11.4 Phyllodes Tumors & Breast Angiosarcoma

CBCN Certified Breast Care Nurse Exam

Track your progress as you read

Finished sections get a check mark.

1 Introduction: The CBCN Exam

CBCN Exam Facts, 2026 Blueprint & Study Plan

2 Chapter 1: Breast Health, Examination & Benign Conditions (Care Continuum)

1.1 Breast Anatomy, Vascular Supply & Hormonal Physiology 1.2 Clinical Breast Examination & Breast Awareness Education 1.3 Benign Breast Conditions, Mastalgia & Fibrocystic Changes

3 Chapter 2: Screening, Breast Density & Special Populations (Care Continuum)

2.1 Screening Modalities, Breast Density & Pharmacologic Risk Reduction 2.2 Screening & Breast Health in Special Populations

4 Chapter 3: Cancer Risk Assessment & Genetics (Care Continuum)

3.1 Proliferative Lesions, Atypia & High-Risk Benign Pathology 3.2 Breast Cancer Risk Models (Gail, Tyrer-Cuzick, Claus, BRCAPRO) 3.3 Hereditary Cancer Syndromes & Genetic Evaluation

5 Chapter 4: Patient Navigation, Surveillance & Survivorship (Care Continuum)

4.1 Patient Navigation, Barriers to Care, Social Determinants & Interprofessional Collaboration 4.2 Survivorship Care Planning, Surveillance Intervals & Recurrence Monitoring 4.3 Secondary Prevention, Physical Activity, Nutrition & Wellness Guidance

6 Chapter 5: Carcinogenesis & Diagnostic Evaluation (Diagnosis and Staging)

5.1 Carcinogenesis: How Breast Cancer Develops and Spreads 5.2 Clinical Assessment, Diagnostic Imaging & BI-RADS Categorization 5.3 Breast Biopsy Modalities & Image-Guided Localization Techniques

7 Chapter 6: Pathology, Biomarkers & Genomic Testing (Diagnosis and Staging)

6.1 Histopathology: In Situ Carcinomas & Invasive Carcinoma Subtypes 6.2 Receptor Biomarkers (ER, PR, HER2, Ki-67) & Molecular Subtypes 6.3 Multigene Genomic Assays & Recurrence Risk Stratification

8 Chapter 7: Clinical & Pathologic Staging (Diagnosis and Staging)

7.1 AJCC TNM Staging System (Anatomic vs Prognostic Staging) 7.2 Staging Workup: When to Use MRI, CT, Bone Scan & PET

9 Chapter 8: Breast Surgery, Axillary Staging & Reconstruction (Treatment Modalities)

8.1 Breast-Conserving Surgery, Margin Standards & Mastectomy Techniques 8.2 Axillary Staging: Sentinel Lymph Node Biopsy vs. Axillary Dissection 8.3 Post-Mastectomy Reconstruction & Oncoplastic Surgery

10 Chapter 9: Radiation Therapy & Chemotherapy (Treatment Modalities)

9.1 Radiation Therapy: Whole Breast, Chest Wall, Regional Nodal & Partial Breast Irradiation 9.2 Neoadjuvant vs. Adjuvant Chemotherapy Principles & Standard Regimens

11 Chapter 10: Endocrine, HER2-Targeted & Novel Systemic Therapies (Treatment Modalities)

10.1 Endocrine Therapy: SERMs, Aromatase Inhibitors, Ovarian Suppression & SERDs 10.2 HER2-Targeted Monoclonal Antibodies, Antibody-Drug Conjugates & Kinase Inhibitors 10.3 CDK4/6 Inhibitors, PARP Inhibitors & Immune Checkpoint Blockade 10.4 Trop-2 Antibody-Drug Conjugates, PI3K/AKT/mTOR Inhibitors & New Oral SERDs

12 Chapter 11: Specific Conditions & Special Populations (Treatment Modalities)

11.1 Triple-Negative Breast Cancer: Treatment Considerations 11.2 HER2-Positive Breast Cancer: Treatment Considerations 11.3 Inflammatory Breast Cancer & Paget Disease of the Nipple 11.4 Phyllodes Tumors & Breast Angiosarcoma 11.5 Treatment Considerations for Special Populations

13 Chapter 12: Symptom Management & Supportive Care (Nursing Practice)

12.1 Acute Chemotherapy Toxicities, Supportive Regimens & Oncologic Emergencies 12.2 Lymphedema Pathophysiology, ISL Staging & Complete Decongestive Therapy (CDT) 12.3 Musculoskeletal Toxicities, Bone Health & Vasomotor/GSM Relief 12.4 Complementary & Integrative Modalities 12.5 Cancer Rehabilitation: Physical, Occupational & Pelvic Floor Therapy

14 Chapter 13: Oncologic Emergencies (Nursing Practice)

13.1 Oncologic Emergencies I: Spinal Cord Compression, Hypercalcemia, Tamponade & SVC Syndrome 13.2 Oncologic Emergencies II: Hypersensitivity & Anaphylaxis, Sepsis, Pleural Effusion & Thromboembolism

15 Chapter 14: Professional Practice, Clinical Trials & Self-Care (Nursing Practice)

14.1 Professional Practice: Guidelines, Ethics, Legislation, Outreach & Accreditation 14.2 Clinical Trials in Breast Oncology 14.3 Nurse Self-Care: Compassion Fatigue, Burnout, Moral Distress & Substance Use

16 Chapter 15: Psychosocial Dimensions of Care (Psychosocial Dimensions)

15.1 Psychosocial Distress, Coping, Grief & Palliative Care 15.2 Culture, Spirituality, Sexual & Gender Identity, Age & Healthcare Disparities 15.3 Family & Caregiver Dynamics 15.4 Altered Body Image 15.5 Reproductive & Sexual Health

11.4 Phyllodes Tumors & Breast Angiosarcoma

Key Takeaways Explain This Topic AI

Phyllodes tumors are fibroepithelial tumors that grow faster and larger than fibroadenomas, typically in women in their 40s, and are graded benign, borderline, or malignant.

Phyllodes tumors are treated with wide local excision aiming for margins of about 1 cm, and axillary staging is not recommended because nodal spread is rare.

Malignant phyllodes tumors spread through the blood, most often to the lungs and bone, rather than through lymph nodes.

Secondary breast angiosarcoma appears years after breast radiation as painless purple, bruise-like skin discoloration or nodules in the treated field and requires punch biopsy.

Breast angiosarcoma is treated with wide surgical resection to negative margins, often mastectomy with extensive skin removal, and carries a high local recurrence rate.

Last updated: September 2026

Phyllodes Tumors
What They Are

Phyllodes tumors are fibroepithelial neoplasms, like fibroadenomas, but with a hypercellular stroma that forms leaf-like (phyllodes) projections into cystic spaces. They make up less than 1% of breast tumors. Key contrasts with fibroadenoma:

Feature Fibroadenoma Phyllodes tumor
Typical age Teens to 30s 40s (median age older)
Growth Slow; often stable Rapid; often over 3 cm and can become very large
Stroma Normal cellularity Hypercellular, may show atypia and mitoses
Recurrence after excision Rare Common if margins are inadequate
Malignant potential Essentially none Borderline and malignant grades can metastasize

Clinically, a phyllodes tumor is a smooth, mobile, painless mass that may enlarge quickly; large tumors stretch the skin, cause visible veins, or ulcerate. Imaging often looks like a fibroadenoma, and core biopsy may not distinguish them . A "fibroadenoma" that grows rapidly or is larger than about 3 cm should be excised.

Grading

The WHO classifies phyllodes tumors as benign, borderline, or malignant based on stromal cellularity, nuclear atypia, mitotic activity, stromal overgrowth, and margin appearance (pushing or infiltrative). Most are benign.

Treatment

Wide local excision aiming for margins of about 1 cm is the standard. For benign tumors, narrower negative margins may be acceptable if re-excision would cause significant deformity. Mastectomy is needed only when negative margins cannot be achieved with acceptable cosmesis.

No axillary staging. Lymph node metastases occur in well under 1% of cases, so sentinel node biopsy and axillary dissection are not recommended.

Radiation may be considered after excision of malignant or borderline tumors, especially with close margins, to reduce local recurrence.

Chemotherapy is not standard; metastatic malignant phyllodes tumors are treated like soft tissue sarcomas.

Endocrine therapy has no role , even though the epithelial component may express hormone receptors.

Malignant phyllodes tumors spread hematogenously , most often to the lungs and bone . Local recurrence can occur even after benign tumors, so surveillance includes clinical examination and breast imaging every 6 to 12 months for several years. Very young patients or those with a family history of sarcoma may warrant consideration of Li-Fraumeni syndrome.

Breast Angiosarcoma
Two Forms

Angiosarcoma is a malignant tumor of endothelial (vascular) cells and makes up less than 1% of breast malignancies.

Primary angiosarcoma arises in the breast parenchyma of young women (often 20s to 40s) without prior radiation and presents as a deep mass, sometimes with bluish overlying skin.

Secondary (radiation-associated) angiosarcoma arises in the skin of the treated breast or chest wall a median of about 6 years after radiation, usually in older women treated with lumpectomy and radiation. It occurs in roughly 0.05% to 0.3% of irradiated patients, so it is rare but increasingly seen as more patients survive breast cancer.

Stewart-Treves syndrome is angiosarcoma arising in a chronically lymphedematous arm, classically after radical mastectomy.

The Easily Missed Presentation

Secondary angiosarcoma looks like a painless bruise , purple or red discoloration, violaceous papules or nodules, or skin thickening within the radiation field. It is often mistaken for radiation changes, a hematoma, or a benign vascular lesion, and delays are common. Any new purple or bruise-like lesion on a previously irradiated breast without trauma needs a punch biopsy . Pathology shows endothelial markers (CD31, ERG), and radiation-associated tumors typically show MYC amplification .

Treatment and Prognosis

Surgery: wide resection to negative margins, usually mastectomy with removal of all irradiated skin when feasible, sometimes requiring flap coverage. Lymph node dissection is not routine.

Radiation: hyperfractionated re-irradiation is used in some centers to reduce local recurrence.

Systemic therapy: taxanes (especially weekly paclitaxel) and anthracyclines are active for unresectable, recurrent, or metastatic disease.

Prognosis: local recurrence is frequent and survival is poor compared with breast carcinoma, particularly for secondary angiosarcoma.

Nursing Priorities

Teach survivors who had breast radiation to report any new purple, red, or bruise-like skin changes in the treated area, even many years later.

For phyllodes tumors, explain that no lymph node surgery is needed and why surveillance continues after a "benign" diagnosis.

Prepare patients with angiosarcoma for extensive surgery and possible reconstruction with flaps, and address the psychological weight of a second cancer caused by treatment of the first.

Imaging and Biopsy Clues

Phyllodes tumors on ultrasound tend to be large, lobulated, and heterogeneous, sometimes with internal cystic spaces or clefts. Core biopsy that shows increased stromal cellularity, stromal overgrowth, or mitoses should prompt excision rather than surveillance. A growing "fibroadenoma" is excised even when the core biopsy looked benign.

Angiosarcoma may look normal or show only skin thickening on mammography; MRI better defines extent. Because skin involvement can extend beyond what is visible, surgeons often remove wide areas of irradiated skin.

Comparing the Two Rare Tumors

Feature Phyllodes tumor Angiosarcoma
Cell of origin Breast stroma (fibroepithelial) Vascular endothelium
Typical patient Woman in her 40s Young woman (primary) or older survivor years after radiation (secondary)

Presentation Rapidly enlarging, mobile, painless mass Painless purple or bruise-like skin change or nodules (secondary); deep mass (primary)

Surgery Wide excision with about 1-cm margins; no axillary staging Wide resection, usually mastectomy with removal of irradiated skin

Spread Hematogenous (lungs, bone) for malignant tumors Local recurrence and hematogenous spread

Adjuvant options Radiation for selected malignant or borderline tumors Re-irradiation in some centers; taxanes or anthracyclines for advanced disease

Survivorship Teaching

Patients treated for either tumor need clear explanations of why their care differs from "usual" breast cancer: no endocrine therapy for phyllodes tumors, and no sentinel node biopsy for either. Regular clinical examinations and imaging continue because local recurrence is the main risk.