Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Idiopathic granulomatous mastitis (IGM) is a rare benign inflammatory breast condition with unknown cause, affecting approximately 2.4 per 100,000 women aged 20-40 years. Patients experience severe local symptoms including pain, redness, and recurrent abscesses that can last weeks to months and often mimic inflammatory breast cancer. Due to its rarity, mostly case reports and case series exist in the literature, leading to limited knowledge about risk factors, optimal treatment strategies, and clinical outcomes.
The GRAMAREG study is the first European registry for patients with histologically confirmed idiopathic granulomatous mastitis. This retrospective/prospective observational cohort study aims to systematically evaluate the incidence, diagnostic features, clinical course, treatment strategies, and patient outcomes of this uncommon disease. The study collects both retrospective data (from January 1, 2015 onwards) and prospective data from participating sites across Europe.
All diagnostic and therapeutic procedures are conducted according to institutional standards in clinical routine, as this is a non-interventional study. Patients in the prospective cohort are followed for up to 5 years to document symptom duration and recurrence rates.
Background:
Idiopathic granulomatous mastitis was first described by Kessler and Wolloch in 1972. The etiology remains largely unknown due to its rare occurrence. Valid prevalence data in Europe are lacking, though incidence appears higher in low-income countries compared to Western Europe. IGM predominantly occurs in women of childbearing age, mostly parous and more frequently of non-white ethnicity.
The diagnosis is confirmed only by histological evaluation, typically using core needle biopsy. Patients commonly develop recurrent breast abscesses that do not improve with antibacterial medication and often require repeat incisions or drainages. IGM must be differentiated from granulomatous inflammation associated with duct ectasia, foreign material reactions, specific infections (tuberculosis, fungi, parasites), systemic granulomatous diseases (sarcoidosis), and cystic neutrophilic granulomatous mastitis (CNGM) linked to Corynebacterium species.
Treatment strategies described in literature include high-dose steroids, immunosuppressive agents, bromocriptine, antibiotics, surgical resection, or even mastectomy. However, no evidence-based treatment recommendations are currently available.
Study Design:
This is an investigator-initiated non-interventional observational international prospective/retrospective cohort study with unlimited accrual and open registry duration due to disease rarity.
Data Collection Methods:
Retrospective Phase:
Collection and analysis via anonymized electronic database maintained by EUBREAST e.V. Participating Study Sites identify and document patients with histologically confirmed IGM treated between January 1, 2015, and Study Site activation. No patient identifying information is disclosed or documented. Data are fully anonymous without prospective follow-up.
Prospective Phase:
Patients with histologically confirmed IGM presenting after Study Site activation are informed about possible participation. Written informed consent is obtained. Diagnostic management and treatment follow institutional standards without protocol deviation. Follow-up occurs at 1, 3, and 5 years after first diagnosis to evaluate current symptoms and document potential recurrence.
Not provided
Not provided
Not provided
Not provided
| Label | Type | Description | Intervention Names |
|---|---|---|---|
| Idiopathic Granulomatous Mastitis Patients | Female and male patients ≥18 years old with histologically confirmed idiopathic granulomatous mastitis (IGM) or cystic neutrophilic granulomatous mastitis (CNGM) diagnosed after January 1, 2015. Histological confirmation obtained by minimally invasive biopsy or on surgical specimen by local pathology. Excludes patients with secondary granulomatous mastitis due to tuberculosis, sarcoidosis, fungal and parasitic infection, or foreign body. |
Not provided
| Measure | Description | Time Frame |
|---|---|---|
| Proportion of Patients Presenting with Specific Symptoms | Percentage of patients presenting with specific clinical symptoms including pain, redness, and palpable breast mass at initial presentation | At initial diagnosis (baseline) |
| Duration of Symptoms Depending on Treatment Strategy | Time from initial symptom onset to symptom resolution measured in weeks or months, stratified by treatment approach (systemic treatment, surgical intervention, conservative management) | From initial diagnosis through symptom resolution, up to 5 years |
| Measure | Description | Time Frame |
|---|---|---|
| Type and Duration of Systemic Treatment | Specific systemic treatments received (e.g., corticosteroids, immunosuppressive agents, antibiotics) and duration of each treatment in weeks or months | From initial diagnosis through completion of treatment, up to 5 years |
| Number of Surgeries Performed |
Not provided
Inclusion Criteria:
Exclusion Criteria:
Not provided
Not provided
Not provided
Patients diagnosed with histologically confirmed idiopathic granulomatous mastitis (IGM) or cystic neutrophilic granulomatous mastitis (CNGM) at participating European breast centers and hospitals. The population includes both retrospectively identified patients (diagnosed January 1, 2015, through Study Site activation) and prospectively enrolled patients (diagnosed after Study Site activation). IGM predominantly affects women of childbearing age, mostly parous, and more frequently of non-white ethnicity, though both males and females ≥18 years are eligible.
| Name | Role | Phone | Extension | |
|---|---|---|---|---|
| Natalia Krawczyk, PD Dr. med. | Contact | +49 0211 0 | Natalia.Krawczyk@med.uni-duesseldorf.de |
Not provided
| Facility | Status | City | State | ZIP | Country | Contacts |
|---|---|---|---|---|---|---|
| University Hospital Düsseldorf | Düsseldorf | North Rhine-Westphalia | 40225 | Germany |
Not provided
| Type | Includes Protocol | Includes SAP | Includes ICF | Document Label | Document Date | Document Uploaded Date | Document File Name |
|---|---|---|---|---|---|---|---|
| Prot | Yes | No | No | Study Protocol | Jul 1, 2025 | Jan 15, 2026 | Prot_000.pdf |
Not provided
| ID | Term |
|---|---|
| D058890 | Granulomatous Mastitis |
| D008413 | Mastitis |
| D003550 | Cystic Fibrosis |
| ID | Term |
|---|---|
| D011644 | Puerperal Disorders |
| D011248 | Pregnancy Complications |
| D005261 | Female Urogenital Diseases and Pregnancy Complications |
| D000091642 | Urogenital Diseases |
Not provided
Not provided
Not provided
Not provided
Not provided
Total number of surgical procedures (incision, drainage, excision, mastectomy) required per patient |
| From initial diagnosis through 5 years follow-up |
| Recurrence Rate | Proportion of patients experiencing recurrence of idiopathic granulomatous mastitis after initial treatment | At 1, 3, and 5 years after first diagnosis |
| Risk Factors Associated with Recurrence | Identification of patient demographics, clinical characteristics, and treatment factors associated with disease recurrence | At 1, 3, and 5 years follow-up |
| Time to Histological Confirmation | Time interval in days or weeks between first symptom occurrence and first histological confirmation of idiopathic granulomatous mastitis | At baseline (from retrospective chart review or patient recall) |
| Presentation on Breast Imaging | Imaging characteristics on mammography, sonography, and MRI (if performed) as assessed by the International Steering Committee | At initial diagnosis |
| Department of Gynecology and Obstetrics University Hospital Schleswig-Holstein | Lübeck | Schleswig-Holstein | 23562 | Germany |
|
| D001941 | Breast Diseases |
| D012871 | Skin Diseases |
| D017437 | Skin and Connective Tissue Diseases |
| D010182 | Pancreatic Diseases |
| D004066 | Digestive System Diseases |
| D008171 | Lung Diseases |
| D012140 | Respiratory Tract Diseases |
| D030342 | Genetic Diseases, Inborn |
| D009358 | Congenital, Hereditary, and Neonatal Diseases and Abnormalities |
| D007232 | Infant, Newborn, Diseases |