Radiotherapy and Breast Reconstruction

Radiotherapy and Breast Reconstruction

Introduction

·  Postmastectomy radiotherapy generally aims to deliver broad coverage of the chest wall, treat the ipsilateral supraclavicular fossa and axillary apex (level III), avoid the heart, and minimize the amount of lung tissue within the therapy field.

·  Adequate broad chest wall coverage is commonly agreed on to be the single most important target for postmastectomy radiotherapy

·  Controversy exists regarding the inclusion of the ipsilateral internal mammary chain (IMC) region as a target – some include at least the upper ipsilateral IMC region because randomized studies have shown that patients who receive such treatment have a survival advantage.

·  heart and lung are avoided as much as possible because of concerns regarding radiation-induced heart disease (such as pericardial disease, myocardial disease, coronary artery disease, valvular defects, and conduction abnormalities) and radiation-induced pulmonary toxicity (such as pulmonary fibrosis and symptomatic pneumonitis).

Indications for chest wall radiotherapy

In general, greater than 20% risk for locoregional recurrence.

1.  T3–T4 disease at presentation

2.  pathologic involvement of 4 or more lymph nodes

3.  stage III disease.

·  Other features such as lymphovascular space invasion, margin status, and multicentricity may also impact locoregional recurrence rates.

·  goal of postmastectomy radiotherapy is to decrease the risk for locoregional recurrence by as much as two thirds and to improve patient survival, perhaps by reducing secondary dissemination

·  Use of radiotherapy is increasing with some studies showing benefit for radiotherapy if 1-3 lymph nodes involved and others showing benefit post mastectomy.

Timing post radiotherapy

·  more than 6 months post radiotherapy is recommended to overcome the acute effects of radiotheraoy skin changes (PRS CME 2001)

Complications of radiotherapy to the breast and chest wall

Early

1.  Skin desquamation, necrosis

2.  Increased risk of infections

Late

1.  Skin pigmentation changes, atrophy, fibrosis, telangiectasias

2.  Breast necrosis

3.  Osteoradionecrosis

4.  Cardiac disease

a.  pericardial disease, myocardial disease, coronary artery disease, valvular defects, and conduction abnormalities

b.  higher incidence of mortality from coronary artery disease post chest wall irradiation

5.  Pulmonary fibrosis

6.  Brachial plexitis

7.  Lymphoedema

a.  Risk of lymphagiosarcona (Stewart Treeves syndrome)

8.  Secondary tumour induction

a.  Commonly cutaneous angiosarcoma

Effect of Radiotherapy on Immediate Breast Reconstruction

Reviews

(Javaid M; Radiation effects on the cosmetic outcomes of immediate and delayed autologous breast reconstruction: an argument about timing. J Plast Reconstr Aesthet Surg. 2006)

·  a systematic review to gather the available evidence on the optimum timing of the radiotherapy in relation to autologous breast reconstruction

·  no randomised controlled trial on this topic

·  overall incidence of complications was increased in patients with radiotherapy in three out of four studies for autologous breast reconstruction

·  Despite the paucity of the published data, the current evidence suggests that the radiation has a deleterious effect on autologous flap reconstruction.

·  Delayed reconstruction seems to be a safe option in most of the cases.

Pedicled TRAM flap

Williams, Bostwick: The Effects of Radiation Treatment after TRAM Flap Breast Reconstruction PRS Oct 1997

·  19 patients who received radiation therapy after pedicled TRAM flap reconstruction compared with 108 patients who received radiation prior to reconstruction and 572 patients who underwent breast reconstruction without radiation.

·  Total complications similar but nature of the complication changes (instead of fat necrosis, radiotherapy caused breast distorting fibrosis).

·  52% demonstrated postradiation changes in the TRAM flap and 31% required revision

Spears SL; Ducic I; The effect of radiation on pedicled TRAM flap breast reconstruction: outcomes and implications. Plast Reconstr Surg. 2005 Jan

·  Post-TRAM radiation patients were compared with patients who received pre-TRAM radiation and a control TRAM-only group who received no radiation.

·  for aesthetic outcome, symmetry, and contracture; control > irradiated prereconstruction patients> irradiated postreconstruction patients

·  Neither preoperative nor postoperative radiation increased the risk for flap or donor-site complications.

Free TRAM

Tran N, Chang D; Comparison of Immediate and Delayed Free TRAM Flap Breast Reconstruction in Patients Receiving Postmastectomy Radiation Therapy. PRS July 2001

·  32 immediate TRAM flap reconstruction sbefore radiation therapy and 70 patients had radiation therapy before TRAM flap reconstruction

·  incidence of early complications did not differ significantly between the two groups

·  incidence of late complications was significantly higher in the immediate reconstruction group than in the delayed reconstruction group (87.5 percent versus 8.6 percent).

·  Nine patients (28 percent) in the immediate reconstruction group required an additional flap to correct the distorted contour from flap shrinkage and severe flap contraction.

·  Flap distortion with radiation

o  Worsens with time

o  flap will displace superiorly, and the appearance will resemble that of a contracted implant reconstruction to untrained examiners

Implant only reconstruction

·  Radiation following implant reconstruction leads to higher extrusion rates and increased capsular contracture (Spear PRS 2000)

·  incidence of complication in the radiated group was significantly higher than within the control group.

1.  more symptomatic contractures 32.5% vs 0%

2.  more likely to need salvage flaps 27% vs 2.5%

3.  aesthetic appeareances marginally better in the control group

·  Spears recommends that latissimus dorsi should not be used for immediate reconstruction if radiotherapy is planned as it is an excellent solution for the post-irradiated distorted breast

·  At Memorial Sloan Kettering, Cordiero has not found any significant differences in complications but he uses a stringent protocol – expansion commenced 2 weeks post-op and continued during chemo. Exchanged for implant 4 weeks after chemo and radiation applied 4 weeks post exchange

Summary

·  The breast reconstruction literature consistently indicates that attempts to expand irradiated chest wall skin result in frequent complications and poor aesthetic results. The only indication for use is with bilateral reconstructions undergoing bilateral irradiation (Cordiero writes that cosmetic result is acceptable even with unilateral irradiation – PRS Nov 2005).

·  Autologous tissue reconstruction after radiation therapy is much safer and produces a much superior aesthetic outcome

·  Immediate reconstruction offers the best aesthetic outcomes if postmastectomy radiation therapy is not needed, but if postmastectomy radiation therapy is required, delayed reconstruction is preferable to avoid potential aesthetic and radiation-delivery problems

·  For immediate cases requiring radiotherapy, autologous tissues have less complications than expander reconstruction

·  Flap/donor ischaemic complications are not increased

·  Late aesthetic complications are increased

Effect of Breast Reconstruction on Radiotherapy

MD Anderson Radio-oncology unit (Am J Clin Oncol Oct 2005)

·  Immediate breast reconstruction imposed significant modification of postmastectomy radiotherapy techniques

·  included an inability to cover the ipsilateral IMC region , inadequate chest wall breadth coverage medially and/or laterally, and an excess volume of lung within the treatment field

·  Reconstruction included TRAM, lat dorsi + expander and expander only

Choice of Recipient Vessels in Delayed TRAM Breast Reconstruction after Radiotherapy

Temple, C; PRS Jan 2005

·  123 planned free TRAM flaps, 106 were successfully executed as microsurgical transfers - 14% converted to pedicled flaps due to unusable vessels

·  thoracodorsal vessel unusability rate – 26%

o  most common reason for rejection was heavy scarring

·  internal mammary vessel unusability rate – 20%

o  did not differ between the right and left sides of the chest.

o  most common reason for rejection of the internal mammary vessels as recipients was a small vein.

·  Multivariate analysis revealed a trend for higher complication rates in smokers and with the use of the thoracodorsal vessels as the recipients. - total flap loss, vascular complications, and upper extremity lymphedema were somewhat more prominent when thoracodorsal vessels were used, but not significantly so

·  Overall, no discernible unusability or outcome differences were detected between the internal mammary and thoracodorsal groups.

Safety of NAC reconstruction post radiotherapy

·  Studies suggest that NAC reconstruction post autologous irradiated reconstruction is safe

·  Cordiero (Ann Plast Surg Jul 05) on NAC recon after expanded only reconstruction and irradiated breasts

o  Poor outcome predicted by a history of delayed healing or necrosis of the mastectomy flaps, thin mastectomy skin flaps, a history of infection at the surgical site and especially those with moderate to severe late radiation changes of the mastectomy flap skin indicate poor surgical candidates.

o  25% complication rate including 1 total nipple loss followed by implant exposure and removal