Preoperative paclitaxel and radiotherapy for locally advanced breast cancer: surgical aspects

Effect of Neoadjuvant Concurrent Chemoradiation on Operability and Survival in Locally Advanced Inoperable Breast Cancer

PURPOSE

Inoperable locally advanced breast cancers (LABCs) are treated with neoadjuvant chemotherapy. We studied the use of neoadjuvant concurrent chemoradiation (NACCRT) in patients with inoperable LABC.

METHODS AND MATERIALS

From May 2017 to December 2021, the study recruited patients with stage III inoperable LABC. Treatment included 4 cycles of doxorubicin and cyclophosphamide and 4 cycles of paclitaxel, along with concurrent radiation therapy to a total dose of 46 Gy. Thereafter, all patients were evaluated for surgery, and additional treatments were given based on receptor status. The effects of NACCRT on pathologic complete response (pCR), operability, and survival were analyzed.

RESULTS

The study involved 202 female patients with a median age of 52 years. Of these, 23.7% had IIIA, 65.3% had IIIB, and 10.8% had IIIC disease. Hormone receptor-positive disease was observed in 44.6% of patients, triple-negative breast cancer was observed in 24.8% of patients, and Human epidermal growth factor receptor 2 (HER2)-positive disease was observed in 30.7% of patients. Modified radical mastectomy (MRM) was performed in 88.1% of patients, 8.5% of patients remained inoperable, and 3.4% of patients declined surgery. Among the patients who underwent MRM, 36.5% of patients had a pCR. Patients who were operable and underwent MRM had complete resections and had negative margins. pCR was observed in 16% with hormone receptor-positive disease, in 45.6% with triple-negative breast cancer, and in 60.7% with HER2-positive disease. Grade 3 skin reactions were observed in 19.3% of patients. Postoperative wound morbidity requiring hospitalization was observed in 10.6% of patients. After a median follow-up of 42 months, the 4-year event-free survival and overall survival rates were 63.4% and 71.5%, respectively. HER2-positive patients who achieved a pCR had significantly improved event-free survival and overall survival.

CONCLUSIONS

Our study shows that using NACCRT can improve operability and survival outcomes in patients with inoperable LABC.

Preoperative Radio(Chemo)Therapy in Breast Cancer: Time to Switch the Perspective?

AIM

Radiation therapy represents, together with surgery and systemic treatment, the triad on which the current management of patients with breast cancer is based, achieving high control and survival rates. In recent years we have witnessed a (r)evolution in the conception of breast cancer treatment. The classic scheme of surgery followed by systemic treatment and radiotherapy is being subverted and it is becoming more and more frequent to propose the primary administration of systemic treatment before surgery, seeking to maximize its effect and favoring not only the performance of more conservative surgeries but also, in selected cases, increasing the rates of disease-free survival and overall survival. Radiotherapy is also evolving toward a change in perspective: considering preoperative primary administration of radiotherapy may be useful in selected groups. Advances in radiobiological knowledge, together with technological improvements that are constantly being incorporated into clinical practice, support the administration of increasingly reliable, precise, and effective radiotherapy, as well as its safe combination with antitumor drugs or immunotherapy in the primary preoperative context. In this paper, we present a narrative review of the usefulness of preoperative radiotherapy for breast cancer patients and the possibilities for its combination with other therapies.

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.

Neoadjuvant Concurrent Radiotherapy and Chemotherapy in Early Breast Cancer Patients: Long-Term Results of a Prospective Phase II Trial

Background: Neoadjuvant concurrent radiochemotherapy makes it possible to increase the breast conservation rate. This study reports the long term outcome of this treatment. Methods: From 2001 to 2003, 59 women with T_2-3 N_0-2 M₀ invasive breast cancer (BC) not amenable to upfront breast conserving treatment (BCS) were included in this prospective, non-randomized phase II study. Chemotherapy (CT) consisted of four cycles of continuous 5-FU infusion and Vinorelbine. Starting concurrently with the second CT cycle, normofractionated RT was delivered to the breast and LN. Breast surgery was then performed. Results: Median follow-up (FU) was 13 years [3-18]. BCS was performed in 41 (69%) patients and mastectomy in 18 patients, with pathological complete response rate of 27%. Overall and distant-disease free survivals rates at 13 years were 70.9% [95% CI 59.6-84.2] and 71.5% [95% CI 60.5-84.5] respectively. Loco regional and local controls rates were 83.4% [95% CI 73.2-95.0] and 92.1% [95% CI 83.7-100], respectively. Late toxicity (CTCAE-V3) was assessed in 51 patients (86%) with a median follow-up of 13 years. Fifteen presented grade 2 fibrosis (29.4%), 8 (15.7%) had telangiectasia, and 1 had radiodermatitis. Conclusions: This combined treatment provided high long-term local control rates with limited side-effects.

Study of pathological complete response rate with neoadjuvant concurrent chemoradiation with paclitaxel in locally advanced breast cancer

Background

Neoadjuvant concurrent chemoradiation (CTRT) is not widely practiced in breast cancers. The current study presents our experience with the use of neoadjuvant CTRT in patients with locally advanced breast cancers (LABC) treated at our center.

Methods

The study included all consecutive female patients with inoperable stage III LABC treated at Cancer Institute (W.I.A), Chennai, India, from December 2015 to September 2016. Data were collected retrospectively from the patients' case records. The impact of neoadjuvant CTRT on the pathological complete response (pCR) and survival was analyzed. Neoadjuvant chemotherapy consisted of 4 cycles of adriamycin and cyclophosphamide given either before or after 4 cycles of paclitaxel. All chemotherapy cycles were given once in 3 weeks. Concurrent radiotherapy was incorporated with 2 cycles of paclitaxel.

Results

The study included 100 patients with a median age of 49 years, among whom 9 (9%) had IIIA disease, 73 (73%) IIIB, and 18 (18%) had IIIC disease. The hormone receptor-positive disease was observed in 36 (36%) patients, triple-negative in 24 (24%), and Her2/neu positive disease in 40 (40%) patients. All patients were operable after completing the planned neoadjuvant treatments. Ninety-one out of 100 (91%) patients underwent modified radical mastectomy whereas 9 (9%) did not consent for surgery. Among the patients who underwent MRM, 34/91 (37.7%) patients had a pCR. Moreover, pCR was observed in 12/22 (54.5%) patients with triple-negative disease, 10/34 (29.4%) patients with hormone receptor-positive disease, and 12/35 (34.2%) patients with Her2/neu positive disease (P = 0.19). Most common morbidity observed was grade 3 skin reactions. The 2-year event-free survival and overall survival for the entire cohort was 73.1% and 88%, respectively.

Conclusion

Neoadjuvant CTRT is associated with a higher pCR rate than what has been reported with neoadjuvant chemotherapy alone. Further prospective studies are required to confirm our findings.

A systematic review of neo-adjuvant radiotherapy in the treatment of breast cancer

Introduction

The use of neo-adjuvant radiotherapy (NRT) has been proven effective at improving cancer related outcome measures, including overall-survival (OS) in the management of solid cancers. However, its utilisation in breast cancer has not been explored to the extent of neo-adjuvant chemotherapy (NAC). The evidence for the application of NRT in breast cancer is evaluated.

Methods

PubMed, Embase and the Cochrane Library databases were searched systematically in August 2020 for studies that addressed the role of NRT in the treatment of breast cancer. Studies were deemed eligible if they reported on objective outcome measurements of OS, disease free-survival (DFS) or pathological complete response (pCR) and attained a satisfactory quality assessment.

Findings

A total of 23 studies reported upon 3,766 patients who had received NRT of which 3,233 also received NAC concurrently (neo-adjuvant chemo-radiotherapy (NCRT)). The pCR values ranged from 14% to 42%, 5-year DFS 61.4% to 81% and 5-year OS 71.6% to 84.2%. Complications were confined to radiation dermatitis with no cases of implant loss reported during breast reconstruction. The application of NRCT alone showed no significant difference in OS or DFS compared to NCRT followed by surgery.

Interpretation

Numbers of patients receiving exclusively NRT is small. However, NCRT is oncologically safe with a low side-effect profile including preceding breast reconstruction. Potential benefits include precise cancer volume targeting, chemosensitisation, elimination of delays in adjuvant therapies and alternatives to chemotherapy in oestrogen receptor positive patients. These factors warrant further exploration within randomised controlled-trials.

Dopamine receptor D2 activation suppresses the radiosensitizing effect of aripiprazole via activation of AMPK

Drug repositioning has garnered attention as an alternative strategy to the discovery and development of novel anticancer drug candidates. In this study, we screened 321 FDA-approved drugs against nonirradiated and irradiated MCF-7 cells, revealing that aripiprazole, a dopamine receptor D2 (D2R) partial agonist, enhances the radiosensitivity of MCF-7 cells. Unexpectedly, D2R-selective antagonist treatment significantly enhanced the radiosensitizing effects of aripiprazole and prevented aripiprazole-induced 5' adenosine monophosphate-activated protein kinase (AMPK) phosphorylation. Direct AMPK activation with A769662 treatment blunted the radiosensitizing effects of aripiprazole. These results indicate that aripiprazole has potential as a radiosensitizing drug. Furthermore, prevention of D2R/AMPK activation might enhance these anticancer effects of aripiprazole in breast cancer cells.

Prospective results of concurrent radiation therapy and weekly paclitaxel as salvage therapy for unresectable locoregionally recurrent breast cancer

Purpose

To investigate the efficacy and toxicity of concurrent radiation therapy (RT) and paclitaxel in the treatment of unresectable locoregionally recurrent breast cancer (RBC) after mastectomy as primary treatment.

Methods

This was a prospective monocentric study of 51 patients (pts) diagnosed with unresectable locoregionally RBC after mastectomy and treated between 2008 and 2012. Radiotherapy (RT) was delivered at 60 Gy in 30 treatment fractions to recurrent sites. Chemotherapy was weekly paclitaxel of 50 mg/m² for 5 weeks. All pts. underwent clinical examination, CT or PET/CT every 3 months in first 2 years and then every 6 months. Tumor response was evaluated clinically and by CT using the RECIST criteria. Toxicity was assessed weekly during RT by the NCI common toxicity criteria (version 3.0).

Results

Fifty-one pts. with 61 recurrent sites were studied. The median age was 49 years. Sites of RBC were chest wall in 20 patients (32.8%), supraclavicular in 19 (31.1%), axilla in 11 (18.0%), and internal mammary lymph nodes in the remaining 11 (18.0%). RBC presented as single in 25 pts., multiple in 20 pts. and diffuse growth in 6 pts. Clinical response was observed in 47 pts. (92.2%), with 36 (70.6%) complete and 11 (21.6%) partial responses. Two patients (3.9%) presented with stable disease and 2 progressive disease. The cumulative local progression-free survival rate was 62.8% at 2 year and 53.0% at 5 years after treatment. No grade 4 toxicity was observed. Grade 3 radiation dermatitis and leukocytopenia were observed in 10 (19.6%) and 12 (23.5%) pts., respectively. One patient experienced grade 2 pneumonitis.

Conclusions

Concurrent RT and weekly paclitaxel could be an effective therapeutic option for unresectable locoregionally recurrent breast cancer after mastectomy with an acceptable toxicity profile.

Preoperative radiotherapy: A paradigm shift in the treatment of breast cancer? A review of literature

The standard of care for early-stage breast cancer (BC) consists of breast-conserving surgery followed by postoperative irradiation. Recently, the concept of changing the usual sequence of treatment components in BC RT has been investigated. Potential advantages of preoperative RT in BC include a possible tumor downstaging with improved surgical cosmetic outcomes, accurate tumor site identification and better target volume delineation. Furthermore, preoperative RT could serve as a tool for treatment stratification for de-escalation of treatments in the event of pathological complete response. The present literature review analyzed the available clinical data regarding the potential impact of preoperative RT. Overall, available clinical evidence of preoperative RT in BC remains limited, deriving mostly from retrospective case series. Nevertheless, the experiences prove the feasibility of the preoperative RT approach and confirm the efficacy in almost all analyzed studies, including experiences using higher prescription RT doses or RT in combination with systemic therapy.

Neoadjuvant concurrent chemoradiation in male breast cancer: Experience from a tertiary cancer center

BACKGROUND

Male breast cancers (MBC) account for 1% of all breast cancers. Neoadjuvant concurrent chemoradiation (CTRT) is not the standard of care for treating breast cancer. However, in our center, it has been routinely used in patients with locally advanced breast cancer to downsize the tumor and make it amenable to surgery.

AIM

This study was conducted to examine the clinical and pathological profile and outcomes of patients with MBC treated at our institute with neoadjuvant CTRT.

SETTINGS AND DESIGN

The study was conducted at a tertiary cancer center and was retrospective in nature.

MATERIALS AND METHODS

All MBC patients treated with neoadjuvant CTRT at our center between 2001 and 2016 were enrolled in the study. Data were retrospectively extracted from the patients' case records.

STATISTICAL ANALYSIS

Kaplan-Meier method was used for survival analysis and the outcome variables were compared using the log-rank test.

RESULTS

Thirty-one MBC patients who received neoadjuvant CTRT were analyzed in this study. The median age of the patients was 53 years. Stage IIB disease was observed in 8/31 (26%) patients, stage III in 20/31 (64%), and stage IV in 3/31 (10%) patients. There was no grade 3 or 4 toxicity due to CTRT. Surgery was performed in 29/31 (94%) patients and none of the patients had a pathological complete response. The median duration of follow-up was 95.3 months. The 8-year event-free survival and overall survival for stage IIB, III, and IV were 75%, 50%, and 0% and 87.5%, 69%, and 0%, respectively.

CONCLUSION

This is the first study to report on the use of neoadjuvant CTRT in MBC. Prospective evidence from phase-3 randomized controlled trials on the safety and efficacy of CTRT in breast cancer is required before its routine use can be recommended.

Preoperative breast radiation therapy: Indications and perspectives

Preoperative breast radiation therapy (RT) is not a new concept, but older studies failed to change practice. More recently, there has been interest in revisiting preoperative RT using modern techniques. This current perspective discusses the indications, summarises the published literature and then highlights current clinical trials, with particular attention to combining with novel drugs and optimising associated translational research.

Concurrent chemoradiotherapy for locally advanced breast cancer-time for a new paradigm?

BACKGROUND

In cases of locally advanced breast cancer (labc), preoperative ("neoadjuvant") therapy was traditionally reserved to render the patient operable. More recently, neoadjuvant therapy, particularly chemotherapy, is being used in patients with operable disease to increase the opportunity for breast conservation. Despite the increasing use of preoperative chemotherapy, rates of pathologic complete response, a surrogate marker for disease-free survival, remain modest in patients with locally advanced disease and particularly so when the tumour is estrogen or progesterone receptor-positive and her2-negative. A new paradigm for labc patients is needed. In other solid tumours (for example, rectal, esophageal, and lung cancers), concurrent chemoradiotherapy (ccrt) is routinely used in neoadjuvant and adjuvant treatment protocols alike.

RESULTS

The literature suggests that ccrt in labc patients with inoperable disease is associated with response rates higher than would be anticipated with systemic therapy alone.

CONCLUSIONS

Ongoing trials in this field are eagerly awaited to determine if ccrt should become the new paradigm.

Primary systemic therapy and whole breast irradiation for locally advanced breast cancer: a systematic review

The current management of locally advanced breast cancer (LABC) is based on tri-modality treatment including chemotherapy, radiotherapy and surgery. The concept of preoperative concurrent or sequential chemoradiation for LABC was initially reported more than a decade ago; however this concept did not gain popularity because of the low benefit/risk ratio and the lack of strong data supporting the concept. The purpose of the current systematic review was to explore the published data about preoperative chemoradiation (sequential and/or concurrent) using whole breast irradiation in terms of toxicity and outcome.

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.

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.

Weekly paclitaxel: an effective and well-tolerated treatment in patients with advanced breast cancer

The rationale for dose-dense weekly paclitaxel in the treatment of breast cancer is that more frequent delivery of more moderate doses may achieve greater efficacy than larger doses given less often through more sustained exposure of dividing tumor cells to cytotoxic drugs. Weekly paclitaxel has been used successfully in the treatment of advanced breast cancer, as single-agent therapy, in combination chemotherapy, with radiotherapy and with immunomodulating drugs, such as trastuzumab. Many of the patients in these studies have received previous chemotherapy regimens. Nevertheless, response rates with weekly paclitaxel up to 86% have been achieved with single-agent therapy, up to 87% with combination therapy and up to 100% when combined with radiotherapy. Paclitaxel given weekly together with the humanized monoclonal antibody against HER2, trastuzumab, has shown response rates of 50-82% in patients with aggressive HER2-positive tumors. Paclitaxel is associated with moderate toxicity. Its main dose-limiting toxicities are neutropenia and peripheral neuropathy, but these are generally manageable.

Preoperative paclitaxel and concurrent rapid-fractionation radiation for resectable pancreatic adenocarcinoma: toxicities, histologic response rates, and event-free outcome

PURPOSE

To evaluate the toxicity of a preoperative regimen of paclitaxel and concurrent external-beam radiation therapy, pancreaticoduodenectomy, and electron-beam intraoperative radiation therapy (EB-IORT) for patients with resectable pancreatic adenocarcinoma.

PATIENTS AND METHODS

Patients with localized, potentially resectable pancreatic adenocarcinoma were treated with 30 Gy external-beam radiation therapy and concomitant weekly 3-hour infusions of paclitaxel (60 mg/m(2)). Radiographic restaging was performed 4 to 6 weeks after chemoradiation, and patients with localized disease underwent pancreatectomy with EB-IORT.

RESULTS

Thirty-five patients completed chemoradiation; 16 (46%) experienced grade 3 toxicity. Four patients (11%) required hospitalization for dehydration due to grade 3 nausea and vomiting. Twenty (80%) of 25 patients who underwent surgery underwent pancreatectomy; EB-IORT was used in 13 patients. There were no histologic complete responses to preoperative therapy; 21% of specimens demonstrated more than 50% nonviable cells (grade 2b treatment effect). With a median follow-up period of 46 months, the 3-year overall survival rate with chemoradiation and pancreatectomy was 28%.

CONCLUSION

Preoperative paclitaxel-based concurrent chemoradiation is feasible. The toxicity of this regimen seems greater than that with fluorouracil. The histologic responses and survival are similar, suggesting no advantages to paclitaxel-based preoperative treatment.

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.

Risk of pneumonitis in breast cancer patients treated with radiation therapy and combination chemotherapy with paclitaxel

BACKGROUND

Some chemotherapy (CT) drugs, including taxanes, may enhance the effectiveness of radiation therapy (RT). However, combining these therapies may increase the incidence of radiation pneumonitis, a lung inflammation. In a retrospective cohort study, we evaluated the incidence of radiation pneumonitis in breast cancer patients treated with RT and standard adjuvant CT by use of doxorubicin (Adriamycin) and cyclophosphamide, with and without paclitaxel.

METHODS

Forty-one patients with breast cancer were treated with RT and adjuvant CT, including paclitaxel. Paclitaxel and RT (to breast-chest wall in all and lymph nodes in some) were delivered sequentially in 20 patients and concurrently in 21 patients. Paclitaxel was given weekly in some patients and every 3 weeks in other patients. The incidence of radiation pneumonitis was compared with that among patients in our database whose treatments did not include paclitaxel (n = 1286). The percentage of the lung volume irradiated was estimated. The Cox proportional hazards model was used to find covariates that may be associated with the observed outcomes. All P values were two-sided.

RESULTS

Radiation pneumonitis developed in six of the 41 patients. Three patients received paclitaxel concurrently with RT, and three received it sequentially (P =.95). The mean percentage of lung volume irradiated was 20% in patients who developed radiation pneumonitis and 22% in those who did not (P =.6). For patients treated with CT including paclitaxel, the crude rate of developing radiation pneumonitis was 14.6% (95% confidence interval [CI] = 5.6% to 29.2%). For patients treated with CT without paclitaxel, the crude rate of pneumonitis was 1.1% (95% CI = 0.2% to 2.3%). The difference between the crude rates with or without paclitaxel is highly statistically significant (P<.0001). The mean time to develop radiation pneumonitis in patients treated concurrently with RT and paclitaxel was statistically significantly shorter in patients receiving paclitaxel weekly than in those receiving it every 3 weeks (P =.002).

CONCLUSIONS

The use of paclitaxel and RT in the primary treatment of breast cancer should be undertaken with caution. Clinical trials with the use of combination CT, including paclitaxel plus RT, whether concurrent or sequential, must evaluate carefully the incidence of radiation pneumonitis.