Breast cancer

The incidence of this disease in the population is moerately decreasing due to prevention campaigns. However, it is estimated that one in 10 women will develop breast cancer during  life.

The mortality rate has decreased due to new technologies by 40.58/100.000 to 33.84/100.000 (-17%) in the period 1982-2002 (Bosetti et al. 2008).

The diagnosis of cancer before 2 cm is now feasible, especially in women after age of 50 when the breast is rich in fat tissue. The earlier the diagnosis is made, the least the intervention results destructive.

Treatment of breast cancer

Conservative techniques such as lumpectomy (removal of the tumor with 2 cm of healthy surroundins tissue) are the standard protocols for tumors smaller than 2 cm.

IORT can be applied in a single dose in the case of treatment of breast cancer at stage I in postmenopausal women: the patient receives a single dose of 21 Gy during surgery. 

Thus 80 seconds  replace the need for 30 sessions of conventional external radiotherapy.

Treatment of breast cancer is becoming more conservative and includes surgical techniques that spare the anatomy of the breast (quadrantectomy, segmental mastectomy and lumpectomia) and allow the axillary staging by sentinel lymph node biopsy (SLN), with cosmetic benefits and improvement in quality patient's life by reducing the risk of ipsilateral limb edema, usually associated with conventional axillary dissection.

The success of the partial intervention is similar to that achieved with radical surgery, but requires the the external radiotherapy treatment to be conducted at least for 4 or 6 weeks to achieve similar results.

Partial breast irradiation using IORT may have results equivalent total external irradiation in cases of breast sparing surgery, with the added benefits of a single dose administration, low cost and minimal side effects. The adverse effect of external breast irradiation consists in a loss of 6% of ipsilateral lung function, a residual hyperpigmentation, persistent edema which requires continuous physiotherapy, hypersensitivityand the need to interrupt the treatment treatment in large breasts or in obese patients.

The need for additional radiotherapy to the breast sparing surgery was emphasized in some studies following the observation of local recurrencies in patients who underwent irradiation.

IORT therefore opens new prospects of radiotherapy treatment for breast cancer.

The association of an intraoperative radiotherapy boost and external beam radiation therapy represents the most effective approach to prevent relapse.

The ideal treatment is the external administration of a tolerable dose (45-50 Gy) of radiation before or after the surgical resection, IORT and local targeting by removing the sensitive tissues.

Clinical evidence

In the study, the abitual 5 weeks of fractionated external radiotherapy were replaced by 70 seconds of IORT treatment.

The group of Prof. Veronesi and  Prof. Lesti started in Italy in 2001 to follow a cohort of women over age 50 with tumors below 2.5 cm who underwent lumpectomy and treated them with IORT whit a single dose of 21 Gy delivered to the breast quadrant of the tumor site.

A 21 Gy single dose  has a radiobiologicalvalue of about 55 Gy.

The time required for the whole procedure (device setting, positioning the collimator, irradiation of the tumor, removal of the device) didn't exceed 10-15 minutes, while the irradiation time lasted not more than 70-80 seconds .

2% to 2.2% of local recurrencies were found in the group of Veronesi against a 6-8% documented in the literature with external radiotherapy.

In addition to the coupling of conservative surgery / radiotherapy, already proven as the most effective, the IORT technique minimizes the damage to adjacent healthy tissue (coronary vessels, lungs and skin), and eliminates all waiting times and post-operative radiotherapy sessions with significant reduction in waiting time for both patients and the healthcare facility.

To be effective, external radiation therapy should be started within 30 days after surgery, while waiting times in Italy vary from 3 to 6 months. 

Further  benefits include low cost of the procedure compared to conventional external beam radiation therapy (approximately three quarters of the price of the conventional one).