# Papillary carcinomas of the breast (encapsulated, solid and invasive papillary)

Source: https://onco.cc/cancers/papillary-carcinoma-breast/  
OnCo record `papillary-carcinoma-breast` (Cancer). Data CC BY-NC 4.0, attribute "Data from OnCo (onco.cc)"; commercial use needs a licence.

## TL;DR

Papillary carcinomas are rare breast cancers, about one in a hundred, that grow as finger-like fronds on stalks, often inside a cyst, mostly in older women. The encapsulated and solid forms behave almost like non-invasive disease and have an excellent outlook; the truly invasive papillary form is treated like ordinary hormone-driven breast cancer.

## Summary

The 2019 WHO classification groups four entities under papillary neoplasms: encapsulated papillary carcinoma (a papillary carcinoma within a cystic space surrounded by a fibrous capsule, with no myoepithelial layer), solid papillary carcinoma (in situ and invasive forms, often with neuroendocrine differentiation), invasive papillary carcinoma, and the new tall cell carcinoma with reversed polarity (Tan 2020). Papillary carcinoma makes up 0.5 to 1 percent of breast cancer; in 302 cases, solid papillary carcinoma was more often accompanied by conventional invasive carcinoma than the intracystic form, and lesions lacking a myoepithelial layer are regarded as a special low-grade form of invasion whose behaviour is nonetheless indolent (Rakha 2011). Tall cell carcinoma with reversed polarity (solid papillary carcinoma with reverse polarity) has cuboid or tall cells with eosinophilic cytoplasm at the basal pole, grooved nuclei, Ki-67 under 5 percent in seven of nine cases, CK5/6 and calretinin expression, and a favourable prognosis (Modern Pathology 2018).

How it differs from its parent: papillary carcinomas are cancers of older women, hormone-receptor positive and HER2-negative in the encapsulated and solid forms, with an outlook close to that of ductal carcinoma in situ; the pathology question (in situ or invasive) decides the treatment more than the stage.

How common: 0.5 to 1 percent of breast cancer (Rakha 2011).

Treatment: encapsulated and solid papillary carcinoma without conventional invasion are managed like ductal carcinoma in situ with excision and consideration of radiotherapy and endocrine therapy; a conventional invasive component is staged and treated as HR-positive breast cancer on the parent page (Rakha 2011).

## Fields

- Kind: Cancer
- Last checked: 2026-09-24
- Also known as: Papillary carcinomas of the breast; Papillary carcinoma of the breast; Encapsulated papillary carcinoma; Intracystic papillary carcinoma; Solid papillary carcinoma; Invasive papillary carcinoma; Tall cell carcinoma with reversed polarity
- Tags: subtype-page; wave4; breast
- Group: breast
- Burden: Papillary carcinoma accounts for 0.5 to 1 percent of breast cancer; in a review of 302 papillary carcinomas from three institutions, 208 (84 percent) were intracystic (encapsulated), 30 (12 percent) solid papillary and 9 papillary ductal carcinoma in situ (Rakha 2011).
- Subtypes: Encapsulated (intracystic) papillary carcinoma, 84 percent of papillary carcinomas; Solid papillary carcinoma, in situ or invasive, often neuroendocrine; Invasive papillary carcinoma (luminal, HR-positive); Tall cell carcinoma with reversed polarity (IDH2-mutated, favourable)
- Biomarkers: Absence of a myoepithelial layer (encapsulated and solid forms); Oestrogen and progesterone receptor positive, HER2 negative; Ki-67 (low); Neuroendocrine markers in solid papillary carcinoma

## Sections of this record

The page is a hub with ten sections in reading order; large sections have their own page. The same plan as JSON: https://onco.cc/api/v1/cancers/papillary-carcinoma-breast/sections.json

- Overview (on the hub): The TL;DR, the family this cancer belongs to, the organ, who gets it and what the state of the art is. https://onco.cc/cancers/papillary-carcinoma-breast/#overview
- What it is (on the hub): Anatomy, the subtypes and how they differ, how it is staged, and where advanced disease spreads. https://onco.cc/cancers/papillary-carcinoma-breast/#what-it-is [4 subtypes]
- Finding it (on the hub): How it shows itself, how it is confirmed, what screening exists, and the biomarkers clinicians test for. https://onco.cc/cancers/papillary-carcinoma-breast/#finding-it [4 biomarkers]
- Treating it (on the hub): The standard of care by setting, the medicines, surgery and radiotherapy named in it, and the regimens behind them. https://onco.cc/cancers/papillary-carcinoma-breast/#treating-it [2 settings]
- Evidence (on the hub): Trials recruiting now, the landmark trials, the key papers and what they mean, the latest literature, and the milestones year by year. https://onco.cc/cancers/papillary-carcinoma-breast/#evidence
- The science (on the hub): The molecular landscape: the targets and how often each appears, the pathways, the mechanics stages and the preclinical models. https://onco.cc/cancers/papillary-carcinoma-breast/#science [1 target]
- Where you are (own page): Cases by country, the UK and NHS pathway and other country lenses, and the expert centres with trials on record. https://onco.cc/cancers/papillary-carcinoma-breast/where-you-are/
- Living with it (on the hub): The decisions you may face, the aids that walk through them, the warnings on record, the first sixty days and the questions to ask. https://onco.cc/cancers/papillary-carcinoma-breast/#living-with-it [9 questions, 3 red cards]
- What is coming (own page): Everything in development, the open problems and what is being done about them, the roadmaps, and what changed on this record. https://onco.cc/cancers/papillary-carcinoma-breast/coming/ [1 medicine]
- Data (own page): Every connected record, the notes, the JSON, Markdown and RDF twins, and where the record came from and when it was checked. https://onco.cc/cancers/papillary-carcinoma-breast/data/ [5 connected records]

## Standard of care

- Encapsulated or solid, no conventional invasion: Managed as ductal carcinoma in situ: excision, with radiotherapy and endocrine therapy considered. ([Ductal carcinoma in situ (DCIS)](https://onco.cc/cancers/ductal-carcinoma-in-situ/), [Tamoxifen](https://onco.cc/drugs/tamoxifen/))
- With conventional invasive carcinoma: Treated as HR-positive breast cancer. ([HR-positive / HER2-negative breast cancer](https://onco.cc/cancers/breast-hr-positive/), [Endocrine therapy (SERMs, AIs, SERDs)](https://onco.cc/technologies/endocrine-therapy/))

## Sources

- Wikipedia: https://en.wikipedia.org/wiki/Breast_cancer_classification
- Tan 2020, Histopathology: the 2019 WHO classification of tumours of the breast: https://doi.org/10.1111/his.14091
- Rakha 2011, Am J Surg Pathol: encapsulated papillary carcinoma of the breast, 302 papillary carcinomas: https://doi.org/10.1097/pas.0b013e31821b3f65
- Modern Pathology 2018: solid papillary carcinoma with reverse polarity, nine cases: https://doi.org/10.1038/s41379-018-0047-1

## Connected records

- cancers: [Breast cancer (all types)](https://onco.cc/cancers/breast-cancer/), [Ductal carcinoma in situ (DCIS)](https://onco.cc/cancers/ductal-carcinoma-in-situ/), [HR-positive / HER2-negative breast cancer](https://onco.cc/cancers/breast-hr-positive/), [Invasive micropapillary carcinoma of the breast](https://onco.cc/cancers/invasive-micropapillary-carcinoma-breast/), [Mucinous carcinoma of the breast](https://onco.cc/cancers/mucinous-carcinoma-breast/), [Neuroendocrine neoplasms of the breast](https://onco.cc/cancers/neuroendocrine-neoplasms-breast/)
- technologies: [Endocrine therapy (SERMs, AIs, SERDs)](https://onco.cc/technologies/endocrine-therapy/)
- drugs: [Tamoxifen](https://onco.cc/drugs/tamoxifen/)

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JSON: https://onco.cc/api/v1/entities/papillary-carcinoma-breast.json