Prognostic factors and treatment outcomes in patients with pleomorphic rhabdomyosarcoma: a population-based cohort study.

BACKGROUND: Pleomorphic rhabdomyosarcoma is a rare sarcoma in adults. The clinical characteristics, outcomes and prognostic factors associated with pleomorphic rhabdomyosarcoma remain unclear. METHODS: We retrospectively analyzed data from the Bone and Soft Tissue Tumor Registry of Japan, and enrolled patients with pleomorphic rhabdomyosarcoma. Disease-specific overall survival, local recurrence-free survival and distant metastasis-free survival were estimated using the Kaplan-Meier method; Cox regression model was used to identify prognostic factors. RESULTS: In total, 182 patients with pleomorphic rhabdomyosarcoma were included. Median age was 63 (range 20-95) years. The lower extremity (48%) was the most frequent tumor origin site, while head and neck were rare (4%). A total of 43 patients (24%) had distant or regional nodal metastases at first presentation. In all cases, the 2-year and 5-year survival rates were 66.3% and 54.1%, respectively. Distant metastasis was a significant poor prognostic factor (Hazard ratio 6.65; 95% confidence intervals, 3.00-14.75, P < 0.0001), with median survival of such patients being 9.4 (95% confidence intervals: 5.3-12.2) months. In 134 localized cases, the 2-year and 5-year survival rates were 91.5% and 68.3%, respectively. Large tumor size and older age were associated with poorer prognosis. Through data from localized and locally curative cases extracted and adjusted by propensity score matching, we found that perioperative chemotherapy did not improve disease-specific overall survival, distant metastasis-free survival or local recurrence-free survival. CONCLUSIONS: Clinical characteristics and outcomes of pleomorphic rhabdomyosarcoma are similar to those of other high-grade soft tissue sarcomas. Pleomorphic rhabdomyosarcoma may be less chemosensitive, and a strategy other than the standard cytotoxic chemotherapy is required to improve its prognosis.

Extended curettage for tumour-induced osteomalacia in the bone.

BACKGROUND: extended curettage is generally used to treat infiltrative bone tumours. However, the extent of the curettage performed in previous studies remains unclear. This study aimed to investigate the efficacy of extended curettage for bone tumour-induced osteomalacia. METHODS: we included 12 patients with tumour-induced osteomalacia who underwent extended curettage at our hospital between 2000 and 2022. Extended curettage was applied in cases where tumour resection could cause functional impairment or necessitate complex reconstruction. We investigated patients' clinical and oncological outcomes. RESULTS: patients had a mean age of 55 (24-81) years, and the median follow-up duration after surgery was 3.9 (1.0-14.0) years. The causative tumours were located in the pelvis and lumbar spine. Imaging revealed the tumours to be of the sclerotic, intertrabecular, lytic and mixed types. Intraoperative 3D fluoroscopy was used in 10 patients. Extended curettage with high-speed burring and adjuvant therapy with cauterization using an electric scalpel and ethanol resulted in a remission rate of 83%; no recurrence or metastasis was observed in cases of early postoperative biochemical remission. In cases where the causative tumour was at the lumbar spine and ischium close to the acetabulum, no postoperative biochemical remission was observed, and conservative treatment was continued. Except for one patient with a tumour in the lumbar spine, all patients could walk without a cane. CONCLUSIONS: extended curettage for bone tumour-induced osteomalacia is oncologically and functionally favourable, especially in cases where resection of the causative tumour could cause functional impairment or necessitate complex reconstruction.

Embryonal and alveolar rhabdomyosarcoma in adolescents/young adults, adults and older adults: a population-based cohort study.

BACKGROUND: The clinical characteristics, outcomes, and prognostic factors of adult embryonal rhabdomyosarcomas (ERMS) and alveolar rhabdomyosarcomas (ARMS), particularly the differences among adolescents/young adults (AYA), adults, and older adults, remain unclear. We assessed the clinicopathological features and survival outcomes of adult patients with ERMS and ARMS in Japan and to compare these features among AYA, adult, and older adult patients. METHODS: We retrospectively analyzed data from the Bone and Soft Tissue Tumor Registry of Japan and enrolled patients aged ≥15 years with ERMS and ARMS. Disease-specific overall survival (DOS) was estimated using the Kaplan-Meier method, and a Cox regression model was used to identify prognostic factors. RESULTS: Among 184 patients with ERMS and ARMS (median age, 27 years; interquartile range, 18-49 years), a high rate of distant and regional nodal metastases was initially observed in 65 (35%) and 66 (36%) cases, respectively. Older age and distant metastasis at first presentation were statistically poor prognostic factors, and histological subtype and site of tumor origin were not associated with DOS. In patients with localized ERMS and ARMS, older age and nodal metastasis were poor prognostic factors; the 5-year DOS rates of patients with and without nodal metastasis were 23% and 72%, respectively. CONCLUSIONS: Older patients with rhabdomyosarcoma had a dismal prognosis, and distant metastasis was a poor prognostic factor. The prognostic factors differed between adult and pediatric patients with rhabdomyosarcoma; biological analyses, such as genome analysis of adult rhabdomyosarcoma and clinical trials with pediatric oncologists, are needed to improve the prognosis of adult rhabdomyosarcoma.

BRAF mutations and concurrent alterations in patients with soft tissue sarcoma.

BRAF alterations, including V600E and non-V600E mutations and fusions, in soft tissue sarcoma (STS) have been identified in a limited case series. Here, we aimed to evaluate the frequency of BRAF mutations and concurrent alterations in STS to understand their therapeutic action. In this retrospective analysis, we included data from 1964 patients with advanced STS who underwent comprehensive genomic profiling tests at hospitals in Japan between June 2019 and March 2023. The prevalence of BRAF and recurrent concurrent gene alterations were also investigated. BRAF mutations were detected in 24 (1.2%) of 1964 STS patients, with a median age of 47 (range 1-69) years. BRAF V600E was detected in 11 (0.6%) of the 1964 patients with STS, BRAF non-V600E mutations in 9 (4.6%), and BRAF fusions were detected in 4 (0.2%). BRAF V600E was identified in 4 (0.2%) cases of malignant peripheral nerve sheath tumors. The most common concurrent alteration was CDKN2A (11 cases, 45.8%), and the frequency was equivalent to that of the BRAF V600E (5/11 cases, 45.5%) and non-V600E (5/9 cases, 55.6%) groups. Recurrent concurrent alterations, such as TERT promoter mutations (7 cases, 29.2%), were detected at the same frequency in the V600E and non-V600E groups. In contrast, TP53 alterations (4/9 cases, 44.4%) and mitogen-activated protein kinase (MAPK)-activating genes, including NF1, GNAQ, and GNA11 (3/9 cases, 33.3%), were identified as relatively higher in the non-V600E group than in the V600E group (each 1/11 case, 9.1%). We identified BRAF alterations at a rate of 1.2% in all patients with advanced STS. Among them, BRAF V600E and BRAF fusions account for 45.8% and 16.7%, respectively. Collectively, our findings support the clinical characteristics and therapeutic strategies for patients with BRAF-altered advanced STS.

Role of perioperative chemotherapy and radiotherapy for localized high-grade malignant peripheral nerve sheath tumor at the extremities and trunk wall: a population-based cohort study.

BACKGROUND: Primary tumor resection is the mainstay of treatment for malignant peripheral nerve sheath tumors. However, the efficacy of perioperative chemotherapy and radiotherapy for malignant peripheral nerve sheath tumors has not been elucidated. METHODS: This retrospective analysis based on a Japanese registry included patients with localized malignant peripheral nerve sheath tumors arising at the extremities and trunk wall. Disease-specific overall survival and local recurrence-free survival were estimated using the Kaplan-Meier method. A Cox regression model was used to identify prognostic factors. Characteristics of groups with or without chemotherapy were adjusted using propensity score matching. RESULTS: In total, 291 patients were included. The 5-year disease-specific overall survival rate was 70.6%. Multivariate analysis of disease-specific overall survival revealed that deep-seated tumors were a poor prognostic factor, but perioperative chemotherapy was not associated with disease-specific overall survival (hazard ratio, 0.81; 95% confidence interval, 0.45-1.43, P = 0.46). Local recurrence was observed in 55 patients (19.0%), and surgical margins (R1 and R2) were significant risk factors. Overall, perioperative chemotherapy did not prolong disease-specific overall survival (5-year disease-specific overall survival: 74.1% vs. 69.3%, P = 0.75) and had limited efficacy in the group with tumor size ≥ 5 cm, although the difference was not statistically significant (5-year disease-specific overall survival: 77.2% vs. 68.6%, respectively, P = 0.13). After adjustment by propensity score matching, perioperative chemotherapy significantly prolonged disease-specific overall survival (5-year disease-specific overall survival: 74.9% vs. 57.1%, P = 0.03), but this effect was not observed in local recurrence-free survival. In all patients, perioperative radiotherapy did not correlate with local recurrence-free survival (hazard ratio, 1.43; 95% confidence interval 0.78-2.62, P = 0.25). CONCLUSIONS: Perioperative chemotherapy had limited efficacy for disease-specific overall survival in patients with localized malignant peripheral nerve sheath tumors.

Systemic inflammation response index (SIRI) as a predictive factor for overall survival in advanced soft tissue sarcoma treated with eribulin.

BACKGROUND: Eribulin is a tubulin and microtubule-targeting drug that has clinical benefit in overall survival (OS) for patients with advanced soft tissue sarcoma. Eribulin's efficacy has been confirmed in several clinical trials, although no clinically useful biomarkers have been identified. We therefore sought to clarify the predictive factor of eribulin treatment, while focusing on systemic inflammation and immune response values. METHODS: This study included 33 advanced STS patients treated with eribulin between March 2016 and September 2019. We evaluated the associations of clinical factors influencing the efficacy of eribulin treatment and systemic inflammatory and immune response, including the neutrophil-to-lymphocyte ratio (NLR), the platelet-to-lymphocyte ratio (PLR), the lymphocyte-to-monocyte ratio (LMR), the systemic inflammation response index (SIRI), and the prognostic nutrition index (PNI), with progression-free survival (PFS) and OS using the Kaplan-Meier method and log-rank test. RESULTS: NLR, LMR, PLR, SIRI, and PNI were unassociated with PFS. Compared with patients with SIRI <1.5, those with an SIRI ≥1.5 had a significantly shorter OS [median OS 15 months (95% confidence interval [CI] 8-not reached) vs. 7 months (95% CI 3-14), P = 0.04]. Moreover, the PFS tended to be shorter for patients with SIRI ≥1.5 who received chemotherapy after eribulin treatment than in those with SIRI >1.5 [median PFS 92.5 days (95% CI 27-204) vs. 133 days (95% CI 36-507), P = 0.08]. CONCLUSIONS: High SIRI values may predict poorer overall survival and the efficacy of subsequent drugs after eribulin treatment among patients with advanced soft tissue sarcoma.

Prognosis and surgical outcome of soft tissue sarcoma with malignant fungating wounds.

OBJECTIVE: Malignant fungating wounds are ulcerating tumors that infiltrate the overlying skin. Little evidence exists regarding the prognosis or treatment of malignant fungating wound in soft tissue sarcoma. This study aimed to reveal the prognosis and outcome of surgical treatment of malignant fungating wound in soft tissue sarcoma. METHODS: We retrospectively reviewed 26 patients with malignant fungating wound in high-grade soft tissue sarcoma between 2005 and 2018. The patients' characteristics, treatments, surgical wound complications, local recurrences and prognoses were analyzed. Overall survival was analyzed using the Kaplan-Meier method and compared with that of the control cohort, consisting of 236 consecutive patients with non-malignant fungating wound high-grade soft tissue sarcoma treated during the same period. RESULTS: Among the 26 patients, undifferentiated pleomorphic sarcoma was the most common subtype. Twenty-three patients, including 20 (87%) and 3 (13%), underwent limb-salvage surgery and amputation, respectively. Among the 20 patients who underwent limb-salvage surgery, 4 (20%) had surgical wound complications, which required additional surgical procedures. Excluding the patients who underwent palliative surgery, local recurrence occurred in 2 patients (11%). The 5-year overall survival rate for all high-grade malignant fungating wound and non-malignant fungating wound patients was 26.0 and 67.3% (P < 0.0001), respectively. CONCLUSIONS: Malignant fungating wounds in soft tissue sarcoma were significantly associated with a poor prognosis; however, the incidence of surgical complications and local recurrence after limb-salvage surgery was comparable to that of general soft tissue sarcoma cases. Limb-salvage surgery should be considered, if possible, to preserve the patient's quality of life because of the dismal prognosis of patients with malignant fungating wound in soft tissue sarcoma.

Pretreatment serum C-reactive protein is a significant prognostic factor in patients with soft tissue metastases.

BACKGROUND: Soft tissue metastasis is rarer than bone metastasis. Patients with soft tissue metastasis generally have a dismal prognosis. The treatment for metastatic lesions is sometimes difficult, because the prognostic factors of patients with soft tissue metastasis remain unelucidated. Therefore, this study aimed to identify these prognostic factors. METHODS: Thirty-one patients with soft tissue metastasis were included in the study. We evaluated associations of overall survival with clinical parameters and inflammatory markers using Kaplan-Meier curves and Cox proportional hazards models. RESULTS: Twelve patients received surgery for soft tissue metastasis, while radiation therapy was performed in six cases. The median overall survival after the detection of soft tissue metastasis was 11 months. Univariate analysis revealed that detection of soft tissue metastasis after the multidisciplinary treatment (P = 0.01); solitary metastasis (P = 0.0003); and pretreatment C-reactive protein (CRP) level < 0.4 mg/dL (P < 0.0001), white blood cell count < 8500 × 103/µL (P = 0.0003), and neutrophil-to-lymphocyte ratio < 5 (P = 0.02) were significant good prognostic factors. Multivariate analysis revealed that a CRP value < 0.4 mg/dL (P = 0.07) and solitary metastasis (P = 0.09) were possible significant predictors of survival. Furthermore, in case of CRP levels <0.4 mg/dL and metastatic tumor resection, patients had a good prognosis; however, when the CRP levels increased to 0.4 mg/dL and above, patients had a poor prognosis, irrespective of tumor resection. CONCLUSIONS: CRP is potentially useful for determining the indication of radical metastasectomy in soft tissue metastasis.

Skeletal muscle measurements predict surgical wound complications but not overall survival in patients with soft tissue sarcoma.

BACKGROUND: It is unknown whether sarcopenia influences treatment outcome in patients with soft tissue sarcoma. Herein, we aimed to elucidate the impact of sarcopenia on sarcoma treatment. METHODS: A total of 163 soft tissue sarcoma patients were included. Skeletal muscle measures were calculated using computed tomography images. Skeletal muscle area (SMA) and density (SMD) at the L3 level were extracted, and SMA was normalized by height as skeletal muscle index (SMI). The skeletal muscle gauge (SMG) was calculated by multiplying SMD × SMI. The relationship of skeletal muscle measures and clinical factors to wound complications and prognosis was evaluated, and classification and regression tree (CART) analysis was used to develop classification models for risk groups of surgical wound complications. RESULTS: Thirty-three patients developed wound complications. In univariate analysis, age (P = 0.0022), tumour location of adductor compartment of the thigh (P = 0.0019), operating time (P = 0.010), blood loss (P = 0.030), SMD (P = 0.0004) and SMG (P = 0.0001) were significantly correlated with complications. In multivariate analysis, lower SMG was an independent risk factor (P = 0.031, OR = 3.27). CART analysis classified three risk groups of surgical wound complications by SMG, age, tumour location and operating time, and area under the receiver operating characteristic curve (AUROCC) was 0.75. SMG was not associated with prognosis in univariate analysis (P = 0.15). CONCLUSIONS: The SMG does not affect overall survival but predicts surgical wound complications.

Body composition as a predictor of toxicity after treatment with eribulin for advanced soft tissue sarcoma.

BACKGROUND: Despite the clinical benefits of eribulin on overall survival of advanced soft tissue sarcoma (STS) patients, treatment-related toxicity reduces their QOL. Body composition metrics (BCMs) are associated with poor outcome and drug toxicities in several cancers. This study investigated whether BCMs could predict drug toxicity occurrence in advanced STS patients treated with eribulin. METHODS: This study included 23 advanced STS patients treated with eribulin between March 2016 and April 2018. BCMs were evaluated using a CT scan obtained within 1 month before or after treatment initiation. The relationship of BCMs and other clinical factors was evaluated and CART analysis used to develop classification models for risk groups of drug toxicity. RESULTS: Sixteen patients (69.6%) experienced any grade 3/4 toxicity. Eleven patients (47.8%) developed G4 hematologic toxicity, which was significantly higher in those with low skeletal muscle gauge (SMG) (P = 0.02) and low pretreatment neutrophil count (P = 0.0002). Six patients (26.1%) had grade 3/4 non-hematologic toxicity, and was higher in those with low SMG (P = 0.004), and low serum albumin level (P = 0.02). Five patients with high BMI (P = 0.03) experienced febrile neutropenia (FN) and low pretreatment neutrophil count (P = 0.02). CART analysis classified three risk groups, and area under the receiver operating characteristic curve (AUROCC) was 0.92, 0.88, 0.92 in G4 hematologic AE, G3/4 non-hematologic AE, FN, respectively. CONCLUSIONS: SMG is a significant predictive factor of eribulin drug toxicity in advanced STS patients. Risk classification of drug toxicity through combining predictive factors, could improve the therapeutic strategy used in chemotherapy.

Clinical genomic profiling of malignant giant cell tumor of bone: A retrospective analysis using a real­world database.

Malignant giant cell tumor of bone (GCTB) is identified by the presence of multinucleated giant cells, with an aggressive behavior and a high risk of metastasis, which has not been genetically characterized in detail. H3 histone family member 3A (H3F3A) gene mutations are highly recurrent and specific in GCTB. The present study analyzed the clinical information and genomic sequencing data of eight cases of malignant GCTB (out of 384 bone sarcoma samples) using an anonymized genomic database. There were 5 males and 3 females among the cases, with a median age of 33 years at the time of the initial diagnosis. H3F3A G34W and G34L mutations were detected in 3 patients and 1 patient, respectively. In 75% of cases without H3F3A mutation, mitogen-activated protein kinase (MAPK) signaling pathway gene alterations were found (KRAS single nucleotide variant, KRAS amplification, nuclear respiratory factor 1-BRAF fusion). Moreover, the collagen type I alpha 2 chain-ALK fusion was detected in remaining one case. The most frequent gene alterations were related to cell cycle regulators, including TP53, RB1, cyclin-dependent kinase inhibitor 2A/B and cyclin E1 (75%, 6 of 8 cases). On the whole, the present study discovered recurrent MAPK signaling gene alterations or other gene alterations in cases of malignant GCTB. Of note, two fusion genes should be carefully validated following the pathology re-review by sarcoma pathologists. These two fusion genes may be detected in resembling tumors, which contain giant cells, apart from malignant GCTB. The real-world data used herein provide a unique perspective on genomic alterations in clinicopathologically diagnosed malignant GCTB.

Patterns of symptoms and insufficiency fractures in patients with tumour-induced osteomalacia.

The aim of this study was to report the patterns of symptoms and insufficiency fractures in patients with tumour-induced osteomalacia (TIO) to allow the early diagnosis of this rare condition. The study included 33 patients with TIO who were treated between January 2000 and June 2022. The causative tumour was detected in all patients. We investigated the symptoms and evaluated the radiological patterns of insufficiency fractures of the rib, spine, and limbs. The mean age of the patients was 57 years (24 to 87), and the mean duration of pain from onset to time of presentation was 3.9 years (0.75 to 23). The primary symptoms were low back pain (ten patients), chest wall pain (eight patients), and hip pain (eight patients). There were symptoms at more sites at the time of presentation compared with that at the time of the onset of symptoms. Bone scans showed the uptake of tracer in the rib (100%), thoracic and lumbar vertebrae (83%), proximal femur (62%), distal femur (66%), and proximal tibia (72%). Plain radiographs or MRI scans identified femoral neck fractures in 14 patients, subchondral insufficiency fractures of the femoral head and knee in ten and six patients, respectively, distal femoral fractures in nine patients, and proximal tibial fractures in 12 patients. Thoracic or lumbar vertebral fractures were identified in 23 of 29 patients (79.3%) when using any imaging study, and a biconcave deformity was the most common type of fracture. Insufficiency fractures in patients with TIO caused spinal pain, chest wall pain, and periarticular pain in the lower limbs. Vertebral fractures tended to be biconcave deformities, and periarticular fractures of the hips and knees included subchondral insufficiency fractures and epiphyseal or metaphyseal fractures. In patients with a tumour, the presence of one or more of these symptoms and an insufficiency fracture should suggest the diagnosis of TIO.

Prediction of pathological fracture in patients with lower limb bone metastasis using computed tomography imaging.

Lower limb pathological fractures caused by bone metastases can severely impair activities of daily living, so recognizing fracture risk is essential. Medial cortical involvement (MCI) in the proximal femur has been demonstrated to affect bone strength in biomechanical studies, but it has not been investigated in real patients. Between 2012 and 2019, 161 bone metastases with computed tomography (CT) images were retrospectively examined. Twenty-nine fractures were observed including 14 metastases with pathological fractures at the first examination, and prophylactic surgery was performed for 50 metastases. We extracted clinicopathological data using CT images, including patient's background, MCI in the proximal femur, site, size, circumferential cortical involvement (CCI), pain, and nature of metastasis. Cox proportional hazard regression analyses were performed, and we created integer scores for predicting fractures. We revealed that MCI, CCI, lytic dominant lesion, and pain were significant factors by univariate analyses. By multivariable analysis, MCI and each 25% CCI were significant and integer score 1 was assigned based on hazard ratio. The full score was four points, with MCI in the proximal femur (one point) and ≥ 75% CCI (three points). With integer score two, sensitivity was 88.9% and specificity was 81.2% for predicting fracture within 60 days. In conclusion, MCI and CCI examined by CT images were the risk factors for pathological fracture. CCI ≥ 50% is a widely known risk factor, but in addition, it may be better to consider surgery if MCI in the proximal femur is observed in metastasis with 25-50% CCI.

Heterotopic Ossification of the Peroneus Longus Tendon in the Retromalleolar Portion with the Peroneus Quartus Muscle: A Case Report.

Heterotopic ossification (HO) is an ectopic formation of the lamellar bone in the soft tissues. Some authors have previously reported HO or calcific tendinitis of the peroneus longus tendon at the level of the cuboid bone, while the HO of the peroneus longus tendon in the retromalleolar portion has not been reported. The purpose of this report is to describe clinical, radiological, and histological features of this rare ossification and its treatment. To the best of our knowledge, this is the first report presenting a case of HO of the peroneus longus tendon, which developed in the retromalleolar portion.