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Concept: Radiation therapy

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Background The comparative effectiveness of treatments for prostate cancer that is detected by prostate-specific antigen (PSA) testing remains uncertain. Methods We compared active monitoring, radical prostatectomy, and external-beam radiotherapy for the treatment of clinically localized prostate cancer. Between 1999 and 2009, a total of 82,429 men 50 to 69 years of age received a PSA test; 2664 received a diagnosis of localized prostate cancer, and 1643 agreed to undergo randomization to active monitoring (545 men), surgery (553), or radiotherapy (545). The primary outcome was prostate-cancer mortality at a median of 10 years of follow-up. Secondary outcomes included the rates of disease progression, metastases, and all-cause deaths. Results There were 17 prostate-cancer-specific deaths overall: 8 in the active-monitoring group (1.5 deaths per 1000 person-years; 95% confidence interval [CI], 0.7 to 3.0), 5 in the surgery group (0.9 per 1000 person-years; 95% CI, 0.4 to 2.2), and 4 in the radiotherapy group (0.7 per 1000 person-years; 95% CI, 0.3 to 2.0); the difference among the groups was not significant (P=0.48 for the overall comparison). In addition, no significant difference was seen among the groups in the number of deaths from any cause (169 deaths overall; P=0.87 for the comparison among the three groups). Metastases developed in more men in the active-monitoring group (33 men; 6.3 events per 1000 person-years; 95% CI, 4.5 to 8.8) than in the surgery group (13 men; 2.4 per 1000 person-years; 95% CI, 1.4 to 4.2) or the radiotherapy group (16 men; 3.0 per 1000 person-years; 95% CI, 1.9 to 4.9) (P=0.004 for the overall comparison). Higher rates of disease progression were seen in the active-monitoring group (112 men; 22.9 events per 1000 person-years; 95% CI, 19.0 to 27.5) than in the surgery group (46 men; 8.9 events per 1000 person-years; 95% CI, 6.7 to 11.9) or the radiotherapy group (46 men; 9.0 events per 1000 person-years; 95% CI, 6.7 to 12.0) (P<0.001 for the overall comparison). Conclusions At a median of 10 years, prostate-cancer-specific mortality was low irrespective of the treatment assigned, with no significant difference among treatments. Surgery and radiotherapy were associated with lower incidences of disease progression and metastases than was active monitoring. (Funded by the National Institute for Health Research; Current Controlled Trials number, ISRCTN20141297 ; ClinicalTrials.gov number, NCT02044172 .).

Concepts: Cancer, Metastasis, Prostate cancer, Urology, Radiation therapy, Screening, Benign prostatic hyperplasia, Prostate-specific antigen

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The vast majority of all agents used to directly kill cancer cells (ionizing radiation, most chemotherapeutic agents and some targeted therapies) work through either directly or indirectly generating reactive oxygen species that block key steps in the cell cycle. As mesenchymal cancers evolve from their epithelial cell progenitors, they almost inevitably possess much-heightened amounts of antioxidants that effectively block otherwise highly effective oxidant therapies. Also key to better understanding is why and how the anti-diabetic drug metformin (the world’s most prescribed pharmaceutical product) preferentially kills oxidant-deficient mesenchymal p53(- -)cells. A much faster timetable should be adopted towards developing more new drugs effective against p53(- -) cancers.

Concepts: Cancer, Ionizing radiation, Metastasis, Oncology, Antioxidant, Chemotherapy, Radiation therapy, Leukemia

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Background Abiraterone acetate, an androgen biosynthesis inhibitor, improves overall survival in patients with metastatic castration-resistant prostate cancer after chemotherapy. We evaluated this agent in patients who had not received previous chemotherapy. Methods In this double-blind study, we randomly assigned 1088 patients to receive abiraterone acetate (1000 mg) plus prednisone (5 mg twice daily) or placebo plus prednisone. The coprimary end points were radiographic progression-free survival and overall survival. Results The study was unblinded after a planned interim analysis that was performed after 43% of the expected deaths had occurred. The median radiographic progression-free survival was 16.5 months with abiraterone-prednisone and 8.3 months with prednisone alone (hazard ratio for abiraterone-prednisone vs. prednisone alone, 0.53; 95% confidence interval [CI], 0.45 to 0.62; P<0.001). Over a median follow-up period of 22.2 months, overall survival was improved with abiraterone-prednisone (median not reached, vs. 27.2 months for prednisone alone; hazard ratio, 0.75; 95% CI, 0.61 to 0.93; P=0.01) but did not cross the efficacy boundary. Abiraterone-prednisone showed superiority over prednisone alone with respect to time to initiation of cytotoxic chemotherapy, opiate use for cancer-related pain, prostate-specific antigen progression, and decline in performance status. Grade 3 or 4 mineralocorticoid-related adverse events and abnormalities on liver-function testing were more common with abiraterone-prednisone. Conclusions Abiraterone improved radiographic progression-free survival, showed a trend toward improved overall survival, and significantly delayed clinical decline and initiation of chemotherapy in patients with metastatic castration-resistant prostate cancer. (Funded by Janssen Research and Development, formerly Cougar Biotechnology; ClinicalTrials.gov number, NCT00887198 .).

Concepts: Cancer, Metastasis, Oncology, Chemotherapy, Prostate cancer, Radiation therapy, Androgen, Prostate-specific antigen

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 To determine the association between vasectomy and prostate cancer, adjusting for measures of health seeking behaviour.

Concepts: Epidemiology, Clinical trial, Cancer, Metastasis, Obesity, Prostate cancer, Radiation therapy, Screening

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Discordant trends in the incidence of metastatic breast and prostate cancer since the widespread implementation of early-detection efforts may reflect distinct disease dynamics or may result from the different screening strategies used.

Concepts: Epidemiology, Cancer, Breast cancer, Metastasis, Prostate cancer, Radiation therapy, BRCA2, Screening

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Late rupture of external iliac artery pseudo-aneurysm is an uncommon complication in patients who undergo extensive gynecologic radical surgeries. A 28-year-old woman with stage IB cervical cancer underwent pelvic lymphadenectomy and extrafascial trachelectomy. Two months after surgery, massive bleeding from ruptured pseudo-aneurysm of the external iliac artery occurred. Endovascular management with covered stent placement was feasible and safe to stop bleeding.

Concepts: Cervical cancer, Surgery, Radiation therapy, Stent, Pelvis, Hysterectomy, External iliac artery, Internal iliac artery

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PURPOSE: New radiation therapy modalities have broadened treatment options for older women with breast cancer, but it is unclear how clinical factors, geographic region, and physician preference affect the choice of radiation therapy modality. METHODS AND MATERIALS: We used the Surveillance, Epidemiology, and End Results-Medicare database to identify women diagnosed with stage I-III breast cancer from 1998 to 2007 who underwent breast-conserving surgery. We assessed the temporal trends in, and costs of, the adoption of intensity modulated radiation therapy (IMRT) and brachytherapy. Using hierarchical logistic regression, we evaluated the relationship between the use of these new modalities and patient and regional characteristics. RESULTS: Of 35,060 patients, 69.9% received conventional external beam radiation therapy (EBRT). Although overall radiation therapy use remained constant, the use of IMRT increased from 0.0% to 12.6% from 1998 to 2007, and brachytherapy increased from 0.7% to 9.0%. The statistical variation in brachytherapy use attributable to the radiation oncologist and geographic region was 41.4% and 9.5%, respectively (for IMRT: 23.8% and 22.1%, respectively). Women undergoing treatment at a free-standing radiation facility were significantly more likely to receive IMRT than were women treated at a hospital-based facility (odds ratio for IMRT vs EBRT: 3.89 [95% confidence interval, 2.78-5.45]). No such association was seen for brachytherapy. The median radiation therapy cost per treated patient increased from $5389 in 2001 to $8539 in 2007. CONCLUSIONS: IMRT and brachytherapy use increased substantially from 1998 to 2007; overall, radiation therapy costs increased by more than 50%. Radiation oncologists played an important role in treatment choice for both types of radiation therapy, whereas geographic region played a bigger role in the use of IMRT than brachytherapy.

Concepts: Medicine, Cancer, Oncology, Chemotherapy, Radiation therapy, Radiation oncologist, Radiation oncology, External beam radiotherapy

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BACKGROUND: Pigmented villonodular synovitis (PVNS) is a rare locally aggressive tumors. PVNS is characterized in most cases by a specific t(1;2) translocation, which fuses the colony stimulating factor-1 (CSF1) gene to the collagen type VIa3 (COL6A3) promoter thus leading through a paracrine effect to the attraction of non-neoplastic inflammatory cells expressing CSF1-receptor. Imatinib is a tirosin-kinase inhibitors (TKI) active against CSF1-receptor whose activity in naive PVNS was already described. We report on two PVNS patients who responded to imatinib after failure to nilotinib, another CSF1-receptor inhibitor. METHODS: Since August 2012, 2 patients with progressive, locally advanced PVNS resistant to nilotinib (Patient1: man, 34 years; Patient2: woman, 24 years) have been treated with second-line imatinib 400 mg/day. Both patients are evaluable for response. RESULTS: Both pts are still on treatment (7 and 4 months). Patient1 had a dimensional response by MRI after 2 months from starting imatinib, together with symptomatic improvement. In Patient2 a metabolic response was detected by [18F]fluorodeoxyglucose–positron emission tomography (PET) at 6 weeks coupled with tumor shrinkage by MRI, and symptomatic improvement CONCLUSIONS: Imatinib showed antitumor activity in 2 patients with nilotinib-resistant PVNS. This observation strengthen the idea that targeted agent with similar profile can give a different clinical result, as already described for gastrointestinal stromal tumor (GIST) patients treated with the same agents. Molecular studies are needed to clarify the biologic mechanism(s) underlying the response.

Concepts: Cancer, Oncology, Brain tumor, Radiation therapy, Enzyme inhibitor, Chronic myelogenous leukemia, Gastrointestinal stromal tumor, Pigmented villonodular synovitis