The importance of locoregional control in the treatment of breast cancer and its impact on survival

Sustained and Localized Drug Depot Release Using Radiation-Activated Scintillating Nanoparticles

Clinical treatment of cancer commonly incorporates X-ray radiation therapy (XRT), and developing spatially precise radiation-activatable drug delivery strategies may improve XRT efficacy while limiting off-target toxicities associated with systemically administered drugs. Nevertheless, achieving this has been challenging thus far because strategies typically rely on radical species with short lifespans, and the inherent nature of hypoxic and acidic tumor microenvironments may encourage spatially heterogeneous effects. It is hypothesized that the challenge could be bypassed by using scintillating nanoparticles that emit light upon X-ray absorption, locally forming therapeutic drug depots in tumor tissues. Thus a nanoparticle platform (Scintillating nanoparticle Drug Depot; SciDD) that enables the local release of cytotoxic payloads only after activation by XRT is developed, thereby limiting off-target toxicity. As a proof-of-principle, SciDD is used to deliver a microtubule-destabilizing payload MMAE (monomethyl auristatin E). With as little as a 2 Gy local irradiation to tumors, MMAE payloads are released effectively to kill tumor cells. XRT-mediated drug release is demonstrated in multiple mouse cancer models and showed efficacy over XRT alone (p < 0.0001). This work shows that SciDD can act as a local drug depot with spatiotemporally controlled release of cancer therapeutics.

Management of operable invasive breast cancer in women over the age of 70: long-term results of a large-scale single-institution experience

BACKGROUND

The treatment of choice for elderly women with breast cancer remains controversial. This retrospective analysis of a cohort from a single institution was designed to evaluate whether such patients are really undertreated because of their age and to reappraise their usual management.

METHODS

The characteristics of 538 patients aged > or = 70 years with operable breast cancer, treated between 1995 and 1999, were retrospectively analyzed comparing patients aged 70 to 75 years (group I, n = 288), 75 to 80 years (group II, n = 156), and > or = 80 years (group III, n = 94). Cause-specific survival, distant recurrence-free interval, and local control were estimated by the Kaplan-Meier method and compared by log rank test. Multivariate analysis used Cox regression.

RESULTS

In group III, tumors were more frequently T2 than T1 (P < 0.0001) and estrogen receptor negative (P = 0.045) than in groups I and II. Surgery was performed in 94.6% of patients, breast-conserving in 72.1% (62% in group III; P = 0.0015) with axillary dissection in 89.2% (77% in group III; P = 0.0015); 100% received radiotherapy after lumpectomy (hypofractionated in 63% of group III; P < 0.0001). Adjuvant hormone therapy and chemotherapy were administered to 57 and 3.7% of patients, respectively. At 7 years, no difference in the three groups was observed for cause-specific survival (91% for group I, 89% for group II, 86% for group III) distant recurrence-free interval, and local control (>90%).

CONCLUSIONS

Elderly patients with operable breast cancer who are completely and correctly treated with realistic treatment options that are based on surgery and adjuvant radiotherapy have a similar chance of being cured as younger patients.

Local relapse after breast-conserving surgery and radiotherapy: effects on survival parameters

PURPOSE

This retrospective analysis of 1,610 women treated for breast cancer and 88 patients with local relapse aims to show the poor survival parameters after local failure and to evaluate risk factors and compare them with other studies and analyses published.

PATIENTS AND METHODS

Between 1984 and 1997, 1,610 patients presenting with a total of 1,635 pT1-2 invasive and noninvasive carcinomas of the breast were treated at the authors' institution. The mean age was 57.1 years (range 25-85 years). Treatment protocols involved breast-conserving surgery with or without systemic therapy and whole-breast radiotherapy in all women, followed by a boost dose to the tumor bed according to risk factors for local recurrence. All axillary node-positive patients underwent systemic therapy (six cycles of classic CMF or tamoxifen 20 mg/day for 2-5 years). The time of diagnosis of local relapse was defined as time 0 for the survival curves after local failure. The association of clinicopathologic factors was studied using uni- and multivariate analyses. Survival and local control were calculated by the Kaplan-Meier actuarial method and significance by the log-rank test.

RESULTS

After a mean follow-up of 104 months, 88 local failures were recorded (5.4%). Calculated from the time of diagnosis of local relapse, 5-year overall survival (OS) was 62.8%, metastasis-free survival 60.6%, and disease-specific survival 64.2%. In patients with failure during the first 5 years after treatment, the survival parameters were worse (OS 50.6%) compared to those who relapsed after 5 years (OS 78.8%; p < 0.028). Significances were also found for initial T- and N-stage and type of failure (solid tumor vs. diffuse spread).

CONCLUSION

This analysis again shows that the survival parameters are worsening after local relapse, especially in case of early occurrence. In breast cancer treatment, therefore, the goal remains to avoid local failure.

The incidence, indications and outcome for the non-operative management of breast cancer

BACKGROUND AND OBJECTIVES

This study aimed to identify the proportion of patients with breast cancer who do not undergo primary operative treatment, to identify the reasons surgery is not performed, and to determine the outcome for this group of patients.

METHODS

Data was obtained from the Bedford Breast Cancer Registry for all non-metastatic patients presenting between January 1990 and December 2004 who were initially treated non-operatively. Robust diagnostic, therapeutic, and follow-up data on all patients was collected prospectively during this period.

RESULTS

One hundred and eighty-five out of 2110 episodes of breast cancer were treated non-operatively during this period. Sixty-eight percent of patients were unfit for surgery, 15% had inoperable tumours, and 17% refused surgical intervention. Median survival and 5-year survival rate for all non-operative patients were 3.7 years and 41.2%. Median survival for inoperable patients was 3.7 years, compared with 3.5 years for those unfit for surgery and 4.2 years for those who refused surgery. The 5-year survival rate for patients refusing surgery was 43%, compared with 61% for a matched group of patients undergoing standard surgical therapy.

CONCLUSIONS

This study provides useful data on the reasons for, and outcome of, the non-operative management of breast cancer.

The process of metastasisation for breast cancer

To investigate the process of metastasis, primary clinical data and disease events such as metastases, local recurrence and survival (median follow-up 9.4 years) from the Munich Cancer Registry from 1978 to 1996 were analysed. Since metastases, even from small tumours, may be initiated before the diagnosis of the primary tumour, the growth of the primary tumour and metastasisation may be two autonomous processes. In our data, survival following metastases was almost unrelated to primary tumour size. However, the number of M1 cases and the time to metastasisation depended on the tumour diameter at diagnosis. The time from initiation of metastases to its diagnosis was estimated as 5.8 years. The growth of metastases was almost homogeneous. However, the growth time following metastasisation-depending on the metastases-free time, receptor status and histological grade-only varied by approximately a factor of 2. Local recurrence, above all, was an indicator of metastases. Furthermore, local recurrence may also have the potential to metastasise. Excess mortality due to local recurrence was estimated up to 9.3 years after diagnosis. Our hypothesised metastases model illustrates the importance of early detection, the concept of breast-conserving therapy and additional metastases from local recurrence. It highlights the benefits of optimal local therapy of the primary tumour and the limitations of systemic therapy. It also questions the use of axilla dissection and lymph node irradiation. Its generalisation to solid tumours may help to clarify many of the current controversial debates.

The importance of quality assurance in surgical oncology

AIMS

The aims were to review the existing methods of quality assurance in surgical oncology and to determine a relationship between surgery-related factors and the variety in outcomes in the treatment of solid cancers.

METHODS

The literature was reviewed by searching Medline and Cancerlit databases.

RESULTS

Wide variations were found in virtually all tumour types. Clear evidence was found that an improvement in the quality of the surgical procedure could have major implications for the prognosis and quality of life of cancer patients.

CONCLUSIONS

These findings emphasize the need for strict quality control procedures in surgical oncology and might imply a considerable change in cancer treatment strategies, because the routine use of adjuvant therapies could be questioned.

Excellent response to gemcitabine in a massively pre-treated woman with extensive cutaneous involvement after recurrence of breast cancer

A 50-year-old woman presented with local relapse of breast cancer 6 years after partial mastectomy. Relapse was accompanied by extended skin induration due to tumor cell embolization of dermal lymphatics. During the following years the patient was exposed to 11 different anti-tumor regimens including 13 cytotoxic drugs (including alkylating agents, antitumor antibiotics, vinca alcaloids, epipodophyllotoxins, and taxanes), 4 anti-hormonal, and 2 immunologic attempts. Paclitaxel achieved a prolonged local improvement for some 7 months, but further various treatments were ineffective. At that time gemcitabine therapy was initiated and tumor infiltration of the skin was visibly diminished only 2 weeks later. After that tumor regressed further for 5 months and remained stable with continued doses of gemcitabine during much of the woman's last year. The patient died of acute myeloid leukemia (AML) 4 years after the local recurrence of breast cancer. Since multiple treatments using a plethora of aggressive cytotoxic drugs may render several classes of chemotherapy agents ineffective due to cross-resistance, it seems advisable to select mild agents that are not subject to multidrug resistance mechanisms and display a unique mode of action as demonstrated in this case by gemcitabine.

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.

The natural history of breast cancer

The natural history of breast cancer has not been fully elucidated, but physicians are making progress in the treatment of patients with this disease. Randomized, controlled trials indicate that screening, adjuvant systemic therapy, and adjuvant radiotherapy can reduce the risk for death caused by breast cancer. More importantly, national statistics show that breast cancer death rates are now decreasing (after remaining stagnant for nearly 40 years), but additional investigation into the natural history of breast cancer is clearly warranted. The randomized controlled trials on screening and local therapy, in particular, provide important insights into the natural history of the disease. Thus, the results of these trials should serve as a basis for additional investigation. Ultimately, a better understanding of the natural history of breast cancer may translate into improved treatments and better outcomes.

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.

Adjuvant therapy of breast cancer--an overview

Adjuvant therapy in the treatment of breast cancer commonly refers to therapies that supplement primary treatment, traditionally mastectomy and, more recently, breast-conserving surgery. The present paper examines the evolution of systemic therapies and radiotherapy in their role as adjuvants to mastectomy, and offers a brief description of current treatment regimens for early and locally advanced disease.

[Influence of locoregional irradiation on local control and survival in breast cancer]

Locoregional control is a crucial step in the achievement of breast cancer cure. In ductal carcinoma in situ, breast irradiation significantly reduces the rates of local recurrence whatever the histological subtypes, as demonstrated by the NSABP-B17 trial (25.8% of local recurrences without radiotherapy vs. 11.4% with radiotherapy). In infiltrating breast carcinomas, complementary breast irradiation has been shown to significantly improve the local control and slightly the overall survival in five randomized trials. Following mastectomy, locoregional irradiation clearly reduces the chest wall and nodal relapse rates, especially in case of lesions more than 5 cm or with nodal involvement and/or large lymphatic or vascular emboli. Two recent randomized trials confirmed the benefit of well-adapted locoregional irradiation in all subgroups, especially in patients with one to three axillary involved nodes. In the Danish trial (including premenopausal high-risk women), radiotherapy reduced locoregional relapses from 32 to 9% (p < 0.001) and increased the 10-year survival rate from 45 to 54% (p < 0.001). In the Canadian trial, locoregional relapse rate decreased from 25 to 13% and the 10-year survival rate increased from 56 to 65%. The meta-analysis published in 1995 by the EBCTCG showed only a modest benefit due to locoregional irradiation in breast cancer. However, when small or old trials were excluded due to imperfect methodology or inadequate irradiation techniques, the benefit of modern radiotherapy became much more evident in a population of 7,840 patients. Locoregional irradiation appears to be able to reduce the risk of metastatic evolution occurring after local or nodal relapse and must be integrated in a multidisciplinary strategy. Treatment toxicity (especially toxicity due to irradiation of internal mammary nodes) is of special concern, as anthracycline-based chemotherapy is prescribed more often. The use of a direct field, with at least 60% of the dose delivered by electrons alternating with photons is recommended to protect the heart and lungs.

[Role of radiotherapy in the management of adenocarcinoma of the breast accessible to conservative surgery]

Standard treatment for limited stage adenocarcinoma of the breast includes lumpectomy (or a quadrantectomy), axillary node dissection, regional radiation therapy and, if the prognostic factors are unfavourable, chemotherapy and/or hormone therapy. This is supported by the results of American and European randomised trials. There have been many attempts at improving the modalities of conservative surgery and postoperative radiation therapy in order to maximize local control and minimize late sequellae. It is also likely that induction chemotherapy and external beam radiotherapy applied in selected cases increase the proportion of patients who can be offered conservative surgery.

Controversies in the local management of invasive and non-invasive breast cancer

Since the recent acceptance of partial mastectomy (lumpectomy or segmentectomy) as equivalent to mastectomy for survival, design of the local management of breast cancers has centered around concerns of local recurrence. There has been wide acceptance of the tumorectomy or lumpectomy approach by most authors in North America, while in Italy, following the Milan trials, there has been a preference for a segmental or quadrantectomy approach. The latter preferentially includes more ductal tissue toward and distant from the nipple and has shown a local recurrence rate less than 50% as great as that seen with lumpectomy. Radiotherapy dosages and techniques are of concern as well. If extensive ductal carcinoma in situ is a determinant of local recurrence, and if DCIS spreads preferentially along ducts in a radial fashion, then the extent of DCIS is most likely to be preferentially arrayed toward the nipple as well as in tissue on the other side of a tumor mass away from the nipple--such has been our knowledge of the ramifications of the ductal tree, in a radial fashion around the nipple. Acceptable cosmesis after a segmental approach to excision may be more difficult to obtain, but has been acceptable in some groups of patients. We may soon see a situation in which the operation is tailored to the specifics of an individual patient. The size of a resection, based on an even margin around a tumor mass (lumpectomy) or the number of degrees subtended by the arc representing the peripheral aspect of a segmental excision will depend on the size of the dominant lesion being resected, the size of the breast and any available data concerning the likely extent of the lesion, with DCIS having a special concern.

The importance of local control in the conservative treatment of breast cancer

The purpose of this study was to examine the meaning of local control, especially on survival, in breast cancer patients treated by lumpectomy with or without radiotherapy. We analyzed the survival results of four major published randomized trials that compare conservation surgery with or without radiation using three different statistical approaches: p-values, confidence intervals, and Bayesian techniques. All four trials report statistically significant increased local control and improved survival for the irradiated patients. Survival based on p-values and confidence intervals shows statistical significance for long-term follow-up of the NSABP-B06 trial, but not for the other trials, probably because of small sample sizes and short follow-up. At 10 years, the overall survival rates for the NSABP-B06 were 65% and 71% for lumpectomy alone or with radiation respectively. Interpreted in a Bayesian framework, the expected advantage in 10-year survival was 6% (the mean of NSABP-B06 10-year survival) with an 83% probability that the 10-year survival difference may lie between 2% and 10%. An 85% probability that 3% of patients will survive at 10 years because of irradiation translates into a 30% reduction in annual odds of death several years after treatment in stage I good prognosis patients and 15% in stage I poor prognosis patients. Analysis of the randomized trials comparing lumpectomy with or without radiation indicate a clear improvement in survival for the irradiated patients associated with increased local control. Combination of improved survival with the reduced psychological and economic costs associated with local recurrence argues well for the inclusion of radiation for many breast cancer patients.