University of Groningen. Local treatment in young breast cancer patients Joppe, Enje

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University of Groningen Local treatment in young breast cancer patients Joppe, Enje IMPORTANT NOTE: You are advised to consult the publisher's version (publisher's PDF) if you wish to cite from it. Please check the document version below. Document Version Publisher's PDF, also known as Version of record Publication date: 2015 Link to publication in University of Groningen/UMCG research database Citation for published version (APA): Joppe, E. J. (2015). Local treatment in young breast cancer patients: Recurrence, toxicity and quality of life [Groningen]: University of Groningen Copyright Other than for strictly personal use, it is not permitted to download or to forward/distribute the text or part of it without the consent of the author(s) and/or copyright holder(s), unless the work is under an open content license (like Creative Commons). Take-down policy If you believe that this document breaches copyright please contact us providing details, and we will remove access to the work immediately and investigate your claim. Downloaded from the University of Groningen/UMCG research database (Pure): http://www.rug.nl/research/portal. For technical reasons the number of authors shown on this cover page is limited to 10 maximum. Download date: 06-12-2017

Chapter 4 56 ing system for the adverse effects of cancer treatment. Semin Radiat Oncol 2003;13:176-81. 12. Joiner MC, van der Kogel AJ. The linear-quadratic approach to fractionation and calculation of isoeffect relationships. In: Steel CG, editor. Basic clinical radiobiology. London: Arnold; 1997. p. 106-22. 13. Bartelink H, Horiot JC, Poortmans P, et al. Recurrence rates after treatment of breast cancer with standard radiotherapy with or without additional radiation. N Engl J Med 2001;345:1378-87. 14. McDonald MW, Godette KD, Whitaker DJ, Davis LW, Johnstone PA. Three-year outcomes of breast intensity-modulated radiation therapy with simultaneous integrated boost. Int J Radiat Oncol Biol Phys 2010;77:523-30. 15. Raiyawa T, Lertbutsayanukul C, Rojpornpradit P. Late effects and cosmetic results of simultaneous integrated boost versus sequential boost after conventional irradiation in breast-conserving therapy; out come of 7 months follow-up. J Med Assoc Thai 2009;92:390-7. 16. Bollet MA, Sigal-Zafrani B, Mazeau V, et al. Age remains the first prognostic factor for loco-regional breast cancer recurrence in young (<40 years) women treated with breast conserving surgery first. Radiother Oncol 2007;82:272-80. 17. Early Breast Cancer Trialists Collaborative Group (EBCTCG). Effects of chemotherapy and hormonal therapy for early breast cancer on recurrence and 15-year survival: an overview of the randomised trials. Lancet 2005;365:1687-717. 18. Livi L, Paiar F, Saieva C, et al. Survival and breast relapse in 3834 patients with T1- T2 breast cancer after conserving surgery and adjuvant treatment. Radiother Oncol 2007;82:287-93. 19. Bauer KR, Brown M, Cress RD, Parise CA, Caggiano V. Descriptive analysis of estrogen receptor (ER)-negative, progesterone receptor (PR)-negative, and HER2-negative invasive breast cancer, the so-called triple-negative phenotype: a population-based study from the California cancer Registry. Cancer 2007;109:1721-8. 20. Nguyen PL, Taghian AG, Katz MS, et al. Breast cancer subtype approximated by estrogen receptor, progesterone receptor, and HER-2 is associated with local and distant recurrence after breast-conserving therapy. J Clin Oncol 2008;26:2373-8. 21. Andreu FJ. Histologic diagnosis in young women with breast cancer. Breast Cancer Res Treat 2010;123:15-8. 22. Kwon JH, Kim YJ, Lee KW, et al. Triple negativity, young age as prognostic factors in lymph node-negative invasive ductal carcinoma of 1 cm or less. BMC Cancer 2010;10:557. 23. Smith TE, Lee D, Turner BC, Carter D, Haffty BG. True recurrence vs. new primary ipsilateral breast tumor relapse: an analysis of clinical and pathologic differences and their implications in natural history, prognoses, and therapeutic management. Int J Radiat Oncol Biol Phys 2000;48:1281-9. 24. Hurkmans CW, Cho BC, Damen E, Zijp L, Mijnheer BJ. Reduction of cardiac and lung complication probabilities after breast irradiation using conformal radiotherapy with or without intensity modulation. Radiother Oncol 2002;62:163-71. 25. Hurkmans CW, Meijer GJ, Vliet-Vroegindeweij C, van der Sangen MJ, Cassee J. High-- dose simultaneously integrated breast boost using intensity-modulated radiotherapy and inverse optimization. Int J Radiat Oncol Biol Phys 2006;66:923-30. 26. van der Laan HP, Dolsma WV, Schilstra C, et al. Limited benefit of inversely optimised intensity modulation in breast-conserving radiotherapy with simultaneously integrated boost. Radiother Oncol 2010;94:307-12. Chapter 5 Five year outcomes of hypofractionated simultaneous integrated boost irradiation in breast-conserving therapy: Patterns of recurrence E.J. Bantema-Joppe, E.J. Vredeveld, G.H. de Bock, D.M. Busz, M. Woltman-van Iersel, W.V. Dolsma, H.P. van der Laan, J.A. Langendijk and J.H. Maduro Radiother Oncol. 2013 Aug; 108(2): 269 72.

Chapter 5 Abstract In 2005, we introduced hypofractionated 3-dimensional conformal radiotherapy with a simultaneous integrated boost (3D-CRT-SIB) technique after breast-conserving surgery. In a consecutive series of 752 consecutive female invasive breast cancer patients (stages I-III) the 5-year actuarial rate for local control was 98.9%. This new technique gives excellent 5-year local control. Introduction In breast cancer, three-dimensional conformal radiotherapy with a simultaneous integrated hypofractionated boost (3D-CRTSIB) technique can be applied as part of breast-conserving therapy (BCT). In 3D-CRT-SIB, breast and boost beams are combined in one integrated treatment plan and are given simultaneously 1. This technique was adopted as standard by our department in 2005. The technique and fractionation schedule have been described in more detail by van der Laan et al. 1. Advantages of the 3D-CRTSIB compared to the conventional sequential boost technique are increased dose homogeneity with less unintended excessive dose outside the boost area, in combination with a higher dose per fraction to the tumour bed, resulting in a shorter overall treatment time 1. Previously, we reported the 3-year outcomes, with a local control and overall survival of 99.6%, and 97.1%, respectively 2. In addition, no differences were observed with regard to late toxicity and cosmetic outcome as compared to those observed after the sequential boost technique 3. The aim of this paper was to present the updated 5-year clinical outcomes and to study prognostic factors of recurrent disease in a large consecutive series of women with invasive breast cancer treated with 3D-CRT-SIB irradiation after breast-conserving surgery. Patients and methods 58 From January 2005 to January 2008, 752 consecutive female invasive breast 59 cancer patients (stages I III) were treated with 3D-CRT-SIB as part of BCT at the department of Radiation Oncology of the University Medical Center Groningen 2. Patients were irradiated with 28 fractions of 1.8 Gy to the whole breast and 2.3 Gy (76%) or 2.4 Gy (in case of focal irradicality) to the surgical bed. Adjuvant chemotherapy, hormonal treatment, monoclonal antibodies and regional radiotherapy were prescribed according to the national guidelines. Indications for regional radiotherapy were more than 3 positive axillary lymph nodes or a positive apical lymph node. The apical lymph node was defined as the most cranially positioned lymph node in the axillary dissection specimen as marked by the surgeon. Indications for internal mammary nodes (IMN) radiotherapy were medial located tumours with indication for regional radiotherapy, pathological positive IMN sentinel node, and sentinel node drainage to the IMN lymph nodes, which was not removed during surgery. Excluded were patients with previous invasive malignancies (except for non-melanoma skin cancer), previous thoracic irradiation, patients diagnosed with synchronous bilateral breast cancer, and patients treated with neo-adjuvant chemotherapy. Data were retrospectively collected and updated from the medical files. At diagnosis, median age was 58.4 (range 26-84) years (Table 1). Local recurrence (LR) was defined as any recurrence, either invasive or in situ carcinoma in the ipsilateral breast or overlying skin. Regional recurrence (RR) was defined as recurrence in the ipsilateral axillary, supraclavicular or internal mammary

Table 1. Patient and tumour characteristics (n = 752) Chapter 5 Characteristic n (%) Age at diagnosis (y) 50 204 (27.1) >50 548 (72.9) Pathologic T-stage T1 561 (74.6) T 2 191 (25.4) Pathologic N-stage (n = 749) N0 521 (69.6) N1 191 (25.5) N 2 37 (4.9) Status resection margins (n = 744) Negative 635 (85.4) (Focally) positive 109 (14.6) Differentiation grade (n = 743) I/II 550 (74.0) III 193 (26.0) Oestrogen receptor (ER) (n = 721) Positive 595 (82.5) Negative 126 (17.5) Progesterone receptor (PR) (n= 719) Positive 514 (71.5) chain lymph nodes without clinical or radiologic evidence of distant metastases. Locoregional recurrence (LRR) was defined as either local or regional recurrence. Both LRR and distant metastases (recurrent disease) were included in recurrence-free period (RFP), and presented as 1-minus the cumulative incidence of recurrent disease. Only first events were considered in the described endpoints. Distant metastases free-survival (DMFS) was the exception, as all occurring distant metastases were included. Death of any cause was used for overall survival (OS). All endpoints were calculated from the date of diagnosis of primary breast cancer to the date of the event of interest or date of last follow-up. Survival curves, including the unadjusted 5-year actuarial rates of lo- 60 Negative 205 (28.5) cal control (LC), locoregional control last follow-up. Initially, none of the patients with a RR was irradiated regionally. HER2 (n = 695) (LRC), RFP, DMFS, disease specific In Table 2 all LRRs are listed according to intrinsic subtype. 61 Positive 69 (9.9) survival (DSS) and OS were estimated Distant metastases as first event occurred in 39 (5%) patients, of which 19 Negative 626 (90.1) with the Kaplan Meier method. (49%) died of these metastases. Seven patients with a LRR developed distant Intrinsic subtypes 1 Multivariate Cox proportional hazard metastases and died. In total, 51 (7%) patients died during follow-up of which 26 Luminal 577 (76.7) analysis with backward selection was (51%) were due to breast cancer. HER2-enriched 24 (3.2) used to study prognostic factors of Other causes of death were second cancers (n = 10; 20%), cardiovascular (n = Basal 93 (12.4) RFP (recurrent disease). A two-sided 3; 6%), suicide (n = 1; 2%), liver cirrhosis (n = 1; 2%), pneumonia (n = 1; 2%), Unknown 58 (7.7) p value of <0.05 was considered statistically and unknown (free of disease at last follow-up) (n = 8; 16%). Adjuvant chemotherapy significant. No 486 (64.2) Table 2. Patterns of failure in relation to intrinsic subtypes (n = 752) Yes 269 (35.8) Adjuvant hormonal therapy No 461 (61.2) Yes 292 (38.8) Adjuvant trastuzumab No 715 (95.1) Yes 37 (4.9) Regional radiotherapy No 707 (94.0) Yes 45 (6.0) Abbreviations: HER2 = human epidermal growth factor receptor 2. 1 Luminal: ER positive and/or PR positive; HER2-enriched = ER negative, PR negative, HER2 positive = Basal: ER negative, PR negative, HER2 negative. Results Median follow-up was 60 (range 3-93) months. In total, 7 (0.9%) patients had an isolated LR, of which 5 (71%) were invasive and 2 (29%) pure DCIS histology. Four patients had an invasive isolated LR, located below the lumpectomy scar and within the boost planning target volume (PTV). The other three isolated local recurrences were at distance from the primary site, outside the boost PTV. All local recurrences were treated with a mastectomy. Eight months after primary treatment, one of these patients developed a second LR, and was treated with local excision, radiotherapy and hyperthermia. All these patients are alive without evidence of disease at lastfollow-up. Five (0.7%) patients had an isolated RR, as first event. These isolated RRs were located in the ipsilateral axillary lymph nodes in 3 (60%) patients, in 1 (20%) patient in the supraclavicular nodal area, and in the IMN combined with supraclavicular nodal metastases in 1 (20%) patient. In 2 out of the 3 patients with an ipsilateral axillary lymph node recurrence, this recurrence was located in the cranial part of axilla level I. In the third patient, the ipsilateral regional recurrence was located in the interpectoral lymph nodes. Only the patient with the supraclavicular recurrence was node-positive at primary diagnosis (N1). Two (0.3%) patients relapsed locally, regionally and at distant sites simultaneously. The first patient developed lymphangitis carcinomatosa with concurrent supraclavicular and distant metastases at 14 months of follow-up. The second patient presented with axillary and supraclavicular metastases, combined with skin metastases and distant metastases, 6.5 years after surgery. Both patients died of disease. Three (0.4%) patients relapsed both regionally and distant simultaneously. The RRs were all located supraclavicular and in one patient combined with the IMN. One of these 3 (33%) patients died and the other 2 patients were disease-free at HER2- Luminal enriched Basal Unknown Total First event n (%) n (%) n (%) n (%) n (%) Local recurrence (LR) 1 7 (17.9) 0 2 (13.3) 0 9 (16.1) Regional recurrence (RR) 2 5 (12.8) 0 3 (20.0) 0 8 (14.3) Distant metastases (DM) 27 (69.2) 2 (100) 10 (66.7) 0 39 (69.6) Total 39 (6.8) 2 (8.3) 15 (16.1) 0 56 (7.4) No event 538 (93.2) 22 (91.7) 78 (83.9) 58 (100) 696 (92.6) 1 two patients developed LR, RR and DM simultaneously. 2 three patients developed RR and DM simultaneously.

Chapter 5 Number at risk 0y 1y 2y 3y 4y 5y 5-year % (95% CI) LC 752 747 733 707 659 376 98.9 (98.1-99.7) DMFS 752 744 726 695 645 369 94.2 (92.4-96.0) OS 752 747 738 687 589 380 93.3 (91.3-95.3) The unadjusted 5-year actuarial rate of LC was 98.9% (95% CI 98.1-99.7), LRC 97.8% (95% CI 96.6-99.0), RFP 93.1% (95% CI 91.1-95.1), DMFS 94.2% (95% CI 92.4-96.0), DSS 96.8 (95% CI 95.4-98.2), and OS was 93.3% (95% CI 91.3-95.3), respectively. The survival curves for LC, DMFS, and OS are presented in Figure. 1. In total, 41 (6%) patients developed a secondary malignancy during follow-up. Eighteen out of these 41 (44%) patients had contralateral breast cancer. All tumours were Fig. 1. Kaplan-Meier curves with actuarial 5-year local control (LC) (dotted 62 line), distant metastases free-survival (DMFS) (black), and overall survival to the standard fractionation. Another explanation for the high LC rate could be invasive tumours. Other 63 (OS) (gray) (with corresponding 95% confidence intervals (CI)), including secondary tumour sites number at risk. were ovaries in 1 (2%) patient; endometrium in 2 (5%); oesophagus in 1 (2%); other gastro-intestinal tract in 9 (22%); lung in 5 (12%); and head and neck in 2 (5%) patients. Furthermore, 2 (5%) patients developed acute myeloid leukaemia, 1 (2%) patient a non-hodgkin lymphoma, and another (2%) patient a glioblastoma multiforme. Ten patients died of the secondary malignancy (at other sites than the contralateral breast). Patients with basal intrinsic subtype tumours, defined as oestrogen receptor negative, progesterone receptor negative, and human epidermal growth factor (HER-2) receptor negative (i.e., triple negative tumours) were at higher risk of recurrent disease, compared to patients with tumours of other subtypes (i.e., receptor positive breast cancer (HR 2.6, 95% CI 1.4-4.8, p = 0.002). Tumours with a diameter of more than 2 cm were associated with more recurrent disease (HR 2.7, 95% CI 1.5-4.7, p = 0.001). Furthermore, patients with more than 3 positive lymph nodes developed more recurrent disease than patients without positive lymph nodes (HR 2.7, 95% CI 1.2-6.3, p = 0.01, N0 as reference group). No increased risk of recurrent disease was observed between patients with 1-3 positive lymph nodes compared to patients with N0-disease (HR 0.9, 95% CI 0.5-1.7, p = 0.76). Discussion In this paper, the updated 5-year clinical outcomes are presented of a consecutive series of 752 patients treated with hypofractionated 3D-CRT-SIB for invasive breast cancer as part of BCT. Compared to other series in a comparable series of patients treated with an additional boost, these results are excellent. The 5-year results of the boost arm of the EORTC study 22881 10882, whole breast irradiation with a sequential boost, were 92.7% (95% CI 92.4-93.2) for LC, 91% (95% CI n.a.) for OS, and 87% (95% CI n.a.) for DMFS 4. The risk of developing a new primary in the contralateral breast is higher than that of an in-breast recurrence. Furthermore, 3 of the 7 local recurrences were at a distance from the primary tumour, and could therefore be considered as secondary primaries. This means that the applied treatment strategies are effective in preventing both true local recurrences, and second primaries in the ipsilateral breast. Several factors can be attributed to the high LC rate of our hypofractionated 3D-CRT-SIB series. One of the explanations could be the introduction of CT-planning, resulting in better definition of the boost target volume. Furthermore, the SIB-fractionation schedule used in the present series was based on an equivalent dose for tumour control using an α/β ratio of 10. Current knowledge suggests a lower a/b ratio of 4.6 for tumour control 5, resulting in a higher biologically effective dose when compared to calculations with an α/β ratio of 10. This could result in a therapeutic advantage of present hypofractionated regimen compared the increased use of systemic therapy in the present series. Additionally, in the 18 patients who developed contralateral breast cancer, only 1 patient was treated with hormonal and chemotherapy (data not shown). This supports the idea that new contralateral tumours in women with breast cancer could be prevented by the use of hormonal therapy 6. Several studies suggested a relation between the occurrence of local recurrences and the development of distant metastases 7-9. By avoiding 4 local recurrences one breast cancer-related death can be prevented 10. Besides the improved LC, we also observed less distant metastases as seen in a decreased DMFS compared to the boost-study (94.2% vs. 87%). In conclusion, the use of hypofractionated 3D-CRT-SIB as part of breast-conserving therapy results in excellent 5-year local control rates. References 1. van der Laan HP, Dolsma WV, Maduro JH, Korevaar EW, Hollander M, Langendijk JA. Three-dimensional conformal simultaneously integrated boost technique for breast-con serving radiotherapy. Int J Radiat Oncol Biol Phys 2007;68:1018 23. 2. Bantema-Joppe EJ, van der Laan HP, de Bock GH, et al. Three-dimensional conformal hypofractionated simultaneous integrated boost in breast-conserving therapy: results on local control and survival. Radiother Oncol 2011;100:215 20. 3. Bantema-Joppe EJ, Schilstra C, de Bock GH, et al. Simultaneous integrated boost irradiation after breast-conserving surgery: physician-rated toxicity and cosmetic out