Sequencing of chemotherapy and radiation therapy for early breast cancer

Interdisciplinary Screening, Diagnosis, Therapy and Follow-up of Breast Cancer. Guideline of the DGGG and the DKG (S3-Level, AWMF Registry Number 032/045OL, December 2017) - Part 2 with Recommendations for the Therapy of Primary, Recurrent and Advanced Breast Cancer

Purpose The aim of this official guideline coordinated and published by the German Society for Gynecology and Obstetrics (DGGG) and the German Cancer Society (DKG) was to optimize the screening, diagnosis, therapy and follow-up care of breast cancer. Method The process of updating the S3 guideline published in 2012 was based on the adaptation of identified source guidelines. They were combined with reviews of evidence compiled using PICO (Patients/Interventions/Control/Outcome) questions and with the results of a systematic search of literature databases followed by the selection and evaluation of the identified literature. The interdisciplinary working groups took the identified materials as their starting point and used them to develop suggestions for recommendations and statements, which were then modified and graded in a structured consensus process procedure. Recommendations Part 2 of this short version of the guideline presents recommendations for the therapy of primary, recurrent and metastatic breast cancer. Loco-regional therapies are de-escalated in the current guideline. In addition to reducing the safety margins for surgical procedures, the guideline also recommends reducing the radicality of axillary surgery. The choice and extent of systemic therapy depends on the respective tumor biology. New substances are becoming available, particularly to treat metastatic breast cancer.

Timing of radiotherapy following breast-conserving surgery: outcome of 1393 patients at a single institution

BACKGROUND

The role of postoperative radiotherapy in breast-conserving therapy is undisputed. However, optimal timing of adjuvant radiotherapy is an issue of ongoing debate. This retrospective clinical cohort study was performed to investigate the impact of a delay in surgery-radiotherapy intervals on local control and overall survival.

PATIENTS AND METHODS

Data from an unselected cohort of 1393 patients treated at a single institution over a 17-year period (1990-2006) were analyzed. Patients were assigned to two groups (CT+/CT-) according to chemotherapy status. A delay in the initiation of radiotherapy was defined as > 7 weeks (CT- group) and > 24 weeks (CT+ group).

RESULTS

The 10-year regional recurrence-free survival for the CT- and CT+ groups were 95.6 and 86.0 %, respectively. A significant increase in the median surgery-radiotherapy interval was observed over time (CT- patients: median of 5 weeks in 1990-1992 to a median of 6 weeks in 2005-2006; CT+ patients: median of 5 weeks in 1990-1992 to a median of 21 weeks in 2005-2006). There was no association between a delay in radiotherapy and an increased local recurrence rate (CT- group: p = 0.990 for intervals 0-6 weeks vs. ≥ 7 weeks; CT+ group: p = 0.644 for intervals 0-15 weeks vs. ≥ 24 weeks) or decreased overall survival (CT- group: p = 0.386 for intervals 0-6 weeks vs. ≥ 7 weeks; CT+ group: p = 0.305 for intervals 0-15 weeks vs. ≥ 24 weeks).

CONCLUSION

In the present cohort, a delay of radiotherapy was not associated with decreased local control or overall survival in the two groups (CT-/CT+). However, in the absence of randomized evidence, delays in the initiation of radiotherapy should be avoided.

Structural/organizational characteristics of health services partly explain racial variation in timeliness of radiation therapy among elderly breast cancer patients

Observed racial/ethnic disparities in the process and outcomes of breast cancer care may be explained, in part, by structural/organizational characteristics of health care systems. We examined the role of surgical facility characteristics and distance to care in explaining racial/ethnic variation in timing of initiation of guideline-recommended radiation therapy (RT) after breast conserving surgery (BCS). We used Surveillance Epidemiology and End Results-Medicare data to identify women ages 65 and older diagnosed with stages I-III breast cancer and treated with BCS in 1994-2002. We used stepwise multivariate logistic regression to examine the interactive effects of race/ethnicity and facility profit status, teaching status, size, and institutional affiliations, and distance to nearest RT on timing of RT initiation, controlling for known covariates. Among 38,574 eligible women who received BCS, 39% received RT within 2 months, 52% received RT within 6 months, and 57% received RT within 12 months post-diagnosis, with significant variation by race/ethnicity. In multivariate models, women attending smaller surgical facilities and those with on-site radiation had higher odds of RT at each time interval, and women attending governmental facilities had lower odds of RT at each time interval (P < 0.05). Increasing distance between patients' residence and nearest RT provider was associated with lower overall odds of RT, particularly among Hispanic women (P < 0.05). In fully adjusted models including race-by-distance interaction terms, racial/ethnic disparities disappeared in RT initiation within 6 and 12 months. Racial/ethnic disparities in timing of RT for breast cancer can be partially explained by structural/organizational health system characteristics. Identifying modifiable system-level factors associated with quality cancer care may help us target policy interventions that can reduce disparities in outcomes.

Waiting times for radiotherapy after breast-conserving surgery and the association with survival: a path analysis

AIMS

To investigate the association between radiotherapy waiting times and survival in women who have undergone breast-conserving surgery using data from two English cancer registry regions. The data were analysed using path analysis to account for the complex variable interrelationships within the data.

MATERIALS AND METHODS

Cases of female invasive breast cancer diagnosed during the period 1 January 1998 to 31 December 2005 were identified and linked to an extract of Hospital Episode Statistics data. A subset of these linked records where women underwent breast-conserving surgery was extracted (n=18,158). Patient, tumour and treatment information were extracted. A path model was developed with three outcome variables: survival, time to receive radiotherapy and receipt of chemotherapy before radiotherapy.

RESULTS

During the study period, the median radiotherapy waiting time in region 1 increased from 70 days to 128.5 days. In region 2, the median wait increased from 44 days in 1998 to 68 days in 2001, then decreased to 42 days by 2005. In the path model, radiotherapy waiting time was not associated with survival (hazard ratio=1.00, 95% confidence interval 0.99-1.01 per week increase in both regions). Patients receiving chemotherapy before radiotherapy waited 12.3 weeks (region 1) and 6.3 weeks (region 2) longer for their radiotherapy than those not receiving chemotherapy. Patients with stage II/III disease waited longer than patients with stage I disease. Younger age, diagnosis of stage II/III disease and presence of co-morbidities were associated with increased odds of receiving chemotherapy before radiotherapy.

CONCLUSIONS

This study found no association between waiting times for radiotherapy and survival in two regions of England, despite increases in waiting times over the study period. Such an association, if real, may only become apparent after a longer period of follow-up.

Optimal sequence of implied modalities in the adjuvant setting of breast cancer treatment: an update on issues to consider

The adjuvant setting of early breast cancer treatment is an evolving field where different modalities must be combined to improve outcomes; moreover, quality of life of breast cancer survivors emerges as a new important parameter to consider, thus implying a better understanding of toxicities of these modalities. We have conducted a review focusing on the latest literature of the past 3 years, trying to evaluate the existing data on the maximum acceptable delay of radiotherapy when given as sole adjuvant treatment after surgery and the optimal sequence of all these modalities with respect to each other. It becomes evident radiotherapy should be given as soon as possible and within a time frame of 6-20 weeks. Chemotherapy is given before radiotherapy and hormone therapy. However, radiotherapy should be started within 7 months after surgery in these cases. Hormone therapy with tamoxifen might be given safely concomitantly or sequentially with radiotherapy although solid data are still lacking. The concurrent administration of letrozole and radiotherapy seems to be safe, whereas data on trastuzumab can imply only that it is safe to use concurrently with radiotherapy. Randomized comparisons of hormone therapy and trastuzumab administration with radiotherapy need to be performed.

Breast cancer during pregnancy

Breast cancer in pregnancy is an uncommon situation but poses dilemmas for patients and their physicians. There is a paucity of prospective studies regarding diagnosis and treatment of breast cancer during pregnancy. Women diagnosed with breast cancer during pregnancy have similar disease characteristics to age-matched controls. Current evidence suggests that diagnosis may be carried out with limitations regarding staging. Surgical treatment may be performed as for non-pregnant women. Radiotherapy and endocrine or antibody treatment should be postponed until after delivery. Chemotherapy is allowed after the first trimester. Physicians should be aggressive in the workup of breast symptoms in the pregnant population to expedite diagnosis and allow multidisciplinary treatment without delay.

Sequencing chemotherapy and radiotherapy in locoregional advanced breast cancer patients after mastectomy - a retrospective analysis

BACKGROUND

Combined chemo- and radiotherapy are established in breast cancer treatment. Chemotherapy is recommended prior to radiotherapy but decisive data on the optimal sequence are rare. This retrospective analysis aimed to assess the role of sequencing in patients after mastectomy because of advanced locoregional disease.

METHODS

A total of 212 eligible patients had a stage III breast cancer and had adjuvant chemotherapy and radiotherapy after mastectomy and axillary dissection between 1996 and 2004. According to concerted multi-modality treatment strategies 86 patients were treated sequentially (chemotherapy followed by radiotherapy) (SEQgroup), 70 patients had a sandwich treatment (SW-group) and 56 patients had simultaneous chemoradiation (SIM-group) during that time period. Radiotherapy comprised the thoracic wall and/or regional lymph nodes. The total dose was 45-50.4 Gray. As simultaneous chemoradiation CMF was given in 95.4% of patients while in sequential or sandwich application in 86% and 87.1% of patients an anthracycline-based chemotherapy was given.

RESULTS

Concerning the parameters nodal involvement, lymphovascular invasion, extracapsular spread and extension of the irradiated region the three treatment groups were significantly imbalanced. The other parameters, e.g. age, pathological tumor stage, grading and receptor status were homogeneously distributed. Looking on those two groups with an equally effective chemotherapy (EC, FEC), the SEQ- and SW-group, the sole imbalance was the extension of LVI (57.1 vs. 25.6%, p < 0.0001).5-year overall- and disease free survival were 53.2%/56%, 38.1%/32% and 64.2%/50%, for the sequential, sandwich and simultaneous regime, respectively, which differed significantly in the univariate analysis (p = 0.04 and p = 0.03, log-rank test). Also the 5-year locoregional or distant recurrence free survival showed no significant differences according to the sequence of chemo- and radiotherapy. In the multivariate analyses the sequence had no independent impact on overall survival (p = 0.2) or disease free survival (p = 0.4). The toxicity, whether acute nor late, showed no significant differences in the three groups. The grade III/IV acute side effects were 3.6%, 0% and 3.5% for the SIM-, SW- and SEQ-group. By tendency the SIM regime had more late side effects.

CONCLUSION

No clear advantage can be stated for any radio- and chemotherapy sequence in breast cancer therapy so far. This could be confirmed in our retrospective analysis in high-risk patients after mastectomy. The sequential approach is recommended according to current guidelines considering a lower toxicity.

MR guided cancer treatment system for an elevated therapeutic index - a macroscopic approach

Adjuvant therapy for cancer usually refers to surgery followed by chemotherapy and/or radiation treatment to decrease the risk of recurrence. But still, the absolute benefit for survival obtained with adjuvant therapy compared with control is only approximately 6%. The objective of this analysis is to formulate a non-invasive multimodal cancer treatment system related to cancer stem cells and hypoxic fractions of solid tumors, emphasizing MRI monitoring and guidance, to elevate the therapeutic index. Tumor hypoxia is a therapeutic concern since it can reduce the effectiveness of drugs and radiotherapy, where well oxygenated cells requiring one third of the dose of hypoxic cells to achieve a given level of cell killing. Cancer stem cells might be the cause of tumor recurrence, sometimes many years after the appearance of the successful treatment of a primary tumor. Thus, the primary objective of such a treatment system will be to provide sufficient selective toxicity to both kill cancer stem cells and cells of hypoxic fractions of the tumor. Active tumor targeting with the use of liposomally encapsulated drugs is the starting point of the treatment procedure. The system facilitates quality assurance means by MR monitoring of drug accumulation and drug release, in real time. Cavitation involves the nucleation, growth and oscillation of gaseous cavities. Selective drug release and/or hyperthermia are achieved by ultrasound induced cavitation well defined to the tumor region. Hyperthermic effects, increased vascularization and subsequent increase in pO2 levels to hypoxic regions, can be monitored by MRI. MRI monitoring of key physiological parameters facilitates optimization related to approximate real time concomitant treatments, including correct timing and various combinations of drug therapy, hyperthermia, ionizing radiation, ablation, other treatment options, before or after surgery. The likelihood of an improved therapeutic index with the use of such a system seems compelling. Further research related to optimal timing, combinations of responses between liposomally encapsulated drug dosage, ultrasound exposure, hyperthermia, pO2 response time, ionizing radiation fractionation and treatment time, have to be conducted.

Telomeric DNA induces apoptosis and senescence of human breast carcinoma cells

INTRODUCTION

Cancer is a leading cause of death in Americans. We have identified an inducible cancer avoidance mechanism in cells that reduces mutation rate, reduces and delays carcinogenesis after carcinogen exposure, and induces apoptosis and/or senescence of already transformed cells by simultaneously activating multiple overlapping and redundant DNA damage response pathways.

METHODS

The human breast carcinoma cell line MCF-7, the adriamycin-resistant MCF-7 (Adr/MCF-7) cell line, as well as normal human mammary epithelial (NME) cells were treated with DNA oligonucleotides homologous to the telomere 3' overhang (T-oligos). SCID mice received intravenous injections of MCF-7 cells followed by intravenous administration of T-oligos.

RESULTS

Acting through ataxia telangiectasia mutated (ATM) and its downstream effectors, T-oligos induced apoptosis and senescence of MCF-7 cells but not NME cells, in which these signaling pathways were induced to a far lesser extent. In MCF-7 cells, experimental telomere loop disruption caused identical responses, consistent with the hypothesis that T-oligos act by mimicking telomere overhang exposure. In vivo, T-oligos greatly prolonged survival of SCID mice following intravenous injection of human breast carcinoma cells.

CONCLUSION

By inducing DNA damage-like responses in MCF-7 cells, T-oligos provide insight into innate cancer avoidance mechanisms and may offer a novel approach to treatment of breast cancer and other malignancies.