radiation treatment

Certain patients are candidates for modified radical mastectomy. A few of these patients require chest wall radiation. The increasing awareness of self-image and psychological issues make breast reconstruction an option for some of these patients. The reconstruction can be performed after radiation to the chest wall or at the time of radical mastectomy. Surgical augmentation following radiation to the chest wall is fraught with complications and adverse cosmetic effects exist. Many women opt for immediate breast reconstruction using autologous tissue (flaps) or by the insertion of a temporary prosthesis. Presence of the breast mound soon after radical breast surgery is also known to add to the psychological benefits.

In a few individuals, following radical mastectomy, the lack of adequate skin covering over the chest wall makes placement of breast prosthesis difficult. This can be overcome by the use of temporary tissue expanders to create an adequate skin volume. The permanent prosthesis can then be accommodated at a later stage. silagra 100

In such patients, while awaiting adequate skin expansion and with a temporary tissue expander in place, radiotherapy may be required to prevent loco-regional relapse. Criteria for patients requiring radiation following mastectomy include presence of positive deep surgical margins, four or more involved axillary lymph nodes, extra capsular nodal extension, skin involvement, stages ТЗ, T4 and N3 and recurrent breast carcinoma.

The compatibility of radiation treatment and breast reconstruction using temporary tissue expanders is of serious concern. Even though immediate reconstruction is practiced there is concern that temporary tissue expander may perform suboptimally following exposure to radiation. The complications of radiation include improper filling of the expander, spontaneous expander deflation problems, rib denting, deformation of the thoracic cage, expansion without projection, thinning of tissues over the prosthesis, and necrosis of adjacent tissues. The complications related to radiotherapy are radiation induced endovasculitis and destruction of the network of elastin fibers.

Sometimes the prosthetic devices can develop microscopic leaks causing accumulation of fluid under the tissues. This can lead to inflammation, infection and edema due to such leakages. Such accumulations may not be detectable during routine physical examination, unless imaging studies are performed. The collection of fluid under tissue planes can also act as boluses and cause hot and cold spots in the radiation field. These distortions in dose distribution can lead to tissue necrosis and failure of treatment. Thus keeping the amount of fluid in the prosthesis constant as well as monitoring the treatment volume by suitable imaging techniques are critical aspects of radiation treatment.

Timing of radiation therapy is crucial for avoiding loco regional relapse. This is optimally done within 12-16 weeks of surgery. It is crucial that the radiation oncologist works along with the surgeon and educates the team about the role they play in such a setting. As most patients have their tissue expander prosthesis inflated by the surgeons, it is important to understand that slow and regular filling of the prosthesis by injection of saline is favored over a rapid and irregular filling technique.

Current literature is full of references pertaining to cosmetic outcomes following breast reconstruction. As part of treatment planning and quality assurance physicists have compared dosimetry data for photon and electron beam radiation. In patients with breast reconstruction, the dose volume histograms (DVH) and differential DVH (dDVH) analysis have been performed in order to identify regions that are under dosed or over dosed (cold and hot spots). Drastic changes in DVH can result due to leakage of fluid form the expander or due to deformation of the prosthesis. Such deformation and leakage of fluid should be discernable from MRI or radiologic imaging. To date DVH analysis carried out have not been fruitful in detecting suboptimal performance of the expander. Also such analysis has the disadvantage of not alerting us to very early changes before they become a major problem.

Current literature however, provides little clinical information on our ability to closely monitor the prosthesis during the course of radiation treatment. The purpose of our study was to add an imaging tool to verify any ongoing changes to the expander during the course of radiation. Viagra Online Canadian Pharmacy

Physicists and other researchers have conducted studies on phantoms with breast implants. Phantom dosimetry data demonstrated no hot or cold spots due to the prosthesis. These studies demonstrated that the prosthesis itself did not affect photon beam distribution. Other studies, wherein a permanent prosthesis is placed immediately following radical breast surgery did not lead to satisfactory results. This was attributed to radiation-induced effects on certain permanent prosthesis depending on its composition. For example a silicon breast prosthesis or tissue equivalent gels may undergo substantial changes like discoloration and loss of tensile strength and elasticity. While the prosthesis themselves do not compromise dose distribution to the tumor bed, the durability of the prosthesis can be affected by radiation. There is concern that such adverse effects can make any future breast implants impractical. The use of a temporary tissue expander filled with saline negates these effects and may be a better option for the cosmetically concerned women.

Carrying out a second simulation during the course of radiation may minimize the risk of adverse effects due to temporary breast prosthesis. While this may not be an issue for the radiation oncologist, it does inconvenience the patient and the therapy staff.

Additionally certain patients are not candidates for this form of treatment. They are patients known to have poor healing due to diabetics, connective tissue disorders, and vasculopathies. Also patients on chemotherapy may not be ideal candidates. It may be relatively contraindicated in some older women. suhagra 100

By the addition of an imaging technique, we can observe the changes occurring in the prosthesis. This is a non-invasive technique with very little inconvenience to the team as well as no adverse effects.