Postoperative radiotherapy in DBCG during 30 years. Techniques, indications and clinical radiobiological experience

Radiation dose to heart and cardiac substructures and risk of coronary artery disease in early breast cancer patients: A DBCG study based on modern radiation therapy techniques

BACKGROUND

Coronary artery disease (CAD) has been reported as a late effect following radiation therapy (RT) of early breast cancer (BC). This study aims to report individual RT doses to the heart and cardiac substructures in patients treated with CT-based RT and to investigate if a dose-response relationship between RT dose and CAD exists using modern radiation therapy techniques.

METHODS

Patients registered in the Danish Breast Cancer Group database from 2005 to 2016 with CT-based RT were eligible. Among 15,765 patients, the study included 204 with CAD after irradiation (cases) and 408 matched controls. Individual planning CTs were retrieved, the heart and cardiac substructures were delineated and dose-volume parameters were extracted.

RESULTS

The median follow-up time was 7.3 years (IQR: 4.6-10.0). Among cases, the median mean heart dose was 1.6 Gy (IQR 0.2-6.1) and 0.8 Gy (0.1-2.9) for left-sided and right-sided patients, respectively (p < 0.001). The highest RT doses were observed in the left ventricle and left anterior descending coronary artery for left-sided RT and in the right atrium and the right coronary artery after right-sided RT. The highest left-minus-right dose-difference was located in the distal part of the left anterior descending coronary artery where also the highest left-versus-right ratio of events was observed. However, no significant difference in the distribution of CAD was observed by laterality. Furthermore, no significant differences in the dose-volume parameters were observed for cases versus controls.

CONCLUSIONS

CAD tended to occur in the part of the heart with the highest left-minus- right dose difference, however, no significant risk of CAD was observed at 7 years' median follow-up.

Postmastectomy radiotherapy in high-risk breast cancer patients given adjuvant systemic therapy. A 30-year long-term report from the Danish breast cancer cooperative group DBCG 82bc trial

BACKGROUND

Between 1982 and 1990 the Danish Breast Cancer Cooperative Group (DBCG) conducted a randomized trial in high-risk pre- and postmenopausal (<70 years) breast cancer patients comparing mastectomy plus adjuvant systemic therapy alone versus the same treatment plus postoperative irradiation.

AIM

To present a comprehensive analysis of the complete DBCG 82bc study with a 30-year long-term follow-up of the cancer therapeutic effect and survival, together with an additional focus on the potential long-term life-threatening morbidity related to cardiac irradiation and/or the risk of secondary cancer induction.

METHODS

A total of 3083 patients with pathological stage II and stage III breast cancer were after mastectomy randomly assigned to receive adjuvant systemic therapy and postoperative irradiation to the chestwall and regional lymph nodes (1538 pts), or adjuvant systemic therapy alone (1545 pts). Pre- and menopausal patients (DBCG 82b) received 8-9 cycles of CMF with an interval of 4 weeks, whereas postmenopausal patients (DBCG 82c) received tamoxifen 30 mg daily for one year. The median follow-up time was 34 years. The primary endpoints were loco-regional recurrence (LRR) and overall mortality, and the secondary endpoints were distant metastasis, breast cancer mortality, and irradiation related late morbidity.

RESULTS

Overall the 30-year cumulative incidence of loco-regional recurrence was 9% in irradiated patients versus 37% in non-irradiated patients who received adjuvant systemic therapy alone (HR: 0.21 [95% cfl 0.18-0.26]). Distant metastasis probability at 30 years was 49% in irradiated patients compared to 60% in non-irradiated (HR: 0.77 [0.70-0.84]). Consequently, these figures resulted in a reduced breast cancer mortality: 56% vs 67% (HR: 0.75 [0.69-0.82], and overall mortality (81% vs 86% at 30 years (p < 0.0001), HR: 0.83 [0.77-0.90] in favor of irradiation. Radiotherapy did not result in any significant excess death of other courses, such as ischemic heart disease, HR: 0.82 [0.58-1.18]; nor secondary lung cancer HR: 1.44 [0.92-2.24], or other non-cancer related death HR: 1.15 [0.92-1.45].

CONCLUSION

The study definitely demonstrate that optimal long-term treatment benefit of high-risk breast cancer can only be achieved if both loco-regional and systemic tumor control are aimed for. Therefore, radiotherapy has an important role in the multidisciplinary treatment of breast cancer. The PMRT treatment did not result in excess ischemic heart damage, nor in other non-breast cancer related death.

Assessment of Radiation-Induced Malfunction in Cardiac Implantable Electronic Devices

Background

Radiation therapy (RT) is a standard cancer treatment modality, and an increasing number of patients with cardiac implantable electronic devices (CIEDs) are being referred for RT. The goals of this study were as follows: (i) to determine the incidence of CIED malfunction following RT; (ii) to characterize the various types of malfunctions that occur; and (iii) to identify risk factors associated with CIED malfunction following RT.

Methods

A retrospective study of patients with CIEDs who received RT between 2007 and 2018 at 4 Canadian centres (Sunnybrook Health Sciences Centre, Kingston General Hospital, Hamilton Health Sciences Centre, and University of Ottawa Heart Institute) was conducted. Patients underwent CIED interrogation after completion of RT, to assess for late damage to the CIEDs. Data on demographics, devices, and RT were compared for the primary outcome of device malfunction.

Results

Of 1041 patients with CIEDs who received RT, 811 patients with complete data were included. Device malfunctions occurred in 32 of 811 patients (4%). The most common device malfunctions were reduced ventricular/atrial sensing (in 13 of 32 [41%]), an increase in lead threshold (in 9 of 32 [22%]), lead noise (in 5 of 32 [16%]), and electrical reset (in 2 of 32 [6%]). Higher beam energy (≥ 10 MV) was associated with malfunction (P < 0.0001). Radiation dose was not significantly different between the malfunction and non-malfunction groups (58.3 cGy vs 65 cGy, respectively, P = 0.71).

Conclusions

Although RT-induced CIED malfunctions are rare (occurring in 4% of patients with a CIED who undergo RT), collaborative efforts between radiation oncologists and cardiac rhythm device clinics to optimize CIED monitoring are needed, to detect and manage CIED malfunctions. Malfunctions are more common in patients receiving higher–beam energy (≥10MV)RT.

Risk of coronary artery disease after adjuvant radiotherapy in 29,662 early breast cancer patients: A population-based Danish Breast Cancer Group study

PURPOSE

Radiotherapy (RT) for early breast cancer (BC) reduces the risk of recurrence and improves overall survival. However, thoracic RT may cause some incidental RT dose to the heart with subsequent risk of heart disease. During 2000-2010, CT-based RT planning was gradually introduced. The aim of this study was to investigate the risk of cardiac events in left-sided compared with right-sided BC patients treated during a non-CT-based (1999-2007) vs a CT-based period (2008-2016).

MATERIAL AND METHODS

Information on BC and cardiac events among Danish women was obtained from population-based medical registers. Patients diagnosed with BC during 1999-2016, were included. A cardiac event was defined as coronary artery disease or severe valvular heart disease.

RESULTS

Among 29,662 patients, 22,056 received RT. For those irradiated during the non-CT-based period, the 10-year cumulative risk of cardiac event was 1.7% (95% CI 1.4-2.0) at median follow-up of 11.1 years. The incidence rate ratio (IRR) for cardiac event in left-sided vs right-sided patients was 1.44 (1.07-1.94) and a trend towards worse outcome was seen within the first 10 years after RT and approached statistical significance with longer follow-up. Among patients irradiated during the CT-based period, the 10-year cumulative risk of cardiac event was 2.1% (1.8-2.4) at median 6.8 years follow-up. The IRR for cardiac event in left-sided vs right-sided patients was 0.90 (0.69-1.16) and no trend towards worse outcome within the first 10 years was observed.

CONCLUSION

This study confirmed a higher risk of cardiac events in left-sided vs right-sided BC patients irradiated during a non-CT-based period. For patients irradiated during a CT-based period, no increased risk of cardiac events in left-sided vs right-sided patients was observed within the first 10 years after RT, whilst information on cardiac events beyond 10 years after RT was limited.

Internal mammary lymph node metastases in breast cancer: what should radiologists know?

The internal mammary lymph node (IMLN) chain is a pathway through which breast lymphatic drainage flows. The internal mammary lymphatic vessel runs around the internal mammary artery and veins with IMLN in the parasternal intercostal spaces. IMLN metastasis, which forms a part of clinical TNM staging, may negatively affect the prognosis of primary breast cancer patients. IMLN metastasis is clinically detected using ultrasound, computed tomography, magnetic resonance imaging, and ¹⁸F-deoxyglucose positron emission tomography computed tomography. The uptake of radioactive tracers in IMLN with clinically negative axillary lymph nodes is often identified using sentinel lymph node mapping (SLNM) in primary breast cancer patients. The indication for IMLN biopsy or resection that is clinically detected or visualized using SLNM is controversial. The clinically suspicious IMLN may be considered for ultrasound-guided fine-needle aspiration. First IMLN recurrence needs to be biopsied. Irradiation of the breast, chest wall, and/or regional nodal irradiation, including IMLN, following lumpectomy or postmastectomy is recommended. Although radiation therapy for IMLN recurrence may improve clinical outcomes, it is also associated with pulmonary and cardiac toxicities. This review covers the local anatomy of IMLN, lymph drainage and image findings of IMLN with a discussion.

Impact of age, intrinsic subtype and local treatment on long-term local-regional recurrence and breast cancer mortality among low-risk breast cancer patients

AIM

To evaluate the long-term prognostic impact of age, local treatment and intrinsic subtypes on the risk of local-regional recurrence (LRR) and breast cancer mortality among low-risk patients.

MATERIAL AND METHODS

Cohort study with prospectively collected data, balanced five-year age groups, including 514 Danish lymph node negative breast cancer patients diagnosed between 1989 and 1998, treated with mastectomy (N = 320) or breast-conserving therapy (BCT) (N = 194) and without systemic treatment. Intrinsic subtype approximation was performed by combining information on estrogen-, progesterone-, HER2 receptor and Ki67.

RESULTS

The majority of the tumors had a luminal subtype: 70% Luminal-A (LumA), 16% Luminal-B (LumB), and 10% Luminal-HER2 + (Lum-HER2+). The distribution of intrinsic subtypes between younger (≤45 years) and older (>45 years) patients was similar. Intrinsic subtypes had no prognostic impact on the 20-year LRR risk, regardless of age. A distinct 20-year mortality pattern was observed among the younger patients: 11% of patients with LumB tumor died of breast cancer within the first five years after primary surgery, 23% of patients with Lum-HER2+ tumor died within a 5-10-year period, whereas patients with LumA tumor died with a constant low rate throughout the 20-year period. After 20 years of follow-up, patients with LumA tumor had breast cancer mortality comparable to that of patients with LumB tumor (20%) and lower than Lum-HER2+ tumor (39%). Among the older patients, no distinct mortality pattern was observed, and the 20-year breast cancer mortality was not associated with intrinsic subtypes.

CONCLUSION

Among low-risk patients, 96% of the tumors were Luminal and the distribution of intrinsic subtypes between younger (≤45 years) and older (>45 years) patients was similar. The observed higher frequency of LRR among younger low-risk BCT patients was not associated intrinsic subtype. The 20-year breast cancer mortality was non-significant for LumA tumors among the older patients, whereas among the younger patients, LumA tumors had a comparable mortality with LumB, but lower than for Lum-HER2 + tumors.

Danish Breast Cancer Cooperative Group

AIM OF DATABASE

Danish Breast Cancer Cooperative Group (DBCG), with an associated database, was introduced as a nationwide multidisciplinary group in 1977 with the ultimate aim to improve the prognosis in breast cancer. Since then, the database has registered women diagnosed with primary invasive nonmetastatic breast cancer. The data reported from the departments to the database included details of the characteristics of the primary tumor, of surgery, radiotherapy, and systemic therapies, and of follow-up reported on specific forms from the departments in question.

DESCRIPTIVE DATA

From 1977 through 2014, ~110,000 patients are registered in the nationwide, clinical database. The completeness has gradually improved to more than 95%. DBCG has continuously prepared evidence-based guidelines on diagnosis and treatment of breast cancer and conducted quality control studies to ascertain the degree of adherence to the guidelines in the different departments.

CONCLUSION

Utilizing data from the DBCG database, a long array of high-quality DBCG studies of various designs and scope, nationwide or in international collaboration, have contributed to the current updating of the guidelines, and have been an instrumental resource in the improvement of management and prognosis of breast cancer in Denmark. Thus, since the establishment of DBCG, the prognosis in breast cancer has continuously improved with a decrease in 5-year mortality from ~37% to 15%.

Failure pattern and survival after breast conserving therapy. Long-term results of the Danish Breast Cancer Group (DBCG) 89 TM cohort

Based on the results from the DBCG 82 trial, breast conserving therapy (BCT) has been implemented as standard in Denmark since 1989, and today constitutes more than 70% of the primary treatment. Our aim was to evaluate the implementation of BCT as a routine procedure in patients treated according to the DBCG 89 program and compare recurrence pattern and survival both overall and when separated in age groups, with the results from the randomized DBCG 82 TM trial.

MATERIAL AND METHODS

A total of 1847 patients treated between 1989 and 1999 were included in a retrospective population-based cohort study. Data from the DBCG database were completed via search through the Danish Pathology Data Bank and medical records.

RESULTS

Median follow-up time was 17 years. At 20 years the cumulative incidences of local recurrence (LR) and disease-specific mortality (DSM) were 15.3% and 25.8%, respectively. Twenty-year overall survival (OS) and recurrence-free survival were 63.7% and 43.1%, respectively. Subdivided by age groups cumulative incidences at 20 years were LR: 18.9%, 10.5% and 12.4%, and DSM: 28.9%, 18.9% and 28.4% in young (≤45 years), middle-aged (46-55 years) and older (≥56 years) women, respectively. In an adjusted analysis age maintained a significant and independent effect on both LR and DSM.

CONCLUSION

The DBCG 82 TM program was successfully implemented. The women treated with BCT in the DBCG 89 program displayed equal failure pattern and improved survival in comparison with women from the DBCG 82 TM protocol. Occurrence of first failure and mortality varied with age; demonstrated by increased risk of LR, DM and DSM in the young patients and increased risk of DM and DSM in the older patients, compared to the middle-aged patients.

Pattern of relapse after breast conserving therapy, a study of 1519 early breast cancer patients treated in the Central Region of Denmark 2000-2009

BACKGROUND

The continuous improvements in diagnosing and treatment of breast cancer are reflected in the ever changing pattern of recurrence. The aim of the study was to investigating recurrence pattern and prognostic factors of recurrence in a population-based cohort.

MATERIAL AND METHOD

In total 1519 consecutive patients treated with breast conserving therapy (BCT) for invasive carcinoma between 2000 and 2009 in the Central Region of Denmark was included. Patients received adjuvant irradiation and systemic treatment according to the guidelines of the Danish Breast Cancer Cooperative Group, including boost for young women and those with a narrow margin.

RESULTS

Median follow-up was 5.3 years (range 0.3-14.4). In total 183 women experienced breast cancer recurrence, 44 ipsilateral breast cancer recurrence, 13 regional recurrences, and 126 distant metastasis (DM). This corresponds to a cumulative risk of DM as first event at five and nine years of 6.5% and 12.6%, respectively. Further 42 women developed breast cancer in the contralateral breast. Disease-free survival (DFS) at five and nine years was 88% and 76%, respectively. Large tumor size (>20 mm), lymph node involvement, and vascular invasion were significantly associated with increased risk of DM. Margin width and age were not associated with risk of DM.

CONCLUSION

Acceptable recurrence rates and DFS were observed. Patients with large tumors, lymph node involvement, and vascular invasion had an increased risk of DM.

Uncertainties in estimating heart doses from 2D-tangential breast cancer radiotherapy

Background and purpose

We evaluated the accuracy of three methods of estimating radiation dose to the heart from two-dimensional tangential radiotherapy for breast cancer, as used in Denmark during 1982–2002.

Material and methods

Three tangential radiotherapy regimens were reconstructed using CT-based planning scans for 40 patients with left-sided and 10 with right-sided breast cancer. Setup errors and organ motion were simulated using estimated uncertainties. For left-sided patients, mean heart dose was related to maximum heart distance in the medial field.

Results

For left-sided breast cancer, mean heart dose estimated from individual CT-scans varied from <1 Gy to >8 Gy, and maximum dose from 5 to 50 Gy for all three regimens, so that estimates based only on regimen had substantial uncertainty. When maximum heart distance was taken into account, the uncertainty was reduced and was comparable to the uncertainty of estimates based on individual CT-scans. For right-sided breast cancer patients, mean heart dose based on individual CT-scans was always <1 Gy and maximum dose always <5 Gy for all three regimens.

Conclusions

The use of stored individual simulator films provides a method for estimating heart doses in left-tangential radiotherapy for breast cancer that is almost as accurate as estimates based on individual CT-scans.

DBCG-IMN: A Population-Based Cohort Study on the Effect of Internal Mammary Node Irradiation in Early Node-Positive Breast Cancer

PURPOSE

It is unknown whether irradiation of the internal mammary lymph nodes improves survival in patients with early-stage breast cancer. A possible survival benefit might be offset by radiation-induced heart disease. We assessed the effect of internal mammary node irradiation (IMNI) in patients with early-stage node-positive breast cancer.

PATIENTS AND METHODS

In this nationwide, prospective population-based cohort study, we included patients who underwent operation for unilateral early-stage node-positive breast cancer. Patients with right-sided disease were allocated to IMNI, whereas patients with left-sided disease were allocated to no IMNI because of the risk of radiation-induced heart disease. The primary end point was overall survival. Secondary end points were breast cancer mortality and distant recurrence. Analyses were by intention to treat.

RESULTS

A total of 3,089 patients were included. Of these, 1,492 patients were allocated to IMNI, whereas 1,597 patients were allocated to no IMNI. With a median of 8.9 years of follow-up time, the 8-year overall survival rates were 75.9% with IMNI versus 72.2% without IMNI. The adjusted hazard ratio (HR) for death was 0.82 (95% CI, 0.72 to 0.94; P = .005). Breast cancer mortality was 20.9% with IMNI versus 23.4% without IMNI (adjusted HR, 0.85; 95% CI, 0.73 to 0.98; P = .03). The risk of distant recurrence at 8 years was 27.4% with IMNI versus 29.7% without IMNI (adjusted HR, 0.89; 95% CI, 0.78 to 1.01; P = .07). The effect of IMNI was more pronounced in patients at high risk of internal mammary node metastasis. Equal numbers in each group died of ischemic heart disease.

CONCLUSION

In this naturally allocated, population-based cohort study, IMNI increased overall survival in patients with early-stage node-positive breast cancer.

Radiotherapy in patients with pacemakers and implantable cardioverter defibrillators: a literature review

An increasing number of patients with implantable cardiac rhythm devices undergo radiotherapy (RT) for cancer and are thereby exposed to the risk of device failure. Current safety recommendations seem to have limitations by not accounting for the risk of pacemakers and implantable cardioverter defibrillators malfunctioning at low radiation doses. Besides scant knowledge about optimal safety measures, only little is known about the exact prevalence of patients with devices undergoing RT. In this review, we provide a short overview of the principles of RT and present the current evidence on the predictors and mechanisms of device malfunctions during RT. We also summarize practical recommendations from recent publications and from the industry. Strongly associated with beam energy of photon RT, device malfunctions occur at ∼3% of RT courses, posing a substantial issue in clinical practice. Malfunctions described in the literature typically consist of transient software disturbances and only seldom manifest as a permanent damage of the device. Through close cooperation between cardiologists and oncologists, a tailored individualized approach might be necessary in this patient group in waiting time for updated international guidelines in the field.

Development and validation of a gene profile predicting benefit of postmastectomy radiotherapy in patients with high-risk breast cancer: a study of gene expression in the DBCG82bc cohort

PURPOSE

To identify genes predicting benefit of radiotherapy in patients with high-risk breast cancer treated with systemic therapy and randomized to receive or not receive postmastectomy radiotherapy (PMRT).

EXPERIMENTAL DESIGN

The study was based on the Danish Breast Cancer Cooperative Group (DBCG82bc) cohort. Gene-expression analysis was performed in a training set of frozen tumor tissue from 191 patients. Genes were identified through the Lasso method with the endpoint being locoregional recurrence (LRR). A weighted gene-expression index (DBCG-RT profile) was calculated and transferred to quantitative real-time PCR (qRT-PCR) in corresponding formalin-fixed, paraffin-embedded (FFPE) samples, before validation in FFPE from 112 additional patients.

RESULTS

Seven genes were identified, and the derived DBCG-RT profile divided the 191 patients into "high LRR risk" and "low LRR risk" groups. PMRT significantly reduced risk of LRR in "high LRR risk" patients, whereas "low LRR risk" patients showed no additional reduction in LRR rate. Technical transfer of the DBCG-RT profile to FFPE/qRT-PCR was successful, and the predictive impact was successfully validated in another 112 patients.

CONCLUSIONS

A DBCG-RT gene profile was identified and validated, identifying patients with very low risk of LRR and no benefit from PMRT. The profile may provide a method to individualize treatment with PMRT.

CT-planned internal mammary node radiotherapy in the DBCG-IMN study: benefit versus potentially harmful effects

BACKGROUND

The DBCG-IMN is a nationwide population-based cohort study on the effect of internal mammary node radiotherapy (IMN-RT) in patients with node positive early breast cancer. Due to the risk of RT-induced heart disease, only patients with right-sided breast cancer received IMN-RT, whereas patients with left-sided breast cancer did not. At seven-year median follow-up, a 3% gain in overall survival with IMN-RT has been reported. This study estimates IMN doses and doses to organs at risk (OAR) in patients from the DBCG-IMN. Numbers needed to harm (NNH) if patients with left-sided breast cancer had received IMN-RT are compared to the number needed to treat (NNT).

MATERIAL AND METHODS

Ten percent of CT-guided treatment plans from the DBCG-IMN patients were selected randomly. IMNs and OAR were contoured in 68 planning CT scans. Dose distributions were re-calculated. IMNs and OAR dose estimates were compared in right-sided versus left-sided breast cancer patients. In six left-sided patients, IMN-RT was simulated, and OAR doses were compared to those in the original plan. The NNH resulting from the change in mean heart dose (MHD) was calculated using a published model for risk of RT-related ischemic heart death.

RESULTS

In original plans, the absolute difference between right- and left-sided V90% to the IMNs was 38.0% [95% confidence interval (5.5%; 70.5%), p < 0.05]. Heart doses were higher in left-sided plans. With IMN-RT simulation without regard to OAR constraints, MHD increased 4.8 Gy (0.9 Gy; 8.7 Gy), p < 0.05. Resulting NNHs from ischemic heart death were consistently larger than the NNT with IMN-RT.

CONCLUSION

Refraining from IMN-RT on the left side may have spared some ischemic heart deaths. Assuming left-sided patients benefit as much from IMN-RT as right-sided patients, the benefits from IMN-RT outweigh the costs in terms of ischemic heart death.

Quality assurance of conventional non-CT-based internal mammary lymph node irradiation in a prospective Danish Breast Cancer Cooperative Group trial: the DBCG-IMN study

In 2003, the Danish Breast Cancer Cooperative Group (DBCG) initiated DBCG-IMN, a prospective study on the effect of adjuvant internal mammary lymph node radiotherapy (IMN-RT) in patients with early lymph node positive breast cancer (BC). In the study, standard DBCG IMN-RT was provided only to patients with right-sided BC. We provide estimates of doses to IMNs and organs at risk (OARs) in patients treated with the non-CT-based RT techniques used during the DBCG-IMN study.

MATERIAL AND METHODS

Five DBCG RT regimens were simulated on planning CT scans from 50 consecutively scanned BC patients, 10 in each group. Intended target volumes were chest wall or breast and regional lymph nodes ± IMNs. Field planning was conducted in the Eclipse(TM) RT treatment planning system. Subsequently, IMN clinical target volumes (CTVs) and OARs were delineated. Estimates on doses to the IMN-CTV and OARs were made.

RESULTS

IMN dose coverage estimates were consistently higher in right-sided techniques where IMN treatment was intended (p < 0.0001). Estimated doses to cardiac structures were low regardless of whether IMNs were treated or not. Post-lumpectomy patients had the highest estimated lung doses.

CONCLUSION

Overall, simulator-based treatment using the DBCG RT techniques resulted in satisfactory coverage of IMNs and acceptable levels of OAR irradiation.

Long-term evaluation of postmastectomy breast reconstruction with the pedicled transverse rectus abdominis musculocutaneous flap

The transverse rectus abdominis musculocutaneus (TRAM) flap is ideal for unilateral breast reconstruction. It can produce a breast with a lasting natural look, soft feeling, and good resemblance to the opposite breast. The aim was to evaluate long-term results of the TRAM flap reconstruction in an homogenous study population and to examine the impact on abdominal competence, appearance, and function relative to patient satisfaction. The study included 123 women from the cohort of patients undergoing a postmastectomy breast reconstruction in the period from 1992-2005. Data was collected from patient charts, a study-specific questionnaire, and a clinical follow-up visit. The response to the questionnaire was 81% (100/123), and 78 of them participated in a clinical follow-up visit. Eighty-four per cent were satisfied with the overall results of their breast reconstruction, and the majority of the women were pleased with the overall appearance of their abdomen. A significant correlation existed between satisfaction with the abdominal appearance and donor site complications (p = 0.01). No association was determined between complications in the breast area and smoking. A BMI above 25 increased the risk of complications. Radiation therapy (RT) significantly increased the risk of severe complications (p = 0.04) and of an inferior aesthetic result (p = 0.03). In conclusion, after a median of 6 years, women reconstructed with a TRAM flap were pleased with the overall result, with the appearance and strength of their abdomen including the umbilicus. Breast reconstruction with the pedicled TRAM flap results in lasting good results and pleased patients.

Delineation of target volumes and organs at risk in adjuvant radiotherapy of early breast cancer: national guidelines and contouring atlas by the Danish Breast Cancer Cooperative Group

During the past decade planning of adjuvant radiotherapy (RT) of early breast cancer has changed from two-dimensional (2D) to 3D conformal techniques. In the planning computerised tomography (CT) scan both the targets for RT and the organs at risk (OARs) are visualised, enabling an increased focus on target dose coverage and homogeneity with only minimal dose to the OARs. To ensure uniform RT in the national prospective trials of the Danish Breast Cancer Cooperative Group (DBCG), a national consensus for the delineation of clinical target volumes (CTVs) and OARs was required.

MATERIAL AND METHODS

A CT scan of a breast cancer patient after surgical breast conservation and axillary lymph node (LN) dissection was used for delineation. During multiple dummy-runs seven experienced radiation oncologists contoured all CTVs and OARs of interest in adjuvant breast RT. Two meetings were held in the DBCG Radiotherapy Committee to discuss the contouring and to approve a final consensus. The Dice similarity coefficient (DSC) was used to evaluate the delineation agreement before and after the consensus.

RESULTS

The consensus delineations of CTVs and OARs are available online and a table is presented with a contouring description of the individual volumes. The consensus provides recommendations for target delineation in a standard patient both in case of breast conservation or mastectomy. Before the consensus, the average value of the DSC was modest for most volumes, but high for the breast CTV and the heart. After the consensus, the DSC increased for all volumes.

CONCLUSION

The DBCG has provided the first national guidelines and a contouring atlas of CTVs and OARs definition for RT of early breast cancer. The DSC is a useful tool in quantifying the effect of the introduction of guidelines indicating improved inter-delineator agreement. This consensus will be used by the DBCG in our prospective trials.

Second primary cancers after adjuvant radiotherapy in early breast cancer patients: a national population based study under the Danish Breast Cancer Cooperative Group (DBCG)

BACKGROUND AND PURPOSE

To analyze the long-term risk of second primary solid non-breast cancer in a national population-based cohort of 46,176 patients treated for early breast cancer between 1982 and 2007.

PATIENTS AND METHODS

All patients studied were treated according to the national guidelines of the Danish Breast Cancer Cooperative Group. The risk of second primary cancers was estimated by Standardised incidence ratios (SIRs) and multivariate Cox regression models were used to estimate adjusted hazard ratios (HR) among irradiated women compared to non-irradiated. All irradiated patients were treated on linear accelerators. Second cancers were a priori categorized into two groups; radiotherapy-associated- (oesophagus, lung, heart/mediastinum, pleura, bones, and connective tissue) and non-radiotherapy-associated sites (all other cancers).

RESULTS

2358 second cancers had occurred during the follow-up. For the radiotherapy-associated sites the HR among irradiated women was 1.34 (95% CI 1.11-1.61) with significantly increased HRs for the time periods of 10-14 years (HR 1.55; 95% CI 1.08-2.24) and ≥ 15 years after treatment (HR 1.79; 95% CI 1.14-2.81). There was no increased risk for the non-radiotherapy-associated sites (HR 1.04; 95% CI 0.94-1.1). The estimated attributable risk related to radiotherapy for the radiotherapy-associated sites translates into one radiation-induced second cancer in every 200 women treated with radiotherapy.

CONCLUSIONS

Radiotherapy treated breast cancer patients have a small but significantly excess risk of second cancers.

Long-term follow-up of late morbidity, cosmetic outcome and body image after breast conserving therapy. A study from the Danish Breast Cancer Cooperative Group (DBCG)

The Danish Breast Cancer Cooperative Group (DBCG) introduced BCT as a standard treatment in Denmark in 1990. The aim of this study was to investigate late morbidity, cosmetic outcome, and body image after BCT and to associate these outcome variables with patient, tumor, and treatment characteristics.

MATERIAL AND METHODS

A total of 214 patients treated with BCT from 1989-2002 participated in a long-term follow-up visit comprising an interview, clinical examination, photos of the breast region and completion of a questionnaire on Body Image.

RESULTS

Median follow-up time was 12 years (range 7-20). Moderate to severe fibrosis was found in 23% of patients and was associated with chemotherapy [OR 2.6, CI (1.1; 5.9), p = 0.02], large breast size [OR 3.2, CI (1.6; 6.4), p = 0.001], and smoking [OR 2.4, CI (1.1; 4.9), p = 0.02]. Patients with a satisfactory cosmetic outcome, when assessed by a clinician, were characterized by small tumors [OR 3.2, CI (1.5; 6.8), p = 0.003] and small to medium sized breasts [OR 2.0, CI (1.1; 3.5), p = 0.002]. Fifty percent of patients scored good or excellent when assessed by a clinician compared to 88% when reported by the patients themselves. Patients satisfied with their own cosmetic outcome were the younger patients [< 50 years; OR 3.2, CI (1.1; 8.6), p = 0.03] with no postoperative complications [OR 3.3, CI (1.2; 9.2), p = 0.02]. Regarding body image 15% felt less feminine, 25% felt less sexually attractive, and 28% of patients had changed their clothing habits as a result of the disease or treatment.

CONCLUSION

The majority of patients were satisfied with their cosmetic outcome after BCT, whereas only half of the patients were found to have a good or excellent cosmetic outcome when assessed by the clinician. Body image was found to be only minimally disturbed in the majority of patients. The level of moderate to severe fibrosis was acceptable compared to both national and international studies with similar patient compositions.

Long-term evaluation of postmastectomy breast reconstruction

BACKGROUND

Reconstructing a breast mound constitutes the basis of breast reconstruction. The breast can be reconstructed using autologous tissue, implants or a combination thereof. The number of women wishing a breast reconstruction has increased, but evaluation of the results is lacking. The current study examined the long-term results from three methods of breast reconstruction to assess the subjective and the objective outcome.

PATIENTS AND METHODS

Patients undergoing first-time post mastectomy reconstruction, selected from the cohort of Danish women in the Central and North Region of Denmark, were evaluated. We included 363 women, reconstructed in 1990-2005. Data was collected from patient charts, a study specific questionnaire (to be found online at http://www.informahealthcare.com/doi/abs/10.3109/0284186X.2011.584554 ) and a clinical follow-up visit. The questionnaire included questions regarding demographic background and evaluation of the reconstructed breast and donor site. The clinical follow-up visit included an examination of the overall result and donor site.

RESULTS

The questionnaire was answered by 263 women, of whom 137 had an implant, 26 had a latissimus dorsi musculocutaneus flap and 100 had a pedicled transverse rectus abdominis musculocutaneus flap. Women reconstructed with autologous tissue were significantly more pleased with the result of the breast reconstruction than women reconstructed with an implant. After a median of seven years, neither the patient's age nor the length of time since the reconstruction significantly affected the patients' opinion of the overall result. There was no difference in the incidences of minor complications among the different reconstructive methods. BMI, smoking and radiation therapy influenced the risk of complications. Objective evaluation of the 180 women participating in the follow-up visit was in agreement with data from the questionnaire.

CONCLUSION

The type of reconstruction had a significant long-term influence on patient satisfaction and the objective result. Women reconstructed with autologous tissue were significantly more pleased, and the objective outcome was assessed as superior.

A nurse-led telephone session and quality of life after radiotherapy among women with breast cancer: a randomized trial

The purpose of this study was to investigate whether a nurse-led telephone session with patients suffering from breast cancer approximately ten days after final radiotherapy treatment affected their quality of life two to four weeks after radiotherapy. The study was conducted at the Radiotherapy ward at Vejle Hospital, Denmark between January and May 2010. The study population consisted of 100 patients, who were randomized with a 1:1 ratio to have either ordinary supportive conversations (control group), or ordinary supportive conversations and a supplementary nurse-led telephone session (intervention group). The quality of life was assessed using the questionnaires EORTC QLQ-C30 and EORTC QLQ-BR23. For statistical comparison of quality of life and for adjustment for covariates, multiple linear regression analysis was conducted. The mean [95 % CI] quality of life was 72.0 [66.4-77.6] in the control group and 69.9 [64.3-75.2] in the intervention group. Adjustment for covariates did not change the estimates. No statistically significant differences were found in the groups in either of the analyses. The nurse-led telephone session had no positive effect on the quality of life of patients with breast cancer two to four weeks after their final radiotherapy.

Cardiac dose estimates from Danish and Swedish breast cancer radiotherapy during 1977-2001

Background and purpose

To estimate target and cardiac doses from breast cancer radiotherapy in Denmark and in the Stockholm and Umeå areas of Sweden during 1977–2001.

Methods

Representative samples of irradiated women were identified from the databases of the Danish Breast Cancer Cooperative Group and the Swedish Nationwide Cancer Registry. Virtual simulation, computed tomography planning and manual planning were used to reconstruct radiotherapy regimens on a typical woman. Estimates of target dose and various measures of cardiac dose were derived from individual radiotherapy charts.

Results

Doses were estimated in 681 Danish and 130 Swedish women. Mean heart dose for individual women varied from 1.6 to 14.9 Gray in Denmark and from 1.2 to 22.1 Gray in Sweden. In Denmark, mean target doses averaged across women increased from 40.6 to 53.8 Gray during 1977–2001 but, despite this, mean heart dose averaged across women remained around 6 Gy for left-sided and 2–3 Gray for right-sided radiotherapy. In Sweden mean target dose averaged across women increased from 38.7 to 46.6 Gray during 1977–2001, while mean heart dose averaged across women decreased from 12.0 to 7.3 Gray for left-sided and from 3.6 to 3.2 Gray for right-sided radiotherapy. Temporal trends for mean biologically effective dose [BED] to the heart, mean dose to the left anterior descending coronary artery, the right coronary artery and the circumflex coronary artery were broadly similar.

Conclusions

Cardiac doses in Denmark were low relative to those in Sweden. In both countries, target dose increased during 1977–2001. Despite this, cardiac doses remained constant in Denmark and decreased in Sweden.

The clinical database and the treatment guidelines of the Danish Breast Cancer Cooperative Group (DBCG); its 30-years experience and future promise

Introduction. Since 30 years, DBCG (Danish Breast Cancer Cooperative Group) has maintained a clinical database allowing the conduct of quality control studies, of randomised trials, examination of the epidemiology of breast cancer and of prognostic and predictive factors. Material and methods. The original database included patients with invasive breast cancer, but has later been expanded to patients with in situ breast cancer and hereditary breast and ovarian cancer families. Results. The multidisciplinary cooperative group has provided successive treatment guidelines and 70% of the 77284 registered patients have been enrolled and received treatment according to these guidelines. The standard treatments and the randomised trials included in the DBCG programmes are all briefly described. Among high-risk patients 48% have participated in randomised trials, and the results of these trials have largely been implemented in the next generation of treatment guidelines. Records within the clinical database of archival tumour tissue have established a basis for translational research and epidemiologic research has been enabled through linkage to other healthcare registries. Discussion. The joint conception of the multidisciplinary breast cancer group and a clinical database has provided improvements in the management of breast cancer patients and has enabled recruitment of patients onto randomised trials.