Prognostic value of pretreatment temporal muscle thickness after curative surgery for oral cavity squamous cell carcinoma.

BACKGROUND: Sarcopenia is a poor prognostic factor in various diseases. Temporal muscle thickness (TMT) has been reported to be associated with sarcopenia. We investigated the prognostic value of TMT in patients with oral squamous cell carcinoma. METHODS: This study included 61 patients with oral squamous cell carcinoma. Two board-certified otolaryngologists measured TMT based on pre-treatment CT. The following sex-specific TMT cut-off values were used in accordance with previous reports: ≤ 6.3 mm in men, and ≤ 5.2 mm in women. We classified patients into normal TMT group and low TMT group according to the cutoff values. The correlation between the TMT measurements of the two readers was tested using the interclass correlation coefficient (ICC). Cox regression models were used to verify the association between TMT and prognostic factors. RESULTS: The low TMT group had a significantly lower BMI than the normal TMT group. Patients with low TMT at baseline had a significantly higher risk of death than those with normal TMT (hazard ratio 4.51; 95% confidence interval [CI] 1.49-13.61; p = 0.0076). There were no significant differences in disease-specific survival between the two groups. The correlation between the two evaluators' TMT measurements was excellent (ICC 0.988, 95% CI 0.981-0.933). CONCLUSIONS: Sex-specific TMT was associated with overall survival in patients with oral squamous cell carcinoma. TMT is easy to assess and its measurement is consistent between evaluators.

Temporal and masseter muscle evaluation by MRI provides information on muscle mass and quality in acromegaly patients.

PURPOSE: The impact of GH/IGF-1 levels on skeletal muscle in acromegaly is still controversial. Temporal (TMT) and masseter muscle (MMT) thickness has been recently demonstrated as a reliable measure of muscle mass. We aimed to investigate the relationship between TMT, MMT and clinical/biochemical characteristics in patients with acromegaly. METHODS: Single center retrospective longitudinal study including 69 patients with at least one available brain/sella turcica MRI and matched clinical data. TMT, MMT, and muscle fatty infiltration (modified Goutallier score) were evaluated in all patients at baseline (first available MRI) and over time (182 MRIs analyzed). RESULTS: At baseline, both TMT and MMT were higher in males than females (p = 0.001 and p = 0.016, respectively). TMT and MMT were positively associated (ß 0.508, p < 0.001), and they were positively correlated with IGF-1 xULN (TMT, p = 0.047; MMT, p = 0.001). MMT had a positive correlation with patients' weight (p = 0.015) and height (p = 0.006). No correlation was found between TMT, MMT and the presence of hypogonadism. Considering all available MRIs, sex and IGF-1 xULN were significant determinants of TMT and MMT at multivariable analysis (female sex: ß -0.345/-0.426, p < 0.001; IGF-1 xULN: ß 0.257/0.328, p < 0.001). At longitudinal evaluation, uncontrolled patients at baseline showed a significant reduction of MMT over time (p = 0.044). Remarkable fatty infiltration was observed in 34-37% of MRIs; age was the main determinant (temporal muscle: OR 1.665; p = 0.013; masseter muscle: OR 1.793; p = 0.009). CONCLUSION: Male patients with higher IGF-1 values have thicker temporal and masseter muscles, suggesting that sex and IGF-1 have a significant impact on muscle mass in acromegaly.

The relationship between prognosis and temporal muscle thickness in 102 patients with glioblastoma.

Temporal muscle thickness measured on 3D MRI has recently been linked to prognosis in glioblastoma patients and may serve as an independent prognostic indicator. This single-center study looked at temporal muscle thickness and prognosis in patients with primary glioblastoma. Overall survival was the major study outcome. For a retrospective analysis from 2010 to 2020, clinical data from 102 patients with glioblastoma at the Department of Oncology Radiotherapy of the First Affiliated Hospital of Dalian Medical University were gathered. Fifty-five cases from 2016 to 2020 contained glioblastoma molecular typing data, of which 45 were IDH wild-type glioblastomas and were analysed separately. TMT was measured on enhanced T1-weighted magnetic resonance images in patients with newly diagnosed glioblastoma.Overall patient survival (OS) was calculated by the Kaplan-Meier method and survival curves were plotted using the log-rank-sum test to determine differences between groups, and multifactorial analyses were performed using a Cox proportional-risk model.The median TMT for 102 patients was 6.775 mm (range: 4.95-10.45 mm). Patients were grouped according to median TMT, and the median overall survival (23.0 months) was significantly longer in the TMT > median group than in the TMT median group (P 0.001; Log-rank test). Analysing 45 patients with IDH wild type alone, the median overall survival (12 months) of patients in the TMT > median group was significantly longer than that of patients in the TMT ≤ median group (8 months) (P < 0.001; Log-rank test).TMT can serve as an independent prognostic factor for glioblastoma.

Automated temporalis muscle quantification and growth charts for children through adulthood.

Lean muscle mass (LMM) is an important aspect of human health. Temporalis muscle thickness is a promising LMM marker but has had limited utility due to its unknown normal growth trajectory and reference ranges and lack of standardized measurement. Here, we develop an automated deep learning pipeline to accurately measure temporalis muscle thickness (iTMT) from routine brain magnetic resonance imaging (MRI). We apply iTMT to 23,876 MRIs of healthy subjects, ages 4 through 35, and generate sex-specific iTMT normal growth charts with percentiles. We find that iTMT was associated with specific physiologic traits, including caloric intake, physical activity, sex hormone levels, and presence of malignancy. We validate iTMT across multiple demographic groups and in children with brain tumors and demonstrate feasibility for individualized longitudinal monitoring. The iTMT pipeline provides unprecedented insights into temporalis muscle growth during human development and enables the use of LMM tracking to inform clinical decision-making.

Case series: Noninfectious myositis of temporal muscle: a report of 2 cases.

BACKGROUND: Noninfectious myositis (NIM) of the masticatory muscles is uncommon local myalgia disorder persisted by a centrally-mediated neurogenic mechanism. Due to the rarity of this condition and the lack of appropriate data regarding it, diagnosing this pathology when it affects the temporal muscle (TM) is challenging. CASE PRESENTATION: Clinical signs and symptoms, diagnostic process, and treatment outcome of 2 rare cases of NIM of the TM were presented. The signs and symptoms of the patients were not pathognomonic. There were restrictions on the mouth opening and lateral excursion of the mandible. The duration of the symptoms may not be chronic. The findings of clinical evaluation may indicate the diagnosis of anterior disc displacement (DD) without reduction of the temporomandibular joint (TMJ) and/or local myalgia. Swelling of the involved muscle could be evident and identified on palpation depending on the involved site of myositis. The axial T2-weighted magnetic resonance (MR) imaging was important for the accurate diagnosis of this rare condition. Application of non-surgical conservative treatment modalities such as administration of non-steroidal anti-inflammatory analgesics for a sufficient period of time, control of oral parafunctional habits, and jaw exercises were effective for the management of NIM of the TM. CONCLUSION: A thorough clinical examination and MR imaging including the axial T2-weighted view are required for accurate diagnosis and effective management of NIM of the TM.

Prognostic value of temporal muscle thickness, a novel radiographic marker of sarcopenia, in patients with brain tumor: A systematic review and meta-analysis.

Sarcopenia has been identified as a prognostic factor among certain types of cancer. However, it is unclear whether there is prognostic value of temporalis muscle thickness (TMT), a potential surrogate for sarcopenia, in adults patients with brain tumors. Therefore, we searched the Medline, Embase, and PubMed to systematically review and meta-analyze the relationship between TMT and overall survival, progression-free survival, and complications in patients with brain tumors and the hazard ratio (HR) or odds ratios (OR), and 95% confidence interval (CI) were evaluated. The quality in prognostic studies (QUIPS) instrument was employed to evaluate study quality. Nineteen studies involving 4570 patients with brain tumors were included for qualitative and quantitative analysis. Meta-analysis revealed thinner TMT was associated with poor overall survival (HR, 1.72; 95% CI, 1.45-2.04; P < 0.01) in patients with brain tumors. Sub-analyses showed that the association existed for both primary brain tumors (HR, 2.02; 95% CI, 1.55-2.63) and brain metastases (HR, 1.39; 95% CI, 1.30-1.49). Moreover, thinner TMT also was the independent predictor of progression-free survival in patients with primary brain tumors (HR, 2.88; 95% CI, 1.85-4.46; P < 0.01). Therefore, to improve clinical decision making it is important to integrate TMT assessment into routine clinical settings in patients with brain tumors.

The possible relation between temporal muscle mass and glioblastoma multiforme prognosis via sarcopenia perspective.

BACKGROUND: The optimal sarcopenia measurement method in patients with a diagnosis of glioblastoma multiforme (GBM) is unknown. It has been found that temporal muscle thickness (TMT) may reflect sarcopenia and be associated with survival, but the relationship between temporal muscle area (TMA) and GBM prognosis has never been evaluated before. The primary outcome of the study was to evaluate the relationship between TMA/TMT and overall survival (OS) time in newly diagnosed GBM patients. METHODS: The data of patients who presented at the university hospital between January 2009 and January 2019 with a confirmed diagnosis of glioblastoma multiforme at the time of diagnosis were analyzed retrospectively. Temporal muscle thickness and TMA were measured retrospectively from preoperative MRIs of patients diagnosed with GBM. Due to the small number of patients and the failure to determine a cut-off value with acceptable sensitivity and specificity using ROC analysis, the median values were chosen as the cut-off value. The patients were basically divided into two according to their median TMT (6.6 mm) or TMA (452 mm2 ) values, and survival analysis was performed with the Kaplan-Meier analysis. RESULTS: The median TMT value was 6.6 mm, and the median TMA value was 452 mm2 . The median overall survival (OS) was calculated as 25.8 months in patients with TMT < 6.6 mm, and 15.8 months in patients with TMT ≥ 6.6 mm (p = 0.29). The median overall survival (OS) of patients with TMA < 452mm2 was 26.3 months, and the group with TMA ≥ 452mm2 was 14.6 months (p = 0.06). The median disease-free survival was 18.3 months (%95 CI: 13.2-23.4) in patients with TMT < 6.6mm, while mDFS was 10.9 (%95 CI: 8.0-13.8) months in patients with TMT ≥ 6.6mm (p = 0.21). The median disease-free survival was found to be 21.0 months (%95 CI: 15.8-26.1) in patients with TMA < 452 mm2 and 10.5 months (%95 CI: 7.8-13.2) in patients with TMA ≥ 452 mm2 (p = 0.018). DISCUSSION: No association could be demonstrated between TMT or TMA and OS of GBM patients. In addition, the median DFS was found to be longer in patients with low TMA. There is an unmet need to determine the optimal method of sarcopenia in GBM patients.

Temporal muscle thickness as an independent prognostic marker in glioblastoma patients-a systematic review and meta-analysis.

Glioblastoma is the most common primary malignant brain tumor in the adult population. It causes the patient to incur a great deal of malady. Even with the advances in management and the Stupp protocol in place, the prognosis remains grim. There are various parameters to evaluate patients' performance status and frailty pre-operatively, but these are mostly subjective and thus suffer from inter-observer variability. Assessment of sarcopenia serves as an objective parameter to assess the patient's performance status pre-operatively. Temporalis muscle thickness serves as a surrogate to assess sarcopenia in patients with glioblastoma. We conducted a literature review and meta-analysis to determine the prognostic implications of temporalis muscle thickness in 3283 patients with primary glioblastoma. The pooled overall survival hazard's ratio of thick versus thin TMT was 0.54. The pooled progression-free survival hazard's ratio of thick versus thin TMT was 0.38. Thus, the main finding of this study is that thicker temporal muscle is associated with better OS and PFS as compared to thinner temporal muscle. We thus conclude that TMT is a viable surrogate for predicting sarcopenia and survival in primary glioblastoma. TMT measurement is extremely easy and can be incorporated as a part of the routine neurosurgical workflow in these patients. Survival prediction will help inform treatment decisions in glioblastoma patients having poor prognosis, at the initial diagnosis itself.

Correlation of reduced temporal muscle thickness and systemic muscle loss in newly diagnosed glioblastoma patients.

PURPOSE: Reduced temporal muscle thickness (TMT) has recently been postulated as a prognostic imaging marker and an objective tool to assess patients frailty in glioblastoma. Our aim is to investigate the correlation of TMT and systemic muscle loss to confirm that TMT is an adequate surrogate marker of sarcopenia in newly diagnosed glioblastoma patients. METHODS: TMT was assessed on preoperative MR-images and skeletal muscle area (SMA) was assessed at the third lumbar vertebra on preoperative abdominal CT-scans. Previous published TMT sex-specific cut-off values were used to classify patients as 'patient at risk of sarcopenia' or 'patient with normal muscle status'. Correlation between TMT and SMA was assessed using Spearman's rank correlation coefficient. RESULTS: Sixteen percent of the 245 included patients were identified as at risk of sarcopenia. The mean SMA of glioblastoma patients at risk of sarcopenia (124.3 cm2, SD 30.8 cm2) was significantly lower than the mean SMA of patients with normal muscle status (146.3 cm2, SD 31.1 cm2, P < .001). We found a moderate association between TMT and SMA in the patients with normal muscle status (Spearman's rho 0.521, P < .001), and a strong association in the patients at risk of sarcopenia (Spearman's rho 0.678, P < .001). CONCLUSION: Our results confirm the use of TMT as a surrogate marker of total body skeletal muscle mass in glioblastoma, especially in frail patients at risk of sarcopenia. TMT can be used to identify patients with muscle loss early in the disease process, which enables the implementation of adequate intervention strategies.

Association between Temporal Muscle Thickness and Overall Survival in Non-Small Cell Lung Cancer Patients with Brain Metastasis.

Temporal muscle thickness (TMT) has recently been suggested as a novel biomarker of sarcopenia in head and neck malignancies. However, few studies have evaluated TMT as a prognostic marker in patients with brain metastasis. This study investigated the association of TMT with overall survival (OS) in non-small cell lung cancer (NSCLC) patients with brain metastasis. The records of all NSCLC patients with brain metastasis between 2009 and 2018 at St. Vincent's Hospital were reviewed retrospectively. A total of 221 patients met our eligibility criteria. In the group with TMT thicker than the median, OS was longer than the group with TMT thinner than the median (240 days versus 139 days, p = 0.014). In multivariate analysis, the thicker TMT group had longer survival (HR 0.73 CI 0.56−0.96, p = 0.024). Male (HR 1.58 CI 1.19−2.09, p = 0.002) and older age (≥65 years) (HR 2.05 CI 1.53−2.74, p < 0.001) also showed statistical significance. We also performed subgroup analysis in older patients (≥65 years). In this subgroup of 107 patients, the thicker TMT group also showed longer OS than the thinner TMT group (209 days versus 82 days, p = 0.009). Our findings suggest that TMT can be a useful biomarker for OS in NSCLC patients with brain metastasis.

Temporal muscle thickness and survival in patients with amyotrophic lateral sclerosis.

Temporal muscle thickness (TMT) is a new potential MRI biomarker, which has shown prognostic relevance in neuro-oncology. We aim at investigating the potential prognostic value of TMT in patients with Amyotrophic Lateral Sclerosis (ALS). We retrospectively evaluated 30 ALS patients, whose clinical, Magnetic Resonance Imaging (MRI) and Electrodiagnostic testing (EDX) data were available, in comparison to age-matched 30 healthy subjects. TMT calculated on T1-weighted MR images was significantly lower in ALS patients than in healthy subjects (p < 0.001), correlating with the ALS Functional Rating Scale (FRS) (p:0.018) and compound motor action potential (CMAP) (p:0.012) in the patients group. Multivariate analysis of overall survival (OS) showed that the only parameters that remained significant were TMT (p:0.002, OR 0.45, 95%vCI: 0.28-0.75) and ALS FRS-R (p:0.023, OR: 0.80, 95%CI: 0.67-0.92). TMT seems to be a promising surrogate biomarker of survival and functional status in ALS. Our data deserve further investigations in multicenter and prospective trials.

Review of cysticercosis of maxillofacial region and report of two cases.

Cysticercosis is a parasitic infection caused by the larval stage of Taenia solium, which very rarely manifests in the maxillofacial region. It usually presents as a painless swelling. The most common site for maxillofacial cysticercosis are the tongue and lips. When humans accidently ingest the eggs of Taenia solium, they become the intermediate host, a role which is typically played by pig. This paper describes two cases of cysticercosis cellulosae, presenting as non-tender swelling of left buccal mucosa and left temporalis region respectively. Case reports available on PubMed were searched and a review was performed. Excision of cystic lesion was the treatment modality in majority of published reports. It is emphasised that cysticercosis should be considered in differential diagnosis of solitary painless swellings of oral and maxillofacial region, especially in patients from an endemic region.

Characterization of lesions in the temporal muscle and the male reproductive system (epididymis and testicle) of dogs experimentally infected with Leishmania infantum with different clinical stages.

Leishmaniosis is a zoonotic disease with a very complex pathogenesis modulated by the interaction between the parasite, the vector and the host. Although the pathological characteristics have been extensively studied in the typically affected organs, some locations such as muscles and reproductive organs have been less studied. The objective of this study was to evaluate the presence of lesions in the temporal muscle and the male reproductive organs (testicle and epididymis) and correlate their characteristics with the presence of the parasite and with the clinical status of the dogs. The temporal muscle was studied in 25 infected beagle dogs (nine females and 16 males) and five uninfected control dogs (two females and three males) and the testicle and epididymis in the 19 males. Dogs were euthanized one year after infection and clinical signs, anti-Leishmania serum antibodies, and lymph node parasite load were assessed. Muscular and reproductive lesions were characterized by H&E and immunohistochemistry (IHC). The presence of the parasite in the lesions was evaluated using IHC and molecular techniques. Myositis was observed in 72% (18/25) of the dogs and was characterized by lymphoplasmacytic or histiocytic lesions. Mild and severe lesions were detected, the latter being statistically associated with the presence of the parasite and with the clinical status of the dogs. Orchitis was observed in 50% (8/16) of the dogs and was mainly mild and lymphoplasmacytic. No statistical relationship was found between testicular lesions and the presence of the parasite or the clinical status. Epididymitis was observed in 87.5% (14/16) of the dogs, and the lesions were often infiltrated by numerous histiocytes and neutrophils. Epididymal lesions were statistically associated with the clinical status of the dogs and with the presence of the parasite in the lesions. IgG and IgM immunoglobulins were found in all lesions, suggesting a local immune response with reactivation of the infection. Leishmania was more frequently detected in severe and histiocytic lesions, although some lesions had no detectable parasites. These results have shown that lesions in the temporal muscle, epididymis, and testicles are common in dogs infected by Leishmania infantum and that dogs may show a different response to infection. This response is characterized by varying degrees of cellular and immune responses associated with a variable presence of the parasite.

Temporal Muscle and Stroke-A Narrative Review on Current Meaning and Clinical Applications of Temporal Muscle Thickness, Area, and Volume.

BACKGROUND: Evaluating muscle mass and function among stroke patients is important. However, evaluating muscle volume and function is not easy due to the disturbances of consciousness and paresis. Temporal muscle thickness (TMT) has been introduced as a novel surrogate marker for muscle mass, function, and nutritional status. We herein performed a narrative literature review on temporal muscle and stroke to understand the current meaning of TMT in clinical stroke practice. METHODS: The search was performed in PubMed, last updated in October 2021. Reports on temporal muscle morphomics and stroke-related diseases or clinical entities were collected. RESULTS: Four studies reported on TMT and subarachnoid hemorrhage, two studies on intracerebral hemorrhage, two studies on ischemic stroke, two studies on standard TMT values, and two studies on nutritional status. TMT was reported as a prognostic factor for several diseases, a surrogate marker for skeletal muscle mass, and an indicator of nutritional status. Computed tomography, magnetic resonance imaging, and ultrasonography were used to measure TMT. CONCLUSIONS: TMT is gradually being used as a prognostic factor for stroke or a surrogate marker for skeletal muscle mass and nutritional status. The establishment of standard methods to measure TMT and large prospective studies to further investigate the relationship between TMT and diseases are needed.

Temporalis muscle thickness as an indicator of sarcopenia predicts progression-free survival in head and neck squamous cell carcinoma.

Temporalis muscle thickness (TMT) on brain magnetic resonance imaging (MRI) is correlated with sarcopenia and can be a predictive marker for survival in patients with brain tumors, but the association of TMT on head and neck computed tomography (CT) with survival in head and neck squamous cell carcinoma (HNSCC) remains unclear. We investigated whether TMT on CT could predict progression-free survival (PFS) in patients with HNSCC. A total of 106 patients with newly diagnosed HNSCC were included in this retrospective study. The patients underwent baseline head and neck CT and/or MRI between July, 2008 and August, 2018. The correlation between TMT on CT and MRI was tested using intraclass correlation coefficient (ICC). The cut-off value of TMT on CT for determining tumor progression was identified using receiver-operating characteristic curve analysis. Uni- and consecutive multi-variable Cox regression models were used to verify the association between TMT and PFS. TMT on CT and MRI showed excellent correlation (ICC, 0.894). After a mean follow-up of 37 months, 49 out of 106 patients showed locoregional recurrence and/or distant metastasis. The cut-off TMT of 6.47 mm showed good performance in predicting tumor progression (area under the curve, 0.779). The Cox regression model showed that TMT ≤ 6.24 mm (median value in study population) was a significant contributing factor for predicting shorter PFS (hazard ratio 0.399; 95% confidence interval 0.209-0.763; P = .005). TMT may be used as a surrogate parameter for pre-treatment sarcopenia and could help predict PFS in patients with HNSCC.

An unusual location of a cavernous hemangioma: a case report.

Hemangiomas are benign vascular tumors that most often affect the skin, mucous membranes, subcutaneous tissues, bone and on rare occasions muscles. In the head and neck region, the masseter and trapezius muscles are most often affected; the temporalis muscle involvement is extremely rare. It is a childhood pathology that rarely occurs in adults. We report a case of a cavernous hemangioma in a 37-year-old female. Through this case and in the light of literature we focus on the clinicopathological aspects of this tumor and the rarity of this location.

The association of BMI and sarcopenia with survival in patients with glioblastoma multiforme.

Background: The association between obesity and sarcopenia (via temporal muscle thickness) with overall survival (OS) has been evaluated in several glioblastoma multiforme studies, however, the data are inconclusive. Methods: The authors conducted meta-analyses via the generic inverse-variance method with a random-effects model. Results: In the pooled analysis of five studies, including 973 patients, patients with lower temporal muscle thickness had significantly decreased OS (HR: 1.62, 95% CI: 1.16-2.28, p = 0.005). The pooled analysis of five studies, including 2131 patients, demonstrated decreased OS in patients with lower BMI compared with patients with obesity (HR: 1.45, 95% CI: 1.12-1.88, p = 0.005). Conclusion: Readily available body composition parameters could be used for prognosis prediction and to aid in treatment decisions in patients with glioblastoma multiforme.

A novel radiographic marker of sarcopenia with prognostic value in glioblastoma.

OBJECTIVE: Sarcopenia is an important prognostic consideration in surgical oncology that has received relatively little attention in brain tumor patients. Temporal muscle thickness (TMT) has recently been proposed as a novel radiographic marker of sarcopenia that can be efficiently obtained within existing workflows. We investigated the prognostic value of TMT in primary and progressive glioblastoma. METHODS: TMT measurements were performed on magnetic resonance images of 384 patients undergoing 541 surgeries for glioblastoma. Relationships between TMT and clinical characteristics were examined on bivariate analysis. Optimal TMT cutpoints were established using maximally selected rank statistics. Predictive value of TMT upon postoperative survival (PS) was assessed using Cox proportional hazards regression adjusted for age, sex, Karnofsky performance status (KPS), Stupp protocol completion, extent of resection, and tumor molecular markers. RESULTS: Average TMT for the primary and progressive glioblastoma cohorts was 9.55 mm and 9.40 mm, respectively. TMT was associated with age (r = -0.14, p = 0.0008), BMI (r = 0.29, p < 0.0001), albumin (r = 0.11, p = 0.0239), and KPS (r = 0.11, p = 0.0101). Optimal TMT cutpoints for the primary and progressive cohorts were ≤ 7.15 mm and ≤ 7.10 mm, respectively. High TMT was associated with increased Stupp protocol completion (p = 0.001). On Cox proportional hazards regression, high TMT predicted increased PS in progressive [HR 0.47 (95% confidence interval (CI)) 0.25-0.90), p = 0.023] but not primary [HR 0.99 (95% CI 0.64-1.51), p = 0.949] glioblastoma. CONCLUSIONS: TMT correlates with important prognostic variables in glioblastoma and predicts PS in patients with progressive, but not primary, disease. TMT may represent a pragmatic neurosurgical biomarker in glioblastoma that could inform treatment planning and perioperative optimization.

Prognostic relevance of temporal muscle thickness as a marker of sarcopenia in patients with glioblastoma at diagnosis.

OBJECTIVES: Temporal muscle thickness (TMT) is a surrogate marker of sarcopenia, correlated with survival expectancy in patients suffering from brain metastases and recurrent or treated glioblastoma. We evaluated the prognostic relevance of TMT measured on brain MRIs acquired at diagnosis in patients affected by glioblastoma. METHODS: We retrospectively enrolled 51 patients in our Institution affected by methylated MGMT promoter, IDH1-2 wild-type glioblastoma, who underwent complete surgical resection and subsequent radiotherapy with concomitant and maintenance temozolomide, from January 1, 2015, to April 30, 2017. The last clinical/radiological follow-up date was set to September 3, 2019. TMT was measured bilaterally on reformatted post-contrast 3D MPRAGE images, acquired on our 3-T scanner no more than 2 days before surgery. The median, 25th, and 75th percentile TMT values were identified and population was subdivided accordingly; afterwards, statistical analyses were performed to verify the association among overall survival (OS) and TMT, sex, age, and ECOG performance status. RESULTS: In our cohort, the median OS was 20 months (range 3-51). Patients with a TMT ≥ 8.4 mm (median value) did not show a statistically significant increase in OS (Cox regression model: HR 1.34, 95% CI 0.68-2.63, p = 0.403). Similarly, patients with a TMT ≥ 9.85 mm (fourth quartile) did not differ in OS compared to those with TMT ≤ 7 mm (first quartile). The statistical analyses confirmed a significant association among TMT and sex (p = 0.0186), but none for age (p = 0.642) and performance status (p = 0.3982). CONCLUSIONS: In our homogeneous cohort of patients with glioblastoma at diagnosis, TMT was not associated with prognosis, age, or ECOG performance status. KEY POINTS: • Temporal muscle thickness (TMT) is a surrogate marker of sarcopenia and has been correlated with survival expectancy in patients suffering from brain metastases and recurrent or treated glioblastoma. • We appraised the correlation among TMT and survival, sex, age at surgery, and performance status, measured on brain MRIs of patients affected by glioblastoma at diagnosis. • TMT did not show any significant correlation with prognosis, age at surgery, or performance status, and its usefulness might be restricted only to patients with brain metastases and recurrent or treated glioblastoma.