Proton beam therapy for invasive bladder cancer: A prospective study of bladder-preserving therapy with combined radiotherapy and intra-arterial chemotherapy

Proton beam therapy for muscle-invasive bladder cancer: A systematic review and analysis with Proton-Net, a multicenter prospective patient registry database

To assess the safety and efficacy of proton beam therapy (PBT) for muscle-invasive bladder cancer (MIBC), we examined the outcomes of 36 patients with MIBC (cT2-4aN0M0) who were enrolled in the Proton-Net prospective registry study and received PBT with concurrent chemotherapy from May 2016 to June 2018. PBT was also compared with X-ray chemoradiotherapy in a systematic review (X-ray (photon) radiotherapy). The radiotherapy consisted of 40-41.4 Gy (relative biological effectiveness (RBE) delivered in 20-23 fractions to the pelvic cavity or the entire bladder using X-rays or proton beams, followed by a boost of 19.8-36.3 Gy (RBE) delivered in 10-14 fractions to all tumor sites in the bladder. Concurrently, radiotherapy was given with intra-arterial or systemic chemotherapy of cisplatin alone or in combination with methotrexate or gemcitabine. Overall survival (OS), progression-free survival (PFS) and local control (LC) rates were 90.8, 71.4 and 84.6%, respectively, after 3 years. Only one case (2.8%) experienced a treatment-related late adverse event of Grade 3 urinary tract obstruction, and no severe gastrointestinal adverse events occurred. According to the findings of the systematic review, the 3-year outcomes of XRT were 57-84.8% in OS, 39-78% in PFS and 51-68% in LC. The weighted mean frequency of adverse events of Grade 3 or higher in the gastrointestinal and genitourinary systems was 6.2 and 2.2%, respectively. More data from long-term follow-up will provide us with the appropriate use of PBT and validate its efficacy for MIBC.

Efficacy of Intra-Arterial Plus Intravesical Chemotherapy for High-Risk Non-Muscle-Invasive Bladder Cancer: A Pooled Analysis

Background: The treatment for high-risk non-muscle-invasive bladder cancer (NMIBC) remains highly debated for its high recurrence and progression risk. This work aimed to verify the efficacy and toxicity of intra-arterial chemotherapy (IAC) plus intravesical chemotherapy (IVC) in high-risk NMIBC.

Methods: A comprehensive online literature search was conducted in three databases to select researches related to IAC + IVC for high-risk NMIBC. All data were analyzed using the Review Manager software version 5.3. And we used the Cochrane Risk of Bias tool to assessed the quality of these enrolled researches.

Results: Seven eligible original publications were enrolled in our studies with a total of 1,247 patients. Compared with the intravesical instillation, IAC + IVC therapy showed a better therapeutic effect. The total odds ratio for tumor recurrence rate, tumor progression rate, survival rate, and tumor-specific death rate was calculated as 0.51 (95% CI: 0.36–0.72; p < 0.05), 0.51 (95% CI: 0.36–0.72; p < 0.05), 1.75 (95% CI: 1.09–2.81; p < 0.05), and 0.48 (95% CI: 0.28–0.84; p < 0.05), respectively. In patients who received IAC, most of the adverse events (AEs)in the treatment were Grade I and II.

Conclusion: IAC + IVC regimen for high-risk NMIBC could effectively reduce recurrence and progression and provide a better prognosis than intravesical instillation. The adverse events of IAC were mild and acceptable.

Incidence and outcome of salvage cystectomy after bladder sparing therapy for muscle invasive bladder cancer: a systematic review and meta-analysis

Objective

We conducted a systematic review and meta-analysis to assess the available literature regarding the surgical and oncologic outcomes of patients undergoing salvage radical cystectomy (SV-RC) for recurrence or failure of bladder sparing therapy (BST) for muscle-invasive bladder cancer (MIBC).

Methods

We searched MEDLINE (PubMed), EMBASE and Google Scholar databases in May 2020. We included all studies of patients with ≥ cT2N0/xM0 bladder cancer that were eligible for all treatment modalities at the time of treatment decision who underwent BST including radiotherapy (RTX). A meta-analysis was conducted to calculate the pooled rate of several variables associated with an increased need for SV-RC. Study quality and risk of bias were assessed using MINORS criteria.

Results

73 studies comprising 9110 patients were eligible for the meta-analysis. Weighted mean follow-up time was 61.1 months (range 12–144). The pooled rate of non-response to BST and local recurrence after BST, the two primary reasons for SV-RC, was 15.5% and 28.7%, respectively. The pooled rate of SV-RC was 19.2% for studies with a follow-up longer than 5 years. Only three studies provided a thorough report of complication rates after SV-RC. The overall complication rate ranged between 67 and 72% with a 30-day mortality rate of 0–8.8%. The pooled rates of 5 and 10-year disease-free survival after SV-RC were 54.3% and 45.6%, respectively.

Conclusion

Approximately one-fifth of patients treated with BST with a curative intent eventually require SV-RC. This procedure carries a proportionally high rate of complications and is usually accompanied by an incontinent urinary diversion.

Electronic supplementary material

The online version of this article (10.1007/s00345-020-03436-0) contains supplementary material, which is available to authorized users.

Fitting the Generalized Target Model to Cell Survival Data of Proton Radiation Reveals Dose-Dependent RBE and Inspires an Alternative Method to Estimate RBE in High-Dose Regions

The imprecise estimation of the relative biological effectiveness (RBE) of proton radiation has been one of the main challenges for further calculating the biologically effective dose in proton therapy. Since dose levels can greatly influence the proton RBE, the relationship between the two should be clarified first. In addition, since the dose-response curves are usually too complex to readily assess RBE in high-dose regions, a reliable and simple method is needed to predict the RBE of proton radiation accurately in clinically relevant doses. The standard linear-quadratic (LQ) model is widely used to determine the RBE of particles for clinical applications. However, there has been some debate over its use when modeling the cell survival curves in high-dose regions, since those survival curves usually show linear behavior in the semilogarithmic plot. By considering both cellular repair effects and indirect effects of radiation, we have proposed a generalized target model with linear-quadratic linear (LQL) characteristics. For the more accurate evaluation of proton RBE in radiotherapy, here we used this generalized target model to fit the cell survival data in V79 and C3H 10T1/2 cells exposed to proton radiation with different LETs. The fitting results show that the generalized target model works as well as the LQ model in general. Based on the fitting parameters of the generalized target model, the RBE of six given doses D_T (RBE_T) could be calculated in the corresponding cell lines with different LETs. The results show that the RBE_T gradually decreases with increased dose in both cell types. In addition, inspired by the calculation method of the maximum values of RBE (RBE_M) in the low-dose region, a novel method was proposed for estimating the RBE in the high-dose region (RBE_H) based on the slope ratio of the dose-response curves in this region. Linear regression analysis indicated a significant linear correlation between the proposed RBE_H and the RBE_T in high-dose regions, which suggests that the current method can be used as an alternative tool, which is both simple and robust, to estimate RBE in high-dose regions.

Proton beam therapy for renal pelvis and ureter cancer: A report of 5 cases and a literature review

Standard treatment for localized renal pelvis and ureter cancer is surgery. Previously, the primary role of radiation therapy (RT) in cancer treatment was to control pain and hemostasis as palliative or as adjuvant therapy following surgery. In this report, we describe 5 patients with the disease treated with proton beam therapy (PBT) as curative treatment. Between September 2009 and July 2013, 5 males with renal pelvis (n=3) or ureter (n=2) cancer were treated by PBT with hypofractionated [72.6 Gy relative biological effectiveness (RBE)/22 fractions] or conventional [64-66 Gy (RBE)/32-33 fractions] fractionation. The median patient age was 72 years (range, 59-85 years). Three patients were deemed unfit for surgery. Local hypofractionated PBT was performed in 2 patients with T1-2N0M0 diseases, while prophylactic lymph node irradiation using a patch irradiation technique was performed for the remaining 3 patients, who had T3-4 disease. Two patients with T3-4 disease received chemotherapy prior to definitive PBT. No serious acute or late toxicities were observed in any patient. Local tumor control was achieved in 3 patients (60%); however, distant metastases were observed in 2 patients. Four of the five patients (80%) evaluated in the present study survived for >3 years. The data is limited; however, PBT appears to be a potential option for patients with renal pelvis or ureter cancer, especially for those who are unsuitable for radical surgery.

Long-term single-institute experience with trimodal bladder-preserving therapy with proton beam therapy for muscle-invasive bladder cancer

OBJECTIVE

We retrospectively elucidated the oncological outcomes, prognostic factors and toxicities of proton beam therapy in trimodal bladder-preserving therapy for muscle-invasive bladder cancer at our institution.

METHODS

From 1990 to 2015, 70 patients with cT2-3N0M0 muscle-invasive bladder cancer underwent trimodal bladder-preserving therapy consisting of maximal transurethral resection of the bladder tumor, small pelvis photon irradiation, intra-arterial chemotherapy and proton beam therapy. The overall survival rate, progression-free survival rate, time to progression, predictive factors for progression and toxicities were analyzed. Progression was defined as when muscle-invasive recurrence, distant metastasis or upper urinary tract recurrence was observed.

RESULTS

The patients' median age was 65 (range 36-85) years. The median follow-up period was 3.4 (range 0.6-19.5) years. The 5-year cumulative overall survival rate, progression-free survival rate and time to progression rate were 82%, 77%, and 82%, respectively. In univariate and multivariate analyses, tumor multiplicity and tumor size (≥5 cm) were significant and independent factors associated with progression (hazard ratio 3.5, 95% confidence interval 1.1-12; hazard ratio 5.0, 95% confidence interval 1.3-17; P < 0.05 for all). As for toxicity, 26 (18%) patients had grade 3-4 acute hematologic toxicities and 2 (3%) patients had grade 3 late genitourinary toxicity. No patient had to discontinue the treatment due to acute toxicity.

CONCLUSIONS

Our bladder-preserving therapy with proton beam therapy was well tolerated and achieved a favorable mortality rate. Tumor multiplicity and tumor size were important risk factors for progression. Our findings indicate that this therapy can be an effective treatment option for selected muscle-invasive bladder cancer patients.

Hyperthermia and radiotherapy in bladder cancer

Hyperthermia represents a unique, safe, and advantageous methodology for improving therapeutic strategies in the management of bladder cancer. This modality has shown promise in contributing to treatment regimens for both superficial and muscle-invasive disease. Especially in conjunction with intravesical chemotherapy, systemic therapy, and radiotherapy, hyperthermia shows particular synergistic benefit. As such, it should be explored further through clinical use and clinical trial in conjunction with currently available techniques and emerging technologies. However, to conceptualise the way forward, it is particularly important to understand the current challenges to widespread use of non-invasive, bladder-sparing approaches and the current state of bladder cancer care. As such, in the following article, we have focused on not only the rationale for concurrent radiotherapy and hyperthermia, but also the clinical landscape in bladder cancer as a whole.

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.

Discordance between preoperative and postoperative bladder cancer location: implications for partial-bladder radiation

PURPOSE

There is strong interest in partial-bladder radiation whether as a boost or definitive therapy to limit long-term toxicity. It is unclear that a standard preoperative examination can accurately identify all sites of disease within the bladder. The purpose of this study was to determine the correlation between preoperative localization of bladder tumors with postoperative findings to facilitate partial-bladder radiation techniques when appropriate.

METHODS AND MATERIALS

We examined patients with clinically staged T1-T4 invasive transitional cell carcinoma (TCC) or TCC with variant histology with no history of radiation or partial cystectomy undergoing radical cystectomy. Patients were scored as "under-detected" if a bladder site was involved with invasive disease (≥T1) at the time of cystectomy, but not identified preoperatively. Patients were additionally scored as "widely under-detected" if they had postoperative lesions that were not identified preoperatively in a given site, nor in any adjacent site. Rates of under-detected and widely under-detected lesions, as well as univariate and multivariate association between clinical variables and under-detection, were evaluated using logistic regression.

RESULTS

Among 222 patients, 96% (213/222) had at least 1 area of discordance. Fifty-eight percent of patients were under-detected in at least 1 location, whereas 12% were widely under-detected. Among 24 patients with a single site of disease on preoperative evaluation, 21/24 (88%) had at least 1 under-detected lesion and 14/24 (58%) were widely under-detected. On multivariate analysis, only solitary site of preoperative disease was associated with increased levels of under-detection of invasive disease (OR = 4.161, 95% CI, 1.368-12.657).

CONCLUSION

Our study shows a stark discordance between preoperative and postoperative localization of bladder tumors. From a clinical perspective, incomplete localization of all sites of disease within the bladder may lead to marginal misses when a partial-bladder technique is used.

Selective bladder preservation with curative intent for muscle-invasive bladder cancer: a contemporary review

Radical cystectomy plus urinary diversion, the reference standard treatment for muscle-invasive bladder cancer, associates with high complication rates and compromises quality of life as a result of long-term effects on urinary, gastrointestinal and sexual function, and changes in body image. As a society ages, the number of elderly patients unfit for radical cystectomy as a result of comorbidity will increase, and thus the demand for bladder-sparing approaches for muscle-invasive bladder cancer will also inevitably increase. Trimodality bladder-sparing approaches consisting of transurethral resection, chemotherapy and radiotherapy (Σ 55-65 Gy) yield overall survival rates comparable with those of radical cystectomy series (50-70% at 5 years), while preserving the native bladder in 40-60% of muscle-invasive bladder cancer patients, contributing to an improvement in quality of life for such patients. Limitations of the trimodality therapy include (i) muscle-invasive bladder cancer recurrence in the preserved bladder, which most often arises in the original muscle-invasive bladder cancer site; (ii) potential lack of curative intervention for regional lymph nodes; and (iii) increased morbidity in the event of salvage radical cystectomy for remaining or recurrent disease as a result of high-dose pelvic irradiation. Consolidative partial cystectomy with pelvic lymph node dissection followed by induction chemoradiotherapy at lower dose (e.g. 40 Gy) is a rational strategy for overcoming such limitations by strengthening locoregional control and reducing radiation dosage. Molecular profiling of the tumor and functional imaging might play important roles in optimal patient selection for bladder preservation. Refinement of radiation techniques, intensified concurrent or adjuvant chemotherapy, and novel sensitizers, including molecular targeting agent, are also expected to improve outcomes and consequently provide more muscle-invasive bladder cancer patients with favorable quality of life.

Role of radiation therapy for the treatment of lymph nodes in urologic malignancies

Radiation therapy (RT) represents an important therapeutic component in the management of genitourinary (GU) malignancies. RT is used to treat patients with proven involvement of the regional lymph nodes or delivered electively to patients at risk for occult regional lymph node metastases. Advances in treatment planning and delivery of various types of RT provide the technology to precisely plan, target, and deliver RT with the goal of optimizing the radiation dose to the target while sparing normal tissue. This article provides an overview of the modalities, indications, and techniques of RT for treatment of the lymphatic basins in GU malignancies.

Outcome following radical cystectomy and bladder-preservation therapy in patients with invasive carcinoma of urinary bladder

Background:

Invasive bladder cancer is a lethal disease with a 50% cancer-related mortality even in the best healthcare systems. Optimum combination of surgery, external beam radiotherapy and platinum-based chemotherapy has yet to be determined.

Purpose:

To audit the outcome of multi-modality treatment and compare this with the existing literature in order to set future priorities and re-audit in patients with invasive carcinoma of urinary bladder.

Materials and Methods:

Between January 2001 and December 2004, 97 patients with invasive carcinoma of urinary bladder were analyzed. Radical surgery was done in 18(18%) patients and adjuvant radiation was given to 20(21%) patients. Radical radiation alone, (≥50 Gy) was given to 26(27%) and chemoradiation to 33(34%) patients respectively. Patients in the chemoradiation arm were given the same dose of radiation with weekly concomitant cisplatin at 40 mg/ m² one hour before radiation during the first phase only. At a median follow-up of 32 months the outcome studied included locoregional failure, distant failure, disease-free survival (DFS) and overall survival (OS) using univariate and multivariate analyses. The OS and DFS were calculated according to Kaplan-Meier. Log rank test was used for statistical significance.

Results:

Median age of the patients was 58 years. Males comprised 93% of the total patients. Most (93%) of the patients had transitional cell histology. In patients treated with radiation alone overall response rate was 60%, with a complete response (CR) rate of 42%. The CR in patients treated with chemoradiation was 51%. Bladder was preserved in 61% of patients who received chemoradiation as compared to 42% in patients treated with radical radiation. With radical radiation local recurrence rate was 19% as compared to 22% with surgery and 6% with chemoradiation, respectively. Local recurrence rate was only 5% in patients treated with adjuvant radiation. Distant metastasis rate was least with chemoradiation (9%) as compared to 11.5% in radical radiation: curable dose of radiation and 33% with surgery alone, respectively. Patients with adjuvant radiation had a distant metastases rate of 15%. Median OS was 36 months. Factors affecting OS were histology (P = 0.023) and nodal involvement (P = 0.034). Median DFS was 26 months. Significant factors affecting DFS on univariate analysis were histology (P = 0.046) and nodal involvement (P = 0.004). On multivariate analysis the only factor affecting DFS and OS was nodal involvement (P = 0.01; Hazard Ratio, 0.085-0.719).

Conclusion:

In patients with invasive bladder cancer, combined modality in the form of radical cystectomy followed by radiation give best local control. Radiation alone is not effective to control muscle-invasive local disease; however, Chemoradiation is an effective alternative to radical cystectomy to preserve bladder function.

Conservative treatment of invasive bladder cancer

The concept of organ-preserving therapies is a trend in modern oncology, and several tumour types are now treated in this fashion. Trimodality therapy consisting of as thorough a transurethral resection of the bladder tumour as is judged safe, followed by concomitant chemoradiation therapy, is emerging as an attractive alternative for bladder preservation in selected patients with muscle-invasive bladder cancer. Long-term data from multiple institutional and cooperative group studies have shown that this approach is safe and effective and that it provides patients with the opportunity to maintain an intact and functional bladder with a survival rate similar to that for modern radical cystectomy.

[Is proton beam therapy the future of radiotherapy? Part I: clinical aspects]

Proton beam therapy uses positively charged particles, protons, whose physical properties improve dose-distribution (Bragg peak characterized by a sharp distal and lateral penumbra) compared with conventional photon-based radiation therapy (X-ray). These ballistic advantages apply to the treatment of deep-sited tumours located close to critical structures and requiring high-dose levels. [60-250 MeV] proton-beam therapy is now widely accepted as the "gold standard" in specific indications in adults--ocular melanoma, chordoma and chondrosarcoma of the base of skull --and is regarded as a highly promising treatment modality in the treatment of paediatric malignancies (brain tumours, sarcomas…). This includes the relative sparing of surrounding normal organs from low and mid-doses that can cause deleterious side-effects such as radiation-induced secondary malignancies. Other clinical studies are currently testing proton beam in dose-escalation evaluations, in prostate, lung, hepatocellular cancers, etc. Clinical validation of these new indications appears necessary. To date, over 60,000 patients worldwide have received part or all of their radiation therapy program by proton beams, in approximately 30 treatment facilities.

Radiochemotherapy for bladder cancer

Standard treatment for muscle-invasive bladder cancer is cystectomy. Multimodality treatment, including transurethral resection of the bladder tumour, radiation therapy, chemotherapy and deep regional hyperthermia, has been shown to produce survival rates comparable with those of cystectomy. With these programmes, cystectomy has been reserved for patients with incomplete response or local relapse. During the past two decades, organ preservation by multimodality treatment has been investigated in prospective series from single centres and co-operative groups, with more than 1000 patients included. Five-year overall survival rates in the range of 50-60% have been reported, and about three-quarters of the surviving patients maintained their bladder. Clinical criteria helpful in determining patients for bladder preservation include such variables as small tumour size (<5 cm), early tumour stage, a visibly and microscopically complete transurethral resection, absence of ureteral obstruction, and no evidence of pelvic lymph node metastases. On multivariate analysis, the completeness of transurethral resection of a bladder tumour was found to be one of the strongest prognostic factors for overall survival. Patients at greater risk of new tumour development after initial complete response are those with multifocal disease and extensive associated carcinoma in situ at presentation. Close co-ordination among all disciplines is required to achieve optimal results. Future investigations will focus on optimising radiation techniques, including all possibilities of radiosensitisation (e.g. concurrent radiochemotherapy, deep regional hyperthermia), and incorporating more effective systemic chemotherapy, and the proper selection of patients based on predictive molecular makers.

The potential clinical advantages of charged particle radiotherapy using protons or light ions

The increasing use of charged particle radiotherapy (CPT) in many countries will require British oncologists to establish their personal viewpoints on this subject in order to advise their patients regarding the merits or otherwise of obtaining such treatment abroad. This paper covers the advantages and some disadvantages of CPT in many anatomical locations on the basis of the achievable dose distributions as a consequence of the Bragg peak effect. The advantages in terms of normal tissue effects should follow the reduction of tissue volumes exposed to low/moderate dose: significant reductions in acute tissue effects are expected and experienced. For late reacting tissues, the predicted benefits are in the reduction of chronic low-grade symptoms and so improving the quality of life. For tumour control, dose escalation beyond what is achievable with X-ray therapy is possible only for some tumour types. Also, some tumours not presently treated by X-rays can be treated by CPT instead of radical surgery. Many of the available publications about CPT are at 'proof of principle' stage, as the treatment technique continues to be optimised: this is a similar situation to mega-voltage radiotherapy around 50 years ago. Oncologists in the UK need to familiarise themselves with CPT dose distributions, continually educate themselves by following the results of clinical studies as these emerge with time and hopefully visit CPT centres for direct experience.

The value of bladder-conserving strategies in muscle-invasive bladder carcinoma compared with radical surgery

PURPOSE OF REVIEW

Patients with muscle-invasive bladder cancer will practically all develop progression, often associated with severe side effects including pain, dysuria or macrohematuria. Recent reports demonstrate multimodality bladder-sparing approaches as primary treatment for muscle-invasive bladder cancer.

RECENT FINDINGS

Bladder-conserving strategies include thorough transurethral resection of the bladder tumor, external beam radiation therapy and chemotherapy. It has been shown that survival rates are similar to those of radical cystectomy series; additionally, a substantial number of patients survive with an intact bladder. The high costs, close cooperation between clinical specialists and a highly compliant patient need to be taken into consideration, however.

SUMMARY

Nowadays, the good long-term results after radical cystectomy with the creation of an orthotopic neobladder make the substantial advantage of a bladder-preserving strategy questionable when the patient's quality of life is addressed. Multimodality bladder-conserving strategies are a therapeutic option for selected patients; however, radical cystectomy remains the gold standard of treatment.

A systematic literature review of the clinical and cost-effectiveness of hadron therapy in cancer

BACKGROUND

In view of the continued increase in the number of hadron (i.e. neutron, proton and light or heavy ion) therapy (HT) centres we performed a systematic literature review to identify reports of the efficacy of HT.

METHODS

Eleven databases were searched systematically. No limit was applied to language or study design. Established experts were contacted for unpublished data. Data on outcomes were extracted and summarised in tabular form.

RESULTS

Seven hundred and seventy three papers were identified. For proton and heavy ion therapy, the number of RCTs was too small to draw firm conclusions. Based on prospective and retrospective studies, proton irradiation emerges as the treatment of choice for some ocular and skull base tumours. For prostate cancer, the results were comparable with those from the best photon therapy series. Heavy ion therapy is still in an experimental phase.

CONCLUSION

Existing data do not suggest that the rapid expansion of HT as a major treatment modality would be appropriate. Further research into the clinical and cost-effectiveness of HT is needed. The formation of a European Hadron Therapy Register would offer a straightforward way of accelerating the rate at which we obtain high-quality evidence that could be used in assessing the role of HT in the management of cancer.

Hypofractionated high-dose proton beam therapy for stage I non-small-cell lung cancer: preliminary results of a phase I/II clinical study

PURPOSE

To present treatment outcomes of hypofractionated high-dose proton beam therapy for Stage I non-small-cell lung cancer (NSCLC).

METHODS AND MATERIALS

Twenty-one patients with Stage I NSCLC (11 with Stage IA and 10 with Stage IB) underwent hypofractionated high-dose proton beam therapy. At the time of irradiation, patient age ranged from 51 to 85 years (median, 74 years). Nine patients were medically inoperable because of comorbidities, and 12 patients refused surgical resection. Histology was squamous cell carcinoma in 6 patients, adenocarcinoma in 14, and large cell carcinoma in 1. Tumor size ranged from 10 to 42 mm (median, 25 mm) in maximum diameter. Three and 18 patients received proton beam irradiation with total doses of 50 Gy and 60 Gy in 10 fractions, respectively, to primary tumor sites.

RESULTS

Of 21 patients, 2 died of cancer and 2 died of pneumonia at a median follow-up period of 25 months. The 2-year overall and cause-specific survival rates were 74% and 86%, respectively. All but one of the irradiated tumors were controlled during the follow-up period. Five patients showed recurrences 6-29 months after treatment, including local progression and new lung lesions outside of the irradiated volume in 1 and 4 patients, respectively. The local progression-free and disease-free rates were 95% and 79% at 2 years, respectively. No therapy-related toxicity of Grade > or =3 was observed.

CONCLUSIONS

Hypofractionated high-dose proton beam therapy seems feasible and effective for Stage I NSCLC. Proton beams may contribute to enhanced efficacy and lower toxicity in the treatment of patients with Stage I NSCLC.

Trimodality Treatment and Selective Organ Preservation for Bladder Cancer

Standard treatment for muscle-invasive bladder cancer is cystectomy. Trimodality treatment, including transurethral resection of the bladder tumor (TURBT), radiation therapy and chemotherapy, has been shown to produce survival rates comparable to those of cystectomy. With these programs, cystectomy has been reserved for patients with incomplete response or local relapse. During the past 15 years, organ preservation by trimodality treatment has been investigated in prospective series from single centers and cooperative groups, with more than 1,000 patients included. Five-year overall survival rates in the range of 50% to 60% have been reported, and approximately three quarters of the surviving patients maintained their bladder. Clinical criteria helpful in determining ideal patients for bladder preservation include early tumor stage (including high-risk T1 disease), a visibly complete TURBT, and absence of ureteral obstruction. Close coordination among all disciplines is required to achieve optimal results. Future investigations will focus on (1) optimizing radiation techniques and incorporating more effective systemic chemotherapy, and (2) the proper selection of patients based on molecular makers.