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.

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.

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.

Robotic stereotactic body radiotherapy in the treatment of sinonasal mucosal melanoma: report of four cases

BACKGROUND

Sinonasal mucosal melanoma (SNMM) is a rare entity originating from melanocytes of the sinonasal mucosa. Postoperative radiotherapy is recommended in all cases to increase local control. However, external radiotherapy is rarely used as a definitive treatment modality. In this report, we present 4 cases of SNMM treated with CyberKnife (Accuray, Sunnyvale, CA).

METHODS

All patients were immobilized with a thermoplastic mask. A planning CT scan with 1-mm thickness was obtained, and these images were fused with MRI for the contouring procedure. Multiplan (Accuray) inverse planning software was used for treatment planning. Robotic stereotactic body radiotherapy (SBRT) was delivered with CyberKnife.

RESULTS

Median follow-up was 26 months. Three patients had complete response to CyberKnife, and 1 patient had partial response.

CONCLUSION

Robotic SBRT seems to be an appealing treatment option for local control. Effective systemic treatment is required to prevent distant metastases.

Postoperative radiotherapy and chemotherapy in the management of oligodendroglioma: single institutional review of 88 patients

We retrospectively evaluate the prognostic factors affecting the local control, survival and the potential role of chemotherapy in the management of patients with oligodendroglioma. The medical records of 88 patients treated by postoperative external beam radiotherapy +/- chemotherapy at our institution between December 1993 and December 2002 were analyzed. Nine patients (10%) were treated with an accelerated fractionation scheme, while 79 patients were treated with conventional doses. The median RT dose was 54.8 +/- 2.58 Gy for low-grade tumors, and 58.7 +/- 2.46 Gy for high-grade tumors. PCV chemotherapy regimen was given to 18 patients; temozolamide was administered in three patients. Chemotherapy was not given concomitantly in any patients. The median follow-up was 56 months (range 7-134 months). The 5-year overall and progression-free survival rates for entire group were 86% and 79%, respectively. Patients with epilepsy at presentation had better 5-year overall survival (93% vs. 74%, P=0.04). High grade tumors had significantly lower overall survival rate. Age, presence of motor deficit at diagnosis and histological grade were found have a significant impact on progression-free survival. The 5-year overall and progression free survival rates of patients with high-grade tumors were 69%, 51% and 74%, 68% for chemotherapy and no-chemotherapy group, respectively (P=0.9 for OS, P=0.3 for PFS). In multivariate analysis no significant factor affecting the overall survival and progression-free survival was found. Chemotherapy given after postoperative radiotherapy in patients with oligodendroglioma did not improve survival in this retrospective study.

Current role of modern radiotherapy techniques in the management of breast cancer

Breast cancer is the most common type of malignancy in females. Advances in systemic therapies and radiotherapy (RT) provided long survival rates in breast cancer patients. RT has a major role in the management of breast cancer. During the past 15 years several developments took place in the field of imaging and irradiation techniques, intensity modulated RT, hypofractionation and partial-breast irradiation. Currently, improvements in the RT technology allow us a subsequent decrease in the treatment-related complications such as fibrosis and long-term cardiac toxicity while improving the loco-regional control rates and cosmetic results. Thus, it is crucial that modern radiotherapy techniques should be carried out with maximum care and efficiency. Several randomized trials provided evidence for the feasibility of modern radiotherapy techniques in the management of breast cancer. However, the role of modern radiotherapy techniques in the management of breast cancer will continue to be defined by the mature results of randomized trials. Current review will provide an up-to-date evidence based data on the role of modern radiotherapy techniques in the management of breast cancer.

Treatment outcomes of prostate cancer patients with Gleason score 8-10 treated with definitive radiotherapy : TROD 09-001 multi-institutional study

PURPOSE

To validate the clinical outcomes and prognostic factors in prostate cancer (PCa) patients with Gleason score (GS) 8-10 disease treated with external beam radiotherapy (EBRT) + androgen deprivation therapy (ADT) in the modern era.

METHODS

Institutional databases of biopsy proven 641 patients with GS 8-10 PCa treated between 2000 and 2015 were collected from 11 institutions. In this multi-institutional Turkish Radiation Oncology Group study, a standard database sheet was sent to each institution for patient enrollment. The inclusion criteria were, T1-T3N0M0 disease according to AJCC (American Joint Committee on Cancer) 2010 Staging System, no prior diagnosis of malignancy, at least 70 Gy total irradiation dose to prostate ± seminal vesicles delivered with either three-dimensional conformal RT or intensity-modulated RT and patients receiving ADT.

RESULTS

The median follow-up time was 5.9 years (range 0.4-18.2 years); 5‑year overall survival (OS), biochemical relapse-free survival (BRFS) and distant metastases-free survival (DMFS) rates were 88%, 78%, and 79%, respectively. Higher RT doses (≥78 Gy) and longer ADT duration (≥2 years) were significant predictors for improved DMFS, whereas advanced stage was a negative prognosticator for DMFS in patients with GS 9-10.

CONCLUSIONS

Our results validated the fact that oncologic outcomes after radical EBRT significantly differ in men with GS 8 versus those with GS 9-10 prostate cancer. We found that EBRT dose was important predictive factor regardless of ADT period. Patients receiving 'non-optimal treatment' (RT doses <78 Gy and ADT period <2 years) had the worst treatment outcomes.

Prognostic significance of castrate testosterone levels for patients with intermediate and high risk prostate cancer

BACKGROUND

Testosterone level of < 50 ng/dL has been used to define castrate level after surgery or after androgen deprivation treatment (ADT) in metastatic prostate cancer (PC).

AIM

To evaluate the effect of two different castrate testosterone levels, < 50 and < 20 ng/dL, on biochemical relapse free survival (BRFS) in patients with non-metastatic intermediate and high risk PC receiving definitive radiotherapy (RT) and ADT.

METHODS

Between April 1998 and February 2011; 173 patients with intermediate and high risk disease were treated. Radiotherapy was delivered by either three-dimensional-conformal technique to a total dose of 73.4 Gy at the ICRU reference point or intensity modulated radiotherapy technique to a total dose of 76 Gy. All the patients received 3 mo of neoadjuvant ADT followed by RT and additional 6 mo of ADT. ASTRO Phoenix definition was used to define biochemical relapse.

RESULTS

Median follow up duration was 125 months. Ninety-six patients (56%) had castrate testosterone level < 20 ng/dL and 139 patients (80%) had castrate testosterone level < 50 ng/dL. Both values are valid at predicting BRFS. However, patients with testosterone < 20 ng/dL have significantly better BRFS compared to other groups (P = 0.003). When we compare two values, it was found that using 20 ng/dL is better than 50 ng/dL in predicting the BRFS (AUC = 0.63 vs 0.58, respectively).

CONCLUSION

Castrate testosterone level of less than 20 ng/dL is associated with better BRFS and is better in predicting the BRFS. Further studies using current standard of care of high dose IMRT and longer ADT duration might support these findings.

Robotic stereotactic radiosurgery in patients with nasal cavity and paranasal sinus tumors

The aim of this retrospective study is to evaluate our therapeutic results in patients with paranasal sinus (PNS) or nasal cavity (NC) malignancies treated with robotic stereotactic radiosurgery (SRS). Between August 2007 and October 2008, 27 patients with PNS or NC tumors were treated in our department using SRS. Median age was 53 years (range, 27-84 years). Eleven patients were female and sixteen were male. Most common histopathology was SCC (44%). The disease involved the maxillary sinus in 15 patients (55%). SRS was applied to 6 patients (22%) for reirradiation, while the others received it as a primary treatment. Seven patients had SRS as a boost dose to external beam radiotherapy. SRS was delivered with cyberknife (Accuray Incorporated, Sunnyvale, CA, USA). The median dose to the tumor was 31 Gy (range, 15-37.5 Gy) in median 5 fractions (range, 3-5 fractions). After a median follow-up of 21.4 months (range, 3-59 months), 76% of the patients were free of local relapse. Three patients showed local progression and 3 developed distant metastases. One- and two-year survival rates for the entire group were 95.2% (SEM = 0.046) and 77.1% (SEM = 0.102), respectively. We observed brain necrosis in 2 patients, visual disorder in 2 patients, bone necrosis in 2 patients and trismus in 1 patient as a SRS related late toxicity. Robotic SRS seems to be a feasible treatment strategy for patients with PNS tumors. Further prospective studies with longer follow up times should be performed.

Hyaluronic acid spacer in focal prostate reirradiation: A single centre experience

PURPOSE

The optimal management of locally recurrent prostate cancer after curative radiotherapy is still unknown. In this study, we evaluated the preliminary results of reirradiation using stereotactic body radiotherapy for locally recurrent prostate cancer after initial definitive local radiotherapy.

MATERIALS AND METHODS

Between April 2016 and February 2019, 11 patients with recurrent disease at the previously irradiated prostate were treated. Local recurrence was detected by radiological with or without functional imaging modalities including prostate multiparametric/pelvic MRI or positron-emission tomography-computerised tomography with (68Ga)-labelled prostate-specific membrane antigen performed after rising prostate specific antigen serum level during follow-up. All patients received stereotactic body radiotherapy to the recurrent nodule to a total dose of 30Gy in five fractions. Hyaluronic acid spacer was injected between prostate and rectum in seven patients to decrease the rectal dose. Acute toxicity was evaluated by using Common Terminology Criteria for Adverse Events version 4.0, and late toxicity was evaluated by using Radiation Therapy Oncology Group/European Organisation for Research and Treatment of Cancer late radiation morbidity scoring schema.

RESULTS

At the diagnosis, the median age was 64 years, and the mean prostate specific antigen serum concentration was 17.7ng/mL. The median interval time between local recurrence and initial definitive radiotherapy was 63 months. Mean prostate specific antigen concentration nadir value during follow-up was 0.43ng/mL. With a median follow up of 19 months, three patients developed either local or distant relapse. One patient had grade 3 acute rectal toxicity, and one patient had grade 2 late urinary toxicity. We did not observe any acute or late toxicity due to hyaluronic acid spacer injection.

CONCLUSION

Reirradiation after local recurrence following initial definitive radiotherapy together with hyaluronic acid spacer use seems to be effective and safe.

Treatment outcomes of postoperative ultra-hypofractionated stereotactic body radiotherapy in prostate cancer

BACKGROUND

This study aimed to evaluate the safety and efficacy of ultra-hypofractionated stereotactic body radiation therapy (SBRT) to prostate bed.

METHODS

Sixty-six prostate cancer patients treated with postoperative ultra-hypofractionated SBRT between 2018 and 2020 were retrospectively reviewed. All patients received a total dose of 35 Gy to prostate bed in 5 fractions. Biochemical complete response (BCR), biochemical failure (BF), acute and late toxicities were assessed.

RESULTS

After a median follow-up of 24.2 months (range, 6.4-37.2), seven patients (10.6%) developed BF, and the 2-year freedom from BF (FFBF) rate was 88.4%. BCR was observed in 57 patients (86.4%). The 2-year FFBF in patients with pre-SBRT PSA value of <0.2 ng/mL was higher than those with pre-SBRT PSA of ≥0.2 ng/mL (100% vs. 81.4%; P = 0.04). The 2-year FFBF in patients with BCR was significantly higher than in those without BCR (94.5% vs. 58.3%; P < 0.001). In multivariate analysis, pre-SBRT PSA and post-SBRT PSA values were prognostic factors for FFBF (P = 0.009 and P = 0.01, respectively). Nine patients (13.6 %) developed acute and late grade 2 genitourinary (GU) toxicities. There was no acute or late grade ≥3 GU toxicity. Acute and late grade ≥2 gastrointestinal (GI) toxicity was observed in 9 (13.6%) and 2 (3%) patients, respectively.

CONCLUSION

Postoperative ultra-fractionated SBRT showed no severe acute toxicity and late toxicity rates of about 15%, in addition to excellent biochemical control rates. Pre- and post-SBRT PSA levels may be a predictor of BCR in patients receiving post-operative ultra-fractionated SBRT.

The effect of incidental dose to pelvic nodes in bladder-only irradiation in the era of IMRT: a dosimetric study

PURPOSE

While three-dimensional radiotherapy (RT) causes high incidental nodal doses in bladder-only irradiation for muscle-invasive bladder cancer (MIBC), the impact on pelvic lymphatics is unclear in the era of intensity-modulated RT (IMRT). This study evaluates incidental doses to pelvic lymphatics in MIBC patients treated with IMRT.

METHODS

The data of 40 MIBC patients treated with bladder-only IMRT and concurrent chemotherapy were retrospectively evaluated. The pelvic lymphatics were contoured on initial simulation images and incidental nodal doses were evaluated. The Statistical Package for the Social Sciences (SPSS) version 23.0 (IBM, Armonk, NY, USA) was used for statistics.

RESULTS

Median RT dose to the bladder was 60 Gy in 30 fractions. In dosimetric analysis, median values of mean dose (Dmean) of the obturator, presacral, external iliac, internal iliac, and distal common iliac lymphatics were 33 Gy (range 4-50 Gy), 3 Gy (range 1-28 Gy), 9.5 Gy (range 3-41 Gy), 7.5 Gy (range 2-14 Gy), and 1 Gy (range 0-15 Gy), respectively. The Dmean of the obturator lymphatics was significantly higher (p < 0.001) and the Dmean of the distal common iliac lymphatics was significantly lower (p < 0.001) than all remaining lymphatic stations. The Dmean of the external iliac lymphatics was significantly higher than that of the presacral lymphatics (p < 0.001), but the difference with the internal iliac lymphatics was not statistically significant (p = 0.563).

CONCLUSION

The incidental nodal doses with bladder-only IMRT are heterogeneous and remain below the generally accepted doses for microscopic disease eradication for bladder cancer.

Testicular metastasis in prostate cancer: A rare case of testicular metastasis diagnosed with 68Ga-PSMA and review of the literature

Objective:

Testicular metastasis in prostate cancer is a rare entity. We aimed to report the case where this rare condition was diagnosed with Gallium prostate-specific membrane antigen–positron emission tomography/computed tomography (68Ga-PSMA-PET/CT).

Subjects/patients and methods:

A 68-year-old male with a prostate adenocarcinoma presented with testicular metastasis. The patient was diagnosed with 68Ga-PSMA-PET/CT, and bilateral inguinal orchiectomy was performed. Herein, our case is presented, and a short review of the literature is carried out.

Conclusion:

68Ga-PSMA-PET/CT is an effective imaging method for detecting rare metastases.

Level of evidence:

4

Predicting acute and late toxicity in prostate cancer stereotactic ablative radiotherapy: the role of dosimetric parameters and prostate volume

PURPOSE

Our objective was to identify the dosimetric parameters and prostate volume that most accurately predict the incidence of acute and late gastrointestinal (GI) and genitourinary (GU) toxicity in prostate cancer stereotactic ablative radiotherapy (SABR) treatments.

METHODS

We conducted a retrospective analysis of 122 patients who received SABR for prostate cancer at our clinic between March 2018 and September 2022 using a five-fraction SABR regimen. The existing plans of these patients were re-evaluated according to our institutional protocols (Hacettepe University [HU-1] and HU-2) as well as PACE‑B, RTOG 0938, and NRG GU005 dose-volume constraints. Univariate and multivariate logistic regression analyses were performed using SPSS version 23.0 (IBM, Armonk, NY, USA).

RESULTS

The median follow-up was 24.7 months (0.8-94.4 months). For acute GU toxicity, moderate-dose regions were predictive for grade 1-2 toxicity, while high-dose regions were more associated with grade 3-4 toxicity. For late GU toxicity, moderate-high-dose regions were predictive. For GI toxicity, moderate-dose regions were important for both acute and late toxicity. The HU protocol encompassed all significant dosimetric factors influencing toxicity outcomes. A prostate volume threshold of 60 cc was predictive of acute grade 3-4 GU toxicity.

CONCLUSION

Our study highlighted the critical role of moderate-dose regions for acute and late GI and GU toxicity. Prostate treatment plans should be rigorously evaluated, and moderate doses should be minimized. The HU protocol is an eligible choice for five-fraction SABR plans.

Robotic stereotactic radiosurgery in patients with nasal cavity and paranasal sinus tumors

The aim of this retrospective study is to evaluate our therapeutic results in patients with paranasal sinus (PNS) or nasal cavity (NC) malignancies treated with robotic stereotactic radiosurgery (SRS). Between August 2007 and October 2008, 27 patients with PNS or NC tumors were treated in our department using SRS. Median age was 53 years (range, 27-84 years). Eleven patients were female and sixteen were male. Most common histopathology was SCC (44%). The disease involved the maxillary sinus in 15 patients (55%). SRS was applied to 6 patients (22%) for reirradiation, while the others received it as a primary treatment. Seven patients had SRS as a boost dose to external beam radiotherapy. SRS was delivered with cyberknife (Accuray Incorporated, Sunnyvale, CA, USA). The median dose to the tumor was 31 Gy (range, 15-37.5 Gy) in median 5 fractions (range, 3-5 fractions). After a median follow-up of 21.4 months (range, 3-59 months), 76% of the patients were free of local relapse. Three patients showed local progression and 3 developed distant metastases. One- and two-year survival rates for the entire group were 95.2% (SEM = 0.046) and 77.1% (SEM = 0.102), respectively. We observed brain necrosis in 2 patients, visual disorder in 2 patients, bone necrosis in 2 patients and trismus in 1 patient as a SRS related late toxicity. Robotic SRS seems to be a feasible treatment strategy for patients with PNS tumors. Further prospective studies with longer follow up times should be performed.