Value of PET imaging for radiation therapy

This comprehensive review written by experts in their field gives an overview on the current status of incorporating positron emission tomography (PET) into radiation treatment planning. Moreover, it highlights ongoing studies for treatment individualisation and per-treatment tumour response monitoring for various primary tumours. Novel tracers and image analysis methods are discussed. The authors believe this contribution to be of crucial value for experts in the field as well as for policy makers deciding on the reimbursement of this powerful imaging modality.

Value of PET imaging for radiation therapy

This comprehensive review written by experts in their field gives an overview on the current status of incorporating positron emission tomography (PET) into radiation treatment planning. Moreover, it highlights ongoing studies for treatment individualisation and per-treatment tumour response monitoring for various primary tumours. Novel tracers and image analysis methods are discussed. The authors believe this contribution to be of crucial value for experts in the field as well as for policy makers deciding on the reimbursement of this powerful imaging modality.

Adrenal Insufficiency in Patients with Corticosteroid-Refractory Cerebral Radiation Necrosis Treated with Bevacizumab

Cerebral radiation necrosis is a common complication of the radiotherapy of brain tumours that can cause significant mortality. Corticosteroids are the standard of care, but their efficacy is limited and the consequences of long-term steroid therapy are problematic, including the risk of adrenal insufficiency (AI). Off-label treatment with the vascular endothelial growth factor A antibody bevacizumab is highly effective in steroid-resistant radiation necrosis. Both the preservation of neural tissue integrity and the cessation of steroid therapy are key goals of bevacizumab treatment. However, the withdrawal of steroids may be impossible in patients who develop AI. In order to elucidate the frequency of AI in patients with cerebral radiation necrosis after treatment with corticosteroids and bevacizumab, we performed a retrospective study at our institution's brain tumour centre. We obtained data on the tumour histology, age, duration and maximum dose of dexamethasone, radiologic response to bevacizumab, serum cortisol, and the need for hydrocortisone substitution for AI. We identified 17 patients with cerebral radiation necrosis who had received treatment with bevacizumab and had at least one available cortisol analysis. Fifteen patients (88%) had a radiologic response to bevacizumab. Five of the 17 patients (29%) fulfilled criteria for AI and required hormone substitution. Age, duration of dexamethasone treatment, and time since radiation were not statistically associated with the development of AI. In summary, despite the highly effective treatment of cerebral radiation necrosis with bevacizumab, steroids could yet not be discontinued due to the development of AI in roughly one-third of patients. Vigilance to spot the clinical and laboratory signs of AI and appropriate testing and management are, therefore, mandated.

Re-irradiation of recurrent gliomas: pooled analysis and validation of an established prognostic score-report of the Radiation Oncology Group (ROG) of the German Cancer Consortium (DKTK)

The heterogeneity of high‐grade glioma recurrences remains an ongoing challenge for the interdisciplinary neurooncology team. Response to re‐irradiation (re‐RT) is heterogeneous, and survival data depend on prognostic factors such as tumor volume, primary histology, age, the possibility of reresection, or time between primary diagnosis and initial RT and re‐RT. In the present pooled analysis, we gathered data from radiooncology centers of the DKTK Consortium and used it to validate the established prognostic score by Combs et al. and its modification by Kessel et al. Data consisted of a large independent, multicenter cohort of 565 high‐grade glioma patients treated with re‐RT from 1997 to 2016 and a median dose of 36 Gy. Primary RT was between 1986 and 2015 with a median dose of 60 Gy. Median age was 54 years; median follow‐up was 7.1 months. Median OS after re‐RT was 7.5, 9.5, and 13.8 months for WHO IV, III, and I/II gliomas, respectively. All six prognostic factors were tested for their significance on OS. Aside from the time from primary RT to re‐RT (P = 0.074) and the reresection status (P = 0.101), all factors (primary histology, age, KPS, and tumor volume) were significant. Both the original and new score showed a highly significant influence on survival with P < 0.001. Both prognostic scores successfully predict survival after re‐RT and can easily be applied in the routine clinical workflow. Now, further prognostic features need to be found to even improve treatment decisions regarding neurooncological interventions for recurrent glioma patients.

Critical analysis of bladder sparing with trimodal therapy in muscle-invasive bladder cancer: a systematic review

CONTEXT

Aims of bladder preservation in muscle-invasive bladder cancer (MIBC) are to offer a quality-of-life advantage and avoid potential morbidity or mortality of radical cystectomy (RC) without compromising oncologic outcomes. Because of the lack of a completed randomised controlled trial, oncologic equivalence of bladder preservation modality treatments compared with RC remains unknown.

OBJECTIVE

This systematic review sought to assess the modern bladder-preservation treatment modalities, focusing on trimodal therapy (TMT) in MIBC.

EVIDENCE ACQUISITION

A systematic literature search in the PubMed and Cochrane databases was performed from 1980 to July 2013.

EVIDENCE SYNTHESIS

Optimal bladder-preservation treatment includes a safe transurethral resection of the bladder tumour as complete as possible followed by radiation therapy (RT) with concurrent radiosensitising chemotherapy. A standard radiation schedule includes external-beam RT to the bladder and limited pelvic lymph nodes to an initial dose of 40 Gy, with a boost to the whole bladder to 54 Gy and a further tumour boost to a total dose of 64-65 Gy. Radiosensitising chemotherapy with phase 3 trial evidence in support exists for cisplatin and mitomycin C plus 5-fluorouracil. A cystoscopic assessment with systematic rebiopsy should be performed at TMT completion or early after TMT induction. Thus, nonresponders are identified early to promptly offer salvage RC. The 5-yr cancer-specific survival and overall survival rates range from 50% to 82% and from 36% to 74%, respectively, with salvage cystectomy rates of 25-30%. There are no definitive data to support the benefit of using of neoadjuvant or adjuvant chemotherapy. Critical to good outcomes is proper patient selection. The best cancers eligible for bladder preservation are those with low-volume T2 disease without hydronephrosis or extensive carcinoma in situ.

CONCLUSIONS

A growing body of accumulated data suggests that bladder preservation with TMT leads to acceptable outcomes and therefore may be considered a reasonable treatment option in well-selected patients.

PATIENT SUMMARY

Treatment based on a combination of resection, chemotherapy, and radiotherapy as bladder-sparing strategies may be considered as a reasonable treatment option in properly selected patients.

Radiation therapy of optico-hypothalamic gliomas (OHG)--radiographic response, vision and late toxicity

BACKGROUND

Management strategies for optic pathway gliomas include observation, surgery, irradiation, chemotherapy and a combination of these modalities. It has been the policy of our University Hospital to consider radiation as the standard treatment for progressive optic pathway gliomas. This report describes the clinical presentation, treatment patterns and outcome with special emphasis on the long term functional status of patients with optico-hypothalamic gliomas (OHG).

PATIENTS AND METHODS

Between 1975 and 1997, 25 patients with OHG were treated by radiation therapy (RT) following surgery or biopsy. All patients received a local RT with a 0.5-1 cm margin around the lesions as depicted on CT or MRI scans. Age adjusted radiation doses ranged from 45 to 60 Gy with a single fraction size of 1.6-2 Gy. Endpoints of the study were: radiographic response, survival, progression-free survival and time to endocrinologic toxicity as well as the visual function during follow-up. The median follow-up time was 9 years (range, 1.5-23 years).

RESULTS

A partial response was noted in six (24%) of the patients, 13 (52%) patients had a stable tumour throughout the observation period and six (24%) patients had a tumour progression. Overall survival and progression-free survival rates were 94 and 69% at 10 years, respectively. A significant influence on progression-free survival was noted for age at diagnosis (P=0.04) and total dose (P=0.05). Nine out of 13 (69%) patients aged below 10 years compared with 3/12 (25%) patients aged above 10 years experienced hypothalamic-pituitary deficiency (P=0.008) during follow-up. As for visual acuity, nine patients had an improvement, another 13 patients a stable situation and three patients a measurable deterioration. Visual field deficits improved in three, remained unchanged in 16 patients and worsened in only one patient.

CONCLUSION

Postoperative RT with a total dose above 45 Gy should be considered as standard treatment in OHG with documented progression. Close radiographic monitoring and lifelong yearly evaluation for the need of possible hormone replacement are strongly recommended.

Simultaneous radiochemotherapy versus radiotherapy alone in advanced head and neck cancer: a randomized multicenter study

PURPOSE

A prospective randomized multicenter trial was performed to evaluate the contribution of simultaneously administered chemotherapy (CT) and radiotherapy (RT) in previously untreated patients with unresectable stage III/IV head and neck cancer.

PATIENTS AND METHODS

Patients with locoregionally advanced head and neck cancer were treated either with RT alone (arm A) or simultaneous RT plus CT (RCT; arm B). RT was identical in both arms and administered in three courses with 13 fractions of 1.8 Gy each twice daily. During one course, from day 3 to 11, 23.4 Gy was delivered. In arm B, cisplatin (CDDP) 60 mg/m2, fluorouracil (5-FU) 350 mg/m2 by intravenous (i.v.) bolus, and leucovorin (LV) 50 mg/m2 by i.v. bolus were given on day 2, and 5-FU 350 mg/m2/24 hour by continuous infusion and LV 100 mg/m2/24 hours by continuous infusion were given from day 2 to 5. Treatment was repeated on days 22 and 44; a total RT dose of 70.2 Gy was administered. Treatment breaks were scheduled from days 12 to 21 and days 34 to 43.

RESULTS

From 1989 to 1993, 298 patients were enrolled and 270 patients were assessable. Acute mucositis grade 3 or 4 was more frequent in arm B (38%) than in arm A (16%) (P < .001). Total treatment time was significantly longer in arm B than in arm A (P < .001) due to prolonged breaks. According to hematologic toxicity, scheduled drug doses were given in 74% of patients for the second course and 46% for the third course. The 3-year overall survival rate was 24% in arm A and 48% in arm B (P < .0003). The 3-year locoregional control rate was 17% in arm A and 36% in arm B (P < .004). Both arms showed similar distant failure patterns (arm A, 13 of 140; arm B, 12 of 130). Serious late side effects were not significantly different between treatment arms (arm A, 6.4%; arm B, 10%; not significant).

CONCLUSION

Concomitant CT offered improved disease control and survival in advanced head and neck cancer patients. Due to increased acute toxicity, more supportive care is demanded when CT is given simultaneously. Increased total treatment time does not exert a negative impact on outcome in this combined modality regimen.