DEGRO practical guidelines for radiotherapy of breast cancer IV: radiotherapy following mastectomy for invasive breast cancer

BACKGROUND AND PURPOSE

Since the last recommendations from the Breast Cancer Expert Panel of the German Society for Radiation Oncology (DEGRO) in 2008, evidence for the effectiveness of postmastectomy radiotherapy (PMRT) has grown. This growth is based on updates of the national S3 and international guidelines, as well as on new data and meta-analyses. New aspects were considered when updating the DEGRO recommendations.

METHODS

The authors performed a comprehensive survey of the literature. Data from recently published (meta-)analyses, randomized clinical trials and international cancer societies' guidelines yielding new aspects compared to 2008 were reviewed and discussed. New aspects were included in the current guidelines. Specific issues relating to particular PMRT constellations, such as the presence of risk factors (lymphovascular invasion, blood vessel invasion, positive lymph node ratio >20 %, resection margins <3 mm, G3 grading, young age/premenopausal status, extracapsular invasion, negative hormone receptor status, invasive lobular cancer, size >2 cm or a combination of ≥ 2 risk factors) and 1-3 positive lymph nodes are emphasized.

RESULTS

The evidence for improved overall survival and local control following PMRT for T4 tumors, positive resection margins, >3 positive lymph nodes and in T3 N0 patients with risk factors such as lymphovascular invasion, G3 grading, close margins, and young age has increased. Recently identified risk factors such as invasive lobular subtype and negative hormone receptor status were included. For patients with 1-3 positive lymph nodes, the recommendation for PMRT has reached the 1a level of evidence.

CONCLUSION

PMRT is mandatory in patients with T4 tumors and/or positive lymph nodes and/or positive resection margins. PMRT should be strongly considered in patients with T3 N0 tumors and risk factors, particularly when two or more risk factors are present.

Hypofractionation with simultaneous integrated boost for early breast cancer: results of the German multicenter phase II trial (ARO-2010-01)

PURPOSE

To evaluate the feasibility of hypofractionation with SIB in all settings in Germany to prepare a multicenter treatment comparison.

METHODS

Eligible patients had histopathologically confirmed breast cancer operated by BCS. Patients received WBI 40.0 Gy in 16 fractions of 2.5 Gy. A SIB with 0.5 Gy per fraction was administered to the tumor bed, thereby giving 48.0 Gy in 16 fractions to the boost-PTV sparing heart, LAD, lung, contralateral breast. The primary study objective was feasibility, administration of specified dose in 16 fractions within 22-29 days with adherence to certain dose constraints (heart; LAD; contralateral breast); secondary endpoints were toxicity, QoL.

RESULTS

151 patients were recruited from 7 institutions between 07/11-10/12. 10 patients met exclusion criteria prior to irradiation. All but two patients (99%) received the prescribed dose in the PTVs. Adherence to dose constraints and time limits was achieved in 89% (95% CI 82% to 93%). 11 AE were reported in 10 patients; five related to concurrent endocrine therapy. Two of the AEs were related to radiotherapy: grade 3 hot flushes in two cases. QoL remained unchanged.

CONCLUSION

Hypofractionation with a SIB is feasible and was well tolerated in this study.

Merkel-Zell-Karzinom

Merkel cell carcinoma (cutaneous neuroendocrine carcinoma) is an uncommon, highly malignant, neuroendocrine skin tumour. Typically, the primary is a fast-growing tough dermal nodule that is characterized histologically by uniform round cells with a small cytoplasmic rim. The tumour cells express the cytokeratins 8, 18, 19, 20, neurofilament, synaptophysin, chromogranin, and neuron-specific enolase. A high frequency of local recurrences (25-77%) and lymph-node metastases (50%) are characteristic features of Merkel cell carcinoma. The 5-year survival rate is 30-74%. Merkel cell carcinomas are highly radiosensitive. Thus, besides surgical methods, radiation should be included into the treatment concept in every stage. We present four cases of Merkel cell carcinoma with different courses for a review-like discussion of this disease giving instructions for rapid diagnosis and effective therapy.

DEGRO practical guidelines: radiotherapy of breast cancer I: radiotherapy following breast conserving therapy for invasive breast cancer

Background and purpose

The aim of the present paper is to update the practical guidelines for postoperative adjuvant radiotherapy of breast cancer published in 2007 by the breast cancer expert panel of the German Society for Radiooncology (Deutsche Gesellschaft für Radioonkologie, DEGRO). The present recommendations are based on a revision of the German interdisciplinary S-3 guidelines published in July 2012.

Methods

A comprehensive survey of the literature concerning radiotherapy following breast conserving therapy (BCT) was performed using the search terms “breast cancer”, “radiotherapy”, and “breast conserving therapy”. Data from lately published meta-analyses, recent randomized trials, and guidelines of international breast cancer societies, yielding new aspects compared to 2007, provided the basis for defining recommendations according to the criteria of evidence-based medicine. In addition to the more general statements of the DKG (Deutsche Krebsgesellschaft), this paper addresses indications, target definition, dosage, and technique of radiotherapy of the breast after conservative surgery for invasive breast cancer.

Results

Among numerous reports on the effect of radiotherapy during BCT published since the last recommendations, the recent EBCTCG report builds the largest meta-analysis so far available. In a 15 year follow-up on 10,801 patients, whole breast irradiation (WBI) halves the average annual rate of disease recurrence (RR 0.52, 0.48–0.56) and reduces the annual breast cancer death rate by about one sixth (RR 0.82, 0.75–0.90), with a similar proportional, but different absolute benefit in prognostic subgroups (EBCTCG 2011).

Furthermore, there is growing evidence that risk-adapted dose augmentation strategies to the tumor bed as well as the implementation of high precision RT techniques (e.g., intraoperative radiotherapy) contribute substantially to a further reduction of local relapse rates. A main focus of ongoing research lies in partial breast irradiation strategies as well as WBI hypofractionation schedules. The potential of both in replacing normofractionated WBI has not yet been finally clarified.

Conclusion

After breast conserving surgery, no subgroup even in low risk patients has yet been identified for whom radiotherapy can be safely omitted without compromising local control and, hence, cancer-specific survival. In most patients, this translates into an overall survival benefit.

Analysis of bevacizumab-based preoperative radiochemotherapy in patients with locally advanced rectal cancer on surgery-associated spectrum of complications

BACKGROUND

Preoperative radiochemotherapy (RCT) is a standard of care for patients with locally advanced rectal cancer (LARC; stages II and III). Results of our phase II study (BevXelOx-RT) have shown that this regimen is feasible but without a significant improvement of pathological complete response. Whether preoperatively administered bevacizumab, due to its specific toxicity profile, leads to increased rates of surgical complications is currently a subject for debate. This analysis focusses on the surgery-associated spectrum of complications.

METHODS

Data from 62 patients with rectal cancer (uT3-4; N0/1, M0) of the phase II trial were analyzed. Patients received radiotherapy (50.4/1.8 Gy fractions), simultaneous bevacizumab 5 mg/kg (d1, d15, d29), and capecitabine 825 mg/m(2) twice daily (d1-14, d22-35), oxaliplatin 50 mg/m(2) (d1, d8, d22, d29). Four to six weeks after RCT, surgical resection was performed.

RESULTS

Overall, 69/69 patients underwent surgery, and 66 (95.7 %) patients had R0 resection. Surgery was mainly conducted (in 66 %) by highly experienced surgeons (>20 resections of rectal cancer/year) with differences between the institutions due to the operative procedures but without effects on the rate of R0 resection or complications. The average duration of surgery was 239 min (±10). Frequency of multivisceral resections (11 %), intraoperative (8 %) and postoperative (43 %) complications were all in the expected range. In particular, we did not observe an increased rate of postoperative bleedings (3 %). The postoperative mortality rate was 0 %.

CONCLUSIONS

Quantity and the kind of surgery-associated spectrum of complications followed by a preoperative bevacizumab-containing RCT regimen in patients with LARC were in line with comparable trials of bevacizumab-based approaches.

The Aryl Hydrocarbon Receptor Nuclear Translocator (ARNT/HIF-1β) is influenced by hypoxia and hypoxia-mimetics

BACKGROUND

The Aryl Hydrocarbon Receptor Nuclear Translocator (ARNT, HIF-1β) is a member of the basic-Helix-Loop-Helix PER/ARNT/SIM (bHLH/PAS) protein family and a vital transcriptional regulator regarding development and physiological adaptation processes. ARNT is discussed to be linked with cancer, and other diseases. ARNT is known to be translocated into the cell nucleus, where accumulation of the protein takes place. ARNT is a heterodimerisation partner of the xenobiotic ligand activated Aryl Hydrocarbon Receptor (AhR), the Single Minded proteins (SIM), the cardiovascular helix-loop-helix factor 1 and the Hypoxia Inducible Factor proteins (HIF-α). ARNT is obligatory for HIF-1, HIF-2 and HIF-3 binding to DNA. Whereas degradation of the HIF-α subunits is suppressed by hypoxia, ARNT is generally regarded as constitutively expressed in excess within the cell, and stabilisation is commonly thought to be oxygen-independent. However, we provide evidence that the regulation of ARNT is far more complex. The aim of our study was to reevaluate the regulation of ARNT expression.

METHODS

We examined cell lines of different origin like MCF-7 and T47D (human breast cancer), HeLa (human cervix carcinoma), Hep3B and HepG2 (human hepatoma), Kelly (human neuroblastoma), REPC (human kidney) and Cos7 (primary primate kidney) cells. We used immunoblot analysis, densitometry, RT-PCR and transient transfection.

RESULTS AND CONCLUSION

Our results show that ARNT protein levels are influenced by hypoxia and hypoxia mimetics such as cobalt(II)-chloride (CoCl2) and dimethyloxalylglycine (DMOG) in a cell line specific manner. We demonstrate that this effect might be triggered by HIF-1α which plays an important role in the process of stabilizing ARNT in hypoxia.

The prognostic value of tumor necrosis in patients undergoing stereotactic radiosurgery of brain metastases

Background

This retrospective study investigated the outcome of patients with brain metastases after radiosurgery with special emphasis on prognostic impact of visible intratumoral necrosis on survival and local control.

Methods

From 1998 through 2008, 149 patients with brain metastases from solid tumors were treated with stereotactic radiotherapy at Luebeck University. Median age was 58.4 years with 11%, 78%, 10% in recursive partitioning analysis (RPA) classes I, II, III, respectively. 70% had 1 metastasis, 29% 2-3 metastases, 2 patients more than 3 metastases, 71% active extracranial disease. Median volume of metastatic lesions was 4.7 cm³, median radiosurgery dose 22 Gy (single fraction). 71% of patients received additional whole-brain irradiation (WBI). All patients were analyzed regarding survival, local, distant failure and prognostic factors, side effects and changes in neurologic symptoms after radiotherapy. The type of contrast-enhancement in MR imaging was also analyzed; metastatic lesions were classified as containing necrosis if they appeared as ring-enhancing with central areas of no or minimal contrast enhancement.

Results

Median survival was 7.0 months with 1-year and 5-year survival rates of 33% and 0.4%, respectively. Tumor necrosis (ring-enhancement) was visible on pretreatment MRI scans in 56% of all lesions and lesions with necrosis were larger than non-necrotic lesions (6.7 cm³ vs. 3.2 cm³, p = 0.01). Patients with tumor necrosis had a median survival of 5.4 months, patients without tumor necrosis 7.2 months. Local control rate in the irradiated volume was 70%, median survival without local failure 17.8 months. Control in the brain outside the irradiated volume was 60%, median survival without distant failure 14.0 months. Significant prognostic factors for overall survival were KPS (p = 0.001), presence of tumor necrosis on pretreatment MRI (p = 0.001) with RPA-class and WBI reaching marginal significance (each p = 0.05). Prognostic impact of tumor necrosis remained significant if only smaller tumors with a volume below 3.5 cm³ (p = 0.03). Side effects were rare, only one patient suffered from serious acute side effects.

Conclusions

Results of this retrospective study support that stereotactic radiotherapy is an effective treatment option for patients with metastatic brain lesions. The prognostic impact of visible tumor necrosis (ring-enhancement) on pretreatment MRI scans should be further investigated.

Phase II trial of preoperative radiochemotherapy with concurrent bevacizumab, capecitabine and oxaliplatin in patients with locally advanced rectal cancer

BACKGROUND

Preoperative radiochemotherapy (RCT) with 5-FU or capecitabine is the standard of care for patients with locally advanced rectal cancer (LARC). Preoperative RCT achieves pathological complete response rates (pCR) of 10-15%. We conducted a single arm phase II study to investigate the feasibility and efficacy of addition of bevacizumab and oxaliplatin to preoperative standard RCT with capecitabine.

METHODS

Eligible patients had LARC (cT3-4; N0/1/2, M0/1) and were treated with preoperative RCT prior to planned surgery. Patients received conventionally fractionated radiotherapy (50.4 Gy in 1.8 Gy fractions) and simultaneous chemotherapy with capecitabine 825 mg/m2 bid (d1-14, d22-35) and oxaliplatin 50 mg/m2 (d1, d8, d22, d29). Bevacizumab 5 mg/kg was added on days 1, 15, and 29. The primary study objective was the pCR rate.

RESULTS

70 patients with LARC (cT3-4; N0/1, M0/1), ECOG < 2, were enrolled at 6 sites from 07/2008 through 02/2010 (median age 61 years [range 39-89], 68% male). At initial diagnosis, 84% of patients had clinical stage T3, 62% of patients had nodal involvement and 83% of patients were M0. Mean tumor distance from anal verge was 5.92 cm (± 3.68). 58 patients received the complete RCT (full dose RT and full dose of all chemotherapy). During preoperative treatment, grade 3 or 4 toxicities were experienced by 6 and 2 patients, respectively: grade 4 diarrhea and nausea in one patient (1.4%), respectively, grade 3 diarrhea in 2 patients (3%), grade 3 obstipation, anal abscess, anaphylactic reaction, leucopenia and neutropenia in one patient (1.4%), respectively. In total, 30 patients (46%) developed postoperative complications of any grade including one gastrointestinal perforation in one patient (2%), wound-healing problems in 7 patients (11%) and bleedings in 2 patients (3%). pCR was observed in 12/69 (17.4%) patients. Pathological downstaging (ypT < cT and ypN ≤ cN) was achieved in 31 of 69 patients (44.9%). All of the 66 operated patients had a R0 resection. 47 patients (68.1%) underwent sphincter preserving surgery.

CONCLUSIONS

The addition of bevacizumab and oxaliplatin to RCT with capecitabine was well tolerated and did not increase perioperative morbidity or mortality. However, the pCR rate was not improved in comparison to other trials that used capecitabine or capecitabine/oxaliplatin in preoperative radiochemotherapy.

Radiation induced G2/M block and apoptosis in two human sarcoma cell lines with different p53 gene status

We investigated a wild-type (wt) p53 rhabdomyosarcoma (A-204) and a mutated (mt p53) undifferentiated sarcoma cell line (US8-93) for their response to X-rays. The observation period was 0 to 96 h after irradiation. Both cell lines showed a strikingly delayed G2/M arrest and an induction of apoptosis after irradiation. Compared with the cell line A-204 (wt p53), the cell line US8-93 (mt p53) revealed a stronger G2/M arrest. In agreement with this, in terms of viability as well as the rate of apoptosis, A-204 (wt p53) showed a stronger response to irradiation than US8-93 (mt p53). We suggest that the different p53 gene status might be the cause for a different response to irradiation.

Concurrent chemoradiation of metastases with capecitabine and oxaliplatin and 3D-CRT in patients with oligometastatic colorectal cancer: results of a phase I study

BACKGROUND

Local control appears to be an important treatment aim in patients with limited metastases (oligometastases) of colorectal cancer (CRC). Those patients show a favourable prognosis, if--in addition to the local effective treatment--an occurrence of new metastases may also be postponed by effective systemic therapy. The purpose of this dose escalation phase I study was to establish the efficacy of local radiotherapy (RT) of oligometastatic CRC with a concurrent standard chemotherapy regimen.

METHODS

Patients with first-, second- or third-line therapy of oligometastatic CRC (1-3 metastases or local recurrence plus max. 2 metastases) received capecitabine (825 mg/m²/d BID d 1-14; 22-35) and oxaliplatin (50 mg/m² d 1, 8, 22, 29). 3D-conformal RT of all metastatic lesions was delivered in 2.0 Gy up to 36 Gy to 50 Gy (3 dose levels). Primary endpoint was the maximal tolerable dose (MTD) of RT defined as the level at which two or more of six patients experienced dose-limiting toxicity (DLT).

RESULTS

Between 09/2004 and 08/2007, 9 patients (7 male, 2 female, 50-74 years) were enrolled, 6 patients treated at dose level 1 (36 Gy), 3 patients at dose level 2 (44 Gy). 1 patient from the first cohort experienced DLT (oxaliplatin-related hypersensitivity reaction). No radiation-induced DLT occurred. 6/9 patients achieved objective response (partial remission). One year after initiation, all patients were alive, 6 patients survived (16 to 54 months) patients died of tumor progression (14 to 23 months). The phase II part of the trial had to be closed due to recruitment failure.

CONCLUSIONS

Local 3D-CRT to metastatic lesions in addition to standard chemotherapy was feasible, DLT was not documented. 3/9 patients survived for a period of 3.5 to 4.4 years (time at the last evaluation). Radiotherapy of metastatic lesions should be incorporated into subsequent trials.

Margins! Margins. Margins? How Important Is Margin Status in Breast-Preserving Therapy?

Margin status is surely a prognostic factor in patients undergoing breast-conserving therapy, but its impact is probably overestimated in case of adequate adjuvant radiotherapy. Radiotherapy improves local control after excision of the primary tumor in all subgroups of patients. There is, in contrast, no evidence that a certain margin width or a re-resection improves local control.