Table 2

Data fields for the iBRA-2 study

Field	Options (definitions)
Section 1: demographic data
Age	Age at diagnosis in years
Height	In metres
Weight	In kilograms
Body mass index	Actual BMI will be collected and categorised as—underweight (<18.5 kg/m²)/normal weight (18.5–24.9 kg/m²)/overweight (25–29.9 kg/m²)/obese (30–34.9 kg/m²)/severely obese (35–39.9 kg/m²) Morbid obesity (>40 kg/m²)
Smoking status	Current smoker/ex-smoker >6 weeks/non-smoker
Diabetic	Yes/no
Other comorbidities	Ischaemic heart disease (yes/no); current steroid therapy (yes/no); other immunosuppressive therapy (yes/no); connective tissue disease (yes/no); other comorbidity (yes/no) with details
Prior and neoadjuvant treatments
Previous radiotherapy to ipsilateral breast	Yes/no
Neoadjuvant chemotherapy within 4–6 weeks of surgery	Yes/no
Neoadjuvant endocrine therapy	Yes/no
Neoadjuvant radiotherapy	Yes/no
Previous surgery to ipsilateral breast	Wide-local excision (yes/no, if yes, date MM/YY); Therapeutic mammaplasty (yes/no, if yes, date MM/YY); Breast reduction (yes/no, if yes, date MM/YY); Breast augmentation (yes/no, if yes, date MM/YY); Other (yes/no, if yes, date MM/YY): State procedure
Previous surgery to ipsilateral axilla	Sentinel node biopsy with wide-local excision (yes/no, if yes, date MM/YY); Stand-alone sentinel node biopsy (yes/no, if yes, date MM/YY); Axillary sample (yes/no, if yes, date MM/YY); Axillary clearance (yes/no, if yes, date MM/YY)

Section 2: operative data
Date of mastectomy±reconstruction	Day/month/year
ASA grade	Normal healthy individual Mild systemic disease that does not limit activities Severe systemic disease that limits activities but is not incapacitating Incapacitating systemic disease which is constantly life-threatening
Antibiotic use	Prophylactic (<24 hours)/1–5 days/extended course (5+ days)/until drains removed/other
Type of skin prep used at the time of surgery	Iodine/Chlorhexidine/2% chlorprep/other
Procedure details collected for RIGHT and LEFT breasts separately
Procedure performed	None Mastectomy only Skin-sparing (nipple sacrificing) mastectomy and immediate breast reconstruction Nipple-sparing mastectomy and immediate breast reconstruction Skin reducing (Wise pattern) mastectomy and immediate breast reconstruction Wide-local excision Reduction/mastopexy Augmentation
If IBR, type of reconstruction performed	Implant-based/pedicled flap/free flap/other
If patient undergoing implant reconstruction
Implant reconstruction—planned procedure	One-stage reconstruction—insertion of permanent implant at initial surgery Two-stage reconstruction—insertion of a tissue expander to be followed by insertion of a definitive implant Immediate-delayed reconstruction—insertion of a temporary expander in patients for whom radiotherapy is anticipated with a plan to perform a definitive autologous (tissue-based) reconstruction after radiotherapy is complete
Mode of lower pole coverage	None/fascial or complete submuscular coverage/dermal sling/biological mesh (eg, Strattice)/synthetic mesh (eg, TiLOOP)/prepectoral implant with total ADM coverage, for example, BRAXON/prepectoral implant with dermal sling/ADM
Details of product for lower pole coverage	Stattice/SurgiMend/Native/BioDesign/Veritas/SERI/TiLOOP/TIGR/other
Prosthesis details	Fixed volume implant (size in ccs) Temporary expander (volume of saline inserted in ml) Combined implant, for example, Beckers (silicone component (g), size when fully expanded, volume of saline inserted in ml) Polyurethene implant (yes/no)
If patient undergoing flap-based reconstruction
Type of pedicled flap performed	Autologous LD flap (no implant)/LD with implant/Pedicled TRAM/other
If LD with implant, prosthesis details	Fixed volume implant (size in ccs) Temporary expander (volume of saline inserted in ml) Combined implant, for example, Beckers (silicone component (g), size when fully expanded, volume of saline inserted in ml) Polyurethene implant (yes/no)
Type of free flap performed	Free TRAM/DIEP/SIEA/SGAP/IGAP/TUG/other
Indication for surgery	Malignancy (invasive/DCIS)—first operation/malignancy (invasive/DCIS)—following failed BCS (WLE/TM)/risk reduction/symmetrisation
If failed BCS (positive margins) date of initial surgery	Day/month/year
Grade of primary operating surgeon	Consultant/SAS doctor/Senior trainee (ST8+ or OPF)/ST6-7/ST5 or below
Mastectomy weight	Grams
Axillary surgery	None/sentinel node biopsy/axillary sample/axillary clearance/previous axillary staging

Section 3: postoperative oncology and MDT outcomes Pathology details for RIGHT and LEFT breasts will be collected separately
For patients having neoadjuvant chemotherapy, complete pathological response?	Yes/no
Invasive status	Invasive/DCIS
Grade of invasive disease/DCIS	Low grade (DCIS) or well differentiated (invasive) Intermediate grade (DCIS) or moderately differentiated (invasive) High grade (DCIS) or poorly differentiated (invasive)
Histological type	Ductal/lobular/mixed/other
Number of tumours	Single tumour or multifocal/centric tumours
Size of invasive tumour	mm (largest if >1 ipsilateral tumour)
Total size of lesion including DCIS	In pathological specimen (mm) On pretreatment diagnostic imaging (if neoadjuvant therapy) (mm)
Receptor status	ER—positive/negative/not known HER-2—positive/negative/not known Ki67—high/low/not known
Lymphovascular invasion	Yes/no/not known
Lymph node involvement	Number of involved lymph nodes (macro-metastases only) Total number of lymph nodes in pathological specimen
Plan from the therapeutic (postoperative) MDT
Date of postoperative MDT	Day/month/year
Further oncological surgery required	No/completion axillary clearance/re-excision of margins/other
Surgery, planned before adjuvant therapy	Yes with date (day/month/year)
Treatments recommended
Chemotherapy	Recommended by MDT/not recommended by MDT/for discussion with patient/for Oncotype DX testing/chemotherapy already received
Biological therapy (eg, Herceptin)	Recommended by MDT/not recommended by MDT
Radiotherapy to chest wall	Recommended by MDT/not recommended by MDT/for discussion with patient/already received
If radiotherapy recommended	With boost (yes/no)/to supraclavicular fossa (yes/no)/to axilla (yes/no)
Endocrine therapy	Recommended by MDT/not recommended by MDT

Section 4: complication data Please record any complications that occur BEFORE the start of adjuvant therapy OR in the first 6 weeks following surgery in patients not requiring chemotherapy or radiotherapy
Postoperative complication experienced	Yes/no
If yes—details of surgical complications experienced (see table 3 for definitions)	Seroma/haematoma/infection/mastectomy skin flap necrosis/nipple necrosis/wound dehiscence/implant loss/donor site skin necrosis/impaired flap perfusion requiring return to theatre for exploration or revision of anastomosis (flap salvage)/flap necrosis/other complication
Inhospital complications, including systemic complications	Yes/no
If yes, complication(s) experienced (see table 3 for definitions)	Deep vein thrombosis/pulmonary embolism/myocardial infarction/lower respiratory tract infection/blood transfusion/ unplanned admission to intensive care/high-dependency unit/urinary tract infection/surgical complication/other complication
Readmission to hospital	Yes/no If yes—date of readmission (day/month/year); reason for readmission
Return to theatre/reoperation	Yes/no If yes—date of reoperation (day/month/year); reason for reoperation

Section 5: adjuvant therapy data This section documents the time from LAST CANCER surgery to FIRST ADJUVANT treatment, that is, first dose of chemotherapy or first fraction of radiotherapy
Date of last definitive cancer surgery	Day/month/year
Chemotherapy
Chemotherapy—if offered	Patient accepts/patient declines
Oncotype DX risk stratification	High risk/intermediate risk/low risk
Chemotherapy recommended based on Oncotype DX score	Yes/no
Actual chemotherapy start date	Day/month/year
Was planned treatment modified, delayed or omitted (not given) due to a postoperative complication?	Not affected/delayed/modified/omitted completely/details
Radiotherapy
Radiotherapy—if offered	Patient accepts/patient declines
Actual radiotherapy start date	Day/month/year
Was planned treatment modified, delayed or omitted (not given) due to a postoperative complication?	Not affected/delayed/modified/omitted completely/details
All adjuvant therapies
Did any factors impact on time to delivery of adjuvant therapy?	Yes/no/unsure
If yes, please tick any factors that apply	Postoperative complication (yes/no) Capacity issue—lack of medical oncology appointments (yes/no) Capacity issue—lack of clinical oncology (RT) appointments (yes/no) Capacity issue—lack of radiotherapy planning slots (yes/no) Capacity issue—lack of chemotherapy delivery slots (yes/no) Capacity issue—lack of radiotherapy delivery slots (yes/no) Waiting for staging CT scan or results (yes/no) Waiting for staging bone scan or results (yes/no) Waiting for staging PET scan or results (yes/no) Waiting for ECHO or results (yes/no) Awaiting Oncotype DX results (yes/no) Administrative delay—problems with booking appointments (yes/no) Patient choice (yes/no) Patient-related issue, for example, needing physiopreradiotherapy (yes/no) Other (yes/no)—If yes, please give details

ADM, acellular dermal matrix; ASA, American society of Anesthesiology; BCS, breast-conserving surgery; CT, computerised tomography scan; DCIS, ductal carcinoma in situ; DIEP, deep inferior epigastric perforator flap; ECHO, echocardiogram; ER, oestrogen receptor; HDU, high-dependency unit; IBR, immediate breast reconstruction; IGAP, inferior gluteal artery perforator flap; ITU, intensive therapy unit; LD, latissimus dorsi; MDT, multidisciplinary team; OPF, oncoplastic fellow; PET, positron emission tomography scan; RT, radiotherapy; SAS, Staff, Associate Specialist and Specialty Doctors; SGAP, superior gluteal artery perforator flap; SIEA, superficial inferior epigastric artery perforator flap; TM, therapeutic mammaplasty; TRAM, transverse rectus abdominus myocutaneous flap; TUG, transverse upper gracilis flap; WLE, wide-local excision.