The impact of margin reduction on radiation dose distribution of ultra-hypofractionated prostate radiotherapy utilizing a 1.5-T MR-Linac.

BACKGROUND: We examined the effects of reducing the planning target volume (PTV) margin in MR-guided radiotherapy (MRgRT) on the distribution of radiation dose to target volumes and organs-at-risk (OARs). Thus, we compared MR-Linac (MRL) plans with and without reduced margin and intensity-modulated radiotherapy (IMRT) plan with conventional linac for low-risk prostate cancer patients receiving 36.25 Gy in five fractions of ultra-hypofractionated radiation therapy. MATERIALS AND METHODS: Twenty low-risk prostate cancer patients treated with 1.5 T MR-Linac were evaluated. The same planning CT images were used for four plans: the MRL-R plan with reduced margin planning target volume (PTV-R) and the MRL-N plan with normal margin PTV (PTV-N), which is also used for IMRT plan. In four plans, PTV doses, organs-at-risk (OARs) doses, the homogeneity index (HI), and monitor units were compared. RESULTS: All plans met the criteria for PTV coverage and OARs dose constraints. The maximum and mean PTV doses were significantly higher in the MRL-R and MRL-N plans compared to the IMRT plan. The HI was lowest in the IMRT plan (0.040 ± 0.013) and highest in the MRL-N plan (0.055 ± 0.012; p < 0.001). There was no significant difference in the PTV dosimetric parameters between the MRL-R and the MRL-N plans. The high doses in the rectum was significantly lower in the MRL-R compared to other plans. The bladder V36.25 Gy was significantly lower in the MRL-R plan (2.43 ± 1.87 Gy) compared to MRL-N (4.50 ± 2.42 Gy; p < 0.001), and IMRT plans (4.76 ± 2.77 Gy; p < 0.001). There was no significant difference in the low-dose volumes of the body, maximum femur doses, or monitor units across each plan. CONCLUSIONS: Ultra-hypofractionated MR-guided RT with 1.5 T MRL is dosimetrically feasible for patients with prostate cancer. The improved soft tissue contrast and the online adaptive plan for 1.5 T MR-Linac allows for PTV margin reduction resulted in a significant dose reduction in OARs.

Treatment outcomes of simultaneous integrated boost to intraprostatic lesions with external beam radiotherapy in localized prostate cancer patients.

BACKGROUND: To evaluate the treatment outcomes and toxicity of definitive radiotherapy (RT) for prostate cancer (PC) patients using the simultaneous integrated boost (SIB) technique, which delivered 78 Gy to the entire prostate and 86 Gy to the intraprostatic lesion (IPL) in 39 fractions. MATERIALS AND METHODS: Univariable and multivariable analyses were conducted of the prognostic factors for freedom from biochemical failure (FFBF), progression-free survival (PFS), and PC-specific survival (PCSS) of 619 PC patients who received definitive RT between September 2012 and August 2021. Predictors of late Grade ≥2 genitourinary (GU) and gastrointestinal (GI) toxicities were also identified using logistic regression. RESULTS: The median follow-up for entire cohort was 68.5 months. The 5-year FFBF, PFS, and PCSS rates were 93.2%, 83.2%, and 98.6%, respectively. They were predicted by the serum prostate-specific antigen, Gleason score (GS), clinical nodal stage, and D'Amico risk group. Only 45 patients (7.3%) developed disease recurrence 41.9 months after RT. The 5-year FFBF rates for low-, intermediate-, and high-risk disease were 98.0%, 93.1%, and 88.5%, respectively (p < 0.001). The 5-year PFS and PCSS rates according to risk groups were 91.0%, 82.1%, and 77.4% (p < 0.001), and 99.2%, 96.4%, and 95.9% (p = 0.03), and, respectively. GS > 7 and lymph node metastasis negatively predicted FFBF and PCSS in multivariable analysis. Ninety (14.6%) and 44 (7.1%) patients had acute Grade ≥2 GU and GI toxicities, respectively, and 42 (6.8%) and 27 (4.4%) patients had late Grade ≥2 GU and GI toxicities, respectively. Diabetes and transurethral resection independently predicted late Grade 2 GU toxicity, but no significant predictor of late Grade ≥2 GI toxicity was found. CONCLUSIONS: Localized PC was effectively and safely treated with definitive RT using the SIB technique to deliver 86 Gy to the IPL in 39 fractions without severe late toxicity. This finding must be validated with long-term results.

Treatment Outcomes of Stereotactic Body Radiotherapy in Patients with Synchronous and Metachronous Oligometastatic Renal Cell Carcinoma.

INTRODUCTION: The aim of this study was to investigate the clinical outcomes of metastasis-directed therapy (MDT) using stereotactic body radiotherapy (SBRT) in patients with synchronous or metachronous oligometastatic renal cell carcinoma (RCC). METHODS: The clinical data of 87 patients with 138 lesions who received MDT between February 2008 and January 2019 were retrospectively analyzed. All patients had ≤5 metastasis at diagnosis (synchronous) or during progression (metachronous) and were treated with SBRT for their metastasis. The primary endpoints were local control (LC) and progression-free survival (PFS). The secondary endpoint was overall survival (OS). RESULTS: Median follow-up was 20.4 months for entire cohort and 27.2 months for survivors. Synchronous oligometastatic disease was observed in 35 patients (40.2%), and 52 patients (59.8%) had metachronous disease. Seventy-two patients (82.8%) received systemic treatment synchronously or after MDT, while 15 patients (17.2%) did not receive any systemic treatment. The 1- and 2-year OS rates were 79.4% and 58.1%, respectively, and the 1- and 2-year PFS rates were 58.6% and 15.1%, respectively. The 1- and 2-year LC rates per lesion were 96.6% and 91.4%, respectively. There were no significant differences in survival between patients with synchronous oligometastasis and those with metachronous oligometastasis. All disease progressions were observed at a median time of 31.6 months (range: 1.9-196.9 months) after the completion of SBRT. Patients with solitary oligometastasis had significantly better OS compared to patients with >1 metastasis (p = 0.04). No patients experienced grade 3 or higher acute or late toxicities. CONCLUSION: SBRT is a successful treatment for oligometastatic RCC patients due to its excellent LC and minimal toxicity profile. There were no statistically significant survival differences between patients with synchronous and metachronous oligometastasis. Patients with solitary oligometastasis outlived their counterparts.

Stereotactic body radiotherapy and tyrosine kinase inhibitors in patients with oligometastatic renal cell carcinoma: a multi-institutional study.

PURPOSE: Few studies have determined the viability of stereotactic body radiotherapy (SBRT) and tyrosine kinase inhibitors (TKIs) in the treatment of metastatic renal cell carcinoma (mRCC). We examined the results of RCC patients who had five or fewer lesions and were treated with TKI and SBRT. METHODS: The clinical data of 42 patients with 96 metastases treated between 2011 and 2020 were retrospectively evaluated. The prognostic factors predicting overall survival (OS) and progression-free survival (PFS) were assessed in uni- and multivariable analyses. RESULTS: Median follow-up and time between TKI therapy and SBRT were 62.3 and 3.7 months, respectively. The 2­year OS and PFS rates were 58.0% and 51.3%, respectively, and 2­year local control rate was 94.1% per SBRT-treated lesion. In univariable analysis, the time between TKI therapy and SBRT and treatment response were significant prognostic factors for OS and PFS. In multivariable analysis, a time between TKI therapy and SBRT of less than 3 months and complete response were significant predictors of better OS and PFS. Only 12 patients (28.6%) had a systemic treatment change at a median of 18.2 months after SBRT, mostly in patients with a non-complete treatment response after this therapy. Two patients (4.8%) experienced grade III toxicity, and all side effects observed during metastasis-directed therapy subsided over time. CONCLUSION: We demonstrated that SBRT in combination with TKIs is an effective and safe treatment option for RCC patients with ≤ 5 metastases. However, distant metastasis was observed in 60% of the patients, indicating that distant disease control still has room for improvement.

The utility of 1.5 tesla MR-guided adaptive stereotactic body radiotherapy for recurrent ovarian tumor - Case reports and review of the literature.

INTRODUCTION: Although epithelioid ovarian cancer (EOC) is a radiosensitive tumor and radiotherapy (RT) played a significant role in adjuvant treatment management in the past, the role of RT has evolved with the advent of platinum-based chemotherapy regimens. Nonetheless, modern RT techniques may be useful in certain patients particularly those with recurrent disease. PRESENTATION OF CASE: After surgery and chemotherapy, two patients, aged 57 and 70, presented with recurrent lesions in the parailiac region. The recurrent lesions were treated with high field 1.5-Tesla MR-Linac treatment in 5 fractions at a dose of 30 Gy. The patients tolerated the treatment well and were disease free after 12 and 20 months of magnetic resonance guided radiotherapy (MRgRT), respectively. DISCUSSION: MRgRT is a novel and rapidly evolving technology that allows for the highly precise treatment of even mobile targets through direct visualization of the tumor. The majority of patients with EOC frequently present with abdominal-pelvic recurrences. It has been demonstrated that EOC requires high radiation doses for curative treatment. MR-Linac enables monitoring of organ motion during treatment, which is necessary for delivering higher doses to target volumes while sparing surrounding organs. CONCLUSION: To reduce radiation doses to nearby normal tissues, MRgRT allows for the delivery of hypofractionated RT with tight safety margins. Regardless of initial resistance or gradual development of intolerance to standard chemotherapy regimens, the role of RT in patients with persistent or recurrent EOC should be reconsidered.

Cardiac angiosarcoma treated with 1.5 Tesla MR-guided adaptive stereotactic body radiotherapy - Case report and review of the literature.

INTRODUCTION: Cardiac angiosarcoma is a very rare disease. As a result of their nonspecific presentation symptoms, and the lack of consensus in treatment, caution should be taken in both diagnosis and treatment. The role of radiotherapy (RT) is debatable due to the continuous movement of the heart, which makes it difficult to safely deliver high radiation doses to the target volume. PRESENTATION OF CASE: The case of a 16-year-old boy with cardiac angiosarcoma that recurred one year after surgery and was treated with chemotherapy is presented. The patient received high field 1.5-Tesla (magnetic resonance) MR-Linac treatment in 5 fractions with a dosage of 25 Gy to the tumor bed and 30 Gy to the recurrent nodules using the simultaneous integrated boost technique. The patient tolerated the treatment well and had stable disease two months later. DISCUSSION: MR-guided radiotherapy, particularly in the case of cardiac malignancies, allows for direct tumor visualization with high soft tissue image resolution capacity. Furthermore, modern RT techniques allow for the full therapeutic window to be used by achieving superior dose distributions, allowing for dose escalation strategies with tolerable toxicity rates. CONCLUSION: Magnetic resonance guided RT allows direct visualization of the target during treatment delivery, allowing for higher-dose administration with less damage to healthy tissue near the tumor. This treatment strategy is a viable option in selected patients with cardiac angiosarcoma.

The role of stereotactic body radiotherapy in switching systemic therapy for patients with extracranial oligometastatic renal cell carcinoma

BackgroundTargeting oligometastatic lesions with metastasis-directed therapy (MDT) using stereotactic-body radiotherapy (SBRT) may improve treatment outcomes and postpone the need for second-line systemic therapy (NEST). We looked at the results of oligometastatic renal cell carcinoma (RCC) patients who had five or fewer lesions and were treated with SBRT.MethodsWe examined the treatment outcomes of 70 extracranial metastatic RCC (mRCC) patients treated at two oncology centers between 2011 and 2020. The clinical parameters of patients with and without NEST changes were compared. The prognostic factors for overall survival (OS), progression-free survival (PFS), and NEST-free survival were evaluated.ResultsMedian age was 67 years (range 31–83 years). Lung and bone metastasis were found in 78.4% and 12.6% of patients, respectively. With a median follow-up of 21.1 months, median OS was 49.1 months and the median PFS was 18.3 months. Histology was a prognostic factor for OS, BED, and treatment switch for PFS in univariate analysis. In multivariate analysis, the significant predictor of poor OS was clear cell histology, and a lower BED for PFS. Following SBRT for oligometastatic lesions, 19 patients (27.2%) had a median NEST change of 15.2 months after MDT completion. There were no significant differences in median OS or PFS between patients who had NEST changes and those who did not. No patient experienced grade ≥ 3 acute and late toxicities.ConclusionsThe SBRT to oligometastatic sites is an effective and safe treatment option for ≤ 5 metastases in RCC patients by providing favorable survival and delaying NEST change. (AU)

Bone-only oligometastatic renal cell carcinoma patients treated with stereotactic body radiotherapy: a multi-institutional study.

PURPOSE: This study aimed to analyze the prognostic factors associated with overall survival (OS) and progression-free survival (PFS) in patients with bone-only metastatic renal cell carcinoma (RCC) who have five or fewer lesions treated with stereotactic body radiotherapy (SBRT). METHODS: The clinical data of 54 patients with 70 bone metastases undergoing SBRT treated between 2013 and 2020 with a dose of at least 5 Gy per fraction and a biologically effective dose (BED) of at least 90 Gy were retrospectively evaluated. RESULTS: The majority of lesions were located in the spine (57.4%) and had only one metastasis (64.8%). After a median follow-up of 22.4 months, the 1­ and 2­year OS rates were 84.6% and 67.3%, respectively, and median OS was 43.1 months. The 1­ and 2­year PFS rates and median PFS were 63.0%, 38.9%, and 15.3 months, respectively. In SBRT-treated lesions, the 1­year local control (LC) rate was 94.9%. Age, metastasis localization, and number of fractions of SBRT were significant prognostic factors for OS in univariate analysis. In multivariate analysis, patients with spinal metastasis had better OS compared to their counterparts, and patients who received single-fraction SBRT had better PFS than those who did not. No patient experienced acute or late toxicities of grade 3 or greater. CONCLUSION: Despite excellent LC at the oligometastatic site treated with SBRT, disease progression was observed in nearly half of patients 13 months after metastasis-directed local therapy, particularly as distant disease progression other than the treated lesion, necessitating an effective systemic treatment to improve treatment outcomes.

The role of stereotactic body radiotherapy in switching systemic therapy for patients with extracranial oligometastatic renal cell carcinoma.

BACKGROUND: Targeting oligometastatic lesions with metastasis-directed therapy (MDT) using stereotactic-body radiotherapy (SBRT) may improve treatment outcomes and postpone the need for second-line systemic therapy (NEST). We looked at the results of oligometastatic renal cell carcinoma (RCC) patients who had five or fewer lesions and were treated with SBRT. METHODS: We examined the treatment outcomes of 70 extracranial metastatic RCC (mRCC) patients treated at two oncology centers between 2011 and 2020. The clinical parameters of patients with and without NEST changes were compared. The prognostic factors for overall survival (OS), progression-free survival (PFS), and NEST-free survival were evaluated. RESULTS: Median age was 67 years (range 31-83 years). Lung and bone metastasis were found in 78.4% and 12.6% of patients, respectively. With a median follow-up of 21.1 months, median OS was 49.1 months and the median PFS was 18.3 months. Histology was a prognostic factor for OS, BED, and treatment switch for PFS in univariate analysis. In multivariate analysis, the significant predictor of poor OS was clear cell histology, and a lower BED for PFS. Following SBRT for oligometastatic lesions, 19 patients (27.2%) had a median NEST change of 15.2 months after MDT completion. There were no significant differences in median OS or PFS between patients who had NEST changes and those who did not. No patient experienced grade ≥ 3 acute and late toxicities. CONCLUSIONS: The SBRT to oligometastatic sites is an effective and safe treatment option for ≤ 5 metastases in RCC patients by providing favorable survival and delaying NEST change.

Comment on Hunt et al, "Feasibility of magnetic resonance guided radiotherapy for the treatment of bladder cancer".

•Bladder cancer patients who are unsuitable for standard radical treatments present a large unfulfilled clinical need.•Hypofractionated RT can be an appropriate solution for these patients; however organ movement and changes in bladder filling is important obstacle for such treatment strategies.•The only way to overcome this obstacle is that using online adaptive image-guided RT.•There is need of new studies evaluating the role of MRgRT for bladder cancer patients.

Aggressive treatment for urothelial cancer-complete urinary tract extirpation: Operative feasibility in two cases.

Bladder cancer (BC), the most common malignancy of the urinary tract, accounts for 90-95% of all urothelial carcinomas (UCs), while upper urinary tract UC (UUTUC) accounts for only 5-10%. Radical nephroureterectomy with excision of bladder cuff, and radical cystectomy with pelvic lymph node dissection and a urinary diversion (UD) are the gold standard treatments for UUTUC and muscle-invasive bladder cancer (MIBC), respectively. These two treatments can be performed simultaneously when a bilateral or unilateral UUTUC is present with a MIBC, and are called complete urinary tract extirpation (CUTE) and hemi-CUTE, respectively. This complex surgery can help the patient by avoiding multi-staged surgeries, repeated anesthesia, and delay in completion of treatment. Herein, we report the first cases of a hemi-CUTE and CUTE in our department and share our experience with this aggressive and complex surgical treatment.

Adjuvant carboplatin and paclitaxel after concurrent cisplatin and radiotherapy in patients with locally advanced cervical cancer.

INTRODUCTION: Standard treatment for locally advanced cervical cancer (LACC) includes concomitant chemoradiotherapy (CRT) that typically controls localized disease. However, most patients develop distant metastasis, ultimately leading to death. OBJECTIVE: To determine the role of adjuvant carboplatin and paclitaxel for clinical outcomes in patients with LACC. METHODS: Between 2010 and 2017, 109 patients with LACC were retrospectively evaluated. All patients received cisplatin (40 mg/m2) with concurrent external-beam radiotherapy (up to 50.4 Gy), followed by intra-cavitary brachytherapy. Forty-six of 109 patients received a median of six cycles (range 3-6 cycles) of adjuvant chemotherapy consisting of paclitaxel (175 mg/m2) and carboplatin (CRT + chemotherapy group; area under the curve 5). The remaining 63 patients did not receive adjuvant chemotherapy (CRT group). RESULTS: Disease-free survival and overall survival after a median follow-up of 24.5 months (range 2.6-94.75 months) were 93.5% and 95.7% and 69.8% and 82.5 % for the CRT + chemotherapy and CRT groups, respectively (p = 0.001, p = 0.012, respectively). No acute grade 3/4 gastrointestinal or genitourinary toxicities were seen during CRT. During adjuvant chemotherapy, the most troublesome side effects were hematologic and neurologic toxicities; however, most were manageable. No chronic grade 3/4 genitourinary toxicities were seen. DISCUSSION: Adjuvant chemotherapy in patients with LACC significantly improved both disease-free survival and overall survival without increasing unmanageable toxicity. Future larger prospective trials are warranted to verify these findings.

Beta-Hydroxy-Beta-Methyl-Butyrate, L-glutamine, and L-arginine Supplementation Improves Radiation-Induce Acute Intestinal Toxicity.

We aimed to evaluate effects of ß-hydroxy-ß-methylbutyrate, L-glutamine, and L-arginine (HMB/GLN/ARG) on radiation-induced acute intestinal toxicity. Forty rats were divided into four groups: group (G) 1 was defined as control group, and G2 was radiation therapy (RT) control group. G3 and G4 were HMB/GLN/ARG control and RT plus HMB/GLN/ARG groups, respectively. HMB/GLN/ARG started from day of RT and continued until the animals were sacrificed 10 days after RT. The extent of surface epithelium smoothing, villous atrophy, lamina propria inflammation, cryptitis, crypt distortion, regenerative atypia, vascular dilatation and congestion, and fibrosis were quantified on histological sections of intestinal mucosa. Statistical analyses were performed using the analysis of variance (ANOVA) test. There were significant differences between study groups regarding extent of surface epithelium smoothing, villous atrophy, lamina propria inflammation, cryptitis and crypt distortion, regenerative atypia, vascular dilatation and congestion, and fibrosis (p values were 0.019 for fibrosis, <.001 for the others). Pair-wise comparisons revealed significant differences regarding surface epithelium smoothing, villous atrophy, lamina propria inflammation, cryptitis, vascular dilatation, and congestion between G2 and G4 (p values were <.001, .033, <.001, .007, and <.001, respectively). Fibrosis score was significantly different only between G1 and G2 (p = .015). Immunohistochemical TGF-ß score of G2 was significantly higher than G1 and G3 (p values were .006 and .017, respectively). There was no difference between TGF-ß staining scores of G2 and G4. Concomitant use of HMB/GLN/ARG appears to ameliorate radiation-induced acute intestinal toxicity; however, this finding should be clarified with further studies.

Locally advanced squamous cell cervical cancer in a patient with septate uterus.

A 33-year-old premenopausal multiparous woman with the history of septate uterus was referred to the hospital with menorrhagia and inter-menstrual bleeding occurring for the last 6 months. Work-up revealed a stage IIB cervical cancer. The patient underwent curative chemo/radiotherapy. The patient's septate uterus presented several difficulties during application. Brachytherapy was applied using standard computed tomography-compatible tandem and ovoids. The high-risk clinical target volume (HR-CTV), intermediate risk CTV, and organs at risk were contoured according to the Groupe Européen de Curiethérapie - European Society for Radiology and Oncology (GEC-ESTRO) guidelines. Treatment was performed via 3-dimensional high-dose-rate technique with 192Ir, with brachytherapy dose of 28 Gy in 4 fractions/7 Gy each, prescribed to the HR-CTV. Treatment was well tolerated with manageable acute toxicities. To the best of our knowledge, the current case is the second case of septate uterus with locally advanced cervical carcinoma. Due to the lack of guidelines about brachytherapy applications in patients with uterine anomaly and owing to the anatomical anomaly, brachytherapy application is challenging in this patients population.

Pelvic radiotherapy does not deteriorate the quality of life of women with gynecologic cancers in long-term follow-up: A 2 years prospective single-center study.

PURPOSE: To evaluate the emotional, sexual and health-related quality of life (HRQoL) concerns of the women with gynecologic malignancy treated with curative radiotherapy (RT). PATIENTS AND METHODS: A 100 women with diagnosis of gynecologic malignancy were prospectively enrolled. HRQoL at baseline, at the end of RT and during follow-up was assessed using European Organization for Research and Treatment of Cancer QoL Questionnaire-C30 (EORTC QLQ-C30), EORTC QLQ-cervical cancer module 24, and Hospital Anxiety and Depression Scale. RESULTS: The appetite loss, diarrhea, fatigue, dyspnea, insomnia, nausea and vomiting, pain scores, and sexual activity and sexual enjoyment scores were deteriorated after RT (P = 0.02 for pain scores and P < 0.001 for all other). Body image scores were higher in patients with endometrial cancer (P < 0.01). The emotional function, nausea and vomiting, body image and symptom experience scores were higher in patients who underwent chemotherapy (P = 0.04 and P = 0.01). All the complaints of patients improved during follow-up period. The global health status scores and the level of depression deteriorated in patients with locoregional recurrent disease and distant metastasis. The anxiety (P = 0.001) and depression (P = 0.007) levels were higher in basal and after-RT visits but then decreased through the subsequent follow-up visits. CONCLUSION: Although pelvic RT deteriorated HRQoL in patients with gynecologic malignancy, HRQoL improved during the follow-up period. The progressive disease had a negative impact on HRQoL.

Spironolactone ameliorates the cardiovascular toxicity induced by concomitant trastuzumab and thoracic radiotherapy.

AIM: We aimed to evaluate impact of spironolactone (S) on cardiovascular toxicity of concomitant use of radiotherapy (RT) and trastuzumab (T). BACKGROUND: S, an aldosterone receptor antagonist, is known to ameliorate the cardiac damage. S ameliorates anthracycline -induced cardiotoxicity, there is no data regarding to effect of S on both T and radiation-induced cardiotoxicity. MATERIALS/METHODS: Eighty rats were divided into eight groups: group (G) 1 was defined as control group. G2, G3 and G4 were RT, S and T groups respectively. G5, G6, G7 and G8 were RT + T, T + S, RT + S and RT + T + S groups respectively. Rats were sacrificed at 6th hour; 21st and 100th days after RT. Heart and thoracic aorta samples were taken for microscopical examination. RESULTS: Cardiac inflammation and fibrosis scores and; TGF-ß expression were not significantly different within study groups at 6th hour and 21st days of RT. By 100th days of RT fibrosis scores and TGF-ß expression in cardiac samples were significantly different between study groups (p values were 0.004 and 0.002 respectively). Pair-wise comparisons revealed that both cardiac fibrosis scores and TGF-ß expression levels were higher in G5 when compared to G8 (p values were 0.046 and 0.028 respectively). Moreover the TGF-ß expression was higher in G5 when compared to G2 (p = 0.046). We could not demonstrate any significant differences with respect to inflammation, fibrosis and TGF-ß expression in thoracic aorta samples between study groups. CONCLUSIONS: Although S had a protective effect on cardiac tissue it had no protective effect on thoracic aorta when administered with RT + T.

An aggressive parameningeal rhabdomyosarcoma with multiple spinal cord metastases: a case report and review of the literature.

PURPOSE: Spinal cord metastasis from rhabdomyosarcoma (RMS) is extremely rare, with three cases reported to date. Herein, we report an aggressive case of RMS of the infratemporal fossa who which developed spinal cord metastases during treatment. CASE PRESENTATION: A 6-year-old girl presented with an enlarging painless mass around her right ear for 3 months. An enhanced magnetic resonance imaging (MRI) revealed a 5 × x4 × x4.5 5 cm mass on her right infratemporal fossa. A tru-cut biopsy was performed, and histopathologic examination revealed the diagnosis of rhabdomyosarcoma. At the time of the diagnosis, cerebrospinal fluid cytology was negative for malignant cells. The patient underwent induction chemotherapy. There was minimal response to chemotherapy, and the patient underwent curative radiotherapy. However, by 12th fraction of RT, the patient developed a progressive weakness on her lower extremity. Spinal MRI revealed multiple gross masses in different parts of the spinal cord. The local radiotherapy was changed toas craniospinal radiotherapy. However, two 2 weeks after the completion of the RT, the patient developed sepsis and expired because of septic shock. CONCLUSION: Parameningeal RMS is a peculiar subgroup of RMS, which needs an aggressive approach. Despite aggressive approach, meningeal spread is the most important cause of the treatment failure. We should keept in mind that during the treatment, there can be meningeal spread towards to either the brain or spinal cord; therefore, we should follow -up the patients closely from this aspect.