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Featured researches published by Sabine Bieri.


Journal of Clinical Oncology | 2004

Concomitant Cisplatin Significantly Improves Locoregional Control in Advanced Head and Neck Cancers Treated With Hyperfractionated Radiotherapy

Pia Huguenin; Karl T. Beer; Abdelkarim Said Allal; Kaspar Rufibach; Corinne Friedli; Jacques Bernard Davis; Bernhard C. Pestalozzi; Stephan Schmid; Armin Thöni; Mahmut Ozsahin; Jacques Bernier; Michael Töpfer; Roger Kann; Urs Richard Meier; Peter Thum; Sabine Bieri; Markus Notter; Norbert Lombriser; Christoph Glanzmann

PURPOSE To determine whether the application of two courses of cisplatin simultaneously with hyperfractionated radiotherapy improves the outcome in locally advanced and/or node-positive nonmetastatic carcinomas of the head and neck, compared with hyperfractionated radiotherapy alone. PATIENTS AND METHODS From July 1994 to July 2000, 224 patients with squamous cell carcinomas of the head and neck (excluding nasopharynx and paranasal sinus) were randomly assigned to hyperfractionated radiotherapy (median dose, 74.4 Gy; 1.2 Gy twice daily) or the same radiotherapy combined with two cycles of concomitant cisplatin (20 mg/m2 on 5 days of weeks 1 and 5). The primary end point was time to any treatment failure; secondary end points were locoregional failure, metastatic relapse, overall survival, and late toxicity. RESULTS There was no difference in radiotherapy between both treatment arms (74.4 Gy in 44 days). The full cisplatin dose was applied in 93% and 71% of patients during the first and second treatment cycles, respectively. Acute toxicity was similar in both arms. Median time to any treatment failure was not significantly different between treatment arms (19 months for combined treatment and 16 months for radiotherapy only, respectively) and the failure-free rate at 2.5 years was 45% and 33%, respectively. Locoregional control and distant disease-free survival were significantly improved with cisplatin (log-rank test, P = .039 and .011, respectively). The difference in overall survival did not reach significance (log-rank test, P = .147). Late toxicity was comparable in both treatment groups. CONCLUSION The therapeutic index of hyperfractionated radiotherapy is improved by concomitant cisplatin.


Journal of Clinical Oncology | 1996

Renal toxicity after allogeneic bone marrow transplantation: the combined effects of total-body irradiation and graft-versus-host disease.

Raymond Miralbell; Sabine Bieri; B Mermillod; C Helg; G Sancho; B Pastoors; A Keller; J M Kurtz; B Chapuis

PURPOSE To evaluate retrospectively the cumulative risk probability and factors correlated with renal dysfunction after allogeneic bone marrow transplantation (BMT). PATIENTS AND METHODS From October 1984 to July 1994, 84 patients with malignant hematopoietic diseases received allogeneic BMT after conditioning with high-dose chemotherapy and total-body irradiation (TBI). Seventy-nine patients with normal renal function before conditioning are included in this study. Conditioning included high-dose cyclophosphamide without (n = 46) or with (n = 33) other agents (daunorubicin, busulfan, cytarabine, and thiotepa) followed by TBI. The TBI dose prescribed to the center of the abdomen was 10 Gy for 24 patients, 12 Gy for 32, and 13.5 Gy for 23. In vitro T-cell depletion was undertaken in 48 cases. The post-BMT nephrotoxicity of aminoglycosides, vancomycin, amphotericin, and cyclosporine was assessed. Time to renal dysfunction was defined as the time to a persistent increase of serum creatinine (SCr) level greater than 110 mumol/L. The potential influence of sex, age, diagnosis, chimerism, and graft-versus-host disease (GvHD) on renal dysfunction was also assessed. RESULTS The 18-month probability of renal dysfunction-free survival (RDFS) for the whole group was 77%. Only TBI dose and presence of GvHD were significantly correlated with renal dysfunction by multivariate analysis. The 18-month probabilities of RDFS were 95%, 74%, and 55% for the patients conditioned with 10, 12, and 13.5 Gy, respectively. The 18-month RDFS probabilities were 88% and 61% for patients without and with GvHD, respectively. Combining both variables, we have defined two risk categories: low-risk (ie, 10 Gy TBI with/without GvHD and 12 Gy TBI without GvHD) and high-risk (ie, 12 Gy TBI with GvHD and 13.5 Gy TBI with/without GvHD). The predicted 18-month RDFS rates were 93% and 52% for the low- and high-risk groups, respectively. CONCLUSION Renal dysfunction after allogeneic BMT is strongly related to the delivered TBI dose (and dose per fraction) and to the presence of GvHD. Renal shielding should be recommended if a TBI dose greater than 12 Gy (fractionated twice daily over 3 days) is to be prescribed. Furthermore, in those cases with a high risk of developing GvHD (eg, unrelated allogeneic BMT, absence of T-cell depletion), these data suggest that kidney doses greater than 10 Gy should be avoided.


British Journal of Cancer | 2000

Sphincter-sparing surgery after preoperative radiotherapy for low rectal cancers: feasibility, oncologic results and quality of life outcomes

Abdelkarim Said Allal; Sabine Bieri; A Pelloni; V Spataro; S Anchisi; Patrick Ambrosetti; M A G Sprangers; John M. Kurtz; Philippe Gertsch

The present study assesses the choice of surgical procedure, oncologic results and quality of life (QOL) outcomes in a retrospective cohort of 53 patients with low-lying rectal cancers (within 6 cm of the anal verge) treated surgically following preoperative radiotherapy (RT, median dose 45 Gy) with or without concomitant 5-fluorouracil. QOL was assessed in 23 patients by using two questionnaires developed by the QOL Study Group of the European Organization for Research and Treatment of Cancer: EORTC QLQ-C30 and EORTC QLQ-CR38. After a median interval of 29 days from completion of RT, abdominoperineal resection (APR) was performed in 29 patients (55%), low anterior resection in 23 patients (20 with coloanal anastomosis) and transrectal excision in one patient. The 3-year actuarial overall survival and locoregional control rates were 71.4% and 77.5% respectively, with no differences observed between patients operated by APR or restorative procedures. For all scales of EORTC QLQ-C30 and EORTC QLQ-CR38, no significant differences in median scores were observed between the two surgical groups. Although patients having had APR tended to report a lower body image score (P = 0.12) and more sexual dysfunction in male patients, all APR patients tended to report better physical function, future perspective and global QOL. In conclusion, sphincter-sparing surgery after preoperative RT seems to be feasible, in routine practice, in a significant proportion of low rectal cancers without compromising the oncologic results. However, prospective studies are mandatory to confirm this finding and to clarify the putative QOL advantages of sphincter-conserving approaches.


International Journal of Radiation Oncology Biology Physics | 1997

Pediatric medulloblastoma: Radiation treatment technique and patterns of failure

Raymond Miralbell; Arnold Bleher; Pia Huguenin; Gerhard Ries; Roger Kann; RenéO. Mirimanoff; Markus Notter; Philippe Nouet; Sabine Bieri; Peter Thum; Hechmat Toussi

PURPOSE In this study factors are analyzed that may potentially influence the site of failure in pediatric medulloblastoma. Patient-related, disease-related, and treatment-related variables are analyzed with a special focus on radiotherapy time-dose and technical factors. METHODS AND MATERIALS Eighty-six children and adolescents with a diagnosis of medulloblastoma were treated in Switzerland during the period 1972-1991. Postoperative megavoltage radiotherapy was delivered to all patients. Simulation and portal films of the whole-brain irradiation (WBI) fields were retrospectively reviewed in 77 patients. The distance from the field margin to the cribiform plate and to the floor of the temporal fossa was carefully assessed and correlated with supratentorial failure-free survival. In 19 children the spine was treated with high-energy electron beams, the remainder with megavoltage photons. Simulation and port films of the posterior fossa fields were also reviewed in 72 patients. The field size and the field limits were evaluated and correlated with posterior fossa failure-free survival. RESULTS In 36 patients (47%) the WBI margins were judged to miss the inferior portion of the frontal and temporal lobes. Twelve patients failed in the supratentorial region and 9 of these patients belonged to the group of 36 children in whom the inferior portion of the brain had been underdosed. On multivariate analysis only field correctness was retained as being significantly correlated with supratentorial failure-free survival (p = 0.049). Neither the total dose to the spinal theca nor the treatment technique (electron vs. photon beams) were significantly correlated with outcome. Posterior fossa failure-free survival was not influenced by total dose, overall treatment time, field size, or field margin correctness. Overall survival was not influenced by any of the radiotherapy-related technical factors. CONCLUSION A correlation between WBI field correctness and supratentorial failure-free survival was observed. Treatment protocols should be considered that limit supratentorial irradiation mainly to subsites at highest risk of relapse. Optimized conformal therapy or proton beam therapy may help to reach this goal. Treating the spine with electron beams was not deletereous. A significant correlation between local control and other technical factors was not observed, including those relating to posterior fossa treatment. The use of small conformal tumor bed boost fields may be prefered to the larger posterior fossa fields usually considered as the standard treatment approach.


Journal of Clinical Oncology | 1999

Prospective Pilot Study of Sildenafil for Treatment of Postradiotherapy Erectile Dysfunction in Patients With Prostate Cancer

Damien C. Weber; Sabine Bieri; John M. Kurtz; Raymond Miralbell

PURPOSE Erectile dysfunction is a common late complication patients may experience after external-beam radiotherapy for prostate cancer. The efficacy and safety of oral sildenafil to correct sexual dysfunction caused by external-beam radiotherapy was studied in patients participating in our prospective trial. PATIENTS AND METHODS Thirty-five assessable patients participated in this prospective pilot study. Using a 25-point scale based on the International Index of Sexual Function, erectile dysfunction was assessed weekly, during which time patients received sildenafil 100 mg orally once a week for 6 consecutive weeks. Response was defined as a score of 18 or more, corresponding to at least one successful attempt at sexual intercourse per week. RESULTS Thirty patients (86%) completed the 6-week study. Seventy-seven percent of these patients had significantly improved erectile function, allowing recovery of full capacity for sexual intercourse. Of 27 patients not receiving concomitant hormone treatment, failure to respond was observed in only four patients (15%) compared with four (50%) of eight patients receiving hormonal treatment during the study. The time course of response was gradual, with 40%, 57%, 66%, 69%, and 74% responding at weeks 1 through 5, respectively. Therapy was generally well tolerated. The most frequently reported side effects in patients were flushing (37%), transient headache (17%), and dyspepsia (9%). No patient reported priapism, and no cardiovascular event or death was observed. After response, 12 patients (34%) reported the ability to achieve and maintain an erection sufficient for intercourse in the absence of sildenafil (ie, 24 hours to 6 days after taking the medication). CONCLUSION This study suggests that oral sildenafil is well tolerated and can reverse erectile dysfunction after radiotherapy in a substantial proportion of prostate cancer patients.


International Journal of Radiation Oncology Biology Physics | 1998

Altered apoptotic profiles in irradiated patients with increased toxicity

Nigel E. A. Crompton; Raymond Miralbell; Hans-Peter Rutz; Ersoy F; Ozden Sanal; Danielle Wellmann; Sabine Bieri; Philippe Coucke; Gillian C Emery; Yu-Quan Shi; Hans Blattmann; Mahmut Ozsahin

PURPOSE A retrospective study of radiation-induced apoptosis in CD4 and CD8 T-lymphocytes, from 12 cancer patients who displayed enhanced toxicity to radiation therapy and 9 ataxia telangiectasia patients, was performed to test for altered response compared to healthy blood-donors and normal cancer patients. METHODS AND MATERIALS Three milliliters of heparinized blood from each donor was sent via express post to the Paul Scherrer Institute (PSI) for subsequent examination. The blood was diluted 1:10 in RPMI medium, irradiated with 0-, 2-, or 9-Gy X-rays, and incubated for 48 h. CD4 and CD8 T-lymphocytes were then labeled using FITC-conjugated antibodies, erythrocytes were lysed, and the DNA stained with propidium iodide. Subsequently, cells were analyzed using a Becton Dickinson FACScan flow cytometer. Radiation-induced apoptosis was recognized in leukocytes as reduced DNA content attributed to apoptosis-associated changes in chromatin structure. Apoptosis was confirmed by light microscopy, electron microscopy, and by the use of commercially available apoptosis detection kits (in situ nick translation and Annexin V). Data from hypersensitive individuals were compared to a standard database of 105 healthy blood-donors, and a database of 48 cancer patient blood donors who displayed normal toxicity to radiation therapy. To integrate radiosensitivity results from CD4 and CD8 T-lymphocytes after 2 and 9 Gy, z-score analyses were performed. RESULTS A cohort of 12 hypersensitive patients was evaluated; 8 showed enhanced early toxicity, 3 showed enhanced late toxicity, and 1 showed both. The cohort displayed less radiation-induced apoptosis (-1.8 sigma) than average age-matched donors. A cohort of 9 ataxia telangiectasia homozygotes displayed even less apoptosis (-3.6 sigma). CONCLUSION The leukocyte apoptosis assay appears to be a useful predictor of individuals likely to display increased toxicity to radiation therapy; however, validation of this requires a prospective study.


International Journal of Radiation Oncology Biology Physics | 2000

Outcome and patterns of failure in testicular lymphoma: a multicenter rare cancer network study

Abderrahim Zouhair; Damien C. Weber; Yazid Belkacemi; Nicolas Ketterer; Pierre Yves Dietrich; Salvador Villà; Luciano Scandolaro; Sabine Bieri; Gabriela Studer; Françoise Delacretaz; Christophe Girardet; René O. Mirimanoff; Mahmut Ozsahin

PURPOSE To assess the outcome and patterns of failure in patients with testicular lymphoma treated by chemotherapy (CT) and/or radiation therapy (RT). METHODS AND MATERIALS Data from a series of 36 adult patients with Ann Arbor Stage I (n = 21), II (n = 9), III (n = 3), or IV (n = 3) primary testicular lymphoma, consecutively treated between 1980 and 1999, were collected in a retrospective multicenter study by the Rare Cancer Network. Median age was 64 years (range: 21-91 years). Full staging workup (chest X-ray, testicular ultrasound, abdominal ultrasound, and/or thoracoabdominal computer tomography, bone marrow assessment, full blood count, lactate dehydrogenase, and cerebrospinal fluid evaluation) was completed in 18 (50%) patients. All but one patient underwent orchidectomy, and spermatic cord infiltration was found in 9 patients. Most patients (n = 29) had CT, consisting in most cases of cyclophosphamide, doxorubicin, vincristine, and prednisolone (CHOP) with (n = 17) or without intrathecal CT. External RT was delivered to scrotum alone (n = 12) or testicular, iliac, and para-aortic regions (n = 8). The median RT dose was 31 Gy (range: 20-44 Gy) in a median of 17 fractions (10-24), using a median of 1.8 Gy (range: 1.5-2.5 Gy) per fraction. The median follow-up period was 42 months (range: 6-138 months). RESULTS After a median period of 11 months (range: 1-76 months), 14 patients presented lymphoma progression, mostly in the central nervous system (CNS) (n = 8). Among the 17 patients who received intrathecal CT, 4 had a CNS relapse (p = NS). No testicular, iliac, or para-aortic relapse was observed in patients receiving RT to these regions. The 5-year overall, lymphoma-specific, and disease-free survival was 47%, 66%, and 43%, respectively. In univariate analyses, statistically significant factors favorably influencing the outcome were early-stage and combined modality treatment. Neither RT technique nor total dose influenced the outcome. Multivariate analysis revealed that the most favorable independent factors predicting the outcome were younger age, early-stage disease, and combined modality treatment. CONCLUSIONS In this multicenter retrospective study, CNS was found to be the principal site of relapse, and no extra-CNS lymphoma progression was observed in the irradiated volumes. More effective CNS prophylaxis, including combined modalities, should be prospectively explored in this uncommon site of extranodal lymphoma.


International Journal of Radiation Oncology Biology Physics | 2001

Total body irradiation before allogeneic bone marrow transplantation: is more dose better?

Sabine Bieri; Claudine Helg; Bernard Chapuis; Raymond Miralbell

PURPOSE This study was performed to retrospectively assess the potential influence of total-body irradiation (TBI) dose on overall survival in patients undergoing allogeneic bone-marrow transplants (BMT) for hematologic malignancies. METHODS AND MATERIALS Between October 1984 and December 1996, 116 patients were conditioned with high-dose chemotherapy and fractionated TBI before allogeneic BMT. The median age was 34 years (range 3-60). The TBI dose was given in 6 fractions, twice-a-day, over 3 days before BMT. The total dose was 10 Gy in 24 patients, 12 Gy in 66 patients, and 13.5 Gy in 26 patients. RESULTS TBI dose was inversely correlated with overall survival. Five-year survival was 62% for patients conditioned with 10 Gy, 55% for patients conditioned with 12 Gy, and 46% for patients conditioned with 13.5 Gy. Age at BMT was also independently correlated with survival, with the best outcome for patients < 40 years old. CONCLUSION A TBI dose (fractionated) > 10 Gy may not necessarily be associated with a better outcome in patients undergoing allogeneic bone-marrow transplant for hematologic malignancies.


Radiotherapy and Oncology | 1999

Seminoma of the testis: is scrotal shielding necessary when radiotherapy is limited to the para-aortic nodes?

Sabine Bieri; Michel Rouzaud; Raymond Miralbell

PURPOSE To evaluate the influence of different shielding conditions and field geometry on the scatter dose to the remaining testicle during postoperative radiotherapy (RT) in seminoma. MATERIALS AND METHODS Testicular dose measurements were made with LiF thermoluminescent dosimeters (TLD) in 29 patients with stage I and IIA seminoma. The target volume consisted of para-aortic (PA) and para-aortic and homolateral iliac (PAI) lymph nodes in 14 and 15 patients, respectively. All patients had a scrotal shield as well as an additional block extending 7 cm inferiorly from the caudal field edge to shield the testicle from external scatter and collimator leakage. Doses with and without testicular blocks were measured for all patients. In seven patients treated exclusively to the PA region the gonadal dose was assessed according to four different shielding conditions: without any protection, with a gonadal shield alone, with the addition of an inferior field border block to the gonadal shield, and with the field border block alone. RESULTS For patients treated with PAI fields the mean testicular doses per fraction were 3.89 cGy (S.D. +/- 1.44) and 1.48 cGy (S.D. +/- 0.51) without and with gonadal shielding, respectively (P-value < 0.001); the corresponding values for PA fields were 1.86 cGy (S.D. +/- 0.86) and 0.65 cGy (S.D. +/- 0.35). For the patients treated to the PA region and assessed according to the four different shielding conditions, the additional external block to the testicular shield did not reduce significantly the measured dose on the testis. CONCLUSIONS These results suggest a benefit of gonadal shielding even in seminoma patients undergoing radiotherapy limited to the para-aortic region.


International Journal of Radiation Oncology Biology Physics | 2009

Hypofractionated Boost With High-Dose-Rate Brachytherapy and Open Magnetic Resonance Imaging–Guided Implants for Locally Aggressive Prostate Cancer: A Sequential Dose-Escalation Pilot Study

Carmen Ares; Youri Popowski; Sandro Pampallona; Philippe Nouet; G. Dipasquale; Sabine Bieri; Orhan Özsoy; Michel Rouzaud; Haleem Khan; Raymond Miralbell

PURPOSE To evaluate the feasibility, tolerance, and preliminary outcome of an open MRI-guided prostate partial-volume high-dose-rate brachytherapy (HDR-BT) schedule in a group of selected patients with nonmetastatic, locally aggressive prostatic tumors. METHODS AND MATERIALS After conventional fractionated three-dimensional conformal external radiotherapy to 64-64.4 Gy, 77 patients with nonmetastatic, locally aggressive (e.g., perineural invasion and/or Gleason score 8-10) prostate cancer were treated from June 2000 to August 2004, with HDR-BT using temporary open MRI-guided (192)Ir implants, to escalate the dose in the boost region. Nineteen, 21, and 37 patients were sequentially treated with 2 fractions of 6 Gy, 7 Gy, and 8 Gy each, respectively. Neoadjuvant androgen deprivation was given to 62 patients for 6-24 months. Acute and late toxicity were scored according to the Radiation Therapy Oncology Group/European Organization for Research and Treatment of Cancer scoring system. RESULTS All 77 patients completed treatment as planned. Only 2 patients presented with Grade > or =3 acute urinary toxicity. The 3-year probability of Grade > or =2 late urinary and low gastrointestinal toxicity-free survival was 91.4% +/- 3.4% and 94.4% +/- 2.7%, respectively. Rates of 3-year biochemical disease-free survival (bDFS) and disease-specific survival were 87.1% +/- 4.1% and 100%, respectively. CONCLUSIONS Boosting a partial volume of the prostate with hypofractionated HDR-BT for aggressive prostate cancer was feasible and showed limited long-term toxicity, which compared favorably with other dose-escalation methods in the literature. Preliminary bDFS was encouraging if one considers the negatively selected population of high-risk patients in this study.

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Jacques Bernier

Memorial Sloan Kettering Cancer Center

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