Quality assurance of radiation therapy after breast-conserving surgery among patients in the BOOG 2013-08 trial.

BACKGROUND AND PURPOSE: In the BOOG 2013-08 trial (NCT02271828), cT1-2N0 breast cancer patients were randomized between breast conserving surgery with or without sentinel lymph node biopsy (SLNB) followed by whole breast radiotherapy (WBRT). While awaiting primary endpoint results (axillary recurrence rate), this study aims to perform a quality assurance analysis on protocol adherence and (incidental) axillary radiation therapy (RT) dose. MATERIALS AND METHODS: Patients were enrolled between 2015 and 2022. Data on prescribed RT and (in 25% of included patients) planning target volumes (PTV) parameters were recorded for axillary levels I-IV and compared between treatment arms. Multivariable linear regression analysis was performed to determine prognostic variables for incidental axillary RT dose. RESULTS: 1,439/1,461 included patients (98.5%) were treated according to protocol and 87 patients (5.9%) received regional RT (SLNB 10.9%, no-SLNB 1.5 %). In 326 patients included in the subgroup analysis, the mean incidental PTV dose at axilla level I was 59.5% of the prescribed breast RT dose. In 5 patients (1.5%) the mean PTV dose at level I was ≥95% of the prescribed breast dose. No statistically or clinically significant differences regarding incidental axillary RT dose were found between treatment arms. Tumour bed boost (yes/no) was associated with a higher incidental mean dose in level I (R2 = 0.035, F(6, 263) = 1.532, p 0.168). CONCLUSION: The results indicate that RT-protocol adherence was high, and that incidental axillary RT dose was low in the BOOG 2013-08 trial. Potential differences between treatmentarms regarding the primary endpoint can thus not be attributed to different axillary radiation doses.

Clinically node negative breast cancer patients undergoing breast conserving therapy, sentinel lymph node procedure versus follow-up: a Dutch randomized controlled multicentre trial (BOOG 2013-08).

BACKGROUND: Studies showed that axillary lymph node dissection can be safely omitted in presence of positive sentinel lymph node(s) in breast cancer patients treated with breast conserving therapy. Since the outcome of the sentinel lymph node biopsy has no clinical consequence, the value of the procedure itself is being questioned. The aim of the BOOG 2013-08 trial is to investigate whether the sentinel lymph node biopsy can be safely omitted in clinically node negative breast cancer patients treated with breast conserving therapy. METHODS: The BOOG 2013-08 is a Dutch prospective non-inferiority randomized multicentre trial. Women with pathologically confirmed clinically node negative T1-2 invasive breast cancer undergoing breast conserving therapy will be randomized for sentinel lymph node biopsy versus no sentinel lymph node biopsy. Endpoints include regional recurrence after 5 (primary endpoint) and 10 years of follow-up, distant-disease free and overall survival, quality of life, morbidity and cost-effectiveness. Previous data indicate a 5-year regional recurrence free survival rate of 99% for the control arm and 96% for the study arm. In combination with a non-inferiority limit of 5% and probability of 0.8, this result in a sample size of 1.644 patients including a lost to follow-up rate of 10%. Primary and secondary endpoints will be reported after 5 and 10 years of follow-up. DISCUSSION: If the sentinel lymph node biopsy can be safely omitted in clinically node negative breast cancer patients undergoing breast conserving therapy, this study will cost-effectively lead to a decreased axillary morbidity rate and thereby improved quality of life with non-inferior regional control, distant-disease free survival and overall survival. TRIAL REGISTRATION: The BOOG 2013-08 study is registered in ClinicalTrials.gov since October 20, 2014, Identifier: NCT02271828. https://clinicaltrials.gov/ct2/show/NCT02271828.

The value of completion axillary treatment in sentinel node positive breast cancer patients undergoing a mastectomy: a Dutch randomized controlled multicentre trial (BOOG 2013-07).

BACKGROUND: Trials failed to demonstrate additional value of completion axillary lymph node dissection in case of limited sentinel lymph node metastases in breast cancer patients undergoing breast conserving therapy. It has been suggested that the low regional recurrence rates in these trials might partially be ascribed to accidental irradiation of part of the axilla by whole breast radiation therapy, which precludes extrapolation of results to mastectomy patients. The aim of the randomized controlled BOOG 2013-07 trial is therefore to investigate whether completion axillary treatment can be safely omitted in sentinel lymph node positive breast cancer patients treated with mastectomy. DESIGN: This study is designed as a non-inferiority randomized controlled multicentre trial. Women aged 18 years or older diagnosed with unilateral invasive clinically T1-2 N0 breast cancer who are treated with mastectomy, and who have a maximum of three axillary sentinel lymph nodes containing micro- and/or macrometastases, will be randomized for completion axillary treatment versus no completion axillary treatment. Completion axillary treatment can consist of completion axillary lymph node dissection or axillary radiation therapy. Primary endpoint is regional recurrence rate at 5 years. Based on a 5-year regional recurrence free survival rate of 98 % among controls and 96 % for study subjects, the sample size amounts 439 per arm (including 10 % lost to follow-up), to be able to reject the null hypothesis that the rate for study and control subjects is inferior by at least 5 % with a probability of 0.8. Results will be reported after 5 and 10 years of follow-up. DISCUSSION: We hypothesize that completion axillary treatment can be safely omitted in sentinel node positive breast cancer patients undergoing mastectomy. If confirmed, this study will significantly decrease the number of breast cancer patients receiving extensive treatment of the axilla, thereby diminishing the risk of morbidity and improving quality of life, while maintaining excellent regional control and without affecting survival. TRIAL REGISTRATION: The BOOG 2013-07 study is registered in the register of ClinicalTrials.gov since April 10, 2014, Identifier: NCT02112682 .

Inflammatory breast cancer: an overview.

Inflammatory breast cancer (IBC) is the most aggressive entity of breast cancer. Management involves coordination of multidisciplinary management and usually includes neoadjuvant chemotherapy, ablative surgery if a tumor-free resection margin is expected and locoregional radiotherapy. This multimodal therapeutic approach has significantly improved patient survival. However, the median overall survival among women with IBC is still poor. By elucidating the biologic characteristics of IBC, new treatment options may become available. We performed a comprehensive review of the English-language literature on IBC through computerized literature searches. The objective of the current review is to present an overview of the literature related to the biology, imaging and multidisciplinary treatment of inflammatory breast cancer.

[Mastitis as a symptom of malignancy]. / Mastitis als uiting van een maligniteit.

Several conditions can mimic the clinical presentation of inflammatory breast cancer. Three women presented with a swollen, red and painful breast which turned out to be inflammatory breast cancer after being treated as infectious mastitis. Non-puerperal bacterial mastitis may be confused with inflammatory breast cancer, leading to potentially preventable delays in diagnosis and treatment. The skin changes in inflammatory breast cancer are caused by tumour emboli within the dermal lymphatics, and not by infiltration of inflammatory cells as is suggested by the nomenclature. Patients who are treated for suspected mastitis without clinical improvement in one week should be referred to outpatient care in the surgery department to exclude underlying malignancy.

Value of fluorodeoxyglucose positron emission tomography in women with breast cancer.

BACKGROUND: The aim of this prospective study was to evaluate the role of fluorodeoxyglucose positron emission tomography (FDG-PET) in the staging of high-risk women with primary or recurrent breast cancer. METHODS: FDG-PET was performed in 42 women with a primary breast cancer and unfavourable characteristics, or who had a suspected relapse. FDG-PET and conventional staging methods were compared. In case of abnormality on FDG-PET, confirmation was always attempted. RESULTS: Increased uptake was found in five of 17 women with a primary cancer. In the 25 women with a suspected relapse, FDG-PET showed increased uptake in 43 areas, 22 correctly confirming the area of suspected relapse and 21 indicating other sites of metastases. Compared with conventional imaging, FDG-PET revealed additional (confirmed) lesions in two women with primary cancers and three with relapse. Patient management was changed for five women. CONCLUSION: FDG-PET is a sensitive diagnostic method for the detection of distant metastatic disease. Its exact role in women with breast cancer remains to be defined.

[The treatment of ductal carcinoma in situ (DCIS) of the breast]. / De behandeling van ductaal carcinoma in situ (DCIS) van de mamma.

Ductal carcinoma in situ (DCIS) of the breast is diagnosed more and more often in the Netherlands as a result of mammographic population screening and improved mammography techniques. Mastectomy and local excision, with or without radiotherapy, are used for the treatment of DCIS, but breast-conserving therapy seems a logical option in view of the favourable prognosis. Radiotherapy following total excision of DCIS reduces the local recurrence rate by half. Incomplete excision of DCIS is associated with a higher rate of local recurrence, which is invasive in about 50% of the cases and can therefore affect the prognosis adversely. There are conflicting opinions in the literature as to which patients with DCIS can be treated with breast-conserving therapy and whether local excision should be followed by radiotherapy, as is the case for breast-conserving treatment of invasive mammary carcinoma. The diagnosis and treatment of DCIS are therefore complex and require a multidisciplinary approach. Patients may be selected for breast-conserving therapy on the basis of diagnostic characteristics and risk factors.

Post-irradiation angiosarcoma of the greater omentum.

A case of angiosarcoma of the greater omentum is reported. This angiosarcoma developed 8 years after irradiation for cervical carcinoma and presented with an intra-abdominal hemorrhage. We describe her clinical course, treatment and follow-up. Although several other locations of irradiation-induced sarcomas have been published, this is the first report in literature of a postirradiation angiosarcoma in the greater omentum.