Consolidative active scanning proton therapy for mediastinal lymphoma: selection criteria, treatment implementation and clinical feasibility

AIMS

Proton therapy (PT) represents an advanced form of radiotherapy with unique physical properties which could be of great advantage in reducing long-term radiation morbidity for cancer survivors. Here, we aim to describe the whole process leading to the clinical implementation of consolidative active scanning proton therapy treatment (PT) for mediastinal lymphoma.

METHODS

The process included administrative, technical and clinical issues. Authorization of PT is required in all cases as mediastinal lymphoma is currently not on the list of diseases reimbursable by the Italian National Health Service. Technically, active scanning PT treatment for mediastinal lymphoma is complex, due to the interaction between actively scanned protons and the usually irregular and large volumes to be irradiated, the nearby healthy tissues and the target motion caused by breathing. A road map to implement the technical procedures was prepared. The clinical selection of patients was of utmost importance and took into account both patient and tumor characteristics.

RESULTS

The first mediastinal lymphoma was treated at our PT center in 2018, four years after the start of the clinical activities. The treatment technique implementation included mechanical deep inspiration breath-hold simulation computed tomography (CT), clinical target volume (CTV)-based multifield optimization planning and plan robustness analysis. The ultimate authorization rate was 93%. In 4 cases a proton-photon plan comparison was required. Between May 2018 and February, 2021, 14 patients were treated with consolidative PT. The main clinical reasons for choosing PT over photons was a bulky disease in 8 patients (57%), patient's age in 11 patients (78%) and the proximity of the lymphoma to cardiac structures in 10 patients (71%). With a median follow-up of 15 months (range, 1-33 months) all patients but one (out-of-field relapse) are without evidence of disease, all are alive and no late toxicities were observed during the follow-up period.

CONCLUSIONS

The clinical implementation of consolidative active scanning PT for mediastinal lymphoma required specific technical procedures and a prolonged experience with PT treatments. An accurate selection of patients for which PT could be of advantage in comparison with photons is mandatory.

Is it beneficial to use apertures in proton radiosurgery with a scanning beam? A dosimetric comparison in neurinoma and meningioma patients

PURPOSE

To assess the dosimetric advantages of apertures in intracranial single fraction proton radiosurgery.

MATERIALS AND METHODS

Six neuroma and 10 meningioma patients were investigated. For each patient, six plans were computed, with two spot spacing and three aperture settings (no apertures, 5 and 8 mm margin between aperture and clinical target volume [CTV]). All plans were optimized on the CTV with the same beam arrangement and the same single-field robust optimization (2 mm setup errors, 3.5% range uncertainties). Robustness analysis was performed with 0.5 and 1.0 mm systematic setup errors and 3.5% range uncertainties. CTV coverage in the perturbed scenarios and healthy brain tissue sparing in the surrounding of the CTV were compared.

RESULTS

Meningiomas were larger and at a shallow depth than neuromas. In neuromas, spot spacing did not affect OAR doses or the robustness of CTV coverage and the apertures reduced brain dose without any significant impact on CTV robustness. In meningiomas, smaller spot spacing produced a reduction in brain V5Gy and improved robustness of CTV coverage; in addition, an 8 mm margin aperture reduced low and medium brain tissue doses without affecting robustness in the 0.5 mm perturbed scenario. A 5 mm margin aperture caused a reduction of plan robustness.

CONCLUSION

The optimal use of apertures is a trade-off between sparing of low and medium dose to the healthy brain and robustness of target coverage, also depending on size and depth of the lesion.

Multicomponent T2 relaxometry reveals early myelin white matter changes induced by proton radiation treatment

PURPOSE

To investigate MRI myelin water imaging (MWI) by multicomponent T₂ relaxometry as a quantitative imaging biomarker for brain radiation-induced changes and to compare it with DTI.

METHODS

Sixteen patients underwent fractionated proton therapy (PT) receiving dose to the healthy tissue because of direct or indirect (base skull tumors) irradiation. MWI was performed by a multi-echo sequence with 32 equally spaced echoes (10-320 ms). Decay data were processed to identify 3 T₂ compartments: myelin water (Mw) below 40 ms, intra-extracellular water (IEw) between 40 and 250 ms, and free water (CSFw) above 250 ms. Both MWI and DTI scans were acquired pre (pre)-treatment and immediately at the end (end) of PT. After image registration, voxel-wise difference maps, obtained by subtracting MWI and DTI pre from those acquired at the end of PT, were compared with the corresponding biological equivalent dose (BED).

RESULTS

Mw difference showed a positive correlation and IEw difference showed a negative correlation with BED considering end-pre changes (P < .01). The changes in CSFw were not significantly correlated with the delivered BED. The changes in DTI data, considering end-pre acquisitions, showed a positive correlation between fractional anisotropy and the delivered BED.

CONCLUSION

MWI might detect early white matter radiation-induced alterations, providing additional information to DTI, which might improve the understanding of the pathogenesis of the radiation damage.

Methodologies to Increase the Level of Evidence of Real-life Proton Therapy in Head and Neck Tumors

This review aims to present and assess available and new methodologies to increase the clinical evidence of proton therapy data for patients with head and neck cancer. Despite the increasing number of scientific reports showing the feasibility and effectiveness of proton therapy in head and neck cancer, clinical evidence on the potential benefits of its use remains low for several reasons. In this article, the pros and cons of consolidated and new methodologies in this setting such as randomized clinical trials, the model-based approach, and the use of prospective multicentric registries will be detailed.

Magnetic Resonance Imaging during Proton Therapy Irradiation Allows for the Early Response Assessment of Pediatric Chordoma

Chordoma in pediatric patients is very rare. Proton therapy has become a gold standard in the treatment of these neoplasms, as high dose escalation can be achieved regarding the target while maximizing the sparing of the healthy tissues near the tumor. The aim of the work was to assess the evolution of morphological sequences during treatment using T1/T2-weighted magnetic resonance imaging (MRI) for the early response assessment of a classic chordoma of the skull base in a pediatric patient who had undergone surgical excision. Our results demonstrated a significant quantitative reduction in the residual nodule component adhered to the medullary bulb junction, with an almost complete recovery of normal anatomy at the end of the irradiation treatment. This was mainly shown in the T2-weighted MRI. On the other hand, the classic component of the lesion was predominantly present and located around the tooth of the axis. The occipital condyles were morphologically and dimensionally stable for the entire irradiation period. In conclusion, the application of this type of monitoring methodology, which is unusual during the administration of a proton treatment for chordoma, highlighted the unexpected early response of the disease. At the same time, it allowed the continuous assessment of the reliability of the treatment plan.

Rosette-Forming Glioneuronal Tumor of the Fourth Ventricle: A Case of Relapse Treated with Proton Beam Therapy

Rosette-forming glioneuronal tumors (RGNTs) are rare, grade I, central nervous system (CNS) tumors typically localized to the fourth ventricle. We describe a 9-year-old girl with dizziness and occipital headache. A magnetic resonance imaging (MRI) revealed a large hypodense posterior fossa mass lesion in relation to the vermis, with cystic component. Surgical resection of the tumor was performed. A RGNT diagnosis was made at the histopathological examination. During follow-up, the patient experienced a first relapse, which was again surgically removed. Eight months after, MRI documented a second recurrence at the local level. She was a candidate for the proton beam therapy (PBT) program. Three years after the end of PBT, the patient had no evidence of disease recurrence. This report underlines that, although RGNTs are commonly associated with an indolent course, they may have the potential for aggressive behavior, suggesting the need for treatment in addition to surgery. Controversy exists in the literature regarding effective management of RGNTs. Chemotherapy and radiation are used as adjuvant therapy, but their efficacy management has not been adequately described in the literature. This is the first case report published in which PBT was proposed for adjuvant therapy in place of chemotherapy in RGNT relapse.

Proton therapy: A therapeutic opportunity for aggressive pediatric meningioma

Meningiomas are an extremely rare histology among pediatric brain tumors, and there is a shortage of literature on their management. Proton therapy is currently used safely and effectively for many types of both pediatric and adult cancer, and its main advantage is the sparing of healthy tissues from radiation, which could translate in the reduction of late side effects. We review the literature on radiotherapy and proton therapy for pediatric meningiomas and report clinical outcomes for two aggressive pediatric meningiomas we treated with protons. Proton therapy might be a safe and effective therapeutic option for this rare subgroup of tumors.

Quantitative Multicomponent T2 Relaxation Showed Greater Sensitivity Than Flair Imaging to Detect Subtle Alterations at the Periphery of Lower Grade Gliomas

Purpose

To demonstrate that quantitative multicomponent T2 relaxation can be more sensitive than conventional FLAIR imaging for detecting cerebral tissue abnormalities.

Methods

Six patients affected by lower-grade non-enhancing gliomas underwent T2 relaxation and FLAIR imaging before a radiation treatment by proton therapy (PT) and were examined at follow-up. The T2 decay signal obtained by a thirty-two-echo sequence was decomposed into three main components, attributing to each component a different T2 range: water trapped in the lipid bilayer membrane of myelin, intra/extracellular water and cerebrospinal fluid. The T2 quantitative map of the intra/extracellular water was compared with FLAIR images.

Results

Before PT, in five patients a mismatch was observed between the intra/extracellular water T2 map and FLAIR images, with peri-tumoral areas of high T2 that typically extended outside the area of abnormal FLAIR hyper-intensity. Such mismatch regions evolved into two different types of patterns. The first type, observed in three patients, was a reduced extension of the abnormal regions on T2 map with respect to FLAIR images (T2 decrease pattern). The second type, observed in two patients, was the appearance of new areas of abnormal hyper-intensity on FLAIR images matching the anomalous T2 map extension (FLAIR increase pattern), that was considered as asymptomatic radiation induced damage.

Conclusion

Our preliminarily results suggest that quantitative T2 mapping of the intra/extracellular water component was more sensitive than conventional FLAIR imaging to subtle cerebral tissue abnormalities, deserving to be further investigated in future clinical studies.

Clinical implementation of pencil beam scanning proton therapy for liver cancer with forced deep expiration breath hold

PURPOSE

To present our technique for liver cancer treatments with proton therapy in pencil beam scanning mode and to evaluate the impact of uncertainties on plan quality.

MATERIALS AND METHODS

Seventeen patients affected by liver cancer were included in this study. Patients were imaged and treated in forced breath-hold using the Active Breathing Coordinator system and monitored with an optical tracking system. Three simulation CTs were acquired to estimate the anatomical variability between breath-holds and generate an internal target volume (ITV). The treatment plans were optimized with a Single Field Optimization technique aimed at minimizing the use of range shifter. Plan robustness was tested simulating systematic range and setup uncertainties, as well as the interplay effect between breath-holds. The appropriateness of margin was further verified based on the actual positioning data acquired during treatment.

RESULTS

The dose distributions of the nominal plans achieved a satisfactory target coverage in 11 out of 17 patients, while in the remaining 6 D₉₅ to the PTV was affected by the constraint on mean liver dose. The constraints for all other organs at risk were always within tolerances. The interplay effect had a limited impact on the dose distributions: the worst case scenario showed a D₉₅ reduction in the ITV < 3.9 GyRBE and no OAR with D₁ > 105% of the prescription dose. The robustness analysis showed that for 13 out of 17 patients the ITV coverage in terms of D₉₅ was better than D₉₅ of the PTV in the nominal plan. For the remaining 4 patients, the maximum difference between ITV D₉₅ and PTV D₉₅ was ≤0.7% even for the largest simulated setup error and it was deemed clinically acceptable. Hot spots in the OARs were always lower than 105% of the prescription dose. Positioning images confirmed that the breath hold technique and the PTV margin were adequate to compensate for inter- and intra-breath-hold variations in liver position.

CONCLUSION

We designed and clinically applied a technique for the treatment of liver cancer with proton pencil beam scanning in forced deep expiration breath-hold. The initial data on plan robustness and patient positioning suggest that the choices in terms of planning technique and treatment margins are able to reach the desired balance between target coverage and organ at risk sparing.

Proton or photon radiosurgery for cardiac ablation of ventricular tachycardia? Breath and ECG gated robust optimization

PURPOSE

Ventricular tachycardia (VT) is a life-threatening heart disorder. The aim of this preliminary study is to assess the feasibility of stereotactic body radiation therapy (SBRT) photon and proton therapy (PT) plans for the treatment of VT, adopting robust optimization technique for both irradiation techniques.

METHODS

ECG gated CT images (in breath hold) were acquired for one patient. Conventional planning target volume (PTV) and robust optimized plans (25GyE in single fraction) were simulated for both photon (IMRT, 5 and 9 beams) and proton (SFO, 2 beams) plans. Robust optimized plans were obtained both for protons and photons considering in the optimization setup errors (5 mm in the three orthogonal directions), range (±3.5%) and the clinical target volume (CTV) motion due to heartbeat and breath-hold variability.

RESULTS

The photon robust optimization method, compared to PTV-based plans, showed a reduction in the average dose to the heart by about 25%; robust optimization allowed also reducing the mean dose to the left lung from 3.4. to 2.8 Gy for 9-beams configuration and from 4.1 to 2.9 Gy for 5-beams configuration. Robust optimization with protons, allowed further reducing the OAR doses: average dose to the heart and to the left lung decreased from 7.3 Gy to 5.2 GyE and from 2.9 Gy to 2.2 GyE, respectively.

CONCLUSIONS

Our study demonstrates the importance of the optimization technique adopted in the treatment planning system for VT treatment. It has been shown that robust optimization can significantly reduce the dose to healthy cardiac tissues and that PT further increases this gain.

Clinical results of active scanning proton therapy for primary liver tumors

BACKGROUND

Evidence for the efficacy of radiation therapy for primary liver cancer is growing. In this context, proton therapy (PT) can potentially improve the therapeutic ratio, as demonstrated by recent clinical studies. Here we report the first European clinical experience on the use of PT for primary liver cancer.

METHODS

All patients treated for primary liver cancer in our center entered the analysis. Patients were simulated during deep expiration breath-hold. A 15-fraction treatment schedule was adopted using active scanning PT. Clinical outcome and toxicity were retrospectively analyzed.

RESULTS

Between January 2018 and December 2019, 18 patients were treated. Fourteen patients had hepatocellular carcinoma (HCC), three patients had intrahepatic cholangiocarcinoma (ICC), and one patient had synchronous ICC-HCC. The Child-Pugh score was A5 in the majority of patients with HCC (71.4%). Median prescription dose was 58.05 Gy (range, 50.31-67.5). Median follow-up was 10 months (range, 1-19). The majority of deaths occurred from liver tumor progression. One-year overall survival (OS) was 63%. A significant correlation between worse OS and patient performance status, vascular invasion, and tumor stage was recorded. One-year local control was 90%. Toxicity was low, with a decrease in Child-Pugh score ⩾2 points detected in one patient. No cases of classic radiation-induced liver disease occurred.

CONCLUSIONS

Our initial results of active scanning PT for primary liver cancer demonstrated the feasibility, safety, and effectiveness of this advanced technique in this setting. The potential of the combination of PT with other locoregional therapies is under evaluation.

Clinical implementation in proton therapy of multi-field optimization by a hybrid method combining conventional PTV with robust optimization

To implement a robust multi-field optimization (MFO) technique compatible with the application of a Monte Carlo (MC) algorithm and to evaluate its robustness. Nine patients (three brain, five head-and-neck, one spine) underwent proton treatment generated by a novel robust MFO technique. A hybrid (hMFO) approach was implemented, planning dose coverage on isotropic PTV compensating for setup errors, whereas range calibration uncertainties are incorporated into PTV robust optimization process. hMFO was compared with single-field optimization (SFO) and full robust multi-field optimization (fMFO), both on the nominal plan and the worst-case scenarios assessed by robustness analysis. The SFO and the fMFO plans were normalized to hMFO on CTV to obtain iso-D95 coverage, and then the organs at risk (OARs) doses were compared. On the same OARs, in the normalized nominal plans the potential impact of variable relative biological effectiveness (RBE) was investigated. hMFO reduces the number of scenarios computed for robust optimization (from twenty-one in fMFO to three), making it practicable with the application of a MC algorithm. After normalizing on D95 CTV coverage, nominal hMFO plans were superior compared to SFO in terms of OARs sparing (p   <  0.01), without significant differences compared to fMFO. The improvement in OAR sparing with hMFO with respect to SFO was preserved in worst-case scenarios (p   <  0.01), confirming that hMFO is as robust as SFO to physical uncertainties, with no significant differences when compared to the worst case scenarios obtained by fMFO. The dose increase on OARs due to variable RBE was comparable to the increase due to physical uncertainties (i.e. 4-5 Gy(RBE)), but without significant differences between these techniques. hMFO allows improving plan quality with respect to SFO, with no significant differences with fMFO and without affecting robustness to setup, range and RBE uncertainties, making clinically feasible the application of MC-based robust optimization.

Modelling the risk of radiation induced alopecia in brain tumor patients treated with scanned proton beams

PURPOSE

To develop normal tissue complication probability (NTCP) models for radiation-induced alopecia (RIA) in brain tumor patients treated with proton therapy (PT).

METHODS AND MATERIALS

We analyzed 116 brain tumor adult patients undergoing scanning beam PT (median dose 54 GyRBE; range 36-72) for CTCAE v.4 grade 2 (G2) acute (≤90 days), late (>90 days) and permanent (>12 months) RIA. The relative dose-surface histogram (DSH) of the scalp was extracted and used for Lyman-Kutcher-Burman (LKB) modelling. Moreover, DSH metrics (Sx: the surface receiving ≥ X Gy, D_2%: near maximum dose, D_mean: mean dose) and non-dosimetric variables were included in a multivariable logistic regression NTCP model. Model performances were evaluated by the cross-validated area under the receiver operator curve (ROC-AUC).

RESULTS

Acute, late and permanent G2-RIA was observed in 52%, 35% and 19% of the patients, respectively. The LKB models showed a weak dose-surface effect (0.09 ≤ n ≤ 0.19) with relative steepness 0.29 ≤ m ≤ 0.56, and increasing tolerance dose values when moving from acute and late (22 and 24 GyRBE) to permanent RIA (44 GyRBE). Multivariable modelling selected S_21Gy for acute and S_25Gy, for late G2-RIA as the most predictive DSH factors. Younger age was selected as risk factor for acute G2-RIA while surgery as risk factor for late G2-RIA. D_2% was the only variable selected for permanent G2-RIA. Both LKB and logistic models exhibited high predictive performances (ROC-AUCs range 0.86-0.90).

CONCLUSION

We derived NTCP models to predict G2-RIA after PT, providing a comprehensive modelling framework for acute, late and permanent occurrences that, once externally validated, could be exploited for individualized scalp sparing treatment planning strategies in brain tumor patients.

Harmonization of proton treatment planning for head and neck cancer using pencil beam scanning: first report of the IPACS collaboration group

Background and purpose: A collaborative network between proton therapy (PT) centres in Trento in Italy, Poland, Austria, Czech Republic and Sweden (IPACS) was founded to implement trials and harmonize PT. This is the first report of IPACS with the aim to show the level of harmonization that can be achieved for proton therapy planning of head and neck (sino-nasal) cancer.Methods: CT-data sets of five patients were included. During several face-to-face and online meetings, a common treatment planning protocol was developed. Each centre used its own treatment planning system (TPS) and planning approach with some restrictions specified in the treatment planning protocol. In addition, volumetric modulated arc therapy (VMAT) photon plans were created.Results: For CTV1, the average D_median was 59.3 ± 2.4 Gy(RBE) for protons and 58.8 ± 2.0 Gy(RBE) for VMAT (aim was 56 Gy(RBE)). For CTV2, the average D_median was 71.2 ± 1.0 Gy(RBE) for protons and 70.6 ± 0.4 Gy(RBE) for VMAT (aim was 70 Gy(RBE)). The average D_2% for the spinal cord was 25.1 ± 8.5 Gy(RBE) for protons and 47.6 ± 1.4 Gy(RBE) for VMAT. The average D_2% for chiasm was 46.5 ± 4.4 Gy(RBE) for protons and 50.8 ± 1.4 Gy(RBE) for VMAT, respectively. Robust evaluation was performed and showed the least robust plans for plans with a low number of beams.Discussion: In conclusion, several influences on harmonization were identified: adherence/interpretation to/of the protocol, available technology, experience in treatment planning and use of different beam arrangements. In future, all OARs that should be included in the optimization need to be specified in order to further harmonize treatment planning.

Clinical results of proton therapy reirradiation for recurrent nasopharyngeal carcinoma

Background and purpose: Recurrent nasopharyngeal carcinoma (NPC) has limited curative treatment options. Reirradiation is the only potential definitive treatment in advanced stages at a cost of substantial severe and often life-threatening toxicity. Proton therapy (PT) reduces irradiated volume compared with X-ray radiotherapy and could be advantageous in terms of safety and efficacy in a population of heavily pretreated patients. We report the retrospective results of PT reirradiation in recurrent NPC patients treated at our Institution Methods: All recurrent NPC patients treated since the beginning of clinical activity entered the present analysis. Clinical target volume consisted of Gross Tumor volume plus a patient-specific margin depending on disease behavior, tumor location, proximity of organs at risk, previous radiation dose. No elective nodal irradiation was performed. Active scanning technique with the use of Single Field Optimization (SFO) or Multifield Optimization (MFO) was adopted. Cumulative X-ray -PT doses were calculated for all patients using a dose accumulation tool since 2016. Treatment toxicity was retrospectively collected. Results: Between February 2015, and October 2018, 17 recurrent NPC patients were treated. Median follow-up (FUP) was 10 months (range 2-41). Median PT reirradiation dose was 60 Gy RBE (range 30.6-66). The majority of patients (53%) underwent concomitant chemotherapy. Acute toxicity was low with no ≥ G3 adverse events. Late events ≥ G3 occurred in 23.5% of patients. Most frequent late toxicity was hearing impairment (17,6%). G2 soft tissue necrosis occurred in two patients. Fatal bleeding of uncertain cause (either tumor recurrence or G5 carotid blowout) occurred in one patient. Kaplan-Meier 18 months Overall Survival (OS) and Local control (LC) rates were 54.4% and 66.6%, respectively. Conclusions: Our initial results with the use of modern PT for reirradiation of recurrent NPC patients are encouraging. Favorable LC and OS rates were obtained at the cost of acceptable severe late toxicity.

Results of Whole Brain Radiation Therapy in Patients with Brain Metastases from Colorectal Carcinoma

Aims and background

Carcinoma of the colon-rectum is an infrequent cause of brain metastases, constituting 1-5% of all metastatic lesions to the brain. We reviewed our experience in the treatment of brain metastases from colorectal cancer to define the efficacy of whole brain radiation therapy as a palliative measure in this setting of patients.

Methods

Twenty-three consecutive cases of brain metastasis from colorectal cancer treated between 1999 and 2004 were identified in the files of the Division of Radiotherapy of the A Businco Regional Oncological Hospital, Cagliari. Their records were reviewed for patient and tumor characteristics and categorized according to the RTOG RPA classes.

Results

Fifteen patients (65%) had multiple metastases. Twenty-one patients (91%) showed extracranial metastases. Fourteen patients were classified as RTOG RPA class II and 9 class III. The median radiation dose delivered was 2000 cGy in 5 fractions in one week (range, 20-36 Gy). In 14 of 20 assessable patients (70%), symptomatic improvement was observed. The median follow-up and survival time for all the patients, 12 females and 11 males, was 3 months. In 3 patients only the cause of death was the brain metastasis.

Conclusions

Despite the disappointing survival time, external radiation therapy to the whole brain proved to be an efficacious palliative treatment for patients with multiple or inoperable brain metastasis from colorectal cancer.

Potential skin morbidity reduction with intensity-modulated proton therapy for breast cancer with nodal involvement

Background: Different modern radiation therapy treatment solutions for breast cancer (BC) and regional nodal irradiation (RNI) have been proposed. In this study, we evaluate the potential reduction in radiation-induced skin morbidity obtained by intensity modulated proton therapy (IMPT) compared with intensity modulated photon therapy (IMXT) for left-side BC and RNI. Material and Methods: Using CT scans from 10 left-side BC patients, treatment plans were generated using IMXT and IMPT techniques. A dose of 50 Gy (or Gy [RBE] for IMPT) was prescribed to the target volume (involved breast, the internal mammary, supraclavicular, and infraclavicular nodes). Two single filed optimization IMPT (IMPT₁ and IMPT₂) plans were calculated without and with skin optimization. For each technique, skin dose-metrics were extracted and normal tissue complication probability (NTCP) models from the literature were employed to estimate the risk of radiation-induced skin morbidity. NTCPs for relevant organs-at-risk (OARs) were also considered for reference. The non-parametric Anova (Friedman matched-pairs signed-rank test) was used for comparative analyses. Results: IMPT improved target coverage and dose homogeneity even if the skin was included into optimization strategy (HI_IMPT2 = 0.11 vs. HI_IMXT = 0.22 and CI_IMPT2 = 0.96 vs. CI_IMXT = 0.82, p < .05). A significant relative skin risk reduction (RR = NTCP_IMPT/NTCP_IMXT) was obtained with IMPT₂ including the skin in the optimization with a RR reduction ranging from 0.3 to 0.9 depending on the analyzed skin toxicity endpoint/model. Both IMPT plans attained significant OARs dose sparing compared with IMXT. As expected, the heart and lung doses were significantly reduced using IMPT. Accordingly, IMPT always provided lower NTCP values. Conclusions: IMPT guarantees optimal target coverage, OARs sparing, and simultaneously minimizes the risk of skin morbidity. The applied model-based approach supports the potential clinical relevance of IMPT for left-side BC and RNI and might be relevant for the setup of cost-effectiveness evaluation strategies based on NTCP predictions, as well as for establishing patient selection criteria.

Stage I Seminoma of the Testis: Long Term Results and Toxicity with Adjuvant Radiotherapy

Aims and background

Pure testicular seminoma has historically been treated with post-orchidectomy radiation therapy with excellent results. Recently, several aspects of the treatment of stage I seminoma have been questioned. We assessed long-term results and toxicity of patients with pure testicular seminoma treated at the Department of Radiation Oncology of S. Chiara Hospital, Trento.

Methods

From 1953 to 1987, 102 patients with stage I pure testicular seminoma were given megavoltage irradiation with curative intent. All patients had a minimum follow-up of 3 years (maximum 37 years, median 13 years). They received a mean para-aortic/pelvic dose of 33.07 Gy (range 23.70-45.20 Gy) with different doses and fields reflecting the change in techniques over a long period of time.

Results

The cause-specific actuarial survival at 30 years was 99% and crude survival 67%. One patient had an out-field relapse (inguinal) after a few months and was cured with radiotherapy and chemotherapy. Another patient relapsed with widespared metastases and died after 1 year of progressive disease. Early toxycity was mild and the treatment was well tolerated. Late side effects were reported in 8/102 patients.

Conclusion

In our series adjuvant radiation therapy resulted in cure rates corresponding to those reported in the literature. The 30-year actuarial survival of 99% was extremely good and the toxicity of the treatment was mild. Post-orchidectomy radiation to the para-aortic and ipsilateral pelvic nodes is a safe and effective method of preventing recurrences and is currently to be considered the treatment of choice in stage I testicular seminoma.

Small Cell Carcinoma of the Urinary Bladder. Report of two Cases and Review of the Literature

Undifferentiated small cell carcinoma of the bladder is a rare but aggressive subset of urinary tract neoplasms. Analogous to small-cell carcinoma of the lung, this tumor frequently exhibits neuroendocrine differentiation. We report the 92nd and 93rd case of small cell carcinoma of the bladder reported in the literature with characteristic cytologic, histologic, histochemical, and ultrastructural features. The patients were treated initially with chemotherapy, but after a brief clinical course died for progression of disease and for myocardial infarction, respectively. The pathologic and clinical features and therapeutic options of the cases described in the literature are reviewed.

Comparative Evaluation of Two Hypofractionated Radiotherapy Regimens for Painful Bone Metastases

Aims and background

In 75% of the patients with bone metastases (BM) pain is the dominant symptom. Radiotherapy (XRT) plays a major role in the palliation of pain in patients with BM. Several schedules of short and long fractionation XRT are used in clinical practice, with hypofractionated treatments being even more attractive for practical reasons. A considerable body of evidence supports the clinical use of short schedules and single-dose XRT. We retrospectively evaluated the efficacy of two short fractionated schedules of 8 Gy as a single dose and 20 Gy in 5 fractions in relieving pain in patients with multiple uncomplicated BM.

Method

From January to December 2001, 130 patients with 146 painful BM were treated with palliative localized XRT. There were 42 males and 88 females with a median age of 58 years (range 28–84). The commonest sites of treatment were the spine (59.6%) and pelvis (14.4%). The primary endpoint was clinically significant pain relief in the first six months of follow-up evaluated with the IAEA (International Atomic Energy Agency) pain measurement score measuring pain severity and pain frequency. Analgesic use was also recorded before and after treatment as drug frequency and drug severity. Patients with painful BM from any primary tumor site were irradiated. Treatment schedules consisted of a course of XRT with 4 Gy/fraction/day (total dose: 20 Gy/5 fractions) (group A, 59 lesions) or with a single dose of 8 Gy (group B, 87 lesions).

Results

There was no significant difference in complete response (CR) rates between treatment schedules: complete pain relief was achieved in 17/59 lesions (29%) in the fractionated group and in 29/87 lesions (33%) in the single-dose group. Also the overall response (complete + partial) was similar: 35/59 lesions (60%) in group A and 60/87 (69%) in group B. The minimum, maximum and median follow-up was 3, 23, and 9 months, respectively, for group A and 3, 20, and 11 months for group B. The actuarial median duration of pain relief was similar: 4.5 months in group A and 4 months in group B. No particular side effects were recorded in either group.

Conclusions

There were no differences between the two fractionation schedules used in our study with regard to pain relief and use of analgesics. Palliation of pain was obtained in approximately two thirds of patients with both schedules, providing further evidence of the similar efficacy between single and multiple fractions. With regard to pain response these data justify a recommendation for the use of a more simple and convenient 8 Gy single fraction for the palliation of uncomplicated BM.

Choroidal Metastasis from Carcinoma of the Hypopharynx: A Case Report

Choroidal metastasis from primaries other than breast or lung cancer is a rare event. There is no documented case in the literature of choroidal metastases in patients with hypopharynx carcinoma. Early treatment with radiation therapy provides effective palliation by preserving visual function and preventing the need for enucleation. Chemotherapy alone does not seem to be as effective as radiation therapy for patients with choroidal metastases. In this paper a case of choroidal metastasis arising from a primary hypopharynx carcinoma is presented.

Subclinical Ductal Carcinoma in Situ of the Breast: Treatment with Conservative Surgery and Radiotherapy

Aims and Background

In spite of the fact that ductal carcinoma in situ (DCIS) of the breast is a frequently encountered clinical problem, there is no consensus about the optimal treatment of clinically occult (i.e., mammographic presentation only) DCIS. Interest in breast conservation therapy has recently increased. Few data are available in Italy on the conservative treatment with surgery and adjuvant postoperative radiotherapy.

Methods

A retrospective multi-institutional study was performed in 15 Radiation Oncology Departments in northern Italy involving 112 women with subclinical DCIS of the breast treated between 1982 and 1993. Age of the patients ranged between 32 and 72 years (median, 50 years). All of them underwent conservative surgery: quadrantectomy in 89, tumorectomy in 11, and wide excision in 12 cases. The most common histologic subtype was comedocarcinoma (37%). The median pathologic size was 10 mm (range 1 to 55 mm). Axillary dissection was performed in 83 cases: all the patients were node negative. All the patients received adjunctive radiation therapy with 60Co units (77%) or 6 MV linear accelerators (23%) for a median total dose to the entire breast of 50 Gy (mean, 49.48 Gy; range, 45-60 Gy). Seventy-six cases (68%) received a boost to the tumor bed at a dose of 8-20 Gy (median 10 Gy) for a minimum tumor dose of 58 Gy.

Results

At a median follow-up of 66 months, 8 local recurrences were observed, 4 intraductal and 4 invasive. All recurrent patients had a salvage mastectomy and are alive and free of disease at this writing. The 10-year actuarial overall, cause-specific, and recurrence-free survival was of 98.8%, 100%, and 91%, respectively.

Conclusions

The retrospective multicentric study, with a local control rate of more than 90% at 10 years with 100% cause-specific survival, showed that conservative surgery and adjuvant radiation therapy is a safe and efficacious treatment for patients with occult, non-palpable DCIS.

Clinical Characteristics, Diagnosis and Treatment of Elderly Patients with Lung Cancer at Non-Surgical Institutions: A Multicenter Study

A multicenter retrospective study was undertaken in northern Italy to assess clinical characteristics and pattern of care of elderly patients (> 70 years) with lung cancer seen in 1984, at 14 non-surgical institutions. Overall, 1 out of 5 patients with lung cancer was elderly. Eighty-four percent of the 264 elderly patients under study were males, and overall, their median age was 76 years. Squamous cell carcinoma was the most frequent histologic type (53%), and most of the patients (61%), after a rather intensive diagnostic workup, had loco-regional disease. Sixty-three percent of patients underwent radiotherapy, which was mostly classified as palliative. Chemotherapy was given to 13% of patients, mostly with small cell histology. Response to radiotherapy and chemotherapy was observed in about 50% of the patients; however, 3 out of 34 (10%) patients treated with chemotherapy died from toxicity. The median survival time from diagnosis was 9.9 months; survival time was not related, in this population of elderly patients, to age. Throughout the study, the quality of data recording during the patient's illness was often found to be suboptimal. In conclusion, elderly patients with lung cancer appear to be actively staged and treated outside a protocol context in the clinical practice of cooperating nonsugical institutions in northern Italy. This stresses the importance of prospective studies aimed to evaluate the cost/effectiveness of the various procedures used and the impact of treatments used (or even of a policy of no treatment) on the survival and quality of life of these patients.

Treatment Patterns in Elderly Patients (≥70 YEARS) with Breast Carcinoma. A Retrospective Study of the Gruppo Oncologico Clinico Cooperativo del Nord-est (Goccne)

The pattern of treatment used in elderly women affected by breast carcinoma was evaluated in a retrospective study by the North-East Clinical Cooperative Group in Italy (GOCCNE). Six divisions were involved in the study. The medical records of 115 elderly women were reviewed; the women's median age was 75 years (range, 70-93). Surgery was used in 70/72 operable patients (97 %), although limited surgery plus radiotherapy was used in only 7.5 %. Most stage II patients were treated with adjuvant tamoxifen, as were younger postmenopausal patients, according to the guidelines of the Bethesda Consensus Meeting. Comorbid conditions are of particular concern in therapy planning, considering that more stage III patients died of competing causes than for disease progression. The role of chemotherapy was very marginal.

Quality of Life in Patients with Early Stage Breast Carcinoma Treated with Conservation Surgery and Radiotherapy. An Italian Monoinstitutional Study

Aims

To evaluate the quality of life (QOL) in patients with early stage invasive carcinoma of the breast treated with conservative surgery and postoperative irradiation.

Methods

A mailed survey to examine QOL was conducted in 227 subjects with breast cancer treated in 1990 and 1994 with conservation surgery plus definitive irradiation. The self-compiled questionnaire was developed based on a series of 38 items assessing six core areas of QOL. Furthermore, the patients were requested to evaluate the degree of information provided by the medical staff concerning the disease, the treatment and related side effects and to evaluate the effects of the treatment on their social, overall QOL, and health status.

Results

The questionnaire was completed by 156 patients (68.7%) who had a median age of 56 years (range, 28–75 years) at the time of treatment and 59 years (range, 31–82 years) at the time of the study. The physical condition was reported to be good. Data relating to sexual life were provided by more than 90% of the patients. Some limitations in sexuality, some interference with sexual desire, and some modifications during intercourse were reported by 11, 11, and 10 patients, respectively. The subjective evaluations of the cosmetic results of the therapies were judged good-excellent by 56% of the patients, 12 (8%) only had a negative perception of their body image. Twenty-five percent of the sample declared that they felt tense, 19% nervous, 18% lonely, 27% anxious and 16% depressed. Only six patients (4%) declared that the treatment had had a bad on their social life, and 18 (11%) thought that their health status has been affected by the treatment. A worsening of QOL due to the disease or the treatment was reported by 8% of the responders. The amount of information received concerning the treatment and its side effects was considered sufficient by most of the patients.

Conclusions

The results of the study revealed a satisfactory health-related QOL in patients treated with breast conservation and postoperative irradiation. A preserved favorable body image and lack of a negative impact on sexuality was observed, even though about half of the patients reported a negative judgement on esthetic outcome. Some patients had persistent psychosocial concerns. No significant additional problems attributable to radiation therapy capable of affecting QOL outcomes were reported.

Local Microwave Hyperthermia in Cancer Therapy. Preliminary Report

From February 1981 to September 1981, 16 patients (19 fields) with histologically proven malignancy (10 squamous carcinoma, 4 melanoma, 1 adenocarcinoma, 1 chordoma) were treated with hyperthermia combined with radiotherapy or chemotherapy (1 patient). There were 5 females and 11 males; average age was 65 years, range 45 to 94 years; 15 patients had a Karnofsky index greater than 50%. Hyperthermia (42.5 44.0 °C) was induced by 250 MHz to 1 GHz microwaves (BSD - 1000 Unit). Thermometry was performed by means of non-perturbing probes placed in intratumorally inserted catheters and by measurement of skin temperatures. After hyperthermia plus radiotherapy (18 fields), 9 patients showed 100% response, 5 a volume regression of more than 50%, 3 less than 50% and 1 no change. After chemotherapy plus hyperthermia, 1 patient showed no change. No significant side effects were observed (3 skin burns in 147 hyperthermia treatment sessions).