cystically dilated cavity, "hot" on scan, pale and vacuolated colloid, no papillary nuclear features, negative for high molecular weight keratin
