Original p53 status predicts for pathological response in locally advanced breast cancer patients treated preoperatively with continuous infusion 5-fluorouracil and radiation therapy

Primary Chemoradiotherapy Treatment (PCRT) for HER2+ and Triple Negative Breast Cancer Patients: A Feasible Combination

Primary systemic treatment (PST) downsizes the tumor and improves pathological response. The aim of this study is to analyze the feasibility and tolerance of primary concurrent radio−chemotherapy (PCRT) in breast cancer patients. Patients with localized TN/HER2+ tumors were enrolled in this prospective study. Radiation was delivered concomitantly during the first 3 weeks of chemotherapy, and it was based on a 15 fractions scheme, 40.5 Gy/2.7 Gy per fraction to whole breast and nodal levels I-IV. Chemotherapy (CT) was based on Pertuzumab−Trastuzumab−Paclitaxel followed by anthracyclines in HER2+ and CBDCA-Paclitaxel followed by anthracyclines in TN breast cancers patients. A total of 58 patients were enrolled; 25 patients (43%) were TN and 33 patients HER2+ (57%). With a median follow-up of 24.2 months, 56 patients completed PCRT and surgery. A total of 35 patients (87.5%) achieved >90% loss of invasive carcinoma cells in the surgical specimen. The 70.8% and the 53.1% of patients with TN and HER-2+ subtype, respectively, achieved complete pathological response (pCR). This is the first study of concurrent neoadjuvant treatment in breast cancer in which three strategies were applied simultaneously: fractionation of RT (radiotherapy) in 15 sessions, adjustment of CT to tumor phenotype and local planning by PET. The pCR rates are encouraging.

Predictive Factors of Long-Term Survival after Neoadjuvant Radiotherapy and Chemotherapy in High-Risk Breast Cancer

Simple Summary

This retrospective analysis reports on the treatment outcomes of women diagnosed with high-risk breast cancer treated with chemotherapy in combination with radiotherapy before the surgical removal of the tumor. It is well established that the lack of visible tumor cells in the pathological tumors analysis by the time of surgery (known as pathological complete response, pCR) is a factor that improves survival without the tumor reappearing in the body. However, it is unknown whether that is only true when giving systemic therapy or when pCR is achieved with the help of radiotherapy. We collected patient information and survival times to analyze the outcome in our patient group. We found that women with a pCR treated with chemotherapy in combination with radiotherapy can expect favorable long-term survival. This was true across different types of breast cancer and chemotherapy substances.

Abstract

Background: Neoadjuvant radiotherapy (naRT) in addition to neoadjuvant chemotherapy (naCT) has been used for locally advanced, inoperable breast cancer or to allow breast conserving surgery (BCS). Retrospective analyses suggest that naRT + naCT might result in an improvement in pathological complete response (pCR rate and disease-free survival). pCR is a surrogate parameter for improved event-free and overall survival (OS) and allows for the adaption of the post-neoadjuvant therapy regimens. However, it is not clear whether pCR achieved with the addition of naRT has the same prognostic value. Patients and methods: We performed a retrospective re-analysis of 356 patients (cT1-cT4/cN0-N+) treated with naRT and naCT with a long-term follow-up. Patients underwent naRT on the breast and regional lymph nodes combined with a boost to the primary tumor. Chemotherapy with different agents was given either sequentially or concomitantly to naRT. We used the Cox proportional hazard regression model to estimate the effect of pCR in our cohort in different subgroups as well as chemotherapy protocols. Clinical response markers correlating with OS were also analyzed. Results: For patients with median follow-ups of 20 years, 10 years, 15 years, 20 years, and 25 years, OS rates were 69.7%, 60.6%, 53.1%, and 45.1%, respectively. pCR was achieved in 31.1% of patients and associated with a significant improvement in OS (HR = 0.58; CI-95%: 0.41–0.80; p = 0.001). The prognostic impact of pCR was evident across breast cancer subtypes and chemotherapy regimens. Multivariate analysis showed that age, clinical tumor and nodal stage, chemotherapy, and pCR were prognostic for OS. Conclusion: NaCT and naRT prior to surgical resection achieve good long-term survival in high-risk breast cancer. pCR after naRT maintains its prognostic value in breast cancer subtypes and across different subgroups. pCR driven by naRT and naCT independently influences long-term survival.

Results of a phase I-II study of adjuvant concurrent carboplatin and accelerated radiotherapy for triple negative breast cancer

Purpose: To determine feasibility and explore the clinical efficacy of concurrent radiotherapy and carboplatin as adjuvant treatment of triple negative breast cancer (TNBC). Patients and Methods: Women with Stage I-II TNBC were treated after surgery in a phase I-II prospective trial [NCT01289353]. Weekly carboplatin (AUC = 2.0) was delivered for 6 weeks. Concurrent radiotherapy was delivered in the prone position during weeks 2-4, for a total dose of 40.5 Gy in 15 fractions to the breast, and 46.5 Gy in 17 fractions to the tumor bed. Adverse events (AE) were assessed weekly during treatment, once at 45-60 d, and every 6 mo thereafter, using the Common Terminology Criteria for AE (CTCAE) v3.0. Results: A total of 39 patients accrued and 36 received treatment. Eight patients (22%, exact 95% CI: 10%, 39%) developed grade 2 or greater acute radiation dermatitis. Overall, grade 2 AE were seen in nine and grade 3 in two patients. Twenty-three patients (64%) received additional adjuvant chemotherapy. With a median follow-up of 48 mo, 34/36 (94%) are alive and disease free. One patient died of pulmonary failure with possible but unproven breast cancer recurrence, and one patient died of pelvic malignancy. One patient recurred locally and is alive and disease free after surgical management. Brisk lymphocytic infiltrate was present pre-treatment in 39% of 18 patients with evaluable tumor. Conclusions: Adjuvant concurrent carboplatin and prone accelerated radiotherapy is a well-tolerated and promising treatment of early stage TNBC. The observed 3% compares favorably with the expected 30% recurrence rate within 1-4 y from treatment, warranting further studies.

Comparison of two radiation techniques for the breast boost in patients undergoing neoadjuvant treatment for breast cancer

OBJECTIVE

After breast conservative surgery (BCS) and whole-breast radiotherapy (WBRT), the use of boost irradiation is recommended especially in patients at high risk. However, the standard technique and the definition of the boost volume have not been well defined.

METHODS

We retrospectively compared an anticipated pre-operative photon boost on the tumour, administered with low-dose fractionated radiotherapy, and neoadjuvant chemotherapy with two different sequential boost techniques, administered after BCS and standard adjuvant WBRT: (1) a standard photon beam (2) and an electron beam technique on the tumour bed of the same patients. The plans were analyzed for the dosimetric coverage of the CT-delineated irradiated volume. The minimal dose received by 95% of the target volume (D95), the minimal dose received by 90% of the target volume (D90) and geographic misses were evaluated.

RESULTS

15 patients were evaluated. The sequential photon and electron boost techniques resulted in inferior target volume coverage compared with the anticipated boost technique, with a median D95 of 96.3% (range 94.7-99.6%) and 0.8% (range 0-30%) and a median D90 of 99.1% (range 90.2-100%) and 54.7% (range 0-84.8%), respectively. We observed a geographic miss in 26.6% of sequential electron plans. The results of the anticipated boost technique were better: 99.4% (range 96.5-100%) and 97.1% (range 86.2-99%) for median D90 and median D95, respectively, and no geographic miss was observed. We observed a dose reduction to the heart, with left-sided breast irradiation, using the anticipated pre-operative boost technique, when analyzed for all dose-volume parameters. When compared with the sequential electron plans, the pre-operative photon technique showed a higher median ipsilateral lung Dmax.

CONCLUSION

Our data show that an anticipated pre-operative photon boost results in a better coverage with respect to the standard sequential boost while also saving the organs at risk and consequently fewer side effects.

ADVANCES IN KNOWLEDGE

This is the first dosimetric study that evaluated the association between an anticipated boost and neoadjuvant chemotherapy treatment.

Tumor RNA disruption predicts survival benefit from breast cancer chemotherapy

In a prior substudy of the CAN-NCIC-MA.22 clinical trial (ClinicalTrials.gov identifier NCT00066443), we observed that neoadjuvant chemotherapy reduced tumor RNA integrity in breast cancer patients, a phenomenon we term "RNA disruption." The purpose of the current study was to assess in the full patient cohort the relationship between mid-treatment tumor RNA disruption and both pCR post-treatment and, subsequently, disease-free survival (DFS) up to 108 months post-treatment. To meet these objectives, we developed the RNA disruption assay (RDA) to quantify RNA disruption and stratify it into 3 response zones of clinical importance. Zone 1 is a level of RNA disruption inadequate for pathologic complete response (pCR); Zone 2 is an intermediate level, while Zone 3 has high RNA disruption. The same RNA disruption cut points developed for pCR response were then utilized for DFS. Tumor RDA identified >fourfold more chemotherapy non-responders than did clinical response by calipers. pCR responders were clustered in RDA Zone 3, irrespective of tumor subtype. DFS was about 2-fold greater for patients with tumors in Zone 3 compared to Zone 1 patients. Kaplan-Meier survival curves corroborated these findings that high tumor RNA disruption was associated with increased DFS. DFS values for patients in zone 3 that did not achieve a pCR were similar to that of pCR recipients across tumor subtypes, including patients with hormone receptor positive tumors that seldom achieve a pCR. RDA appears superior to pCR as a chemotherapy response biomarker, supporting the prospect of its use in response-guided chemotherapy.

Efficacy of concurrent chemoradiotherapy for patients with locally recurrent or advanced inoperable breast cancer

BACKGROUND

This study aimed to assess the efficacy and safety of chemoradiotherapy (CRT) for locally recurrent or advanced inoperable breast cancer.

PATIENTS AND METHODS

Twenty patients treated between 2009 and 2013 were reviewed from a prospectively collected database. All patients had symptomatic recurrent or advanced breast cancer and had been deemed not to be ideal operative candidates. Treatment consisted of external beam radiotherapy to the primary tumor in the breast or regional lymph nodes, or both, concurrent with either capecitabine, paclitaxel, or cisplatin/etoposide chemotherapy. The grade of acute and late toxicity was evaluated, as was response to treatment, overall survival (OS), and local relapse-free survival (LRFS).

RESULTS

Of the 20 patients, 9 (45%) presented with primary disease and 11 (55%) had recurrent disease. A total of 11 (55%) patients had evidence of metastatic disease. The overall clinical response rate was 100%, with a clinical complete response (CR) observed in 65% of patients and a clinical partial response (PR) observed in 35% of patients. At a median follow up of 25.3 months, 2-year LRFS was 73% and 2-year OS was 80%. Local control was significantly better in patients with an initial diagnosis (hazard ratio [HR], 0.139; 95% confidence interval [CI], 0.014-0.935) and in those who had not had previous in-field radiation (HR, 0.011; 95% CI, 0.005-0.512). The only grade ≥ 3 toxicity was acute dermatologic events (30%) and late dermatologic (15%) events.

CONCLUSION

Concurrent CRT with capecitabine, paclitaxel, or cisplatin/etoposide for recurrent or advanced inoperable breast cancer is well tolerated with impressive clinical response rates and durable local control.

Preoperative radio-chemotherapy in early breast cancer patients: long-term results of a phase II trial

PURPOSE

This phase II trial aimed to investigate the efficacy of concurrent radio- (RT) and chemotherapy (CT) in the preoperative setting for operable, non-metastatic breast cancer (BC) not amenable to initial breast-conserving surgery (BCS).

PATIENTS AND METHODS

From 2001 to 2003, 59 women were included. CT consisted of four cycles of 5-FU, 500 mg/m(2)/d, continuous infusion (d1-d5) and vinorelbine, 25 mg/m(2) (d1 and d6). Starting concurrently with the second cycle, RT delivered 50 Gy to the breast and 46 Gy to the internal mammary and supra/infra-clavicular areas. Breast surgery and lymph node dissection were then performed. Adjuvant treatment consisted of a 16 Gy boost to the tumor bed after BCS, FEC (four cycles of fluorouracil 500 mg/m(2), cyclophosphamide 500 mg/m(2), and epirubicin 100 mg/m(2), d1; d21) for pN1-3 and hormone-therapy for positive hormone receptors BC.

RESULTS

The in-breast pathological complete response rate was 27%. BCS was performed in 41 (69%) pts. Overall and distant-disease free survivals at 5 years were respectively 88% [95% CI 80-98] and 83% [95% CI 74-93] whereas locoregional and local controls were 90% [95% CI 82-97] and 97% [95% CI 92-100]. Late toxicity (CTCAE-V3) was assessed in 51 pts (86%) with a median follow-up of 7 years [5-8]. Four (8%) experienced at least one grade III toxicities (one telangectasia and three fibroses). Cosmetic results, assessed in 35 of the 41 pts (85%) who retained their breasts, were poor in four pts (11%).

CONCLUSION

Preoperative concurrent administration of RT and CT is an effective regimen. Long-term toxicity is moderate. This association deserves further evaluations in prospective trials.

Preoperative concurrent paclitaxel-radiation in locally advanced breast cancer: pathologic response correlates with five-year overall survival

We have previously demonstrated high pathologic response rates after neoadjuvant concurrent chemoradiation in patients with locally advanced breast cancer (LABC). We now report disease-free survival (DFS) and overall survival (OS) in the context of pathologic response. 105 LABC patients (White 46%, Non-White 54%) were treated with paclitaxel (30 mg/m² intravenously twice a week) for 10-12 weeks. Daily radiotherapy was delivered to breast, axillary, and supraclavicular lymph nodes during weeks 2-7 of paclitaxel treatment, at 1.8 Gy per fraction to a total dose of 45 Gy with a tumor boost of 14 Gy at 2 Gy/fraction. Pathological complete response (pCR) was defined as the absence of invasive cancer in breast and lymph nodes and pathological partial response (pPR) as the persistence of <10 microscopic foci of invasive carcinoma in breast or lymph nodes. Pathologic response (pCR and pPR) after neoadjuvant chemoradiation was achieved in 36/105 patients (34%) and was associated with significantly better DFS and OS. Pathological responders had a lower risk of recurrence or death (HR = 0.35, P = 0.01) and a longer OS (HR = 4.27, P = 0.01) compared with non-responders. Median DFS and OS were 57 and 84 months for non-responders, respectively, and have not yet been reached for responders. Importantly, pathologic response was achieved in 54% of patients with HR negative tumors (26/48). In conclusion, pathologic response to concurrent paclitaxel-radiation translated into superior DFS and OS. Half of the patients with HR negative tumors achieved a pathologic response.

Deletion of p53 in human mammary epithelial cells causes chromosomal instability and altered therapeutic response

The TP53 tumor suppressor gene is the most commonly mutated gene in human cancers. To evaluate the biological and clinical relevance of p53 loss, human somatic cell gene targeting was used to delete the TP53 gene in the non-tumorigenic epithelial cell line, MCF-10A. In all four p53-/- clones generated, cells acquired the capability for epidermal growth factor-independent growth and were defective in appropriate downstream signaling and cell cycle checkpoints in response to DNA damage. Interestingly, p53 loss induced chromosomal instability leading to features of transformation and the selection of clones with varying phenotypes. For example, p53-deficient clones were heterogeneous in their capacity for anchorage-independent growth and invasion. In addition, and of clinical importance, the cohort of p53-null clones showed sensitivity to chemotherapeutic interventions that varied depending not only on the type of chemotherapeutic agent, but also on the treatment schedule. In conclusion, deletion of the TP53 gene from MCF-10A cells eliminated p53 functions, as well as produced p53-/- clones with varying phenotypes possibly stemming from the distinct chromosomal changes observed. Such a model system will be useful to further understand the cancer-specific phenotypic changes that accompany p53 loss, as well as help to provide future treatment strategies for human malignancies that harbor aberrant p53.

Mutation and accumulation of p53 related to results of adjuvant therapy of postmenopausal breast cancer patients

p53 protein accumulation and gene mutation have been implicated in resistance to cytotoxic treatment. This study was performed to further assess the predictive value of p53 in breast cancer. Postmenopausal patients were randomized to adjuvant chemotherapy with cyclophosphamide, metothrexate, or 5-fluorouracil (CMF) vs. postoperative radiotherapy. The patients were also randomized to adjuvant tamoxifen vs. no endocrine treatment. Immunohistochemistry (IHC) and single-strand conformation polymorphism (SSCP), followed by direct sequencing, was performed. The p53 altered group, regarded as positive for p53 gene mutation and/or p53 protein accumulation, tended to benefit more from CMF than from radiotherapy as compared with others regarding distant recurrences. In the group lacking p53 alteration there was a significantly decreased local recurrence rate in the radiotherapy group as compared with the CMF group (RR = 0.24, 95% CI = 0.083 0.62), whereas no benefit from radiotherapy was found for patients showing p53 alterations. Tamoxifen significantly decreased the rate of distant recurrence for estrogen receptor-positive patients with no apparent difference in relation to p53 alteration. It is suggested that p53 alteration indicates benefit from CMF compared with radiotherapy regarding distant recurrence-free survival and the best local control with radiotherapy is achieved in the absence of p53 alteration. Finally, altered p53 status is probably not a marker of resistance to tamoxifen.

Combining systemic therapies with radiation in breast cancer

Over the last years, significant survival benefits for breast cancer were derived from the use of postoperative systemic therapies and radiotherapy. Although these two modalities have been extensively used, the optimal strategies of their combining remain debatable. There have been few randomized studies addressing this issue and their results are generally inconclusive. This article reviews combining systemic therapies (chemotherapy, hormonotherapy and trastuzumab) with radiation in breast cancer patients. In clinical practice, chemotherapy and radiotherapy are most commonly used sequentially but this strategy is not based on level 1 evidence. Increased cardiotoxicity and skin reactions preclude the concomitant radiotherapy and anthracycline-based chemotherapy. Further investigations are warranted to determine the safety of taxane-based schedules used concomitantly with radiotherapy, particularly with regard to pneumotoxicity. Concurrent chemo-radiotherapy with the use of selected schemes may be considered in patients with locally advanced cancer but this strategy still needs to be verified in large randomized studies. The optimal combination of tamoxifen and aromatase inhibitors with radiotherapy has also not been determined in randomized trials and the results of retrospective studies are inconsistent. Finally, the data on combining targeted therapies with radiation are still scarce and do not allow for meaningful conclusions.

Local control by radiotherapy: is that all there is?

Radiotherapy is a local treatment modality employed in breast cancer to reduce local recurrence following surgery. The observed association of optimal local control with improved survival was not expected in a disease characterized by early systemic spread. The underlying mechanisms whereby the application of ionizing radiation to the primary tumor site can have systemic effects remain unclear and are the subject of much debate. In the present article we discuss the hypothesis that radiotherapy has unique biological effects and that, in addition to killing residual neoplastic cells after surgery is performed, it might favorably alter the microenvironment at the primary tumor site during the process of wound healing and the development of antitumor immune responses.

Selective Mastectomy in the Management of Locally Advanced Breast Cancer

PURPOSE

To evaluate local control for patients with locally advanced noninflammatory breast cancer (LABC) managed by selective mastectomy.

METHODS AND MATERIALS

Between 1979 and 1996, 176 patients with LABC were prospectively managed by chemotherapy (CT)-irradiation (RT)-CT without routine mastectomy. All surviving patients were followed for a minimum of 5 years.

RESULTS

A total of 132 patients (75%) had a T4 tumor and 22 (12.5%) supraclavicular nodal disease. The clinical complete response rate was 91% (160/176), which included 13 patients who underwent mastectomy and 2 an iridium wire implant. The first site of failure was local for 43 patients (breast +/- axilla for 38); 27 of these patients underwent salvage mastectomy and 11 did not for an overall mastectomy rate of 23% (40/176). If all 176 patients had undergone routine mastectomy (136 extra mastectomies), 11 additional patients may have avoided an unsalvageable first local relapse. The others would have either have not had a local relapse or would have suffered local relapse after distant disease. No tumor or treatment related factor was found to predict local disease at death. Median disease-free and overall survival for all patients was 26 and 52 months, respectively.

CONCLUSIONS

Selective mastectomy in LABC may not jeopardize local control or survival.

Pathological response to preoperative concurrent chemo-radiotherapy for breast cancer: results of a phase II study

This study evaluated, in terms of pathological complete response (pCR) and acute toxicity, preoperative concurrent (5-fluorouracil (5-FU)-vinorelbine) chemoradiotherapy for large breast cancers. A total of 60 women were included in the study. Chemotherapy consisted of 4 cycles of 5-FU, 500 mg/m2/d, continuous infusion (d1-d5) and vinorelbine, 25 mg/m2 (d1; d6). Starting with the second cycle, radiotherapy delivered 50 Gy to the breast and 46 Gy to the internal mammary and supra/infra-clavicular lymph nodes. Breast surgery and axillary lymph node dissection were then performed. Four patients did not complete their chemotherapy. Breast conservation was possible in 69% of patients. The rate of pCR was 27%. Three factors were associated with pCR: histological grade 3, absence of hormonal receptors and high mitotic index. Grade 4 haematological toxicity occurred in 22% of patients. In conclusion, chemoradiotherapy demonstrated good efficacy, both in terms of pCR and in allowing breast conservation with acceptable tolerance.

Neoadjuvant concurrent paclitaxel and radiation in stage II/III breast cancer

PURPOSE

The aim of this study was to determine the safety and pathologic response rates following neoadjuvant paclitaxel and radiation in patients with stage II/III breast cancer and to evaluate the use of sequential biopsies to allow an in vivo assessment of biological markers as potential predictive markers of response to this regimen.

PATIENTS AND METHODS

Patients with high-risk, operable breast cancer were treated with three cycles of paclitaxel 175 mg/m2 every 3 weeks, followed by twice-weekly paclitaxel 30 mg/m2 and concurrent radiation. Core biopsies were obtained at baseline and 24 to 72 hours after the first cycle of paclitaxel. After completing neoadjuvant treatment, patients underwent definitive surgery. The primary end point was pathologic complete response, which is defined as the absence of any invasive cancer at surgery. Potential markers of therapeutic response were evaluated including markers of proliferation, apoptosis, p21, HER2, estrogen receptor, and progesterone receptor status.

RESULTS

Of the 38 patients enrolled, 13 (34%) had a pathologic complete response. There was no significant difference in baseline Ki-67 between responders (35%) and nonresponders (28%; P = 0.45). There was also no significant change in Ki-67 following paclitaxel administration. Despite this lack of immunohistologic change in proliferative activity, baseline mitotic index was higher for patients with pathologic complete response over nonresponders (27 versus 10, P = 0.003). Moreover, the increase in mitotic index following paclitaxel administration was associated with pathologic complete response.

CONCLUSIONS

Neoadjuvant paclitaxel/radiation is effective and well tolerated. Tumor proliferation at baseline and response to chemotherapy as measured by mitotic activity may serve as an important indicator of pathologic response to neoadjuvant paclitaxel/radiation.

Concomitant radiation therapy and paclitaxel for unresectable locally advanced breast cancer: Results from two consecutive Phase I/II trials

PURPOSE

The management of unresectable locally advanced breast cancer (ULABC) remains a major challenge because of the necessity both to treat local disease and to prevent distant disease. Two consecutive Phase I/II trials of concomitant chemotherapy and radiation (CRT) were performed to attempt to address both local and distant disease control in ULABC. This analysis focuses on rates of locoregional control and radiation-associated acute and late complications.

METHODS AND MATERIALS

Thirty-three patients with unresectable locally advanced or inflammatory breast cancers (T4N0-3M0-1) or locally recurrent disease were treated with CRT on two consecutive Phase I/II trials. Radiotherapy consisted of 60-70 Gy to the breast or chest wall and 60 Gy to draining lymphatics in a week-on/week-off (WO/WO) schedule. Chemotherapy consisted of either continuous infusion or bolus paclitaxel +/- vinorelbine. A subset analysis of 16 patients with nonmetastatic ULABC Stage IIIB-C (T4N0-3M0) was performed. Among this cohort, 13 patients (81%) underwent planned mastectomy after CRT.

RESULTS

Of the 16 patients with Stage IIIB-C disease, acute toxicity included moist desquamation (n = 8) and Grade 3-4 neutropenia (n = 3). Late toxicity included breast reconstruction loss, decreased range of arm motion, lymphedema, and skin toxicity, although none was life-threatening. Of 15 assessable patients, 14 had a clinical response, 7 had a pathologic complete response (pCR) including 6 of 13 patients undergoing mastectomy. With a median follow-up for living patients of 43.8 months, the 4-year actuarial locoregional control, disease-free survival, and overall survival were 83%, 33%, and 56% respectively.

CONCLUSIONS

Concurrent WO/WO radiation therapy and paclitaxel +/- vinorelbine is effective locoregional therapy for ULABC with an acceptable toxicity profile. Further investigation of concurrent chemoradiotherapy in ULABC is warranted.

[Association of taxanes and radiotherapy: preclinical and clinical studies]

Taxanes (paclitaxel and docetaxel) stabilized microtubules against depolymerization, and inhibit their function. Their radiosensitizing properties have been discovered more than 10 years ago; they synchronized tumor cells in G2/M phase, the most radiosensitive portion of the cell cycle. Other radiosensitizing mechanisms have been also discussed, as reoxygenation, promotion of radio-apoptosis and antiangiogenic cooperation. Many phase I and II studies have been performed, essentially in bronchus and head and neck carcinomas. In lung cancer, paclitaxel was delivered weekly at a dose of 60 mg/m2. Many studies combined cisplatin or carboplatin with paclitaxel, demonstrating that this combination is feasible and efficient. Only one phase III trial was reported; after two cycles of chemotherapy for inoperable lung cancers, radiotherapy was delivered, with or without paclitaxel radiosensitization: a benefit in disease-free survival was observed for the combination arm. In head and neck carcinomas, conomitant association of cisplatin, paclitaxel and radiation was feasible and showed promising results. Clinical trials with docetaxel are in progress.

Docetaxel and Cisplatin as Primary Chemotherapy for Treatment of Locally Advanced Breast Cancers

A phase II trial was designed to evaluate the effectiveness of docetaxel/cisplatin as primary or neoadjuvant chemotherapy of locally advanced breast carcinoma (LABC). Patients with newly diagnosed breast cancers > or = 5 cm in size by palpation were treated with docetaxel/cisplatin, both at 70 mg/m2 intravenously every 21 days for 4 courses. Upon completion of chemotherapy, all patients underwent modified radical mastectomy with axillary nodal dissection. Pathologic complete response (pCR) was defined as absence of any invasive carcinoma in the breast. Standard AC (doxorubicin/cyclophosphamide) at 60 mg/m2 and 600 mg/m2, respectively, for 4 cycles was given as adjuvant therapy to maximally eradicate occult distant disease. Between March 1998 and October 2001, 57 women were entered onto this trial, 28 (49%) with inoperable T4 and inflammatory cancers. Pretreatment median tumor size was 9 cm. Thirty-six patients (63%) had estrogen receptor-positive tumors and 10 patients (18%) had tumors with HER2 overexpression. All tumors became operable after neoadjuvant chemotherapy. Pathologic complete response in the breast was achieved in 15 patients (26%) and pCR in the breast and the axilla was achieved in 11 patients (20%). All neoadjuvant chemotherapy courses were administered at full doses without treatment delays caused by toxicity. The most common side effects were hyperglycemia, anemia, and mild neuropathy. The results of this study suggest that the docetaxel/cisplatin combination can be an effective and well-tolerated induction treatment of LABC, even in very large mostly HER2-nonoverexpressing tumors.

P53 and breast cancer

p53 mutation is the most common genetic abnormality found so far in human cancer, and in breast cancer p53 mutation/alteration is seen in up to 50% of primary carcinomas. Together with the increasing knowledge of the characteristics and understanding of the role of p53 over the last two decades, attention in recent years has been focused on how this knowledge can be used in clinical settings for patient care and management in terms of analyzing p53 as a potential marker for studying the relationship between p53 expression and tumour development, progression and outcome; and designing alternative treatment strategies specifically aimed at restoring normal p53 function.

Preoperative twice-weekly paclitaxel with concurrent radiation therapy followed by surgery and postoperative doxorubicin-based chemotherapy in locally advanced breast cancer: a phase I/II trial

PURPOSE

Preoperative chemotherapy is the conventional primary treatment in locally advanced breast cancer (LABC). We investigated the safety and efficacy of primary twice-weekly paclitaxel and concurrent radiation (RT) before modified radical mastectomy followed by adjuvant doxorubicin-based chemotherapy.

PATIENTS AND METHODS

Stage IIB (T3N0) to III LABC patients were eligible. Primary chemoradiation consisted of paclitaxel, 30 mg/m(2) delivered intravenously for 1 hour twice weekly for a total of 8 to 10 weeks, and concurrent RT (45 Gy at 1.8 Gy/fraction). Modified radical mastectomy was performed at least 2 weeks after completion of chemoradiation or on recovery of skin toxicity. Postoperatively, patients who responded to paclitaxel and RT received four cycles of doxorubicin/paclitaxel, whereas patients who did not respond received doxorubicin/cytoxan.

RESULTS

Forty-four patients were accrued. Toxicity from paclitaxel/RT included grade 3 skin desquamation (7%), hypersensitivity (2%), and stomatitis (2%). Postsurgery complications occurred in six patients (14%). The only grade 4 toxicity of postmastectomy chemotherapy was hematologic (10%). Grade 3 toxicities were leukopenia (24%), infection (22%), peripheral neuropathy (17%), arthralgia and pain (17%), stomatitis (12%), fatigue (10%), esophagitis (5%), and nausea (2%). Overall clinical response rate to preoperative paclitaxel and RT was 91%. Thirty-four percent of patients achieved a pathologic response in the mastectomy specimen: 16% pathologic complete responses (clearance of invasive cancer in the breast and axillary contents) and 18% pathologic partial responses (< 10 residual microscopic foci of invasive breast cancer).

CONCLUSION

Twice-weekly paclitaxel with concurrent RT is a feasible and effective primary treatment for LABC. Future studies should compare primary chemoradiation to chemotherapy in LABC.

Study of suboptimum treatment response: lessons from breast cancer

Drug resistance is the main cause of therapeutic failure and death in patients with cancer. However, there have been surprisingly few studies designed specifically to investigate the mechanisms underlying poor treatment response in vivo, compared with the number of phase II and III trials investigating treatment effects. We can now analyse the expression patterns of multiple genes by use of microarrays, rapid gene sequencing, and proteomics, and so need to reassess the way we design clinical trials to take full advantage of these new opportunities. I discuss the concept of clinical studies of chemoresistance in terms of the collection of tumour samples for biological studies, the use of appropriate clinical settings, and the importance of trial design. Ideally, such studies should investigate specific biological features in relation to measurable antitumour effects of single drugs.

Low HER2/neu gene expression is associated with pathological response to concurrent paclitaxel and radiation therapy in locally advanced breast cancer

PURPOSE

The objective of this study was twofold: first, to identify patients with locally advanced breast cancer (LABC) who will achieve a pathological response to a preoperative regimen of concurrent paclitaxel and radiation; and second, to explore associations between molecular markers from the original tumors and pathological response.

METHODS AND MATERIALS

Patients with previously untreated LABC were eligible to receive a regimen of preoperative concurrent paclitaxel, 30 mg/m(2) twice a week for a total of 8 weeks, and radiation delivered Weeks 2--6, 45 Gy at 1.8 Gy per fraction to the breast, ipsilateral axilla, and supraclavicular nodes. At mastectomy, pathologic findings were classified as pathological complete response (pCR) = no residual invasive cells in the breast and axillary contents; pathological partial response (pPR) = presence of < or = 10 microscopic foci of invasive cells; no pathological response (pNR) = pathological persistence of tumor. For each patient, pretreatment breast cancer biopsies were prospectively analyzed by immunohistochemistry (IHC) for estrogen and progesterone (ER/PR) hormonal receptors, HER2/neu and p53 overexpression. Estrogen receptor (ER), HER2/neu, metablastin, beta-tubulin III and IV, microtubule-associated protein-4 (MAP-4), bcl-2, bax, and cyclooxygenase-2 (COX-2) gene expression were measured using real-time quantitative polymerase chain reaction (PCR).

RESULTS

A total of 36 patients had pretreatment biopsies and were evaluable for the analysis of the association of molecular markers with pathological response. Pathological response in the mastectomy specimen was achieved in 12 of these 36 patients (33%). Only HER2/neu and ER gene expression were found to be significantly associated with the extent of pathological response to the regimen, i.e., tumors with low HER2/neu gene expression and negative estrogen receptors were more likely to respond to the tested regimen (p = 0.009 and p = 0.006, respectively). Conversely, p53 protein expression measured by IHC did not appear to be associated with pathological response (p = 0.67).

CONCLUSION

Further studies in LABC should assess whether patient selection for treatment based on the original tumor molecular characteristics could affect their chance to achieve a pathological response.

Taxanes in combined modality therapy for solid tumors

The taxanes, paclitaxel and docetaxel, are novel antimitotic agents that are under extensive investigation in clinical trials. Both taxanes have demonstrated significant activity against many solid tumors as single agents and in combination with other chemotherapeutic agents. In addition, taxanes arrest cells at the G2/M phase of the cell cycle, which is the most radiosensitive phase. These properties are exploited in clinical trials combining this taxane with radiation therapy. Most studies included patients with non-small cell lung cancer (NSCLC) and cancers of the head and neck and there are a few studies with concurrent taxane/RT in esophageal, gastric, pancreatic, brain and breast cancer. Information concerning the tolerability and possible utility of docetaxel is also becoming available. This manuscript will review some of the more prominent trials of the taxanes in combination with radiation therapy for solid tumors.

Tp53 gene therapy: a key to modulating resistance to anticancer therapies?

Abnormalities in the p53 tumor suppressor have been identified in over 60% of human cancers. The status of p53 within tumor cells has been proposed to be one of the major determinants of the response to anticancer therapies. In this review we examine the relationship between functional p53 and sensitivity, or resistance, to chemotherapy and radiotherapy. We also discuss the potential of current gene-therapy approaches to restore functional p53 to tumors as a means of modulating the effects of radiation and chemotherapy.

Clinicopathologic Analysis of Fas, Fas Ligand, and Other Biomarkers in Locally Advanced Breast Carcinoma

Fas and Fas ligand (FasL) mediate T-lymphocyte cytotoxicity and may also induce physiologic apoptosis in breast epithelium associated with menstruation and cessation of lactation. Altered expression may thus be associated with breast carcinoma progression, chemotherapy response, or outcome. We performed a clinicopathologic analysis of immunohistochemical staining for Fas and FasL, as well as bax, bcl-2, glutathione-s-transferase, HER-2 (c-erbB-2), Ki67, P-glycoprotein, p53, and hormone receptors in pretreatment breast biopsies from 34 patients with locally advanced or limited stage IV breast carcinoma who received preoperative (neoadjuvant, primary) chemotherapy followed by lumpectomy or mastectomy. Neoplastic cells expressed Fas in 44% and FasL in 85% of pretreatment biopsies. Fas immunostaining was more frequent in tumors with larger size (p = 0.02) and pretreatment metastases (p = 0.03). Combined Fas and p53 staining correlated with pathologic complete response (4 of 5 CR versus 6 of 29 other, p = 0.02), as did combined p53 and lack of FasL staining (2 of 5 CR versus 0 of 29 other, p = 0.02), but individually Fas, p53, and lack of FasL immunostaining demonstrated only trends to correlation with CR (p = 0.13-0.15). No other biomarkers correlated with chemotherapeutic response. Neither FasL nor Fas expression was associated with the degree of peritumoral lymphocytic infiltration, or with expression of the other biomarkers. Recurrence was more frequent in Fas-expressing tumors (recurrent cases 7 of 10 Fas positive versus nonrecurrent 8 of 24 Fas positive, p = 0.07). In this patient group, Fas expression is associated with aggressive tumor behavior. Biomarker immunostaining correlates weakly with pathologic response to preoperative chemotherapy, in keeping with complex or heterogeneous tumor-drug interactions.

Does p53 status influence tumor response to anticancer therapies?

Abnormalities in the tumor suppressor gene p53 have been identified in over 60% of human cancers. Since it plays such a pivotal role in cell growth regulation and apoptosis, the status of the p53 gene has been proposed as one of the major determinants of a tumor's response to anticancer therapies. In this review we examine the relationship between functional p53 and sensitivity/resistance to both chemotherapy and radiotherapy, and discuss the potential use of some of the current gene therapy approaches to restore functional p53 to tumors as a means of modulating the effects of radiation and chemotherapy.

The contribution of molecular markers to the prediction of response in the treatment of breast cancer: a review of the literature on HER-2, p53 and BCL-2

BACKGROUND

The selection of therapies for breast cancer is today based on prognostic features (chemotherapy, radiotherapy), hormone receptor status (hormonal therapy) and HER-2 status (trastuzumab therapy). HER-2, p53 and BCL-2 are tumour-related proteins that have the potential to further improve individualisation of patient management, by predicting response to chemotherapy, hormonal therapy and radiotherapy.

MATERIALS AND METHODS

This paper reviews the rationale for the use of these proteins as predictive factors, as well as the published literature addressing the use of each one to predict response to hormonal therapy, chemotherapy and radiotherapy.

RESULTS

HER-2, p53 and BCL-2 remain inadequately assessed as predictive factors in breast cancer. HER-2 evaluation is required for the selection of patients for trastuzumab (Herceptin) therapy, as trials of this therapy have been limited to HER-2 overexpressors. HER-2 overexpression may be predictive of resistance to hormonal therapy. Anthracyclines are effective therapy for breast cancer regardless of HER-2 status, but patients whose tumours overexpress HER-2 appear to receive the greatest relative benefit from this therapy. Studies of HER-2 as a predictor of response to CMF and to radiotherapy are inconclusive at this time. No data yet exist to support the use of p53 or BCL-2 as predictive factors in the therapy of breast cancer.

CONCLUSIONS

At this point in time, there is inadequate evidence to support the use of HER-2, p53 or BCL-2 to guide the selection of hormonal therapy, chemotherapy or radiotherapy for breast cancer.

An update on radiation therapy in breast cancer

Radiation therapy plays an important role in the management of both invasive and noninvasive breast cancer. During the last 20 years, the availability of radiation therapy has made it possible to test the feasibility and safety of breast preservation after the diagnosis of early-stage breast cancer. This article summarizes some of the ongoing controversies concerning the use of radiation therapy in the multidisciplinary management of breast cancer.