RTOG 95-17, a Phase II trial to evaluate brachytherapy as the sole method of radiation therapy for Stage I and II breast carcinoma--year-5 toxicity and cosmesis

PURPOSE

Radiation Therapy Oncology Group (RTOG) 95-17, a Phase II trial to evaluate multicatheter brachytherapy (mCathBrachy) as the sole method of radiation therapy for Stage I-II breast cancer (BrCa), was the first cooperative group trial in North America to evaluate accelerated partial breast irradiation (APBI) and include patient-reported outcomes (PROs). This report presents the year-5 toxicity and cosmesis data.

METHODS AND MATERIALS

After lumpectomy and axillary dissection for invasive BrCa (tumor size <3cm with zero to three positive lymph nodes), 100 patients (pts), 98 evaluable, were treated (txed) with mCathBrachy from 1997 to 2000 with 34Gy administered twice daily in 10 high-dose-rate fractions or 45Gy in 3.5-6 days as a low-dose-rate implant to 1-2cm beyond the lumpectomy bed. The PROs and physician-reported outcomes of toxicity, cosmesis, and tx satisfaction at year-5 are reported here, defined as data submitted 54-78 months after tx.

RESULTS

Grade (G) 1-2 skin toxicity developed in 78% of the pts and G3 in 13% (no G4). The tx effects included skin dimpling/indentation (37%), fibrosis (45%), telangiectasias (45%), skin catheter marks (54%), and symptomatic fat necrosis (15%). Breast asymmetry was reported in 73%. Rates of excellent-to-good cosmesis were similar between PROs (66%) and radiation oncologists (68%). The PROs of tx satisfaction at year-5 was 75%.

CONCLUSIONS

RTOG 95-17 documents the year-5 skin toxicity and tx effects of mCathBrachy APBI, which are associated with PROs of good-to-excellent cosmesis and high tx satisfaction. This emphasizes the importance of PROs when assessing BrCa tx. National Surgical Adjuvant Breast and Bowel Project B39/RTOG 0413 will allow for definitive comparisons between APBI and whole breast radiation therapy.

Late toxicity and patient self-assessment of breast appearance/satisfaction on RTOG 0319: a phase 2 trial of 3-dimensional conformal radiation therapy-accelerated partial breast irradiation following lumpectomy for stages I and II breast cancer

PURPOSE

Late toxicities and cosmetic analyses of patients treated with accelerated partial breast irradiation (APBI) on RTOG 0319 are presented.

METHODS AND MATERIALS

Patients with stages I to II breast cancer ≤3 cm, negative margins, and ≤3 positive nodes were eligible. Patients received three-dimensional conformal external beam radiation therapy (3D-CRT; 38.5 Gy in 10 fractions twice daily over 5 days). Toxicity and cosmesis were assessed by the patient (P), the radiation oncologist (RO), and the surgical oncologist (SO) at 3, 6, and 12 months from the completion of treatment and then annually. National Cancer Institute Common Terminology Criteria for Adverse Events, version 3.0, was used to grade toxicity.

RESULTS

Fifty-two patients were evaluable. Median follow-up was 5.3 years (range, 1.7-6.4 years). Eighty-two percent of patients rated their cosmesis as good/excellent at 1 year, with rates of 64% at 3 years. At 3 years, 31 patients were satisfied with the treatment, 5 were not satisfied but would choose 3D-CRT again, and none would choose standard radiation therapy. The worst adverse event (AE) per patient reported as definitely, probably, or possibly related to radiation therapy was 36.5% grade 1, 50% grade 2, and 5.8% grade 3 events. Grade 3 AEs were all skin or musculoskeletal-related. Treatment-related factors were evaluated to potentially establish an association with observed toxicity. Surgical bed volume, target volume, the number of beams used, and the use of bolus were not associated with late cosmesis.

CONCLUSIONS

Most patients enrolled in RTOG 0319 were satisfied with their treatment, and all would choose to have the 3D-CRT APBI again.

NSABP B-43: A phase III clinical trial to compare trastuzumab (T) given concurrently with radiation therapy (RT) to RT alone for women with HER2+ DCIS resected by lumpectomy (Lx)

TPS666

Background: A significant amount of DCIS is ER-negative and/or overexpresses HER2. This study will test HER2-targeted therapy in DCIS. Among T-treated HER2+ patients (pts) with DCIS treated with a single dose of T, T is found in ductal aspirates and antibody-dependent cell-mediated cytotoxicity activity for HER2 is increased. T boosts the effectiveness of RT in breast cancer xenograft models and cell lines. T given during whole breast irradiation (WBI) may improve results for HER2+ DCIS treated with lumpectomy (Lx). A trial to examine this question will enhance the understanding of breast tumor biology, the prevention of such tumors, and could possibly extend breast-conserving surgery benefits for women with DCIS. Methods: After Lx for pure DCIS, each pt’s DCIS lesion is centrally tested for HER2 using ASCO/CAP guidelines. HER2+ pts are randomly assigned to receive 2 doses of T, 3 weeks apart during WBI or to WBI alone. Women ≥18 yrs with a margin-clear Lx for pure DCIS, with ECOG status 0/1 who are clinically or pathologically node negative are eligible. ER and/or PR status must be known before random assignment. Primary aims are to determine if T decreases ipsilateral breast cancer (IBC) recurrence, ipsilateral skin cancer recurrence, or ipsilateral DCIS. Secondary aims are to determine the benefit of T in preventing regional or distant recurrence and contralateral invasive breast cancer or DCIS. B-43 will determine if DFS, recurrence-free interval, and/or overall survival can be improved with the use of T. 2000 pts will be accrued over 7.9 yrs, with a definitive analysis of primary endpoints performed at163 IBC events (7.5 - 8 yrs after protocol initiation) with an 80% power to detect a hazard reduction of 36%, from 1.73 IBC events per 100 pt-yrs to 1.11 events per 100 pt-yrs. The 36% observed reduction in the hazard of IIBCR-SCR-DCIS on the T arm is based on a projection of 40% hazard reduction if the compliance were perfect, with a 10% noncompliance rate. As of 1-1-13, 1,127 pts have been randomized into the study. Support: PHS NCI-U10-CA-69651, -12027, and -P30-CA-14599 from the US NCI, and Genentech, Inc. Clinical trial information: NCT00769379.

Compliance with therapeutic guidelines in Radiation Therapy Oncology Group prospective gastrointestinal clinical trials

BACKGROUND

This report analyzes the adherence to radiation therapy protocol guidelines in contemporary Radiation Therapy Oncology Group (RTOG) gastrointestinal trials. We aim to provide insight into current standards and compliance of radiation therapy field design and administration.

METHODS

From 1994 to 2006, the Gastrointestinal Cancer Committee of the RTOG initiated and completed 15 phase I-III clinical trials utilizing radiation therapy in the multimodality treatment of gastrointestinal cancers. In each protocol, details for planning and executing radiation therapy were outlined and each protocol contained scoring criteria for these components of radiation therapy, characterized according to per-protocol, variation acceptable and deviation unacceptable. Review of treatment planning and implementation was performed in all studies following therapy completion.

RESULTS

Radiation therapy planning and implementation was reviewed in 2309 of 2312 (99.9%) patients. The mean rate of compliance over all for the 15 protocols was 65% (total of the 2309 analyzed patients). The mean variation acceptable rate was 21% whereas the mean deviation unacceptable rate was 5%. The mean "other" rate (no RT given or incomplete RT due to death, progression or refusal) was 8%. Two of the 15 trials (13%) had deviation unacceptable rates >10%. In four studies incorporating pre-treatment review of radiation therapy planning and treatment, compliance with protocol therapy was enhanced.

CONCLUSIONS

The fidelity of radiation planning and execution detailed in protocol to actual therapy is heterogeneous, with a mean per-protocol rate of 65%. As clinical trials evolve, available technology should permit efficient pre-treatment review processes, thus facilitating compliance to protocol therapy. These analyses should also permit prospective analysis of outcome measures by compliance to therapy.

Long-term outcome from RTOG 9517: A phase I/II study of accelerated partial breast irradiation (APBI) with mulitcatheter brachytherapy (MCT) following lumpectomy for early-stage breast cancer

147

Background: Comparison of APBI to whole breast irradiation post lumpectomy for breast conservation is ongoing in phase III trials. However, APBI has gained acceptance in clinical practice despite relatively limited long-term data. RTOG 9517 studied MCT, one of the earliest methods of APBI, and can uniquely provide long-term cancer outcomes. Methods: Eligibility was stage I/II unifocal breast cancer <3cm, invasive non-lobular histology without EIC, negative surgical margins, and 0-3 positive axillary nodes; no extracapsular extension. The target volume was the lumpectomy cavity plus a 2 cm radial and 1 cm ant/post margin. Low Dose Rate (LDR), 45 Gy in 3.5-5 day, or High Dose Rate (HDR) 34 Gy in 10 BID fractions over 5 days was delivered. A rapid dosimetry review was done to assure dose delivery per protocol. Systemic therapy was per physician’s discretion. The primary endpoint was HDR and LDR MCT reproducibility. This analysis focuses on ipsilateral breast failure (IBF), contralateral breast cancer events (CBE), regional (RF) and distant failure (DF) (cumulative incidence) disease-free (DFS), relapse-free (RFS), and overall survival (OS), (Kaplan-Meier). Results: The median follow up is 12.1 years (yr). 100 patients were accrued from 1997-2000; 98 were evaluable; 65 HDR and 33 LDR MCT. Median age was 62; 88% had T1 tumors; 12% T2; 81% p N0, 19% pN1; 77% ER and/or PR +; 19% ER - and PR -; 33 % received adjuvant chemotherapy and 64% antiendocrine therapy. There have been 6 IBF for a 10 yr rate of 6.2%; 2 IBF were outside the APBI field. There were 5 total RF for a 10 yr rate of 5.2%, respectively. There have been 5 CBE for a 10 yr rate of 4.2%. Failure patterns were: 4 isolated IBF, 1 isolated RF, 8 DF only, 1 IBF+RF, 1 IBF+RF+DF, 1 RF+CBE, 1 RF+DF, 3 CBE, and 1 CBE+DF (21 total failures). Eleven patients have developed DF; 8 have died of breast cancer, 22 have died from other causes. The 10 yr DFS, RFS and OS are 69.8%, 71.9%, and 78.0%, respectively. Conclusions: This multi-institutional phase II trial studying MCT-APBI continues to report durable local regional cancer control rates with long term follow-up. Supported by NCI U10 grants CA21661 and CA37422.

A phase III clinical trial to compare trastuzumab (T) given concurrently with radiation therapy (RT) to RT alone for women with HER2+ DCIS resected by lumpectomy (Lx): NSABP B-43

TPS657

Background: Asignificant amount of DCIS is ER negative and/or overexpresses HER2. This provides an opportunity to test molecular therapy in DCIS. In xenograft models and cell lines, T boosts RT effectiveness. In T-treated HER2+ patients, apoptosis occurs within 1 wk of single agent T use, with T found in ductal aspirates. Ample safety evidence for T exists. T given during whole breast irradiation (WBI) may improve results for Lx-resected HER2+ DCIS. A trial to examine this question will enhance the understanding of breast tumor biology and the prevention of such tumors and could possibly extend breast-conserving surgery benefits for women with DCIS. Methods: After Lx for pure DCIS, each patient’s DCIS lesion is centrally tested for HER2 by IHC analysis. HER2 2+ tumors undergo FISH analysis. HER2 3+ or FISH+ patients can be randomly assigned to 2 doses of T, 3 weeks apart during WBI or to WBI alone. Women ≥18 yrs. with a margin-clear Lx for pure DCIS, with ECOG status 0/1 who are and clinically or pathologically node negative are eligible. Centrally tested DCIS must be HER2 +. ER and/or PR status must be known before randomization. Primary aims are to determine if T decreases ipsilateral breast cancer recurrence, ipsilateral skin cancer recurrence, or ipsilateral DCIS. Secondary aims are to determine the benefit of T in preventing regional or distant recurrence and contralateral invasive breast cancer or DCIS. B-43 will determine if DFS, recurrence-free interval, and OS can be improved with the use of T. 2000 patients will be accrued over 7.9 yrs, with a definitive analysis of primary endpoints performed at163 ipsilateral breast cancer events (7.5 - 8 yrs. after protocol initiation) with an 80% power to detect a hazard reduction of 36%, from 1.73 ipsilateral breast cancer events per 100 pt-yrs to 1.11 events per 100 pt-yrs. The 36% observed reduction in the hazard of IIBCR-SCR-DCIS on the T arm is based on a projection of 40% hazard reduction if the compliance were perfect, with a 10% noncompliance rate. As of 12-31-11, 763 patients have been randomized. NCT00769379 Grant support: PHS NCI-U10-CA-69651, -12027, and NCI P30-CA-14599 from the US NCI and Genentech, Inc.

Randomized phase III trial to evaluate radiopharmaceuticals and zoledronic acid in the palliation of osteoblastic metastases from lung, breast, and prostate cancer: Report of RTOG 0517

TPS9150

Background: Skeletal related events (SREs) diminish quality of life (QOL) as well as overall survival (OS) in patients with bone metastases, a common event in breast, lung and prostate cancer. SREs can be reduced or delayed by the use of bisphosphonates. It is postulated that the radiopharmaceuticals, Strontium-89 (Sr89) and Samarium-153 (Sm153), when added to a bisphosphonate can decrease the incidence of SREs. Methods: RTOG 0517 randomized patients with breast, lung and prostate cancer and blastic bone metastases to either Zoledronic acid (ZA) alone or ZA plus a single standard dose of either Sr89 or Sm153. No limitations were placed on additional therapy such as chemotherapy or hormonal treatment. The projected median time to SRE [pathological bone fracture, spinal cord compression, surgery to bone, or radiation to bone] for the ZA arm was 10.4 months requiring 257 SRE events to detect a 33% relative reduction for the radiopharmaceutical arm in the time to development of an SRE with 90% power. Other study objectives included quality of life, pain control, OS and toxicity. Results: 261 patients (median age 68; 62% male; 55% prostate, 35% breast, 10% lung) were accrued from July 2006 through February 2011 (4.6 patients/month). Due to a lower than expected rate of SREs in the control (ZA) arm, the study was closed early and therefore did not reach the targeted accrual. 28 (17.4%) patients in the ZA arm and 27 (16.8%) in the radiopharmaceutical arm experienced an SRE. Median time to development of an SRE in the ZA and radiopharmaceutical arms was 11.60 and 16.74 months, respectively (p=.47). Median OS in the ZA arm and radiopharmaceutical arm was 15.95 and 11.18 months, respectively (p=0.12). Cox proportional hazards regression model showed that baseline characteristics, including gender, race, ethnicity, primary disease site or number of bone metastases, had no significant impact on OS. There was no difference in QOL parameters or toxicities between the two arms. Conclusion: Patients receiving ZA only experienced a much lower SRE rate than was hypothesized. The addition of Sr89 or Sm153 did not result in a difference in SREs, OS, or QOL

OT1-02-05: A Phase III Clinical Trial Comparing Trastuzumab Given Concurrently with Radiation Therapy to Radiation Therapy (RT) Alone for Women with HER2−Positive DCIS Resected by Lumpectomy: NSABP B-43

Background

Because a substantial portion of DCIS is ER negative and overexpresses HER2, therapy targeting this protein is a promising strategy for HER2−overexpressing DCIS.

Preclinical studies have shown that trastuzumab (T) boosts the effectiveness of RT in xenograft models and in cell lines with no detrimental effect on irradiated HER2−normal cells. Studies correlating clinical response with molecular markers in T-treated patients show that apoptosis occurs within 1 wk of starting singleagent T, with little effect on proliferation. Shorter duration treatments with this agent require investigation. Adjuvant trials using T during breast irradiation have already provided ample safety evidence. Will T administered during WBI improve lumpectomy + WBI results in women with HER2−positive DCIS? This trial will allow us to better understand the biology of breast cancer and its prevention and will extend the benefits of breast-conserving surgery for women with DCIS.

Trial Design: Post lumpectomy for DCIS without evidence of an invasive component, a central review of each patient's pure DCIS lesion is carried out for HER2 by IHC analysis. If the HER2 is 2+, FISH analysis is done, and patients whose tumors are HER2 3+ or FISH positive can be randomly assigned to receive 2 doses of T 3 wk apart during WBI or to receive WBI alone.

Eligibility criteria: Women 18 years or older with an ECOG status of 0 or 1 who have undergone a margin-clear lumpectomy for DCIS and whose tumors are clinically or pathologically node negative are eligible. DCIS must be HER2 positive by central testing. ER and/or PR status must be known before random assignment.

Specific aims: The primary aim is to determine if T given concurrently with WBI is more beneficial in preventing IBC recurrence, ipsilateral skin cancer recurrence, or ipsilateral DCIS compared with WBI alone for HER2−positive DCIS resected by lumpectomy. Secondary aims are to compare the possible benefit of T given during WBI to that of WBI alone in preventing regional or distant recurrence and contralateral invasive or DCIS breast cancer. B-43 will determine if invasive or DCIS DFS, recurrence-free interval, and OS can be improved with the addition of T to WBI. The effects of T on ovarian function in premenopausal women will also be assessed.

Statistical methods and accrual: Our design calls for accrual of 2000 patients during a 7.9-year period. As of May 31, 2011, 578 patients have been entered. A definitive analysis of primary endpoints will be performed when 163 ipsilateral breast cancer events occur (7.5 and 8 years after protocol initiation). This number of events affords 80% power to detect a hazard reduction of 36%, from 1.73 ipsilateral breast cancer events per 100 patient-years to 1.11 events per 100 patient-years. The 36% observed reduction in the hazard of IIBCR-SCR-DCIS on the T arm is based on a projection of 40% hazard reduction if the compliance were perfect, with a 10% noncompliance rate.

Supported by PHS grants NCI-U10-CA-69651, NCI-U10-CA-12027, and NCI P30-CA-14599 from the US NCI and Genentech, Inc.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr OT1-02-05.

Initial efficacy results of RTOG 0319: three-dimensional conformal radiation therapy (3D-CRT) confined to the region of the lumpectomy cavity for stage I/ II breast carcinoma

PURPOSE

This prospective study (Radiation Therapy Oncology Group 0319) examines the use of three-dimensional conformal external beam radiotherapy (3D-CRT) to deliver accelerated partial breast irradiation (APBI). Initial data on efficacy and toxicity are presented.

METHODS AND MATERIALS

Patients with Stage I or II breast cancer with lesions < or =3 cm, negative margins and with < or =3 positive nodes were eligible. The 3D-CRT was 38.5 Gy in 3.85 Gy/fraction delivered 2x/day. Ipsilateral breast, ipsilateral nodal, contralateral breast, and distant failure (IBF, INF, CBF, DF) were estimated using the cumulative incidence method. Mastectomy-free, disease-free, and overall survival (MFS, DFS, OS) were recorded. The National Cancer Institute Common Terminology Criteria for Adverse Events, version 3, was used to grade acute and late toxicity.

RESULTS

Fifty-eight patients were entered and 52 patients are eligible and evaluable for efficacy. The median age of patients was 61 years with the following characteristics: 46% tumor size <1 cm; 87% invasive ductal histology; 94% American Joint Committee on Cancer Stage I; 65% postmenopausal; 83% no chemotherapy; and 71% with no hormone therapy. Median follow-up is 4.5 years (1.7-4.8). Four-year estimates (95% CI) of efficacy are: IBF 6% (0-12%) [4% within field (0-9%)]; INF 2% (0-6%); CBF 0%; DF 8% (0-15%); MFS 90% (78-96%); DFS 84% (71-92%); and OS 96% (85-99%). Only two (4%) Grade 3 toxicities were observed.

CONCLUSIONS

Initial efficacy and toxicity using 3D-CRT to deliver APBI appears comparable to other experiences with similar follow-up. However, additional patients, further follow-up, and mature Phase III data are needed to evaluate the extent of application, limitations, and value of this particular form of APBI.

Respiratory organ motion and dosimetric impact on breast and nodal irradiation

PURPOSE

To examine the respiratory motion for target and normal structures during whole breast and nodal irradiation and the resulting dosimetric impact.

METHODS AND MATERIALS

Four-dimensional CT data sets of 18 patients with early-stage breast cancer were analyzed retrospectively. A three-dimensional conformal dosimetric plan designed to irradiate the breast was generated on the basis of CT images at 20% respiratory phase (reference phase). The reference plans were copied to other respiratory phases at 0% (end of inspiration) and 50% (end of expiration) to simulate the effects of breathing motion on whole breast irradiation. Dose-volume histograms, equivalent uniform dose, and normal tissue complication probability were evaluated and compared.

RESULTS

Organ motion of up to 8.8mm was observed during free breathing. A large lung centroid movement was typically associated with a large shift of other organs. The variation of planning target volume coverage during a free breathing cycle is generally within 1%-5% (17 of 18 patients) compared with the reference plan. However, up to 28% of V(45) variation for the internal mammary nodes was observed. Interphase mean dose variations of 2.2%, 1.2%, and 1.4% were observed for planning target volume, ipsilateral lung, and heart, respectively. Dose variations for the axillary nodes and brachial plexus were minimal.

CONCLUSIONS

The doses delivered to the target and normal structures are different from the planned dose based on the reference phase. During normal breathing, the dosimetric impact of respiratory motion is clinically insignificant with the exception of internal mammary nodes. However, noticeable degradation in dosimetric plan quality may be expected for the patients with large respiratory motion.

Phase I trial of bortezomib and concurrent external beam radiation in patients with advanced solid malignancies

PURPOSE

To determine the maximal tolerated dose of bortezomib with concurrent external beam radiation therapy in patients with incurable solid malignant tumors requiring palliative therapy.

METHODS AND MATERIALS

An open label, dose escalation, phase I clinical trial evaluated the safety of three dose levels of bortezomib administered intravenously (1.0 mg/m(2), 1.3 mg/m(2), and 1.6 mg/m(2)/ dose) once weekly with concurrent radiation in patients with histologically confirmed solid tumors and a radiographically appreciable lesion suitable for palliative radiation therapy. All patients received 40 Gy in 16 fractions to the target lesion. Dose-limiting toxicity was the primary endpoint, defined as any grade 4 hematologic toxicity, any grade ≥3 nonhematologic toxicity, or any toxicity requiring treatment to be delayed for ≥2 weeks.

RESULTS

A total of 12 patients were enrolled. Primary sites included prostate (3 patients), head and neck (3 patients), uterus (1 patient), abdomen (1 patient), breast (1 patient), kidney (1 patient), lung (1 patient), and colon (1 patient). The maximum tolerated dose was not realized with a maximum dose of 1.6 mg/m(2). One case of dose-limiting toxicity was appreciated (grade 3 urosepsis) and felt to be unrelated to bortezomib. The most common grade 3 toxicity was lymphopenia (10 patients). Common grade 1 to 2 events included nausea (7 patients), infection without neutropenia (6 patients), diarrhea (5 patients), and fatigue (5 patients).

CONCLUSIONS

The combination of palliative external beam radiation with concurrent weekly bortezomib therapy at a dose of 1.6 mg/m(2) is well tolerated in patients with metastatic solid tumors. The maximum tolerated dose of once weekly bortezomib delivered concurrently with radiation therapy is greater than 1.6 mg/m(2).

Early-stage BRCA2-linked breast cancer diagnosed in the first trimester of pregnancy associated with a hypercoagulable state

This patient was found to have a BRCA2 gene mutation. She underwent lumpectomy and axillary lymph node dissection without any evidence of lymph node metastasis. Systemic chemotherapy with doxorubicin and cyclophosphamide for four cycles was administered beginning in the second trimester. She was treated with prophylactic LMWH until delivery and then for 6 weeks postpartum. She delivered a healthy baby boy and, after a period of breast-feeding, underwent bilateral mastectomy with immediate reconstruction. She remains well and is expecting her second child. Prophylactic oophorectomy is planned after completion of this pregnancy.