Per Byström
Karolinska Institutet
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Featured researches published by Per Byström.
Journal of Clinical Oncology | 2008
Morten Brændengen; Kjell Magne Tveit; Åke Berglund; Elke Birkemeyer; Gunilla Frykholm; Lars Påhlman; Johan N. Wiig; Per Byström; Krzysztof Bujko; Bengt Glimelius
PURPOSE Preoperative chemoradiotherapy is considered standard treatment for locally advanced rectal cancer, although the scientific evidence for the chemotherapy addition is limited. This trial investigated whether chemotherapy as part of a multidisciplinary treatment approach would improve downstaging, survival, and relapse rate. PATIENTS AND METHODS The randomized study included 207 patients with locally nonresectable T4 primary rectal carcinoma or local recurrence from rectal carcinoma in the period 1996 to 2003. The patients received either chemotherapy (fluorouracil/leucovorin) administered concurrently with radiotherapy (50 Gy) and adjuvant for 16 weeks after surgery (CRT group, n = 98) or radiotherapy alone (50 Gy; RT group, n = 109). RESULTS The two groups were well balanced according to pretreatment characteristics. An R0 resection was performed in 82 patients (84%) in the CRT group and in 74 patients (68%) in the RT group (P = .009). Pathologic complete response was seen in 16% and 7%, respectively. After an R0 + R1 resection, local recurrence was found in 5% and 7%, and distant metastases in 26% and 39%, respectively. Local control (82% v 67% at 5 years; log-rank P = .03), time to treatment failure (63% v 44%; P = .003), cancer-specific survival (72% v 55%; P = .02), and overall survival (66% v 53%; P = .09) all favored the CRT group. Grade 3 or 4 toxicity, mainly GI, was seen in 28 (29%) of 98 and six (6%) of 109, respectively (P = .001). There was no difference in late toxicity. CONCLUSION CRT improved local control, time to treatment failure, and cancer-specific survival compared with RT alone in patients with nonresectable rectal cancer. The treatments were well tolerated.
Annals of Oncology | 2012
Chikako Suzuki; Lennart Blomqvist; Anders Sundin; Hans Jacobsson; Per Byström; Åke Berglund; Peter Nygren; Bengt Glimelius
BACKGROUND To determine whether the change in tumor diameters at the first follow-up computed tomography (CT) examination after baseline examination (first change) correlates with outcome in patients with metastatic colorectal cancer (mCRC) treated with combination chemotherapy. PATIENTS AND METHODS The first change was analyzed in a multicenter randomized phase III trial (Nordic VI, N = 567) comparing first-line irinotecan with either bolus or infused 5-fluorouracil. Cox proportional hazards multiple regression model and Kaplan-Meier survival analyses after correction for guarantee-time bias were carried out to evaluate correlations between first change, objective response according to RECIST 1.0, progression-free survival (PFS), and overall survival (OS). RESULTS The hazard ratios for PFS and OS decreased along with first change. A decrease between 10% and <30%, albeit RECIST does not regard this as a partial response, was a positive prognostic factor for PFS and OS. Patients who had new lesions or unequivocal progression of nonmeasurable lesions had a worse prognosis than those with only an increase in size of >20%. CONCLUSIONS The change in tumor size at the first follow-up CT is strongly prognostic for PFS and OS in mCRC.
Annals of Oncology | 2009
Per Byström; Åke Berglund; Ulrike Garske; Hans Jacobsson; Anders Sundin; Peter Nygren; J-E. Frödin; Bengt Glimelius
BACKGROUND To evaluate [(18)F]-2-fluoro-2-deoxy-D-glucose (FDG) positron emission tomography (PET), for early evaluation of response to palliative chemotherapy and for prediction of long-term outcome, in patients with metastatic colorectal cancer (mCRC). PATIENTS AND METHODS In a randomized trial, patients with mCRC received irinotecan-based combination chemotherapy. FDG-PET was carried out before treatment and after two cycles in 51 patients at two centers. Visual changes in tumor FDG uptake and changes measured semi-automatically, as standard uptake values (SUVs), were compared with radiological response after four and eight cycles. RESULTS The mean baseline SUV for all tumor lesions per patient was higher in nonresponders than in responders (mean 7.4 versus 5.6, P = 0.02). There was a strong correlation between metabolic response (changes in SUV) and objective response (r = 0.57, P = 0.00001), with a sensitivity of 77% and a specificity of 76%. There was no significant correlation between metabolic response and time to progression (P = 0.5) or overall survival (P = 0.1). CONCLUSIONS Although metabolic response assessed by FDG-PET reflects radiological tumor volume changes, the sensitivity and specificity are too low to support the routine use of PET in mCRC. Furthermore, PET failed to reflect long-term outcome and can, thus, not be used as surrogate end point for hard endpoint benefit.
Annals of Oncology | 2008
Bengt Glimelius; Halfdan Sorbye; Lise Balteskard; Per Byström; Per Pfeiffer; Kjell Magne Tveit; R Heikkilä; Nina Keldsen; Maria Albertsson; Hans Starkhammar; Hans Garmo; Åke Berglund
BACKGROUND To compare irinotecan with the Nordic 5-fluorouracil (5-FU) and folinic acid (FA) bolus schedule [irinotecan 180 mg/m(2) on day 1, 5-FU 500 mg/m(2) and FA 60 mg/m(2) on day 1 and 2 (FLIRI)] or the Lv5FU2 schedule [irinotecan 180 mg/m(2) on day 1, FA 200 mg/m(2), 5-FU bolus 400 mg/m(2) and infused 5-FU 600 mg/m(2) on day 1 and 2 (Lv5FU2-IRI)] due to uncertainties about how to administrate 5-FU with irinotecan. PATIENTS AND METHODS Patients (n = 567) with metastatic colorectal cancer were randomly assigned to receive FLIRI or Lv5FU2-IRI. Primary end point was progression-free survival (PFS). RESULTS Patient characteristics were well balanced. PFS did not differ between groups (median 9 months, P = 0.22). Overall survival (OS) was also similar (median 19 months, P = 0.9). Fewer objective responses were seen in the FLIRI group (35% versus 49%, P = 0.001) but the metastatic resection rate did not differ (4% versus 6%, P = 0.3). Grade 3/4 neutropenia (11% versus 5%, P = 0.01) and grade 2 alopecia (18% versus 9%, P = 0.002) were more common in the FLIRI group. The 60-day mortality was 2.4% versus 2.1%. CONCLUSIONS Irinotecan with the bolus Nordic schedule (FLIRI) is a convenient treatment with PFS and OS comparable to irinotecan with the Lv5FU2 schedule. Neutropenia and alopecia are more prevalent, but both regimens are equally well tolerated.
Acta Oncologica | 2008
Pehr Lind; Bengt Isaksson; Markus Almström; Anders Johnsson; Nils Albiin; Per Byström; Johan Permert
Background. The optimal care for patients with unresectable, non-metastatic pancreatic adenocarcinoma (PAC) is debated. We treated 17 consecutive cases with preoperative radiochemotherapy (RCT) as a means for downstaging their tumours and compared outcome with 35 patients undergoing direct surgery for primarily resectable PAC during the same time period. Methods. The patients had biopsy proven, unresectable, non-metastatic PAC which engaged ≥50% of the circumference of a patent mesenteric/portal vein for a distance ≥2 cm and/or <50% of the circumference of a central artery for <2 cm. The preop therapy included two courses of Xelox (oxaliplatin 130 mg/m2 d1; capecitabine 2 000 mg/m2 d1–14 q 3 w) followed by 3-D conformal radiotherapy (50.4 Gy; 1.8 Gy fractions) with reduced Xelox (d1-5 q 1 w X 6). Results. No incident of RCT-related CTC Grade 3–4 haematologic and six cases of non-haematologic side-effects were diagnosed. Sixteen patients completed the RCT and were rescanned with CT and reevaluated for surgery 4 weeks post-RCT. Five cases were diagnosed with new metastases to the liver. Eleven patients were accepted for surgery whereof eight underwent a curative R0-resection. The median overall survival for the latter group was 29 months, which compared favourably with our control group of patients undergoing direct curative surgery for primarily resectable PAC (median OS: 16 months; RO-rate: 75%). Perioperative morbidity was similar in the two cohorts but the duration of surgery was longer (576 vs. 477 min) and the op blood loss was greater (3288 vs. 1460 ml) in the RCT-cohort (p < 0.05). The 30-day mortality was zero in both groups. Conclusion. Preoperative RCT in patients with locally advanced PAC resulted in a high rate of curative resections and promising median survival in our treatment series. This trimodality approach merits further exploration in new studies, which are currently underway at our Department.
Acta Oncologica | 2012
Per Byström; Åke Berglund; Peter Nygren; Lisa Wernroth; Birgitta Johansson; Anders Larsson; Bengt Glimelius
Abstract Background. To evaluate the predictive and prognostic value of serum and plasma tumor markers, in comparison with clinical and biomedical parameters for response rate (RR), progression-free survival (PFS) and overall survival (OS) among patients with metastatic colorectal cancer (mCRC) treated with combination chemotherapy. Material and methods. One-hundred and six patients with mCRC from three centers, part of a multicenter study, received irinotecan with the Nordic bolus 5-fluorouracil (5-FU) and folinic acid schedule (FLIRI) or the de Gramont schedule (Lv5FU2-IRI). Blood samples for CEA, CA19-9, TPA, TIMP-1, SAA, transthyretin and CRP were taken at baseline and after two, four and eight weeks of treatment. Tumor marker levels at baseline and longitudinally were compared with responses evaluated (CT/MRI) after two and four months of treatment. The correlations to RR, PFS and OS were evaluated with regression analyses. Results. A significant correlation to OS was seen for baseline levels of all markers. In multivariate analyses with clinical parameters, TPA, CRP, SAA and TIMP-1 provided independent information. The baseline values of CEA, TPA and TIMP-1 were also significantly correlated to PFS and TPA to RR. Changes during treatment, i.e. the slope gave with the exception of CA19-9 for OS less information about outcomes. The best correlation to response was seen for CEA, CA19-9 and TPA with AUC values of 0.78, 0.83 and 0.79, respectively, using a combined model based upon an interaction between the slope and the baseline value. Conclusions. Baseline tumor markers together with clinical parameters provide prognostic information about survival in patients with mCRC. The ability of the individual tumor markers to predict treatment response and PFS is limited. Changes in marker levels during the first two months of treatment are less informative of outcome.
Annals of Oncology | 2010
Bengt Glimelius; M. Lahn; S. Gawande; A. Cleverly; C. Darstein; L. Musib; Y. Liu; K. L. Spindler; J-E. Frödin; Åke Berglund; Per Byström; Camilla Qvortrup; Anders Jakobsen; Per Pfeiffer
BACKGROUND Preclinically, protein kinase C and AKT activation can be inhibited by enzastaurin and reduce tumor growth of colorectal cancer cells. In asymptomatic patients with metastatic colorectal cancer (mCRC), enzastaurin activity was evaluated by measuring the 6-month progression-free survival (PFS) rate in a window study design. PATIENTS AND METHODS Chemonaive patients with asymptomatic mCRC who did not require immediate chemotherapy-induced tumor reduction received a 400-mg thrice daily loading dose of enzastaurin on day 1 of cycle 1, followed by 500 mg once daily for the remaining 28-day cycles. Progression was assessed on the basis of radiographic imaging, rise in carcinoembryonic antigen or lactate dehydrogenase (LDH) levels or by appearance of clinical symptoms. RESULTS Twenty-eight patients received daily enzastaurin. The 6-month PFS rate was 28% [95% confidence interval (CI) 13%-45%] and median PFS was 1.9 months (95% CI 1.8-4.5 months). Twelve (43%) patients had stable disease with a median duration of 6.1 months. The survival rate at 20 months was 77% (95% CI 47%-92%). No grade 4 toxicity was reported and grade 3 toxic effects were observed in three patients with one patient showing probable drug-related elevation of liver transaminases. CONCLUSION The window design in asymptomatic patients with mCRC can be safely applied to assess the activity and safety of novel cytostatic agents like enzastaurin.
Oncology | 2010
Bahir Aldulaymi; Per Byström; Åke Berglund; Ib Jarle Christensen; Nils Brünner; Hans Jørgen Nielsen; Bengt Glimelius
Objective: To evaluate whether combination chemotherapy leads to early changes in plasma TIMP-1 and serum carcinoembryonic antigen (CEA) levels in patients with metastatic colorectal cancer (mCRC), and whether such changes relate to subsequent objective response, time to progression (TTP) and overall survival. Materials and Methods: Eighty-eight patients with mCRC were included. Blood samples were collected before initiation and after 2, 4 and 6 weeks of treatment with an irinotecan-5-fluorouracil combination. Plasma TIMP-1 and serum CEA levels were determined by validated ELISA platforms. The first response evaluation was performed after 8 weeks of chemotherapy. Results: Median plasma TIMP-1 and serum CEA levels did not change significantly during 6 weeks of treatment. High plasma TIMP-1 and high serum CEA levels before treatment and at weeks 2, 4 and 6 were related to poor objective response. Moreover, high levels of plasma TIMP-1 before treatment and at weeks 2 and 4 were significantly associated with short TTP, while high levels of serum CEA at week 4 were significantly associated with short TTP. Finally, high levels of plasma TIMP-1 before and during treatment were significantly associated with poor overall survival; p < 0.0001 in all 4 determinations. A similar association between serum CEA and overall survival could only be demonstrated before treatment. Conclusion: Median plasma TIMP-1 or serum CEA levels do not change significantly during the first 6 weeks of chemotherapy for mCRC. The results indicate that plasma TIMP-1 in particular and serum CEA may be valuable biomarkers even in samples collected during treatment with chemotherapy.
Annals of Oncology | 2010
Bengt Glimelius; K. L. Spindler; J-E. Frödin; Åke Berglund; Per Byström; Camilla Qvortrup; Anders Jakobsen; Per Pfeiffer
Long-term follow-up of chemonaive patients with asymptomatic metastatic colorectal cancer treated with enzastaurin in a window of opportunity phase II study
Journal of Clinical Oncology | 2011
C. Suzuki; Lennart Blomqvist; Anders Sundin; Per Byström; Åke Berglund; Hans Jacobsson; Peter Nygren; Bengt Glimelius
3569 Background: Changes in tumor size using WHO RECIST-criteria have been extensively employed to monitor palliative chemotherapy and describe objective treatment response (OR). Few have questioned the fixed thresholds for response evaluation, particularly using RECIST and the relevance of an OR for patient prognosis is unclear. The aim was to determine whether the magnitude of change in tumor size at the first follow-up CT-examination after baseline examination (first change) correlates with outcome in patients with metastatic colorectal cancer (mCRC) treated with combination chemotherapy. METHODS The first change was retrospectively analyzed in a multicenter randomized phase III trial (Nordic VI, n=567) comparing first-line irinotecan with either bolus or infused 5-FU. Cox proportional hazards multiple regression model and Kaplan-Meier survival analyses after correction for guarantee-time bias were performed to evaluate correlations between first change, OR according to RECIST 1.0, progression-free survival (PFS) and overall survival (OS). RESULTS The first change strongly correlated with best OR (p<0.0001). The hazard ratio (HR) for PFS and OS decreased continuously along with first change. A decrease of 50% or more indicated a very favorable prognosis relative to an increase<10% [HR = 0.25 (95%CL 0.13-0.49) for OS and 0.35 (95%CL 0.21-0.59) for PFS]. Patients with the appearance of new lesions or unequivocal progression of non-measurable lesions had a worse prognosis than those with only an increase in size of more than 20%. CONCLUSIONS The change in tumor size at the first follow-up CT is a potent imaging surrogate of chemotherapy-induced tumor response and is strongly prognostic for PFS and OS in mCRC. The comparison of cytotoxic treatments in a trial can thus potentially be achieved more rapidly by the first change approach than to wait for maximal response evaluation using RECIST.