Patterns of failure in patients receiving definitive and postoperative IMRT for head-and-neck cancer

PURPOSE

To analyze the patterns of locoregional failure in patients with head-and-neck cancer treated with inverse planning intensity-modulated radiotherapy (IMRT).

METHODS AND MATERIALS

Between February 1997 and December 2000, 165 patients with histologically confirmed head-and-neck cancer were treated using a parotid-sparing inverse planning IMRT protocol. Thirty-nine patients who received either palliative repeat irradiation or IMRT as a boost were excluded from this analysis, leaving 126 patients for this analysis. Of the 126 patients, 30 were women and 96 were men (median age 56 years, range 13-84). Fifty-two patients (41%) received definitive IMRT. Of the 52 patients, 17 were treated with RT alone and 35 with concurrent cisplatin-based chemotherapy regimens. Seventy-four patients (59%) received postoperative IMRT. The median follow-up was 26 months (range 12-55). IMRT was used only in the upper neck for salivary sparing. The lower neck was treated with a conventional AP low-neck port abutted to the inferior IMRT dose distribution border. The radiation dose was prescribed to the two clinical target volumes (CTVs) according to the assumed risk of containing disease. The mean dose for definitive IMRT patients was 72.64 +/- 4.83 Gy to CTV1 and 64.34 +/- 5.15 Gy to CTV2. The mean dose to CTV1 and CTV2 in postoperative cases was 68.53 +/- 4.71 Gy and 60.95 +/- 5.33 Gy, respectively. The locations of failure were analyzed.

RESULTS

Seventeen locoregional failures (persistent or recurrent disease) were found. Of these 17 failures, 9 (53%) were inside CTV1. One failure (6%) was marginal to CTV1 but inside CTV2. One failure (6%) occurred outside CTV1 but inside CTV2. Another failure was marginal to CTV2. Of the 17 failures, 5 (28%) were found outside of the IMRT field and in the lower neck. Dose-volume histogram analysis revealed that for all but 1 patient, the recurrent/persistent disease within the CTVs received comparable or superior dose coverage relative to the CTV. The 2-year actuarial locoregional control rate was 85%, and the ultimate locoregional control rate after surgical salvage was 89%. We observed no dermal failure and only one marginal failure in the region adjacent to the spared parotid glands.

CONCLUSION

We have shown that the target definition and coverage for patients treated with IMRT for parotid sparing is adequate. The predominant tumor failure within CTV1 may imply the need to identify patients with radioresistant tumor subvolumes (such as hypoxic regions) within the CTV. This information would assist in discriminating a subgroup of tumors for a more aggressive and target-specific therapeutic approach.

Determination and delineation of nodal target volumes for head-and-neck cancer based on patterns of failure in patients receiving definitive and postoperative IMRT

PURPOSE

We present the guidelines for target volume determination and delineation of head-and-neck lymph nodes based on the analysis of the patterns of nodal failure in patients treated with intensity-modulated radiotherapy (IMRT).

METHODS AND MATERIALS

Data pertaining to the natural course of nodal metastasis for each head-and-neck cancer subsite were reviewed. A system was established to provide guidance for nodal target volume determination and delineation. Following these guidelines, 126 patients (52 definitive, 74 postoperative) were treated between February 1997 and December 2000 with IMRT for head-and-neck cancer. The median follow-up was 26 months (range 12-55), and the patterns of nodal failure were analyzed.

RESULTS

These guidelines define the nodal target volume based on the location of the primary tumor and the probability of microscopic metastasis to the ipsilateral and contralateral (Level I-V) nodal regions. Following these guidelines, persistent or recurrent nodal disease was found in 6 (12%) of 52 patients receiving definitive IMRT, and 7 (9%) of 74 patients receiving postoperative IMRT had failure in the nodal region.

CONCLUSION

On the basis of our clinical experience in implementing inverse-planning IMRT for head-and-neck cancer, we present guidelines using a simplified, but clinically relevant, method for nodal target volume determination and delineation. The intention was to provide a foundation that enables different institutions to exchange clinical experiences in head-and-neck IMRT. These guidelines will be subject to future refinement when the clinical experience in head-and-neck IMRT advances.

Intensity-modulated radiation therapy for oropharyngeal carcinoma: impact of tumor volume

PURPOSE

To assess the therapeutic outcomes in oropharyngeal cancer patients treated with intensity-modulated radiotherapy (IMRT) and analyze the impact of primary gross tumor volume (GTV) and nodal GTV (nGTV) on survival and locoregional control rates.

METHODS AND MATERIALS

Between February 1997 and September 2001, 74 patients with squamous cell carcinoma of the oropharynx were treated with IMRT. Thirty-one patients received definitive IMRT; 17 also received platinum-based chemotherapy. Forty-three patients received combined surgery and postoperative IMRT. The median follow-up for all patients was 33 months (range, 9-60 months). Fifty-two patients (70.3%) had Stage IV disease, 17 patients (23%) had Stage III, 3 patients (4.1%) had Stage II, and 2 patients (2.7%) had Stage I tumors. The mean prescription dose was 70 and 66 Gy, respectively, for the definitive and postoperative cohorts. The daily fraction dose was either 1.9 or 2 Gy, five times weekly. The GTV and/or nGTV were determined and derived using the Computational Environment for Radiotherapy Research, a free software package developed at Washington University. The mean GTV was 30.5 +/- 22.3 cm(3), and the mean nGTV was 23.2 +/- 20.6 cm(3).

RESULTS

Ten locoregional failures were observed. Six patients died of disease and three died of concurrent disease. Distant metastasis developed in 6 patients. The 4-year estimate of overall survival was 87%, and the 4-year estimate of disease-free survival was 81% (66% in the definitive vs. 92% in the postoperative RT group). The 4-year estimate of locoregional control was 87% (78% in the definitive vs. 95% in the postoperative RT group); the 4-year estimate of distant metastasis-free survival was 90% (84% in the definitive vs. 94% in the postoperative group). Multivariate analysis showed that GTV and nGTV were independent risk factors determining locoregional control and disease-free survival for definitive oropharyngeal IMRT patients. The worst late toxicities documented were as follows: 32 patients with Grade 1 and 9 with Grade 2 xerostomia; 2 with Grade 1 and 1 with Grade 2 skin toxicity; 3 with Grade 1 late mucositis; and 3 with Grade 1 trismus. Seventeen patients required gastrostomy tube placement.

CONCLUSION

IMRT is an effective treatment modality for locally advanced oropharyngeal carcinoma. The GTV and nGTV are the most important factors predictive of therapeutic outcome.

Carcinoma of paranasal sinuses: long-term outcomes with radiotherapy

PURPOSE

To assess the clinical features, prognostic factors, results, and complications of treatment of carcinomas of the paranasal sinus.

METHODS AND MATERIALS

The records of 106 patients (72 men and 34 women) with paranasal sinus carcinoma treated with curative intent at Washington University between January 1960 and August 1998 were analyzed. Patient age ranged from 29 to 91 years (median, 64 years). Most tumors originated in the maxillary (76%) or ethmoid (18%) sinus. Most tumors were locally advanced at presentation. All patients underwent radiotherapy (RT), combined with surgery in 65%; 2% received chemotherapy.

RESULTS

Follow-up ranged from 1.7 months to 24 years (median 5 years). The 5-year local tumor control, locoregional tumor control, disease-free survival (DFS), and overall survival rate was 58%, 39%, 33%, and 27%, respectively. A statistically significant improvement in DFS was noted with the addition of surgical resection to RT (35% vs. 29%, p = 0.05). Nodal status at presentation emerged as a statistically significant predictor for locoregional tumor control and DFS in multivariate analysis. Distant metastases occurred in 29% of patients.

CONCLUSION

This review of a large, single-institution experience of paranasal sinus carcinoma patients who underwent RT showed that locoregional tumor progression and recurrence remain predominant patterns of failure despite aggressive local treatment with combined surgery and RT. DFS improved slightly with combined modality treatment. The overall survival rates remained suboptimal, suggesting a need for more accurate determination of tumor extent, as well as more effective locoregional and systemic therapies.

The results of surgery, with or without radiotherapy, for primary spinal myxopapillary ependymoma: a retrospective study from the rare cancer network

PURPOSE

The aim of this study was to assess the outcome of patients with primary spinal myxopapillary ependymoma (MPE).

MATERIALS AND METHODS

Data from a series of 85 (35 females, 50 males) patients with spinal MPE were collected in this retrospective multicenter study. Thirty-eight (45%) underwent surgery only and 47 (55%) received postoperative radiotherapy (RT). Median administered radiation dose was 50.4 Gy (range, 22.2-59.4). Median follow-up of the surviving patients was 60.0 months (range, 0.2-316.6).

RESULTS

The 5-year progression-free survival (PFS) was 50.4% and 74.8% for surgery only and surgery with postoperative low- (<50.4 Gy) or high-dose (>or=50.4 Gy) RT, respectively. Treatment failure was observed in 24 (28%) patients. Fifteen patients presented treatment failure at the primary site only, whereas 2 and 1 patients presented with brain and distant spinal failure only. Three and 2 patients with local failure presented with concomitant spinal distant seeding and brain failure, respectively. One patient failed simultaneously in the brain and spine. Age greater than 36 years (p = 0.01), absence of neurologic symptoms at diagnosis (p = 0.01), tumor size >or=25 mm (p = 0.04), and postoperative high-dose RT (p = 0.05) were variables predictive of improved PFS on univariate analysis. In multivariate analysis, only postoperative high-dose RT was independent predictors of PFS (p = 0.04).

CONCLUSIONS

The observed pattern of failure was mainly local, but one fifth of the patients presented with a concomitant spinal or brain component. Postoperative high-dose RT appears to significantly reduce the rate of tumor progression.

A simple strategy to decrease fatal carotid blowout syndrome after stereotactic body reirradiaton for recurrent head and neck cancers

BACKGROUND

This study aimed to compare the therapeutic outcomes and fatal carotid blow out syndrome (CBOS) incidence rates between two different stereotactic body radiotherapy (SBRT) protocols.

METHODS

The study included 75 patients with inoperable locally recurrent head and neck cancer treated with SBRT in our department between June 2007 and March 2011. The first 43 patients were treated sequentially (group I). Then our SBRT protocol was changed due to the high rate of CBOS, and the following 32 patients were treated every other day in a prospective institutional protocol (group II).

RESULTS

Median overall survival in group I and group II was 11 months and 23 months, respectively (P = 0.006). We observed 11 cases of CBOS. Only 1 of 7 patients (14%) with CBOS survived in group I, whereas 2 of 4 patients (50%) in group II remain alive. CBOS free median overall survivals were 9 months, and 23 months in group I and group II respectively (P = 0.002). The median radiation dose received by the carotid artery in patients with CBOS was 36.5 Gy (range: 34-42.8 Gy), versus 34.7 Gy (range: 0-44 Gy) in the patients that didn't have CBOS (P = 0.15). CBOS did not occur in any of the patients with a maximum carotid artery radiation dose <34 Gy.

CONCLUSIONS

Every other day SBRT protocol for re-irradiation of recurrent head and neck cancer is promising in terms of decreasing the incidence of fatal CBOS.

A retrospective comparison of robotic stereotactic body radiotherapy and three-dimensional conformal radiotherapy for the reirradiation of locally recurrent nasopharyngeal carcinoma

PURPOSE

We assessed therapeutic outcomes of reirradiation with robotic stereotactic radiotherapy (SBRT) for locally recurrent nasopharyngeal carcinoma (LRNPC) patients and compared those results with three-dimensional conformal radiotherapy (CRT) with or without brachytherapy (BRT).

METHODS AND MATERIALS

Treatment outcomes were evaluated retrospectively in 51 LRNPC patients receiving either robotic SBRT (24 patients) or CRT with or without BRT (27 patients) in our department. CRT was delivered with a 6-MV linear accelerator, and a median total reirradiation dose of 57 Gy in 2 Gy/day was given. Robotic SBRT was delivered with CyberKnife (Accuray, Sunnyvale, CA). Patients in the SBRT arm received 30 Gy over 5 consecutive days. We calculated actuarial local control and cancer-specific survival rates for the comparison of treatment outcomes in SBRT and CRT arms. The Common Terminology Criteria for Adverse Events v3.0 was used for toxicity evaluation.

RESULTS

The median follow-up was 24 months for all patients. Two-year actuarial local control rates were 82% and 80% for SBRT and CRT arms, respectively (p = 0.6). Two-year cancer-specific survival rates were 64% and 47% for the SBRT and CRT arms, respectively (p = 0.4). Serious late toxicities (Grade 3 and above) were observed in 21% of patients in the SBRT arm, whereas 48% of patients had serious toxicity in the CRT arm (p = 0.04). Fatal complications occurred in three patients (12.5%) of the SBRT arm, and four patients (14.8%) of the CRT arm (p = 0.8). T stage at recurrence was the only independent predictor for local control and survival.

CONCLUSION

Our robotic SBRT protocol seems to be feasible and less toxic in terms of late effects compared with CRT arm for the reirradiation of LRNPC patients.

Comparison of intracavitary brachytherapy and stereotactic body radiotherapy dose distribution for cervical cancer

PURPOSE

To compare the dose distribution characteristics of stereotactic body radiotherapy (SBRT) with intracavitary high-dose-rate (HDR) brachytherapy in patients with cervical carcinoma.

METHODS AND MATERIALS

HDR intracavitary brachytherapy treatment plans for 11 women with cervical carcinoma were evaluated in this analysis. The total HDR brachytherapy dose was 28Gy given in four fractions. HDR brachytherapy was delivered with the microSelectron HDR therapy unit (Nucletron B. V., Veenendaal, The Netherlands). SBRT plans for each patient were generated with MultiPlan for CyberKnife Robotic Radiosurgery System (Accuray Inc., Sunnyvale, CA). The dose distributions, dose-volume histograms, and maximum dose points of the target and critical organs were recorded for both plans.

RESULTS

SBRT yielded significantly better target coverage; the median target coverage for the 100% isodose line was 50.7% for HDR brachytherapy plans, whereas it was 99.1% for SBRT plans. The dose distributions for critical organs were similar in both types of plans. The exceptions were the 25% isodose being significantly better in brachytherapy plans for rectum, and the 100% isodose exposure being higher in brachytherapy plans for rectum, bladder, and sigmoid colon. Some significant differences were also found in maximum doses received by a 2-cc volume of bladder in favor of SBRT plans. In addition, maximum bone marrow doses were significantly higher in SBRT plans.

CONCLUSION

SBRT plans achieved better target coverage and better dose distributions to critical organs except bone marrow compared with HDR brachytherapy plans in patients with locally advanced cervical cancer.

Health-related quality of life in high-grade glioma patients: a prospective single-center study

PURPOSE

In this single center study, we aimed to assess quality of life and cognitive and emotional distress in patients treated for high-grade glioma.

METHODS AND MATERIALS

A hundred and eighteen patients with high-grade glioma were prospectively enrolled. We assessed HRQoL at baseline (after surgery before radiotherapy), at the end of radiotherapy and during follow-up (every 3 months for the first 2 years and every 6 months between 2 and 5 years) using the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire 30 (EORTC-C30), Brain Cancer Module-20 (BN-20), Minimental State Examination (MMSE) and Hospital Anxiety and Depression Scale (HADS). Baseline scores, and first 18-month follow-up period scores were included to statistical analysis.

RESULTS

Sixty-five (55%) patients had progressive tumor. Global score, physical, role and emotional function, insomnia (p for each <0.001) and appetite loss (p: 0.008) scores of EORTC-C30 significantly related to disease progression. According to BN-20 seizure and leg weakness (p < 0.001), drowsiness and bladder control (p: 0.002), motor dysfunction (p: 0.001), future uncertainty (p: 0.04), visual disorder (p: 0.008) and communication deficit (p: 0.006) symptoms significantly related to disease progression. There were significant decrements in orientation, attention and calculation and language scores (p values were 0.017, 0.005 and 0.003, respectively) of MMSE. The baseline and follow-up anxiety and depression scores did not differ significantly.

CONCLUSION

We conclude that there were many changes in patients with high-grade glioma during the course of the disease and most of them were related to disease progression.

Hypofractionated stereotactic reirradiation for recurrent glioblastoma

Treatment choices for recurrent glioblastoma patients are sparse and the results are not satisfactory. In this retrospective analysis, we evaluated the results of re-irradiation of locally recurrent glioblastoma patients with an image-guided, fractionated, frameless stereotactic radiotherapy (SRT) technique. We treated 37 patients with the diagnosis of recurrent glioblastoma from September 2009 to December 2011. SRT was performed in a median five fractions (range, 1-5 fractions) with CyberKnife(®) (Accuray Incorporated, Sunnyvale, CA, USA). The dose given ranged from 14 to 32 Gy (median, 30 Gy). The median volume of the GTV was 24 cc (range, 2-81 cc). Median follow-up was 9.3 months. Five patients had regression in their lesions, 14 had stable disease, progression was observed in eight patients, and seven patients had pseudoprogression. The median survival following SRT was 10.6 months (range, 1.1-20 months) and overall survival following initial treatment was 35.5 months. The time to progression following SRT was 7.9 months in median. Patients with pseudoprogression had significantly longer survival after the first magnetic resonance imaging (MRI) compared to those with regression, stable or progressive disease (p = 0.012). The median survival after SRT for patients with pseudoprogression was 20 months. Patients who had GTV <24 cc had significantly longer survival following SRT compared to those with lesions ≥24 cc (p = 0.015). Patients who had chemotherapy after SRT had a median survival of 16.8 months. This was 9.7 months for patients who were not prescribed any chemotherapy (p = 0.062).

Percent positive axillary lymph node metastasis predicts survival in patients with non-metastatic breast cancer

PURPOSE

We retrospectively evaluated the impact of percent positive axillary nodal involvement on the therapeutic outcomes in patients with non-metastatic breast cancer receiving postmastectomy radiotherapy and chemotherapy.

MATERIALS AND METHODS

Between January 1994 and December 2002, the medical records of 939 eligible non metastatic breast carcinoma patients were analyzed. Chest wall radiotherapy was indicated in case of positive surgical margin, tumor size equal or more than 4 cm, skin-fascia invasion. Lymphatic irradiation was applied for more than three metastatic axillary lymph nodes, incomplete axillary dissection (<10 lymph nodes), extracapsular extension or perinodal fat tissue invasion. A total dose of 50 Gy was given to chest wall and lymph node regions with 2 Gy daily fractions. Statistical analyses were performed by Kaplan-Meier method, Log-rank test and Cox's regression analysis.

RESULTS

The median follow-up for all patients alive was 62 months. The 5-year overall survival (OS) and disease-free survival (DFS) for entire cohort were 81%, and 65%, respectively. Univariate analysis for OS revealed significance for tumour size (< or =5 cm vs. >5 cm, p<0.001), metastatic nodal involvement (0 vs. 1-3 vs. >4 LN, p<0.001), percent positive nodal involvement ([metastatic nodes/total nodes removed] x 100; 0 vs. < or =25% vs. 26-50% vs. >50%, p<0.001), surgical margin status (negative vs. positive, p=0.05), and hormonal treatment (present vs. absent, p=0.03). DFS had similarly significance for age (< or =40 years vs. >40 years, p=0.006), tumour size (0.02), metastatic nodal involvement (p<0.001), percent positive nodal involvement (p<0.001), and perinodal invasion (present vs. absent, p=0.01). Multivariate analysis revealed significance for tumour size, percent positive nodal involvement, hormonal treatment, and surgical margin status for OS. Age and percent positive nodal involvement were found to be significant for DFS.

CONCLUSION

Percent positive nodal involvement was found to be a significant prognostic factor for survival in all end-points.

Vaginal high dose rate brachytherapy alone in patients with intermediate- to high-risk stage I endometrial carcinoma after radical surgery

The objective of this study was to analyze the efficacy and morbidity of vaginal cuff brachytherapy alone in intermediate- to high-risk stage I endometrial cancer patients after complete surgical staging. Between October 1994 and November 2005, 128 patients with intermediate- to high-risk stage I endometrial adenocarcinoma were treated with high dose rate (HDR) brachytherapy alone after complete surgical staging. The intermediate- to high-risk group was defined as any stage I with grade 3 histology or stage IB grade 2 or any stage IC disease. The comprehensive surgery was in the form of total abdominal hysterectomy, bilateral salpingo-oophorectomy in addition to infracolic omentectomy, and routine pelvic and para-aortic lymphadenectomy. The median number of the lymph nodes dissected was 33. The median age at the time of diagnosis was 60 years. Forty patients were staged as IB (grade 2: 25 and grade 3: 15), and 88 patients were staged as IC (grade 1: 31, grade 2: 41, and grade 3: 16). A total dose of 27.5 Gy with HDR brachytherapy, prescribed at 0.5 cm, was delivered in five fractions in 5 consecutive days. Median follow-up was 48 months. Six (4.7%) patients developed either local recurrence (n = 2) or distant metastases (n = 4). Five-year overall survival and disease-free survival (DFS) rates are 96% and 93%, respectively. Only age was found to be significant prognostic factor for DFS. Patients younger than 60 years have significantly higher DFS (P = 0.006). None of the patients experienced grade 3/4 complications due to the vaginal HDR brachytherapy. Vaginal cuff brachytherapy alone is an adequate treatment modality in stage I endometrial adenocarcinoma patients with intermediate- to high-risk features after complete surgical staging with low complication rates.

Investigating in-field and out-of-field neutron contamination in high-energy medical linear accelerators based on the treatment factors of field size, depth, beam modifiers, and beam type

PURPOSE

We analysed the effects of field size, depth, beam modifier and beam type on the amount of in-field and out-of-field neutron contamination for medical linear accelerators (linacs).

METHODS

Measurements were carried out for three high-energy medical linacs of Elekta Synergy Platform, Varian Clinac DHX High Performance and Philips SL25 using bubble detectors. The photo-neutron measurements were taken in the first two linacs with 18 MV nominal energy, whereas the electro-neutrons were measured in the three linacs with 9 MeV, 10 MeV, 15 MeV and 18 MeV.

RESULTS

The central neutron doses increased with larger field sizes as a dramatic drop off was observed in peripheral areas. Comparing with the jaws-shaped open-field of 10 × 10 cm, the motorised and physical wedges contributed to neutron contamination at central axis by 60% and 18%, respectively. The similar dose increment was observed in MLC-shaped fields. The contributions of MLCs were in the range of 55-59% and 19-22% in Elekta and Varian linacs comparing with 10 × 10 and 20 × 20 cm open fields shaped by the jaws, respectively. The neutron doses at shallow depths were found to be higher than the doses found at deeper regions. The electro-neutron dose at the 18 MeV energy was higher than the doses at the electron energies of 15 MeV and 9 MeV by a factor of 3 and 50, respectively.

CONCLUSION

The photo- and electro-neutron dose should be taken into consideration in the radiation treatment with high photon and electron energies.

Treatment outcomes of metastasis-directed treatment using 68Ga-PSMA-PET/CT for oligometastatic or oligorecurrent prostate cancer: Turkish Society for Radiation Oncology group study (TROD 09-002)

PURPOSE

The aim of this study was to evaluate the outcomes of 68Ga prostate-specific membrane antigen (68Ga-PSMA) positron-emission tomography (PET)/CT-based metastasis-directed treatment (MDT) for oligometastatic prostate cancer (PC).

METHODS

In this multi-institutional study, clinical data of 176 PC patients with 353 lesions receiving MDT between 2014 and 2019 were retrospectively evaluated. All patients had biopsy proven PC with ≤5 metastases detected with 68Ga-PSMA-PET/CT. MDT was delivered with conventional fractionation or stereotactic body radiotherapy (SBRT) techniques. CTCAE v4.0 was used for acute and RTOG/EORTC Late Radiation Morbidity Scoring Schema was used for late toxicity evaluation.

RESULTS

At the time of MDT, 59 patients (33.5%) had synchronous and 117 patients (66.5%) had metachronous metastases. Median number of metastases was one and the MDT technique was SBRT in 73.3% patients. The 2‑year overall survival (OS) and progression-free survival (PFS) rates were 87.6% and 63.1%, respectively. With a median follow-up of 22.9 months, 9 patients had local recurrence at the irradiated site. The 2‑year local control rate at the treated oligometastatic site per patient was 93.2%. In multivariate analysis, an increased number of oligometastases and untreated primary PC were negative predictors for OS; advanced clinical tumor stage, untreated primary PC, BED3 value of ≤108 Gy, and MDT with conventional fractionation were negative predictors for PFS. No patient experienced grade ≥3 acute toxicity, but one patient had a late grade 3 toxicity of compression fracture after spinal SBRT.

CONCLUSION

68Ga-PSMA-PET/CT-based MDT is an efficient and safe treatment for oligometastatic PC patients. Proper patient selection might improve treatment outcomes.

PSA bouncing after short term androgen deprivation and 3D-conformal radiotherapy for localized prostate adenocarcinoma and the relationship with the kinetics of testosterone

OBJECTIVES

To assess the factors effecting PSA bounce and to identify any possible relationship with biochemical control after 3-D conformal radiotherapy (3D-CRT) and total androgen deprivation (TAD) for prostate cancer by evaluating four previously described PSA bounce definitions.

METHODS

Between January 1998 and January 2001, 83 consecutive patients with clinically localized prostate cancer were treated by 3D-CRT with neoadjuvant 3 months and/or 6 months adjuvant TAD. All patients had a pretreatment PSA level, at least eight post-external beam radiotherapy (EBRT) PSA and testosterone levels and minimum two years of follow-up. Total radiotherapy dose was 73.6 Gy at ICRU reference point. Four previous definitions of PSA bounce were used: Critz definition (>or=0.1 ng/mL), Cavanagh definition (>or=0.2 ng/mL), Hanlon definition (>or=0.4 ng/mL) and Rosser definition (>or=0.5 ng/mL) according to original methodology performed to report PSA bounce. Biochemical failure was defined in accordance with the ASTRO consensus guidelines.

RESULTS

The median follow-up time was 40 months. PSA bounce was recorded as follows: Critz definition, 33 patients (40%); Cavanagh definition, 21 patients (25%); Hanlon definition, 11 patients (13%); and Rosser definition, 7 patients (8%). In multivariate analysis, pre-EBRT PSA level and the duration of TAD for Critz definition; age, pre-EBRT PSA and the duration of TAD for Cavanagh definition; age and duration of TAD for Hanlon definition; age and pre-biopsy PSA for Rosser definition were significant independent prognostic factors determining PSA bounce. A significant increase of mean testosterone level in bouncers was detected at the 6th-9th and 18th-21st months. PSA bounce did not predict for PSA failure in multivariate analysis.

CONCLUSIONS

We observed no correlation between biochemical failure and PSA bounce. The longer duration of TAD and older age were found to be inversely proportional with PSA bouncing in this cohort. Notably, recovery of testosterone might cause PSA bouncing.

Stereotactic radiotherapy to oligoprogressive lesions detected with 68Ga-PSMA-PET/CT in castration-resistant prostate cancer patients

PURPOSE

We assessed the outcomes of stereotactic body radiotherapy (SBRT) to treat oligoprogressive castration-resistant prostate cancer (CRPC) patients with ≤5 lesions using gallium prostate-specific membrane antigen-positron emission tomography (68Ga-PSMA-PET/CT).

METHODS

The clinical data of 67 CRPC patients with 133 lesions treated with 68Ga-PSMA-PET/CT-based SBRT were retrospectively analyzed. All of the patients had oligoprogressive disease during androgen-deprivation therapy (ADT). The prognostic factors for overall- (OS) and progression-free survival (PFS) and the predictive factors for switching to next-line systemic treatment (NEST) and NEST-free survival (NEST-FS) were analyzed.

RESULTS

With a median follow-up of 17.5 months, the 2-year overall survival (OS) and PFS rates were 86.9% and 34.4%, respectively. The PSA response was observed in 49 patients (73.1%). Progression was observed in 37 patients (55.2%) at a median of 11.0 months following SBRT. A total of 45 patients (67.2%) remained on ADT after SBRT, and 22 patients (32.8%) had a NEST change at a median of 16.4 months after metastasis-directed treatment (MDT). Patients with a NEST change had higher post-SBRT PSA values and fewer PSA nadirs after MDT than their counterparts. In multivariate analysis, higher pre-SBRT PSA values were the only significant predictor for worse OS and NEST-FS, and no significant factor was found for PFS. No serious acute or late toxicities were observed.

CONCLUSION

This study demonstrated the feasibility of MDT using SBRT to treat oligoprogressive lesions by 68Ga-PSMA-PET/CT in CRPC patients is efficient and well-tolerated, prolonging the effectiveness of ADT by delaying NEST.

Stereotactic Radiosurgery and Fractionated Stereotactic Radiation Therapy for the Treatment of Uveal Melanoma

PURPOSE

To evaluate treatment results of stereotactic radiosurgery or fractionated stereotactic radiation therapy (SRS/FSRT) for uveal melanoma.

METHODS AND MATERIALS

We retrospectively evaluated 181 patients with 182 uveal melanomas receiving SRS/FSRT between 2007 and 2013. Treatment was administered with CyberKnife.

RESULTS

According to Collaborative Ocular Melanoma Study criteria, tumor size was small in 1%, medium in 49.5%, and large in 49.5% of the patients. Seventy-one tumors received <45 Gy, and 111 received ≥45 Gy. Median follow-up time was 24 months. Complete and partial response was observed in 8 and 104 eyes, respectively. The rate of 5-year overall survival was 98%, disease-free survival 57%, local recurrence-free survival 73%, distant metastasis-free survival 69%, and enucleation-free survival 73%. There was a significant correlation between tumor size and disease-free survival, SRS/FSRT dose and enucleation-free survival; and both were prognostic for local recurrence-free survival. Enucleation was performed in 41 eyes owing to progression in 26 and complications in 11.

CONCLUSIONS

The radiation therapy dose is of great importance for local control and eye retention; the best treatment outcome was achieved using ≥45 Gy in 3 fractions.

Toxicity profile of intensity-modulated radiation therapy for head and neck carcinoma and potential role of amifostine

Organ function preservation in patients with head and neck cancer can be achieved by intensity-modulated radiation therapy (IMRT). Much of the work on the physics of IMRT has been done for currently available IMRT systems. However, clinical data remain scarce. Before IMRT is accepted as a standard of care, more comprehensive clinical data on the outcomes of IMRT are needed to substantiate its superiority and advantages over conventional modes of radiotherapy. Concomitant chemoradiation and altered fractionation schemes improve local-regional control, but at the cost of increased toxicity. This article presents a 3-year update of the toxicity profile and therapeutic outcomes of 126 patients with head and neck carcinoma treated with IMRT. An ongoing trial of concomitant chemotherapy and IMRT with subcutaneous amifostine (Ethyol, WR-2721; MedImmune, Inc, Gaithersburg, MD) for organ function preservation is also discussed.

Stereotactic body radiotherapy for oligoprogressive lesions in metastatic castration-resistant prostate cancer patients during abiraterone/enzalutamide treatment

BACKGROUND

Metastasis-directed therapy (MDT) utilizing stereotactic body radiotherapy (SBRT) for oligoprogressive lesions could provide a delay in next-line systemic treatment (NEST) change while undergoing androgen receptor-targeted agents (ARTA) treatment. We evaluated prognostic factors for prostate cancer-specific survival (PCSS) and progression-free survival (PFS) to characterize patients receiving treatment with ARTA who may benefit from MDT for oligoprogressive lesions. The impact of MDT on delaying NEST and the predictive factors for NEST-free survival (NEST-FS) were also assessed.

MATERIALS AND METHODS

The clinical data of 54 metastatic castration-resistant prostate cancer patients with 126 oligoprogressive lesions receiving abiraterone (1 g/day) or enzalutamide (160 mg/day) before or after systemic chemotherapy were analyzed. A median of three lesions (range: 1-5) were treated with MDT. The primary endpoints were PCSS and PFS. The secondary endpoints were time to switch to NEST and NEST-FS.

RESULTS

The median follow-up time was 19.1 months. Univariate analysis showed that the number of oligoprogressive lesions treated with SBRT and the time between the start of ARTA treatment and oligoprogression were significant prognostic factors for PCSS, and the timing of ARTA treatment (before or after chemotherapy) and the prostate-specific antigen (PSA) response after MDT were significant prognostic factors for PFS. Multivariate analysis showed that early MDT for oligoprogressive lesions delivered less than 6 months after the beginning of ARTA and higher PSA levels after MDT were significant predictors of worse PCSS and PFS. The median total duration of ARTA treatment was 13.8 months. The median time between the start of ARTA treatment and the start of MDT for oligoprogressive lesions was 5.2 months, and MDT extended the ARTA treatment by 8.6 months on average. Thirty-two (59.3%) patients continued ARTA treatment after MDT. ARTA treatment after chemotherapy, early oligoprogression requiring MDT, and lower radiation doses for MDT were independent predictors of NEST-FS in multivariate analysis.

CONCLUSIONS

MDT for oligoprogressive lesions is effective and may provide several benefits compared to switching from ARTA treatment to NEST. Patients with early progression while on ARTAs and inadequate PSA responses after MDT have a greater risk of rapid disease progression and poor survival, which necessitates intensified treatment.

Clinical experience of head-and-neck cancer IMRT with serial tomotherapy

New radiotherapy planning and delivery techniques are undergoing rapid progress and change due to computer hardware and software technologies that have led to the development of sophisticated 3-dimensional (3D) radiation treatment planning and computer-controlled radiation therapy delivery systems. Intensity-modulated radiation therapy (IMRT) is the most recent and advanced form of external beam radiation therapy often used to perform 3D conformal radiotherapy. It represents one of the most important technical advances in radiotherapy. IMRT has the potential to achieve a much higher degree of target conformity and normal tissue sparing than most other treatment techniques, especially for target volumes at risk with complex shapes and concave regions such as head-and-neck cancer. In this review, we summarize our own IMRT treatment techniques with serial tomotherapy and our clinical experience with 126 patients with head-and-neck IMRT.

Intensity-modulated radiation therapy for head and neck cancer

Intensity-modulated radiation therapy (IMRT) involves the delivery of optimized nonuniform beam intensities to the patient. In the head and neck region, there are many critical structures in close proximity to the target, with little influence from internal organ motion. Because IMRT produces tightly conformal doses and steep-dose gradients next to normal tissues, it provides the potential for organ sparing and improved tumor control. The dosimetric superiority of head and neck IMRT over conventional techniques has been demonstrated. The initial results of clinical IMRT studies showed reduction in xerostomia with no compromise in locoregional control if caution and appropriate knowledge are exercised in target determination and delineation.

Role of 68-Ga-PSMA-PET/CT in pelvic radiotherapy field definitions for lymph node coverage in prostate cancer patients

PURPOSE

To evaluate the distribution of metastatic lymph nodes (LN) detected on 68Ga-PSMA-positron emission tomography/computed tomography (PET/CT) in treatment-naïve prostate cancer (PC) patients and to analyze the LN coverage rates of the pelvic fields defined in the GETUG trial and RTOG guidelines and a pelvic field extending superiorly from the L4/L5 interspace.

MATERIALS AND METHODS

68Ga-PSMA-PET/CT images obtained at diagnosis of 138 PC patients were retrospectively analyzed. The number and locations of 68Ga-PSMA-positive LNs were co-registered with one single-planning CT. The numbers, locations, and sizes of LNs located outside the three pelvic volumes were investigated for the entire cohort and for patients with LN metastasis in the pelvic area only.

RESULTS

A total of 441 PSMA-PET-positive LN metastases were identified. The most frequent metastatic LNs were internal iliac LNs (25.2%). Para-aortic and presacral LNs outside the three pelvic fields were present in 20 (14.5%) and 22 patients (15.9%), respectively. The LN coverage rates according to the GETUG trial, the RTOG guidelines, and the pelvic field extending superiorly from L4/L5 were 44.2%, 52.2%, and 71, respectively, in the entire cohort and 51.7%, 61 and 83.1%, respectively, in patients with only pelvic LN metastasis. The number of metastatic LNs was a predictive factor for LNs located outside the three pelvic fields.

CONCLUSIONS

Extending the cranial margin of the pelvic field from L5/S1 to L4/L5 increases the accuracy of pelvic field irradiation in approximately 20% of patients, highlighting the importance of proximal common iliac irradiation, particularly in patients with multiple LN metastasis.

Integration of 68Ga-PSMA-PET/CT in Radiotherapy Planning for Prostate Cancer Patients

To assess the role of Gallium-labeled-prostate-specific membrane antigen PET/CT (Ga-PSMA-PET/CT) in risk group definition and radiotherapy planning in the initially planned definitive radiotherapy (RT) for prostate cancer patients.

METHODS

The clinical data of 191 prostate cancer patients treated with definitive intensity-modulated RT were retrospectively analyzed. All patients were initially staged with thoracoabdominal CT and bone scintigraphy, and the second staging was performed using Ga-PSMA-PET/CT. Both stages were evaluated for the decision making of RT and any change in RT target volumes.

RESULTS

After staging with Ga-PSMA-PET/CT, 26 patients (13.6%) had risk group changes, 16 patients (8.4%) had an increase in risk group, and 10 patients (5.2%) had a decrease in risk group. Down-staging occurred in 22 patients (11.5%), and upstaging was observed in 30 patients (15.7%). A total of 26 patients (13.6%) had nodal stage changes. After the Ga-PSMA-PET/CT scans, the number of metastatic patient increased to 17 (8.9%), with 4 of them moving from oligo- to polymetastatic disease. An additional irradiation of pelvic lymphatics and metastatic site was performed in 13 patients (6.8%) and 6 patients (3.2%), respectively. The RT was aborted in 4 patients (2.1%) because of parenchymal or distant site metastasis observed in the Ga-PSMA-PET/CT.

CONCLUSIONS

We found that Ga-PSMA-PET/CT causes considerable migration in stage, risk group, and RT field arrangements, especially in high-risk patients regardless of the GS and baseline prostate-specific antigen values alone. Ga-PSMA-PET/CT seems to have a great influence on RT decision making in prostate cancer patients.

The dosimetric impact of implants on the spinal cord dose during stereotactic body radiotherapy

BACKGROUND

The effects of spinal implants on dose distribution have been studied for conformal treatment plans. However, the dosimetric impact of spinal implants in stereotactic body radiotherapy (SBRT) treatments has not been studied in spatial orientation. In this study we evaluated the effect of spinal implants placed in sawbone vertebra models implanted as in vivo instrumentations.

METHODS

Four different spinal implant reconstruction techniques were performed using the standard sawbone lumbar vertebrae model; 1. L2-L4 posterior instrumentation without anterior column reconstruction (PI); 2. L2-L4 anterior instrumentation, L3 corpectomy, and anterior column reconstruction with a titanium cage (AIAC); 3. L2-L4 posterior instrumentation, L3 corpectomy, and anterior column reconstruction with a titanium cage (PIAC); 4. L2-L4 anterior instrumentation, L3 corpectomy, and anterior column reconstruction with chest tubes filled with bone cement (AIABc). The target was defined as the spinous process and lamina of the lumbar (L) 3 vertebra. A thermoluminescent dosimeter (TLD, LiF:Mg,Ti) was located on the measurement point anterior to the spinal cord. The prescription dose was 8 Gy and the treatment was administered in a single fraction using a CyberKnife® (Accuray Inc., Sunnyvale, CA, USA). We performed two different treatment plans. In Plan A beam interaction with the rod was not limited. In plan B the rod was considered a structure of avoidance, and interaction between the rod and beam was prevented. TLD measurements were compared with the point dose calculated by the treatment planning system (TPS).

RESULTS AND DISCUSSION

In plan A, the difference between TLD measurement and the dose calculated by the TPS was 1.7 %, 2.8 %, and 2.7 % for the sawbone with no implant, PI, and PIAC models, respectively. For the AIAC model the TLD dose was 13.8 % higher than the TPS dose; the difference was 18.6 % for the AIABc model. In plan B for the AIAC and AIABc models, TLD measurement was 2.5 % and 0.9 % higher than the dose calculated by the TPS, respectively.

CONCLUSIONS

Spinal implants may be present in the treatment field in patients scheduled to undergo SBRT. For the types of implants studied herein anterior rod instrumentation resulted in an increase in the spinal cord dose, whereas use of a titanium cage had a minimal effect on dose distribution. While planning SBRT in patients with spinal reconstructions, avoidance of the rod and preventing interaction between the rod and beam might be the optimal solution for preventing unexpectedly high spinal cord doses.

Oligometastatic Bone Disease in Castration-Sensitive Prostate Cancer Patients Treated With Stereotactic Body Radiotherapy Using 68Ga-PSMA PET/CT: TROD 09-004 Study

PURPOSE

To evaluate the outcomes of metastasis-directed treatment (MDT) using stereotactic body radiotherapy (SBRT) for bone-only oligometastasis (OM) detected with gallium prostate-specific membrane antigen (68Ga-PSMA) PET/CT in castration-sensitive prostate cancer (PC) patients.

METHODS

In this multi-institutional study, clinical data of 74 PC patients with 153 bone lesions who were undergoing MDT were retrospectively evaluated. Twenty-seven patients (36.5%) had synchronous, and 47 (63.5%) had metachronous OM. All patients had PC with 5 metastases or fewer detected by 68Ga-PSMA PET/CT and treated using SBRT with a median dose of 20 Gy. The prognostic factors for PC-specific survival (PCSS) and progression-free survival (PFS) were analyzed.

RESULTS

The median follow-up was 27.3 months. Patients with synchronous OM were older and received higher rates of androgen deprivation therapy after SBRT compared with patients with metachronous OM. The 2-year PCSS and PFS rates were 92.0% and 72.0%, respectively. A prostate-specific antigen (PSA) decline was observed in 56 patients (75.7%), and 48 (64.9%) had a PSA response defined as at least 25% decrease of PSA after MDT. The 2-year local control rate per lesion was 95.4%. In multivariate analysis, single OM and PSA response after MDT were significant predictors for better PCSS and PFS. In-field recurrence was observed in 4 patients (6.5%) with 10 lesions at a median of 13.1 months after MDT completion. No serious late toxicity was observed.

CONCLUSIONS

We demonstrated that SBRT is an efficient and well-tolerated treatment option for PC patients with 5 bone-only oligometastases or fewer detected with 68Ga-PSMA PET/CT.