Cancer du sein sans atteinte ganglionnaire axillaire

Contouring workload in adjuvant breast cancer radiotherapy

PURPOSE

To measure the impact of contouring on worktime in the adjuvant radiation treatment of breast cancer, and to identify factors that might affect the measurements.

MATERIAL AND METHODS

The dates and times of contouring clinical target volumes and organs at risk were recorded by a senior and by two junior radiation oncologists. Outcome measurements were contour times and the time from start to approval. The factors evaluated were patient age, type of surgery, radiation targets and setup, operator, planning station, part of the day and day of the week on which the contouring started. The Welch test was used to comparatively assess the measurements.

RESULTS

Two hundred and three cases were included in the analysis. The mean contour time per patient was 34minutes for a mean of 4.72 structures, with a mean of 7.1minutes per structure. The clinical target volume and organs at risk times did not differ significantly. The mean time from start to approval per patient was 29.4hours. Factors significantly associated with longer contour times were breast-conserving surgery (P=0.026), prone setup (P=0.002), junior operator (P<0.0001), Pinnacle planning station (P=0.026), contouring start in the morning (P=0.001), and contouring start by the end of the week (P<0.0001). Factors significantly associated with time from start to approval were age (P=0.038), junior operator (P<0.0001), planning station (P=0.016), and contouring start by the end of the week (P=0.004).

CONCLUSION

Contouring is a time-consuming process. Each delineated structure influences worktime, and many factors may be targeted for optimization of the workflow. These preliminary data will serve as basis for future prospective studies to determine how to establish a cost-effective solution.

Adjuvant radiotherapy in the management of axillary node negative invasive breast cancer: a qualitative systematic review

PURPOSE

To actualize and to detail guidelines used in technical radiotherapy and indications for innovative radiation technologies in early axillary node negative breast cancer (BC).

METHODS

Dosimetric and treatment planning studies, phase II and III trials, systematic reviews and retrospective studies were all searched (Medline(®) database). Their quality and clinical relevance were also checked against validated checklists. A level of evidence was associated for each result.

RESULTS

A total of 75 references were included. Adjuvant BC radiotherapy (50Gy/25 fractions/5 weeks followed by a tumor boost of 16Gy/8 fractions) is still the standard of care. Overall treatment time could be shortened for patients who present with low local relapse risk BC by using either hypofractionated whole breast irradiation; or accelerated partial breast irradiation. BC IMRT is not used in current practice.

CONCLUSION

Our group aimed to provide guidelines for technical and clinical applications of innovative BC radiation technologies.

[Organs at risk and target volumes: definition for conformal radiation therapy in breast cancer]

Adjuvant radiotherapy is a standard component of breast cancer treatment. The addition of radiotherapy after breast conserving surgery has been shown to reduce local recurrence rate and improve long-term survival. Accurate delineation of target volumes and organs at risk is crucial to the quality of treatment planning and delivered accomplished with innovate technologies in radiation therapy. This allows the radiation beam to be shaped specifically to each individual patient's anatomy. Target volumes include the mammary gland and surgical bed in case of breast conserving surgery, the chest wall in case of mastectomy, and if indicated, regional lymph nodes (axillary, supra- and infraclavicular and internal mammary). Organs at risk include lungs, thyroid, brachial plexus, heart, spinal cord and oesophagus. The aim of this article is to encourage the use of conformal treatment and delineation of target volumes and organs at risk and to describe specifically the definition of these volumes.

Higher toxicity with 42 Gy in 10 fractions as a total dose for 3D-conformal accelerated partial breast irradiation: results from a dose escalation phase II trial

Objective

Recent recommendations regarding indications of accelerated partial breast irradiation (APBI) have been put forward for selected breast cancer (BC) patients. However, some treatment planning parameters, such as total dose, are not yet well defined. The Institut Gustave Roussy has initiated a dose escalation trial at the 40 Gy/10 fractions/5 days and at a further step of total dose (TD) of 42 Gy/10 fractions/ 5 days. Here, we report early results of the latest step compared with the 40 Gy dose level.

Methods and materials

From October 2007 to March 2010, a total of 48 pT1N0 BC patients were enrolled within this clinical trial: 17 patients at a TD of 42 Gy/10f/5d and 31 at a TD of 40 Gy/10f/5d. Median follow-up was 19 months (min-max, 12–26). All the patients were treated by APBI using a technique with 2 minitangents and an “enface” electrons delivering 20% of the total dose. Toxicities were systematically assessed at 1; 2; 6 months and then every 6 months.

Results

Patients’ recruitment of 42 Gy step was ended owing to persistent grade 3 toxicity 6 months after APBI completion (n = 1). Early toxicities were statistically higher after a total dose of 42 Gy regarding grade ≥2 dry (p = 0.01) and moist (p = 0.05) skin desquamation. Breast pain was also statistically higher in the 42 Gy step compared to 40 Gy step (p = 0.02). Other late toxicities (grade ≥2 fibrosis and telangectasia) were not statistically different between 42 Gy and 40 Gy.

Conclusions

Early toxicities were more severe and higher rates of late toxicities were observed after 42 Gy/10 fractions/5 days when compared to 40 Gy/10 fractions/5 days. This data suggest that 40 Gy/10 fractions/ 5 days could potentially be the maximum tolerance for PBI although longer follow-up is warranted to better assess late toxicities.

[Role of locoregional radiation therapy in breast cancer patients with negative lymph nodes after preoperative chemotherapy and mastectomy. The Institut Curie-Hôpital René-Huguenin experience]

PURPOSE

Neoadjuvant chemotherapy generally induces significant changes in the pathological extent of disease and challenges the standard indications of adjuvant postmastectomy radiation therapy. We retrospectively evaluated the impact of postmastectomy radiation therapy in breast cancer patients with negative lymph nodes (pN0) after neoadjuvant chemotherapy.

PATIENTS AND MATERIALS

Among 1054 breast cancer patients treated with neoadjuvant chemotherapy in our institution between 1990 and 2004, 134 patients had pN0 status after neoadjuvant chemotherapy and mastectomy. Demographic data, tumor characteristics, metastatic sites, and treatments were prospectively recorded. The impact of postmastectomy radiation therapy on locoregional recurrence-free survival and overall survival was evaluated by multivariate analysis including known prognostic factors.

RESULTS

Among 134 eligible patients, 78 patients (58.2%) received postmastectomy radiation therapy, and 56 patients (41.8%) did not. With a median follow-up time of 91.4 months, the 10-year locoregional recurrence-free survival and overall survival rates were 96.2% and 77.2% with postmastectomy radiation therapy and 86.8% and 87.7% without radiation therapy, respectively (no significant difference). In multivariate analysis, there was a trend towards poorer overall survival among patients who did not have a pathologically complete primary tumour response after neoadjuvant chemotherapy (hazard ratio [HR], 6.65; 95% CI, 0.82-54.12; P=0.076). Postmastectomy radiation therapy had no effect on either locoregional recurrence-free survival (HR, 0.37; 95% CI, 0.09-1.61; P=0.18) or overall survival (HR, 2.06; 95% CI, 0.71-6; P=0.18). There was a trend towards poorer overall survival among patients who did not have pathologically complete in-breast tumour response after neoadjuvant chemotherapy (HR, 6.65; 95% CI, 0.82-54.12; P=0.076).

CONCLUSIONS

This retrospective study showed no increase in the risk of distant metastasis, locoregional recurrence or death when postmastectomy radiation therapy was omitted in breast cancer patients with pN0 status after neoadjuvant chemotherapy and mastectomy. Whether the omission of postmastectomy radiation therapy is acceptable for these patients should be addressed prospectively.

[Exclusive radiotherapy and concurrent endocrine therapy for the management of elderly breast cancer patients: case study and review of hypofractionated schemes]

Normofractionated radiotherapy is standard for adjuvant management of patients treated with breast conservative surgery for breast cancer. However, many elderly patients are not eligible to such strategy, either because of concurrent diseases, or because the tumor is inoperable. Several protocols of exclusive radiotherapy have been reported in the literature, frequently using hypofractionated radiotherapy and endocrine therapy. We report a case of a patient treated with exclusive endocrine and radiotherapy and address the state of the art on hypofractionated schemes for the management of elderly breast cancer patients. While hypofractionated radiotherapy does not compromise the oncologic or cosmetic outcome, there is no prospective data that assesses the place of radiotherapy for the exclusive treatment of elderly patients. This strategy should be further assessed in clinical randomized trial.