Radiotherapy and the management of the axilla in early breast cancer

[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.

Radiotherapy for stage II and stage III breast cancer patients with negative lymph nodes after preoperative chemotherapy and mastectomy

PURPOSE

To evaluate the effect of postmastectomy radiotherapy (PMRT) in Stage II-III breast cancer patients with negative lymph nodes (pN0) after neoadjuvant chemotherapy (NAC).

PATIENTS AND MATERIALS

Of 1,054 breast cancer patients treated with NAC at our institution between 1990 and 2004, 134 had pN0 status after NAC and mastectomy. The demographic data, tumor characteristics, metastatic sites, and treatments were prospectively recorded. The effect of PMRT on locoregional recurrence-free survival and overall survival (OS) was evaluated by multivariate analysis, including known prognostic factors.

RESULTS

Of the 134 eligible patients, 78 (58.2%) received PMRT and 56 (41.8%) did not. At a median follow-up time of 91.4 months, the 5-year locoregional recurrence-free survival and OS rate was 96.2% and 88.3% with PMRT and 92.5% and 94.3% without PMRT, respectively (p = NS). The corresponding values at 10 years were 96.2% and 77.2% with PMRT and 86.8% and 87.7% without PMRT (p = NS). On multivariate analysis, PMRT had no effect on either locoregional recurrence-free survival (hazard ratio, 0.37; 95% confidence interval, 0.09-1.61; p = .18) or OS (hazard ratio, 2.06; 95% confidence interval, 0.71-6; p = .18). This remained true in the subgroups of patients with clinical Stage II or Stage III disease at diagnosis. A trend was seen toward poorer OS among patients who had not had a pathologic complete in-breast tumor response after NAC (hazard ratio, 6.65; 95% confidence interval, 0.82-54.12; p = .076).

CONCLUSIONS

The results from the present retrospective study showed no increase in the risk of distant metastasis, locoregional recurrence, or death when PMRT was omitted in breast cancer patients with pN0 status after NAC and mastectomy. Whether the omission of PMRT is acceptable for these patients should be addressed prospectively.

[Role of lymph node irradiation in breast cancer patients with negative pathologic node status after neoadjuvant chemotherapy: the René-Huguenin Cancer Center experience]

PURPOSE

Neoadjuvant chemotherapy generally induces significant changes in the pathological extent of disease. This potential down-staging challenges the standard indications of adjuvant radiation therapy. We assessed the utility of lymph node irradiation in breast cancer patients with pathological N0 status (pN0) after neoadjuvant chemotherapy and breast-conserving surgery.

PATIENTS AND MATERIALS

Among 1054 breast cancer patients treated with neoadjuvant chemotherapy in our institution between 1990 and 2004, 248 patients with clinical N0 or N1-N2 lymph node status at diagnosis had pN0 status after neoadjuvant chemotherapy and breast-conserving surgery. Cox regression analysis was used to identify factors influencing locoregional recurrence-free survival, disease-free survival and overall survival.

RESULTS

All 248 patients received breast irradiation, and 158 patients (63.7%) also received lymph node irradiation. With a median follow-up of 88 months, the 5-year locoregional recurrence-free survival and overall survival rates were respectively 89.4% and 88.7% with lymph node irradiation and 86.2% and 92% without lymph node irradiation (no significant difference). Survival was poorer among patients who did not have a pathological complete primary tumor response (pCR) (hazards ratio [HR]=3.05; 95% CI, 1.17 to 7.99) and in patients with N1-N2 clinical status at diagnosis ([HR]=2.24; 95% CI, 1.15 to 4.36). Lymph node irradiation did not significantly affect survival.

CONCLUSIONS

Relative to combined breast and local lymph node irradiation, isolated breast irradiation does not appear to be associated with a higher risk of locoregional relapse or death among breast cancer patients with pN0 status after neoadjuvant chemotherapy. These results need to be confirmed in a prospective study.

Lymphatic endothelial cells, lymphedematous lymphangiogenesis, and molecular control of edema formation

Lymphedema, defined as the abnormal accumulation of protein-rich fluid in soft tissues, results from the dysfunction of lymphatic system, an imbalance between lymph formation and its absorption into the initial lymphatics. Primary lymphedema occurs rarely on idiopathic or developmental abnormalities, especially hypoplasia or aplasia of lymphatics. Secondary lymphedema commonly develops when lymph transport is impaired due to lymphatic damage or resection of lymph nodes in surgery, infection, and radiation. Lymphatic endothelial cells (LECs) actively participate in the phenotypic consequences of a deranged lymphangiogenesis relating to tissue fluid accumulation in the pathogenesis of lymphedema. Recent insights into molecular genetic bases have shown an updated genotype-phenotype correlation between lymphangiogenesis, lymphatic function, and lymphedema. FOXC2, EphrinB2, VEGFR-3, VEGF-C, angiopoietin-2, Prox-1 and podoplanin have proved to be important factors of the genetic cascade linking to hereditary lymphedema, and embryonic and postnatal lymphatic development. FOXC2 may have a key role in regulating interactions between LECs and smooth muscle cells, and in the morphogenesis of lymphatic valves. Reduced VEGFR-3 tyrosine kinase activity and subsequent failure in transducing sufficient physiological VEGF-C/-D signals may affect LEC function and structure in the intercellular junctions and peri-lymphatic components. Identification of genetic markers in humans and animal models would facilitate the management of environmental factors influencing the expression and severity of lymphedema, and provide a basis for developing novel targeted therapies for the disease.

Breast cancer: improving outcome following adjuvant radiotherapy

In the treatment of early breast cancer adjuvant irradiation improves local control following both mastectomy and breast-conserving surgery. For women at high risk of relapse it also increases survival. Breast radiotherapy is usually given using simple planning techniques and serious morbidity is unusual. The greatest concern following adjuvant breast irradiation is of an increase in cardiovascular mortality after 15-20 years. New techniques of breast irradiation including conformal radiotherapy and intensity-modulated radiotherapy (IMRT) have been shown to reduce cardiac and lung irradiation. In addition, improved dosimetry within the breast may improve both local control and cosmesis. To replace current radiotherapy techniques with those requiring more complex planning would demand an increase in resources including both machinery and staff. In this review we outline the indications and benefits of breast radiotherapy along with the planning process. Technical advances are discussed within the context of improving outcome at a time of limited national resources.

Risk factors for regional nodal failure after breast-conserving therapy: regional nodal irradiation reduces rate of axillary failure in patients with four or more positive lymph nodes

PURPOSE

To determine the incidence of, and risk factors for, regional nodal failure (RNF) and to evaluate the effectiveness of, and indications for, regional nodal irradiation (RNI) in patients with Stage I-II breast cancer treated with breast-conserving therapy.

METHOD AND MATERIALS

A total of 1500 cases of Stage I-II breast cancer were treated with breast-conserving therapy between February 1980 and December 2000. All patients underwent excisional biopsy, and 925 (62%) underwent re-excision. Level I-II axillary lymph node dissection was done in 94% of patients. The lymph nodes were pathologically involved in 335 patients (22%); 255 with 1-3 nodes and 80 with >/=4 nodes involved. All patients received whole breast irradiation to a median dose of 45 Gy, and 97% received a tumor bed boost to a median dose of 61 Gy. Treatment included the breast only in 1309 patients (87%), and the breast and regional lymphatics in 191 (13%).

RESULTS

With a median follow-up of 8.1 years, 35 patients had failure within the regional nodes: 12 patients (6%) who received RNI and 23 patients (2%) who did not. The 5- and 10-year rate for any RNF was 1.9% and 2.8%, respectively. The 5 and 10-year rates of axillary failure and supraclavicular failure were 0.6% and 1.0% and 0.9% and 1.6%, respectively. In patients with >/=4 positive lymph nodes, RNI reduced the 10-year rate of any RNF from 11% to 2% (p = 0.024), the rate of axillary failure from 5% to 0% (p = 0.019), and the rate of supraclavicular failure from 11% to 2% (p = 0.114). RNI did not affect the rate of axillary failure or supraclavicular failure in patients with 1-3 positive nodes. In node-negative patients, the rate of RNF was significantly greater if <6 nodes were removed at the time of axillary dissection. Multiple clinical, pathologic, and treatment-related factors were analyzed for association with RNF. On univariate analysis, RNF was associated with the number of nodes excised, number of positive nodes, percentage of positive nodes, size of nodal metastasis, presence of angiolymphatic invasion, estrogen receptor status, age, systemic chemotherapy, and RNI. Three subsets of patients had unusually high rates of RNF, those with >/=67% nodes positive (16%), nodal metastasis >/=2.0 cm (44%), or age </=35 years (14%). On multivariate analysis, the only significant predictor of RNF was the maximal size of the nodal metastasis. RNI did not improve the overall survival for any subset of patients. The number of lymph nodes excised had an impact on overall survival, with a 10-year survival rate of 33%, 65%, and 69% in patients with <6, 6-10, and >10 nodes excised, respectively (p = 0.05).

CONCLUSION

Failure within the regional lymph nodes as an isolated site of first relapse is uncommon in patients with Stage I-II breast cancer treated with breast-conserving therapy. RNI can significantly reduce the rate of RNF (axillary failure) in patients with >/=4 positive lymph nodes. The maximal size of the lymph node metastasis was found to be the only significant independent predictor of RNF, with nodal metastases >/=2.0 cm associated with extremely high regional failure rates. Despite this, young age and the extent of axillary dissection (particularly as related to the number of positive nodes) also appear to be important and should be considered when evaluating patients for RNI. Inadequate axillary dissection was not only associated with increased regional failure, but also reduced survival.

Prognostic factors for lymphedema after primary treatment of breast carcinoma

BACKGROUND

Lymphedema of the arm is a serious consequence of breast carcinoma treatment. Postmastectomy lymphedema of the upper limb usually is related to certain risk factors such as axillary surgery, radiotherapy, obesity, venous outflow obstruction, delayed wound healing, and infection. The objective of the current study was to identify the risk factors for secondary lymphedema after breast carcinoma treatment.

METHODS

A total of 1278 breast carcinoma patients, all of whom were residents of Florence area, Italy at the time of diagnosis and who were operated on by the same surgeon between 1989 and 1997, were included in the current analysis. The circumference of the upper arm was measured and lymphedema was defined as being present when an increase of > 5% of the sum differences between the two arms was found. The observed cumulative probability of lymphedema occurrence was estimated using the Kaplan-Meier method. The Cox proportional hazards models were fitted to assess the relative excess risk of lymphedema and to check for confusing factors. All patients with lymphedema who were living in the Florence area were referred to a specialist for treatment.

RESULTS

Two hundred three cases of lymphedema of the ipsilateral arm were found (15.9%). The right arm was affected in 44.5% of the cases and the left arm in 55.5%. The risk of developing late lymphedema was found to be significantly related to a pathologic T2 classification (hazards ratio [HR] = 1.44; 95% confidence interval [95% CI], 1.06-1.94) and postoperative radiotherapy (HR = 1.35; 95%CI, 1.00-1.83). Patients who had > 30 lymph nodes removed were found to have a borderline increased risk of lymphedema (HR = 1.64; 95% CI, 0.99-2.74). Multivariate analysis identified postoperative radiotherapy (HR = 1.38; 95% CI, 1.02-1.86) and the number of lymph nodes removed (HR = 1.29; 95% CI, 1.04-1.59) to be independent predictors of lymphedema.

CONCLUSIONS

The results of the current study demonstrated that the risk of lymphedema was correlated with the use of postoperative radiotherapy and the number of lymph nodes removed.

Adjuvant radiotherapy in breast cancer--the treatment of lymph node areas

Adjuvant radiotherapy decreases the risk of locoregional recurrences threefold, according to the results of many randomized trials and overviews. In patients treated with total mastectomy, the risk of local recurrence is mainly related to the number of involved axillary nodes, i.e. about 25%, 35% and 55% at 10 years when 1-3, 4-9 and 10 or more nodes are involved, respectively. In contrast, at 10 years, less than 15% of patients with negative axillary nodes relapse locally. The effect of adjuvant radiotherapy on distant metastases and overall survival is a controversial issue. On the one hand, recent results are compatible with the existence of a mechanism of secondary dissemination generated from locoregional tumor nests. The beneficial effect of radiotherapy can be observed whether with or without adjuvant systemic treatment. On the other hand, a deleterious late toxic effect, mainly cardiac, has also been shown. The importance of improvements in radiation techniques and quality assurance to obtain a positive balance in terms of overall survival is emphasized.

Management of the axilla in primary breast cancer

Treatment of the axilla with either radiotherapy or surgery remains an integral part of the management of patients with invasive breast cancer. In general, the standard treatment of the axilla involves a partial ALND (surgical clearance of axillary nodes from levels I and II). There is as yet no evidence that axillary treatment improves survival, but the issue remains controversial. Axillary lymph node dissection is an effective staging procedure and is essential for local control of disease in the axilla, although, with increased emphasis on mammographic screening and early detection, the incidence of node-positive breast cancers is decreasing. Today, only about 30% to 40% of all invasive breast cancers are node-positive. Thus, in most cases, the potential morbidity of ALND could be avoided if the status of the axillary nodes were ascertained with a less invasive procedure. The SLNB may eventually prove to be a preferred alternative to routine ALND. It must first be demonstrated, however, that SLNB (without completion ALND) does not adversely affect outcome. Randomized controlled trials must address these concerns, and surgeons must await completion of these studies before accepting SLNB as the standard of care.

Postmastectomy radiotherapy: randomized trials

Postmastectomy radiotherapy decreases threefold the risk of locoregional recurrences according to the results of many randomized trials and overviews. This risk is mainly related to the number of involved axillary nodes (ie, about 25%, 35%, and 55% at 10 years when 1 to 3, 4 to 9, and 10 or more nodes are involved). In contrast, at 10 years, fewer than 15% of patients with negative axillary nodes relapse locally. The effect of postmastectomy radiotherapy on distant metastases and overall survival is a controversial issue. On the one hand, results are compatible with the existence of a mechanism of secondary dissemination generated from locoregional tumor nests. The beneficial effect of radiotherapy may be observed in the absence or presence of adjuvant systemic treatment. On the other hand, a deleterious late toxic, mainly cardiac, effect of radiation has also been shown. This point emphasizes the importance of radiation technique and quality to obtain a positive balance in terms of overall survival.

Axillary lymph node involvement in stage III breast cancer: treatment implications

BACKGROUND AND OBJECTIVES

The introduction of multimodal therapy has improved the prognosis in stage III breast cancer. A knowledge of the likely axillary lymph node status at presentation is important, both to plan surgical therapy to the axilla and to establish the effect of induction therapy on the axillary nodes.

METHODS

The study involved a chart review of 114 patients with stage III breast cancer who were treated by modified radical mastectomy without prior systemic therapy. A standard method was used for axillary dissection and numbers and levels of pathologically involved lymph nodes were recorded. The incidence of lymph node metastases was correlated with tumour size, grade, and clinical T stage. The accuracy of clinical axillary staging and the relationship between level III invasion and the number of level I and II nodes invaded was also assessed.

RESULTS

Overall, 96 of 114 (84%) patients had axillary nodal metastases, and 37 of 114 (32%) patients had level III metastases. Eighteen of 43 tumours (42%) 30 mm or less had level III metastases and 27% of larger tumours had level III metastases (6/25 31-49-mm tumours, and 12/42 50+-mm tumours). Of 98 gradable cancers, only 1 out of 10 well-differentiated tumours had level III metastases, but the rate in moderately and poorly differentiated tumours was 36% (19/53) and 37% (13/35), respectively. Clinical node staging was unreliable. A group of patients with a low likelihood of level III metastases who might benefit from an axillary procedure less than level III dissection could not be identified preoperatively.

CONCLUSIONS

Patients with stage III breast cancer have a high incidence of level III axillary lymph node metastases. A subgroup with a low incidence of level III metastases could not be identified in this study. Until axillary downstaging has been convincingly demonstrated with induction therapy, a less than complete axillary procedure may leave the patient at high risk of axillary relapse.

Shoulder movement after the treatment of early stage breast cancer

At 18 months after surgery and post-operative radiotherapy, the function of the ipsilateral shoulder joint was assessed both subjectively and objectively in 141 patients with early stage breast cancer. Half of the patients said that function was reduced compared with before (any) treatment. Overall, 48% had measured limitation of at least one shoulder movement. Mastectomy patients had more problems than those who had a wide local excision (79% versus 35%) as did those (node positive patients) who had axillary irradiation (73%) compared with those who did not (35%). Patients with dysfunction of shoulder movement before radiotherapy had a 60% chance of persistent movement problems at 18 months, compared with 24% of those with normal postoperative function. Informal exercise did not appear to have had any impact on the development of movement limitation.

Modern trends in breast cancer therapy: towards less lymphoedema?

AIMS

To review from the evidence, with special reference to axillary node management, whether the incidence of lymphoedema following breast cancer treatment is falling in modern breast practice.

CONCLUSIONS

The incidence of lymphoedema does seem to be reducing with modern approaches to breast cancer management. Axillary treatment seems to determine its development but more studies looking specifically at this problem are needed.

The role of regional nodal irradiation in the management of patients with early-stage breast cancer treated with breast-conserving therapy

PURPOSE

To determine the incidence of regional nodal failure (RNF) and indications for regional nodal irradiation (RNI) in patients with Stage I and II breast cancer treated with breast-conserving therapy (BCT).

METHODS AND MATERIALS

Four hundred fifty-six patients with Stage I/II breast cancer were treated with BCT at William Beaumont Hospital. All patients underwent excisional biopsy and 288 (63%) were reexcised. A Level I/II ipsilateral axillary lymph node dissection was performed on 431 patients (95%). Pathologically involved nodes were found in 106 (23%) cases (69 with one to three nodes and 37 with > or = four nodes involved). All patients received whole breast irradiation (median dose 50 Gy) and 415 (91%) were boosted to the tumor bed (median total dose 60.4 Gy). Three hundred and sixty (79%) patients received breast alone irradiation and 96 (21%) also received RNI. The median axilla/supraclavicular fossa dose was 50 Gy.

RESULTS

With a median follow-up of 83 months, 15 patients developed a RNF for a 5- and 8-year actuarial rate of 3 and 4%, respectively. The 5- and 8-year actuarial rates of axillary failure (AF) were 0.7 and 1.0%, respectively. The incidence of RNF or AF was not affected by the use of RNI in N0 or N1 patients with one to three positive nodes. Only in patients with four or more positive nodes was there a trend towards improved regional control with RNI (p = 0.09). However, patient numbers were extremely small, and this improvement was limited to a reduction in the rate of failure in the supraclavicular fossa (SCF) (20 vs. 0%, p = 0.04). Multiple clinical, pathologic, and treatment related factors were analyzed for an association with AF. On univariate analysis, AF was associated with the number of lymph nodes excised (p < 0.0001) estrogen receptor status (p = 0.0016), and pathologic node status (p = 0.0021).

CONCLUSIONS

Regional nodal failure as the first site of failure is uncommon in patients with early-stage breast cancer treated with BCT with < or = three positive lymph nodes and appears unaffected by RNI. For patients with four or more positive lymph nodes, a trend towards improved RNF was noted with RNI, primarily in the SCF. However, patient numbers were extremely small in all subsets analyzed. Additional studies are needed to further define the need for RNI in these patients and help determine other factors associated with RNF.

The increasing efficacy of breast cancer treatment

Breast cancer is the commonest malignancy in women and although identification of this multi-system disease has increased, the survival rates have not dramatically altered over the past four decades. Optimium treatment of patients with breast cancer is a subject of great debate and traditionally may be divided into surgery, radiotherapy, chemotherapy and hormone manipulation. Halsted's radical mastectomy, although initially superseded by more mutilating surgery involving removal of tumour, breast, pectoral muscles and axillary contents, has given way to more conservative surgery and breast conservation, so now removal of the tumour with a marginal of healthy tissue is possible. Additional loco-regional radiotherapy has added to the increasing number of treatment options available to both doctor and patient. Systemic adjuvant therapy, primarily hormonal therapy, is used with the aim of decreasing the incidence of recurrence and distant tumour development. Through the process of randomized controlled trials these new therapeutic treatments have shown to be effective in the treatment of locoregional disease. Surgery in patients with advanced systemic disease is limited, however radiotherapy is of considerable importance and can be used to treat or palliate sites of metastases. In recent years trials have assessed chemotherapeutic regimens. However, limited number of patients and adequate randomization have hindered the confident acceptance of these results. Cyclophosphamide, methotrexate and 5 fluorouracil still remain the standard chemotherapeutic regimen, however many new drugs are currently undergoing trials and these or combinations of these may prove to be of future clinical use. Dramatic advances in cell and molecular biology have allowed the development of novel breast cancer therapies. Specific oncogenes and loss of tumour suppressor genes have been associated with decrease patient survival, with the presence of lymph node metastases and with decreased relapse free survival. Growth factor receptor blockers and tyrosine kinase inhibitors may be developed to specifically eradicate breast cancer cells. Immunotherapy and gene therapy may produce effective therapies. Trials utilizing cytokines and trials increasing the immunogenicity of tumours have already reported promising results. Surgery, chemotherapy, radiotherapy and hormone manipulation are the major treatment arms of breast cancer therapy. However, breast cancer still accounts for 20 percent of all female cancer deaths and the overall survival of patients has remained relatively static over the past forty years. From our increasing understanding of the pathological processes involved in the development and spread of breast cancer, new pharmaceutical, immunological and gene therapies may dramatically increase the cure rate of this serious disease.

Axillary lymph nodes and breast cancer: a review

BACKGROUND

The value of surgical staging and treatment of the axillary lymph nodes with either surgery or radiotherapy in the initial management of patients with Stage I or II invasive breast cancer is controversial.

METHODS

A review of retrospective and prospective clinical studies was performed to assess the risks of axillary lymph node involvement and the effectiveness and morbidity of various treatment options.

RESULTS

The risk of axillary lymph node involvement is substantial for most patients, even those with small tumors. The morbidity resulting from a careful Level I/II axillary dissection or moderate-dose axillary radiotherapy is limited. Such treatment is highly effective in preventing axillary recurrence. The symptoms resulting from axillary failure can be controlled in many, but not all, patients. The available data suggest, but do not prove, that the initial use of effective axillary treatment may result in a small improvement in long term outcome in some patient subgroups.

CONCLUSIONS

Most patients should be treated with either axillary surgery or irradiation. Highly selected subgroups of patients may have such low risks of involvement that specific axillary treatment is of little value. However, such subgroups have not yet been well defined. Treatment approaches that do not involve specific axillary treatment should be considered investigational at present, and the patients should be informed as to their potential risks. Prospective clinical studies of these issues should be pursued.