Radiation therapy of breast cancer in the Nahe Breast Center: first results of an analysis in the context of health services research

BACKGROUND

The first evaluation of radiotherapy results in patients with breast cancer treated as part of a multimodal oncologic therapy in the Nahe Breast Center is presented. Analysis of the results was performed using an in-practice registry.

PATIENTS AND METHODS

From September 2016 to December 2017, 138 patients (median age 62.5 years; range 36-94 years) with breast cancer (right side, n = 67; left side, n = 71) received adjuvant radiation therapy. Of these, 103 patients received gyneco-oncologic care at the Nahe Breast Center, and 35 were referred from outside breast centers. The distribution into stages was as follows: stage I, n = 48; stage II, n = 68; stage III, n = 19; stage IV, n = 3. Neoadjuvant chemotherapy was given to 19 and adjuvant chemotherapy to 50 patients. Endocrine treatment was given to 120 patients. Both 3D conformal (n = 103) and intensity-modulated (n = 35) radiotherapy were performed with a modern linear accelerator.

RESULTS

With a median follow-up of 60 months (1-67), local recurrence occurred in 4/138 (2.9%) and distant metastasis in 8/138 (5.8%) patients; 7/138 (5.1%) patients died of their tumors during the follow-up period. The actuarial 5‑year local recurrence-free survival of all patients was 97.1%, and the actuarial 5‑year overall survival of all patients was 94.9%. We observed no grade 3 or 4 radiogenic side effects.

CONCLUSION

The results of radiotherapy for breast carcinoma at the Nahe Breast Center are comparable to published national and international results. In particular, the local recurrence rates in our study, determined absolutely and actuarially, are excellent, and demonstrate the usefulness of radiotherapy.

Flow cytometric CD34+ determination in stem cell transplantation: before or after cryopreservation of grafts?

Various attempts have been made to standardize and improve the reproducibility of flow cytometric determination of CD34+ hematopoietic progenitor cells. It is still not clear, however, whether the quantification of CD34+ cells in a stem cell graft should be done before or after cryopreservation. To address this issue, we investigated 78 unselected and 32 immunomagnetically selected autologous and allogeneic leukapheresis products (LA) before and after cryopreservation using pilot vials. Cell numbers were quantified within a Neubauer chamber, and CD34+ content was determined by flow cytometry; propidium iodide staining was used to exclude dead cells from analysis. Before freezing, the mean viable CD34 cell content in the unselected samples was 1.22% and increased after thawing to a mean of 2.16% of viable cells. Taking into account cell loss and cell death, the overall recovery of viable cells was 64.5%; all CD34+ cells could be recovered. Mean purity in the CD34-selected cell fraction was 85% (48-97) before and 91.3% (67-99) after thawing. The number of viable cells was 86.8% before and 86.1% after freezing with a 93.9% recovery of total cells. This leads to a mean 93.7% (SD +/- 23.1) recovery of viable cells and 100% (SD +/- 22.3) recovery of viable CD34+ cells. There was no significant difference in tolerance to freeze/thaw stress between cells from heavily pretreated autologous patients and healthy allogeneic donors. Our data show that freezing significantly increases the percentage of CD34(+) cells in unmanipulated LA, probably due to the death of granulocytes and mononuclear cells (MNCs). Nevertheless, the overall number of viable CD34+ cells in unselected as well as selected samples remains unchanged. Thus, CD34 data from different laboratories, for example, within multicenter trials, should be comparable independent of the different time points of acquisition.

Adhesion molecules on peripheral blood-derived CD34+ cells: effects of cryopreservation and short-term ex vivo incubation with serum and cytokines

The homing of hematopoietic precursor cells (HPC) within the bone marrow is most likely to be mediated by specific adhesion via surface receptors to cellular and extracellular matrix (ECM) components and to be regulated by cytokines. We investigated the effects of serum and cytokines on the expression of adhesion molecules on cryopreserved and fresh peripheral blood-derived progenitor cells (PBPC) and on the adhesion of PBPC to various ECM proteins. PBPC were collected from patients by leukapheresis during G-CSF-supported recovery from conventional cancer chemotherapy. Freezing markedly reduced the fraction of CD34+ cells with L-selectin (CD62L) expression from 62 to 11% and also diminished the fluorescence intensity for the integrin subunits CD29 and CD49d on CD34+ cells. A 14 h incubation of thawed PBPC with serum induced re-expression of adhesion molecules. The addition of the cytokine cocktails (G-CSF + SCF + IL-3 + IL-11 or IL-4 + IL-1beta + IFN-gamma) or MGDF, however, exerted no effects in addition to serum alone. Furthermore, when compared to serum alone, the addition of cytokine cocktails or MGDF did not alter the fraction of fresh PB-CD34+ cells adhering to collagen I, collagen IV, fibronectin, laminin or vitronectin. HPC adhesion to ECM components might be refractory to short-term alterations of the cytokine environment. Alternatively, longer incubation times or other cytokines may be necessary to modulate the expression of adhesion molecules on hematopoietic progenitor cells or adhesion itself under ex vivo conditions.

Chemopurging of peripheral blood-derived progenitor cells by alkyl-lysophospholipid and its effect on haematopoietic rescue after high-dose therapy

One reason for relapse after high-dose tumor therapy with subsequent autologous stem cell transplantation is tumor cell contamination of the graft. Removal of tumor cells from bone marrow grafts by chemopurging with the ether lipid edelfosine has been established as an effective and simple method. When compared with bone marrow derived grafts, progenitor cells from peripheral blood have considerably reduced the haematological recovery times. However, this advantage is put at risk by the nonspecific haematotoxic activity of the purging agent. We therefore compared the in vitro recovery of peripheral blood derived progenitor cells (PBPC) from either non-purged (n = 41) or purged (75 micrograms/ml of ether lipid for 4 h at 37 degrees C, n = 48) leukapheresis products. The recovery of CFU-GM after cryopreservation was 63 +/- 4% without and 48 +/- 3% with purging (P = 0.007). After high-dose therapy, patients (n = 37) received similar amounts of either non-purged (n = 17) or purged (n = 20) autologous PBPC. The median haematological recovery times (non-purged vs purged) to > 500 WBC/microlitres were 9.0 vs 8.5 days after transplantation, to > 2000 PMN/microlitres 10.5 vs 10.0 days, and to > 50,000 PLT/microlitres 15.5 vs 14.0 days. All differences were statistically not significant. We conclude that ether lipid purging of PBPC leads to a significant, however tolerable loss of progenitor cells in vitro, and that haematological recovery times after high-dose therapy are identically short, provided similar amounts of PBPC are reinfused.

Inhibition of proliferation and clonal growth of human breast cancer cells by interleukin 13

We tested the influence of recombinant human interleukin (rhIL)-l3 and rhIL-4 on clonal growth of human breast cancer cell lines. rhIL-13 and rhIL-4 inhibited clonal growth of three of nine lines to approximately 50% of controls (ED50, 0.5 ng/ml). rhIl-13 reduced [3H]thymidine incorporation in all three cell lines: two showing a minor (84% and 83% of controls) and one showing a major response (25% of control). Both cytokines markedly reduced serum-induced G(0/1) exit (approximately 25% versus 60%). 125I-labeled interleukin (IL) 13 binding assays revealed high-affinity binding sites for IL-13 on two of the three responding cell lines (KD approximately 60 pM). (Y124D)IL-4 effectively antagonized all effects of rhIl-13 and rhIL-4, arguing for shared receptor components between them. However, neither rhIl-4 nor (Y124D) IL-4 could displace 125I-labeled IL-13 from binding, although unlabeled rhIL-13 effectively did so. Using reverse transcription-PCR, we studied the expression of the common gamma chain (gammac) in responding cell lines, putatively being shared between IL-4 receptor and IL-13 receptor; none of the three cell lines express gammac. In conclusion, we demonstrate antiproliferative effects of IL-4 and IL-13 on carcinoma cells which express IL-13 binding sites without participation of gammac.

Immunomagnetic selection of CD34+ cells from fresh peripheral blood mononuclear cell preparations using two different separation techniques

Immunomagnetic separation using anti-CD34 monoclonal antibodies and paramagnetic microspheres has been used to enrich hematopoietic stem cells from human bone marrow, whole cord blood, or mobilized peripheral blood mononuclear cell collections. The aim of the present study was to compare the efficacy of two different CD34+ cell selection techniques in enriching CD34+ cells from mobilized fresh peripheral blood mononuclear cells. Using the magnetic cell sorter (MACS), the final product purity was 74.1% CD34+ cells (starting population 2.3% +/- 3.3%) with a 60.3% CD34+ cell yield. Using Dynabeads and subsequent chymopapain incubation for releasing the target cells from the beads (Isolex system), the released cells contained 83.3% CD34+ cells (starting population 1.2% +/- 0.7%) with a 43.4% yield. These results indicate that CD34+ cells can be isolated with high purity from fresh leukapheresis products using both immunomagnetic techniques.

Limitations of pulse oral calcitriol therapy in continuous ambulatory peritoneal dialysis patients

Calcitriol is increasingly used for therapy of secondary hyperparathyroidism in patients with end-stage renal disease. Its therapeutic efficacy, however, often has been limited by the associated increase in intestinal calcium and phosphorus absorption. Previous studies reported that these side effects could be avoided by intermittent administration of calcitriol in high doses, subsequently referred to as pulse therapy. The present study was designed to investigate pulse oral calcitriol therapy in a patient subgroup especially susceptible to the development of hypercalcemia and hyperphosphatemia under standard continuous calcitriol treatment. We examined 15 peritoneal dialysis patients with moderate degrees of hyperparathyroidism (intact parathyroid hormone [iPTH] levels, 150 to 903 pg/mL) ingesting between 1.5 and 6 g of calcium salts as the sole phosphate binders. Treatment consisted of 0.5 microgram calcitriol twice weekly. Eight of these patients had been previously converted to low calcium dialysate to tolerate the necessary doses of phosphate-binding calcium salts. During the study period, comprising 8 pretreatment weeks and 8 weeks of therapy, dialysates and doses of calcium salts were not changed, so that only calcitriol influenced the determined parameters. As expected, iPTH levels decreased rapidly in all patients (P < 0.0001). However, within 4 weeks of treatment a marked increase in calcium phosphorus products was observed (P < 0.0001). Overt hypercalcemia developed in five patients. We concluded that pulse oral calcitriol has to be carefully monitored in peritoneal dialysis patients receiving high doses of calcium salts because of the increased risk for hypercalcemia and hyperphosphatemia.

[Effect of observation time on the perception of details in x-ray pictures]

The authors studied the influence of perception time on the quantified image quality of radiographs, using as an experimental basis the target presentation time during which there was no active involvement of the observer. No change in the influence on the observer was seen down to an observation time of 1 sec.; there was a slight but practically negligible drop on further reduction to 0.5 sec. At 0.1 sec. there was a drop that would have been approximately compensated by a contrast enhancement of object detail to about twice the original value. The influence of the perception time was placed in relation to an example of the influence of structured noise on the detection performance. This influence proved to be significantly greater than that of time. A comparison of the concept of "conspicuity" as defined by Revesz and Kundel was set in relation to the term "Auffälligkeit" ("distinctiveness") coined by Stender. It was established that the quality reserve QR after Borcke corresponds to "Auffälligkeit" as defined by Stender and should best be separated from image quality changes dues to the influence of structured noise on the detection of radiological abnormalities.