Summary of Meta-Analyses Dealing with Single-Row versus Double-Row Repair Techniques for Rotator Cuff Tears

Background:

Several meta-analyses of randomized clinical trials have been performed to analyze whether double-row (DR) rotator cuff repair (RCR) provides superior clinical outcomes and structural healing compared to single-row (SR) repair. The purpose of this study was to sum up the results of meta-analysis comparing SR and DR repair with respect on clinical outcomes and re-tear rates.

Methods:

A literature search was undertaken to identify all meta-analyses dealing with randomized controlled trials comparing clinical und structural outcomes after SR versus DR RCR.

Results:

Eight meta-analyses met the eligibility criteria: two including Level I studies only, five including both Level I and Level II studies, and one including additional Level III studies. Four meta-analyses found no differences between SR and DR RCR for patient outcomes, whereas four favored DR RCR for tears greater than 3 cm. Two meta-analyses found no structural healing differences between SR and DR RCR, whereas six found DR repair to be superior for tears greater than 3 cm tears.

Conclusion:

No clinical differences are seen between single-row and double-row repair for small and medium rotator cuff tears after a short-term follow-up period with a higher re-tear rate following single-row repairs. There seems to be a trend to superior results with double-row repair in large to massive tear sizes.

[Seasonal distribution of clinical case codes (DOC study)]

OBJECTIVES

The German diagnosis-related groups remuneration system (G-DRG) was implemented in 2004 and patient-related diagnoses and procedures lead to allocation to specific DRGs. This system includes several codes, such as case mix (CM), case mix index (CMI) and number of cases. Seasonal distribution of these codes as well as distribution of diagnoses and DRGs may lead to logistical consequences for clinical management.

METHODS

From 2004 to 2013 all the main diagnoses and DRGs for inpatients were recorded. Monthly and seasonal distributions were analyzed using ANOVA.

RESULTS

The average monthly number of cases was 265 ± 25 cases, the average CM was 388.50 ± 51.75 and the average CMI was 1.46 ± 0.15 with no significant seasonal differences (p > 0.1). Concussion was the most frequently occurring main diagnosis (3739 cases) followed by fractures of the humeral head (699). Significant distribution differences could be shown for humeral head fractures in monthly (p = 0.018) and seasonal comparisons (p = 0.006) with a maximum in winter. Radius (p = 0.01) and ankle fractures (p ≤ 0.001) also occurred most frequently in winter. Non-bony lesions of the shoulder were significantly less in spring (p = 0.04). The DRGs showed no evidence of a monthly or seasonal clustering (p > 0.1).

CONCLUSION

The significant clustering of injuries in specific months and seasons should lead to logistic consequences (e.g. operating room slots, availability of nursing and anesthesia staff). For a needs assessment the analysis of main diagnoses is more appropriate than DRGs.

[Multiplanar reconstruction with mobile 3D image intensifier. Surgical treatment of proximal humerus fractures]

PURPOSE

The aim of this study was to analyze the applicability and advantages of the intraoperative use of a mobile 3D C-arm with multiplanar imaging for surgery of acute proximal humerus fractures.

MATERIALS AND METHODS

In this study 20 patients (11 female, 9 male, median age 70 years, range 35-91 years) with dislocated proximal humerus fractures (6 with 2 segments, 10 with 3 segments and 4 with 4 segments) were included. Preoperatively 3D scanning was performed and a reevaluation of the fracture in comparison to the plain radiographs was performed. After operative treatment another scan was performed to evaluate technical complications.

RESULTS

In comparison to the multiplanar reconstructions fracture morphology could not be correctly detected in 5 out of the 20 cases with plain radiographs. The preoperative image quality of the multiplanar reconstructions showed a significantly better assessment in comparison to the image quality with osteosynthesis (p < 0.05). The screws had to be replaced in 5 of the 20 patients.

CONCLUSION

Intraoperative 3D imaging with mobile image intensifier enables an accurate analysis of fracture morphology. Furthermore a quasi real time preoperative planning, evaluation of reduction and implant position with immediate operative relevance can be realized.

Feasibility and first long-term results after laparoscopic rectal segment resection and vaginal specimen retrieval for deep infiltrating endometriosis

INTRODUCTION

Radical resection of deep infiltrating endometriosis (DIE), including bladder and bowel resection, provides relief from pain in symptomatic patients. The laparoscopic approach to treatment is well established for bowel resection but normally requires additional abdominal incisions for specimen retrieval. Here we describe our technique of laparoscopically assisted rectal resection and transvaginal specimen retrieval (LARRT) and provide follow-up information on pain scores and complications.

MATERIALS AND METHODS

Retrospective observational monocentric study on all DIE patients with rectal infiltration treated between 2008 and 2010 with LATRR at our department. Follow-up was obtained for at least 3 years, including baseline 1-year and 3-year pain scores.

RESULTS

We identified four patients undergoing LARRT available for follow-up. DIE was confirmed by histology in all cases. There were no intraoperative complications. Two patients had transient postoperative urinary retention, one patient developed recto-vaginal fistula and required transient colostomy. One patient suffered from persistent vaginal dryness. All patients, however, reported persistent pain relief, including at the end of follow-up period.

CONCLUSION

LARRT is a feasible variation of laparoscopic bowel resection for DIE with rectal infiltration. In our study it has promising results with respect to pain control. Larger studies will, however, be required to determine the safety of this procedure.

Abstract P3-12-09: The prevalence and quantity of circulating tumor cells (CTCs) after adjuvant chemotherapy with and without anthracyclines in patients with HER2-negative early breast cancer (EBC)

Background: The use of anthracycline based chemotherapy in early breast cancer (EBC) patients has been well established. However, adverse effects like cardiotoxicity and efficacy in certain subgroups continue to be subjects of discussion. Based on data suggesting a limited benefit of anthracyclines in HER2-negative patients, the German SUCCESS C study randomly assigned patients with EBC to be treated with either anthracycline-containing or anthracycline-free chemotherapy. Since the prognostic value of CTCs in EBC has already been demonstrated in several trials, we compared the prevalence of CTCs after the completion of chemotherapy between both treatment arms.

Methods: The SUCCESS C trial was a randomized, open-label, Phase III study comparing disease free survival (DFS) in patients with HER2-negative EBC. Treatments were either 3 cycles epirubicin, 5-fluorouracil and cyclophosphamide followed by 3 cycles of docetaxel (FEC–DOC), or 6 cycles of an anthracycline-free regimen with docetaxel and cyclophosphamide (DOC-C). The CTC status at chemotherapy cycle 6 was prospectively evaluated using the FDA-approved CellSearch System (Veridex, USA).

Results: Data on CTC status after chemotherapy are available for 1757 patients. Overall, CTCs were found in 220 (12.5%) patients (median 1, range 1 – 18 CTCs). One CTC was detected in 123 (55.9%), two CTCs in 53 (24.1%), three to five CTCs in 37 (16.8%), and more than five CTCs in 7 (3.2%) of these patients. Univariate analyses revealed that CTC prevalence was not significantly associated with tumor size (pT1, pT2, pT3, pT4), nodal stage (pN0, pN1, pN2, pN3), grading (G1, G2, G3), histological type (invasive ductal, invasive lobular, other), estrogen-receptor status, or progesterone-receptor status (Chi-square tests, all p &gt; 0.1). There was no significant difference with respect to the prevalence of CTCs after chemotherapy between the two treatment arms (Chi-square test, p = 0.23), as CTCs were detected in 11.6% (103 out of 889) of patients treated with the anthracycline-containing chemotherapy regimen and in 13.5% (117 out of 868) of patients treated with the anthracycline-free chemotherapy regimen. In addition, there was no significant difference between the two treatment arms with regard to the number of CTCs detected after chemotherapy in CTC-positive patients (FEC-DOC: median = 1, range 1 – 18; DOC-C: median = 1, range 1 – 8; Mann-Whitney U test, p = 0.30).

Conclusions: The comparable prevalence and number of CTCs after the completion of chemotherapy may indicate that anthracycline-free chemotherapy is not inferior to anthracycline-containing chemotherapy in this study. This however, has to be confirmed by survival analyses, which will be available in 2014.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P3-12-09.

[Is distal femoral replacement an adequate therapeutic option after complex fractures of the distal femur?]

BACKGROUND

Modular distal femur replacements originally were developed for reconstructing a full weight-bearing and functional extremity after resection of primary bone tumours with large bony defects located in proximity to joints. The aim of this study was to examine the use of the modular distal femur replacements for complex fractures and severe post-traumatic sequelae of the distal femur in context to comparable studies.

PATIENTS AND METHODS

Fourteen patients with complex fractures or post-traumatic sequelae and extensive bone defects requiring distal femur replacement were analysed retrospectively. Median age of the patients at the time of distal femoral replacement was 77 years and median follow-up interval was 27 months. Median follow-up was 27.0 (IQB 13.5-37.5) months (range 10-49 months).

RESULTS

The indication for distal femur replacement was a periprosthetic fracture in three cases. Three further periprosthetic fractures were treated with a megaendoprosthesis after failure of osteosynthesis. In eight patients a megaendoprosthesis was implanted due to complications following ostheosynthesis for distal femoral fractures. Distal femoral arthroplasty was performed as a two-stage procedure in five patients with implant-associated infections. A lateral approach was used in six patients and a medial arthrotomy was conducted in eight patients. The median Knee Society score (KSS) improved significantly from 20.0 (IQB 7.5-30.0) points preoperatively to 80.0 (IQB 62.3-89.0) points at follow-up (p < 0.001). Complications requiring surgical intervention were documented in seven of 14 patients (50 %). In two patients wound-healing disorders and superficial infections necessitated surgery. In one patient a rupture of the patellar tendon was diagnosed. This patient subsequently also sustained a periprosthetic fracture. Another patient developed early aseptic loosening of the femoral component. The most common complication was a periprosthetic fracture in four patients. Three patients died for reasons not related to distal femoral replacement.

CONCLUSION

Distal femoral replacement is an important option in reconstituting a full weight-bearing and functional lower extremity after complex fractures and post-traumatic sequelae with massive bone destruction. Particularly elderly patients regain ambulatory ability in the vast majority of cases. The relatively high complication rate demands very thorough preoperative planning as well as prompt allocation of extensive surgical procedures in the case of an adverse event.

Participation in the SUCCESS-A Trial Improves Intensity and Quality of Care for Patients with Primary Breast Cancer

The SUCCESS-A trial is a prospective, multicenter, phase III clinical trial for high-risk primary breast cancer. It compares disease-free survival after randomization in patients treated with fluorouracil, epirubicin and cyclophosphamide followed by 3 cycles of docetaxel (FEC-D) with that of patients treated with 3 cycles of FEC followed by 3 cycles of gemcitabine and docetaxel (FEC-DG). After a second randomization patients were treated with zoledronate for 2 or 5 years. A total of 251 centers took part in the trial and 3754 patients were recruited over a period of 18 months which ended in March 2007. In a questionnaire-based survey we investigated the impact of enrollment in the trial on patient care, the choice of chemotherapy protocol and access to current oncologic information as well as overall satisfaction in the respective centers. Analysis of the 78 questionnaires returned showed that 40 % of the centers had never previously enrolled patients with these indications in clinical studies. Prior to participating in the study, 4 % of the centers prescribed CMF or other protocols in patients with high-primary breast cancer risk, 46 % administered anthracycline-based chemotherapy and 50 % gave taxane-based chemotherapy. Around half of the participating centers noted that intensity of care and overall quality of care became even better and that access to breast cancer-specific information improved through participation in the trial. After their experience with the SUCCESS-A trial, all of the centers stated that they were prepared to enroll patients in clinical phase III trials again in the future. These data indicate that both patients and physicians benefit from clinical trials, as enrollment improves treatment strategies and individual patient care, irrespective of study endpoints.

Abstract P2-10-25: Prognostic value of relative change in tumor marker CA 27.29 in early stage breast cancer – The SUCCESS trial

Background: MUC1 based tumor markers like CA27.29 (TM) in breast cancer are routinely used in metastatic disease as early marker for treatment efficacy. However, in early stage disease data is sparse. In this analysis, we looked at the impact of individual change in CA27.29 on prognosis instead of using a threshold.

Methods: The SUCCESS Trial compares FEC-docetaxel (Doc) vs. FEC-Doc-Gemcitabine (Doc-G) regime and two vs. five year treatment with Zoledronat in 3754 patients (pts) with primary breast cancer (N+ or high risk N0). We measured CA27.29 after surgery but before chemotherapy (CHT) as baseline and compared it to CA27.29 levels 2 years thereafter with the ST AIA-PACK Ca27.29 reagent using MUC-1 for AIA-600II (Tosoh Bioscience, Tessenderlo, Belgium).

Results: CA27.29 data is available of 2,015 pts. 119 pts (5.9%) had TM over the threshold of 32U/ml before CHT and 56 (2.8%) 2years thereafter. To examine the relative change of tumor marker, pts were divided into 3 groups:

increase: change &gt;=5 U/ml; stable: change &lt;±5U/ml; decrease: change &gt; = −5 U/ml.

123 (6.1%) pts had increasing (&gt;=5 U/ml), 1419 (70.4%) had stable, 473 (23.5%) had decreasing TM levels from before CHT to 2 years thereafter. The majority of pts with increasing TM (86 pts; 69.9%) had levels below the usual threshold of 32U/ml at all times. Patients with an increase &gt;=5 U/ml had an 81% increased risk for recurrence (HR = 1.810 [CI: 1.111–2.948]) and reduced overall survival (HR = 1.020 [CI: 1.004–1.037]). In the multivariate analysis taking into account tumor size, nodal status, grading, age, hormonal and HER2/neu receptor status increasing CA27.29 levels were an independent prognostic marker.

Conclusions: An increase of the tumor marker CA27.29 2 years after CHT compared to pre-chemotherapy baseline was associated with a worse prognosis. By using this approach, more patients at risk for recurrence were detected than with the standard threshold approach. Therefore, the use of relative change could help to identify more patients at risk for relapse who might benefit from an intensified follow up.

Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P2-10-25.

Abstract P4-13-11: Prognostic factors in young breast cancer patients over time – a 40 year longitudinal analysis

Background: In younger patients (pts) breast cancer (BC) is associated with a worse prognosis compared to older pts. Only few data are available presenting the development of prognostic factors regarding a period of several decades. This 40 year (y) longitudinal comparison of the main prognostic factors was performed to investigate differences in younger women with primary BC in contrast to older women over time.

Patients and Methods: In this retrospective analysis a consecutive pts cohort of 4010 pts was analyzed. Pts were documented and treated for primary invasive breast cancer between 1963 and 2003 at two University Hospitals in Germany. To be eligible, pts were required to have identified tumor characteristics, including TNM-status. Pts with carcinoma in situ or distant metastases were excluded. The cohort was divided in two age groups, ≤40y and &gt;40y. Furthermore to reveal trends and changes over the duration of 41 years the period of analysis was split into 3 time frames: 1963–1976, 1977–1989 and 1990–2003. We analyzed the main prognostic factors for BC including tumor size, grading, nodal status and HR-status in longitudinal comparison regarding the three time frames, respectively. During 1963–77 HR-status was determined in just 12.6% of pts. Thus, this time frame was excluded in the analysis of HR-status.

Results: In 41 yrs, 747 (18.6%) pts were treated between 1963–76, 1722 pts (42.9%) in 1977–89 and 1541 pts (38.4%) in 1990–2003. Overall 358 pts were ≤40y and 3652 pts were over the age of 40.

A significant reduction of tumor size (metric assessment) at primary diagnosis was observed for both age groups (pts≤40y: p = 0.012; pts&gt;40y: p &lt; 0.0001) with no difference between the time frames, respectively (1963–76: p = 0.289; 1977–89: p = 0.647; 1990–2003: p = 0.937).

The number of node-positive pts significantly decreased in pts &gt;40 y (p = 0.001) whereas no difference could be seen in pts aged ≤40 y (p = 0.991).

In both age groups the number of G2/3 tumors increased over the yrs (pts≤40y: p = 0.001; pts&gt;40y: p &lt; 0.0001). Between 1963–76 more G1-tumors were diagnosed in younger pts (p = 0.041) whereas in the two following periods significantly more G2/3 tumors (p = 0.001; p = 0.002) were observed in this group.

In young pts, 54.2% were HR-negative in 1977–89 and 47.6% in 1990–2003 (p = 0.323). In pts &gt;40y 38.4% and 21.7% were HR-negative, respectively (p &lt; 0.0001). Comparing the age groups, significantly more pts were HR-negative in the young patient group (p = 0.001 (1977–89) and p &lt; 0.0001 (1990–2003)).

Conclusions: Concerning the large period of 40yrs, technical improvement and increasing awareness for BC are reasons for decreasing tumor size at the time of primary diagnosis. However, the rate of node-positive pts in the young patient group remained stable. Furthermore, the high percentage of HR-negative pts and the increasing number of pts with unfavorable tumor grade demonstrate more aggressive tumor types in younger pts. These data confirm the need to improve screening tools to early identify young women with the risk to develop breast cancer, and for personalized treatment approaches in these patients.

Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P4-13-11.

[Total knee arthroplasty in post-traumatic osteoarthritis]

BACKGROUND

This study aims to analyse the outcome and the complications after total knee arthroplasty in post-traumatic osteoarthritis in comparison to TKA in patients with degenerative osteoarthritis.

PATIENTS AND METHODS

In a period of six years 43 patients with a post-traumatic osteoarthritis were treated with a total knee arthroplasty (group PT). 38 (88 %) patients (age median 55 years, 22 female, 16 male) were investigated clinically and radiologically after an average follow-up time of 2.7 years. The OKS (Oxford Knee Score, max. 48 points), the Knee Society Scores "function" (max. 100 points) and "knee" (max. 100 points) as well as the visual analogue scale (VAS, 0 to 10 points) were recorded preoperatively and at follow-up. For comparison we chose a matched-pair selection of patients with degenerative osteoarthritis and TKA (group DO, age median 63 years, 22 female, 16 male). For statistical analysis we used common parametric tests (Wilcoxon and U test) and a level of significance of 0.05.

RESULTS

In 19 patients (50 %) of the group PT the osteoarthritis was caused by a bone injury. Furthermore in 19 patients a meniscal and/or ligamentous injury led to osteoarthritis. Out of all patients of group PT, 10 patients showed a preoperative valgus malalignment higher than 10°. KSS knee and KSS function added up to 76.9 and 84.9 points. So they are significantly less than in the matched group (DO, knee: 86.1; function: 94.4). Similarly, the OKS is significantly less in group PT after follow-up (PT: 32.3; DO: 38.4, p ≤ 0.05) although the preoperative values are equal in both groups. The VAS value decreased significantly in both groups. Initial level of pain was significantly higher in the group DO compared to the group PT. Patients with osteoarthritis after trauma showed complications in 17 cases (^ = 44.7 %) that led to 28 revision operations (^ = 0.7 operations per knee). The group with valgus malalignment had a revision rate of 1.4 operations per knee. In the group DO 8 complications occurred (^ = 21,1 %) that led to 11 revision operations (^=0.3 per knee). The deviation from the "ideal" leg axis could be reduced from 3.8° varus to 1.7° varus in the group DO and from 1.3° valgus auf 1.2° valgus in the group PT. Patients with a preoperative valgus deviation > 10° were reduced from 13.6° (± 3.9°) valgus to 0.5° (± 9.2°) varus.

CONCLUSION

Patients after TKA because of post-traumatic osteoarthritis show worse results concerning function and condition compared to patients with degenerative osteoarthritis. Heterogeneous pathogenesis and high rates of revision operations underline the complexity of this group of patients. The treatment has to be adjusted to the patient's requirements as well to the pathoanatomy.

[Clinical and radiological mid-term results after autologous osteochondral transplantation under consideration of quality of life]

BACKGROUND

Treatment of full-thickness cartilage defects remains a challenge in musculoskeletal surgery. Autologous osteochondral transplantation represents a possible solution for the repair of affected areas. However, some problems like degenerative changes of the transplanted cylinders and the surrounding cartilage or lack of cylinder integration to the surrounding cartilage arise with this method. Thus mid-term results respecting the quality of life are useful for assessment of the method.

PATIENTS/MATERIAL AND METHODS

We investigated 22 patients with a mean follow-up of 88 ± 14.5 months after autologous osteochondral transplantation due to a full-thickness cartilage defect of the medial femoral condyle. Beside clinical scores we assessed at follow-up the quality of life using the SF-36 health survey and the EQ-5D. Furthermore, radiological changes were detected and MRI was performed in 21 patients. A control group of 19 patients, treated with microfracture, was matched in terms of BMI, gender and age. Exclusion criteria for this group were tibial kissing lesion, ligament instability, arthrosis and malalignment.

RESULTS

In a longitudinal comparison with results 13.5 months after operation, no difference in Lysholm score was found. In plain radiographs higher degrees of arthritic changes in the medial compartment compared to the unaffected knee were observed. MRI revealed a mean modified MOCART score of 41.2 ± 7.7 for the OAT group and of 39.4 ± 16.1 for the microfracture group, without being significant. For OAT patients all cylinders showed an osseous integration. However, cylinder oedema was found in 9 patients. Those patients had a higher intensity of pain on a visual analogue scale. Quality of life was better for OAT patients in the physical scale of SF-36, but not in the mental scale.

CONCLUSION

Autologous osteochondral transplantation has an unaltered significance in treating full-thickness cartilage defects and leads to satisfying mid-term results. The development of early arthritic changes might not be preventable by this method. Oedema of the transplanted cylinders is attended by higher pain intensity and might be an indirect sign of cartilage degeneration.

DTCs in breast cancer: clinical research and practice

Minimal residual disease (MRD), i.e., isolated tumor cells (ITC) in bone marrow, may be the source of potentially fatal overt distant metastases in solid tumors even years after primary treatment. MRD can be detected by immunohistochemical methods using antibodies directed against cytokeratins, cell-surface markers, or molecular PCR-based techniques. Among solid tumors, the clinical relevance of MRD has been most extensively studied in breast cancer patients. The highest level of evidence for the prognostic impact of MRD in primary breast cancer was reached by a pooled analysis comprising more than 4,000 patients, showing poor outcome in patients with MRD at primary therapy. Yet, clinical application of MRD detection is hampered by the lack of a standardized detection assay. Moreover, clinical trial results demonstrating the benefit of a therapeutic interference derived from bone marrow status are still missing. Recent results suggest that in addition to its prognostic impact, MRD can be used for therapy monitoring or as a potential therapeutic target after phenotyping of the tumor cells. Persisting MRD after primary treatment may lead to an indication for extended adjuvant therapy. In a pooled analysis bone marrow aspirates of 726 patients from academic breast cancer units in Oslo (n=356), Munich (n=228), and Tuebingen (n=142) were analyzed during recurrence-free follow-up at a mean interval of 31.7 months after primary diagnosis of breast cancer pT1-4, pN0-3 pM0. Persistent ITC was detected in 15.4% of the patients (n=112). The Kaplan-Meier estimate for mean distant relapse-free survival estimate was 163.6 months in patients with negative and 105.2 months in patients with positive BM status. Patients without evidence of persistent ITC had a significantly longer overall survival (165.6), than patients with positive bone marrow status (103.3 months, p < .0001). Given these inspiring results on ITC in the bone marrow, several trials currently analyze the prognostic relecance of circulating tumor cells (CTC) in peripheral blood in the adjuvant setting. Persisting MRD after primary treatment may lead to an indication for extended adjuvant therapy. However, until clinical consequences of MRD detection in solid tumors and particularly in breast cancer have been validated, the detection of isolated tumor cells in bone marrow should be performed mainly in clinical trials.

P1-07-24: Quantitative and Immunohistochemical Detection of Breast Cancer Cells in Blood Samples

Background Disseminated tumor cells (DTCs) in bone marrow and circulating tumor cells (CTCs) in blood are found in patients with epithelial carcinomas (breast cancer) and are often correlated with poor prognosis of the disease. In current models circulating tumor cells (CTCs) dissolved from the primary tumor are thought to be responsible for the occurrence of metastases. However, the detection of CTCs is still a technical challenge. In this study, two methods for tumor cell detection of patients’ samples are presented (Real-Time-PCR and immunohisto-chemical staining). Both are simple and known methods with a high sensitivity and a spread marker panel.

Materials and Methods For the implementation of both methods, different breast cancer cell lines have been used (Cama-1, MCF-7; ZR-75-1). For Real-Time-PCR, blood samples of a healthy donors were spiked with different cell counts (0, 10, 100, 1000, 10.000 and 100.000) per ml blood sample. Total RNA was isolated from the samples, reversely transcribed into cDNA and used for TaqMan Real-Time-PCR reaction with probes against CK8, 18 and 19, while 18S was used as reference. Relative Quantification Curves were drawn by Microsoft™ Excel®. For immunohistochemical staining, cytospins were prepared from spiked blood samples, fixed with acetone, air dried and stained with antibodies against Her2- and Thomsen-Friedenreich-Antigen (CD176). In a second staining step fluorescently labelled secondary antibodies were applied. Nuclei were counterstained with DAPI, TF-Antigen was stained by Cy2 and Her2-Antigen by Cy3. The staining was controlled and documented by an epifluorescence microscope.

Results The curve of Relative Quantification for MCF-7 and ZR-75-1 cells shows an increasing slope starting from 1000 cells. For the Cama-1 cell line this trend is already seen from 10–100 cells. In ZR-75-1 all three genes analysed reveal this trend, whereas in Cama-1 and MCF-7 cells a strong increase in Relative Quantification is especially seen for CK8 and 18. In the immunohistochemical staining, the cells were considered as tumour cells if they showed staining with the antibody-combinations used. Stained cells were counted and recovery rates were determined. For ZR-75-1, 17 of 30 cells which were spiked in the blood samples were recovered. For MCF-7, 18 cells were found in average, and for Cama-1 23 cells were located per slide. The recovery rates calculated from these numbers are 56,6% and 60,0% for ZR-75-1 and MCF-7, for Cama-1 the recovery rate reaches 76,6%.

Conclusion It seems that Cama-1 cells are a better model than MCF-7 and ZR-75-1 for Real-Time PCR quantification of mamma carcinoma tumor cells in blood samples. MCF-7 and ZR-75-1 cells tend to react more likely immunologically with blood cells of the donor (agglutination between blood cells and cancer cells). The Cama-1 cell line shows also advantages in the detection of tumor cells using immunohistochemical staining. Therefore it will be necessary to test both methods on patient samples to proof their benefit.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P1-07-24.

P4-02-07: Influence of the Progesterone Receptor on the Prognosis of Breast Cancer in Interaction with Other Prognostic Factors

Introduction: The expression of the estrogen receptor (ER) and/or the progesterone receptor (PR) is a predictive factor for the response to endocrine treatment and to chemotherapy in primary breast cancer. Knowledge about the prognostic relevance of the PR is rare and partly controversial. Aim of this retrospective study was to analyze the prognostic relevance of PR.

Methods: Between 1995 and 2008, data from 5,144 patients with heterogeneously treated primary breast cancers have been collected in 3 German university hospitals.

The laboratories used immunhistochemical assays for the investigation of the ER and PR.

The PR-expression was correlated with patient and tumor characteristics.

For each outcome parameter overall survival (OS), distant disease free survival (DDFS) and local recurrence free survival (LRFS) cox proportional hazad models were built. Furthermore the effect of the PR status was analyzed according to tumor subgroups.

Results: PR status was associated with a more favourable OS, DDFS and LRFS in the univariate analysis. PR remained an independent prognostic factor for OS and DDFS but not for LRFS in the cox proportional hazard model.

For OS and DDFS the prognostic effect of PR seemed to be consistent among the subgroups and was significant for most of them. Comparing subgroups there was a difference between the HR for ER negatives and ER positives. In ER negative tumors the prognostic effect of the PR seemed to be larger (HR=0.40; 95%CI: 0.25−0.63) than in ER positives (HR=0.68; 95%CI: 0.53−0.87). For all other subgroups there seemed to be no interaction between PR status and the other prognostic factors.

Conclusion: PR positivity results into a similarly favourable prognosis in ER negative and ER positive patients. ER positivity alone seems not to be sufficient to define a group of patients with the most favourable prognosis. On the contrary, patients with ER positive, PR negative tumors have a signicantly deteriorated prognosis and seem to be a patient group, which should be investigated concerning drug resistance mechanisms.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P4-02-07.