Efficacy and safety of anlotinib in patients with unresectable or metastatic bone sarcoma: A retrospective multiple institution study

Emerging Treatments Targeting the Tumor Microenvironment for Advanced Chondrosarcoma

Chondrosarcoma (ChS), a malignant cartilage-producing tumor, is the second most frequently diagnosed osseous sarcoma after osteosarcoma. It represents a very heterogeneous group of malignant chemo- and radiation-resistant neoplasms, accounting for approximately 20% of all bone sarcomas. The majority of ChS patients have a good prognosis after a complete surgical resection, as these tumors grow slowly and rarely metastasize. Conversely, patients with inoperable disease, due to the tumor location, size, or metastases, represent a great clinical challenge. Despite several genetic and epigenetic alterations that have been described in distinct ChS subtypes, very few therapeutic options are currently available for ChS patients. Therefore, new prognostic factors for tumor progression as well as new treatment options have to be explored, especially for patients with unresectable or metastatic disease. Recent studies have shown that a correlation between immune infiltrate composition, tumor aggressiveness, and survival does exist in ChS patients. In addition, the intra-tumor microvessel density has been proven to be associated with aggressive clinical behavior and a high metastatic potential in ChS. This review will provide an insight into the ChS microenvironment, since immunotherapy and antiangiogenic agents are emerging as interesting therapeutic options for ChS patients.

Recurrent retroperitoneal liposarcoma with multiple surgeries: a case report

Retroperitoneal liposarcoma (RPLPS) is a rare malignant tumor that is typically treated with surgical resection. However, RPLPS often has a high rate of local recurrence, making it crucial to explore new treatment options. In this report, we present the case of a middle-aged woman who experienced seven recurrences and underwent seven surgeries following the initial resection. Currently, the patient's condition remains stable after the eighth surgery. Although there have been numerous reports of RPLPS cases both domestically and internationally, instances of repeated recurrence like this are exceptionally rare. Therefore, we have gathered the patient's case data and conducted a retrospective analysis, incorporating relevant literature, to enhance the understanding of this disease among clinical practitioners.

Evaluation of the efficacy and safety of immunotherapy in sarcoma: a two-center study

Background

Sarcoma is a highly heterogeneous malignancy with a poor prognosis. Although chemotherapy and targeted therapy have improved the prognosis to some extent, the efficacy remains unsatisfactory in some patients. The efficacy and safety of immunotherapy in sarcoma need further evaluation.

Methods

We conducted a two-center study of sarcoma patients receiving PD-1 immunotherapy at Tianjin Medical University Cancer Institute and Hospital and Henan Provincial Cancer Hospital. The treatment regimens included PD-1 inhibitor monotherapy and combination therapy based on PD-1 inhibitors. The observed primary endpoints were median progression-free survival (mPFS) and median overall survival (mOS). Survival curves were compared using the Kaplan-Meier method.

Results

A total of 43 patients were included from the two centers. The median follow-up time for all patients was 13 months (range, 1-48 months). In the group of 37 patients with advanced or unresectable sarcoma, the mPFS was 6 months (95%CI: 5-12 months), and the mOS was 16 months (95%CI: 10-28 months). The ORR was 10.8% (4/37), and the DCR was 18.9% (7/37). Subgroup analysis showed no significant differences in mPFS (p=0.11) and mOS (p=0.88) between patients with PD-L1 negative/positive expression. There were also no significant differences in mPFS (p=0.13) or mOS (p=0.72) between PD-1 inhibitor monotherapy and combination therapy. Additionally, there were no significant differences in mPFS (p=0.52) or mOS (p=0.49) between osteogenic sarcoma and soft tissue sarcoma. Furthermore, the results showed no significant differences in mPFS (p=0.66) or mOS (p=0.96) between PD-1 inhibitors combined with targeted therapy and PD-1 inhibitors combined with AI chemotherapy. Among the 6 patients receiving adjuvant therapy after surgery, the mPFS was 15 months (95%CI: 6-NA months), and the mOS was not reached. In terms of safety, most adverse events were mild (grade 1-2) and manageable. The most severe grade 4 adverse events were bone marrow suppression, which occurred in 4 patients but resolved after treatment. There was also one case of a grade 4 adverse event related to hypertension.

Conclusion

Immunotherapy is an effective treatment modality for sarcoma with manageable safety. Further inclusion of more patients or prospective clinical trials is needed to validate these findings.

The function and mechanism of PSMD14 in promoting progression and resistance to anlotinib in osteosarcoma

BACKGROUND

Osteosarcoma is a rare bone malignancy that frequently affects adolescents and poses formidable obstacles in its advanced stages. Studies revealed that PSMD14 may be a viable osteosarcoma treatment target. However, PSMD14's function and mechanism in osteosarcoma remain unknown. This study aimed to examine the function and mechanism of PSMD14 in the biological behavior of osteosarcoma and its role in anlotinib resistance.

METHODS

Western blotting, qRT-PCR, and immunohistochemistry (IHC) studies were used to examine PSMD14 levels. The role of PSMD14 in the malignant phenotype of osteosarcoma and its molecular pathway was explored by a series of studies, including Western blotting, cell amplification assay, transwell assay, and tumor growth. Furthermore, a series of in vitro investigations were done to determine the effect of PSMD14 on anlotinib-resistant osteosarcoma cell lines.

RESULTS

PSMD14 expression was elevated in osteosarcoma tissues compared to normal tissues. Overexpression of PSMD14 was associated with osteosarcoma patients' pathological grade and clinical stage, and PSMD14 was an independent poor prognostic factor. PSMD14 knockdown inhibits in vitro cell proliferation, migration, invasion, and in vivo tumor growth. PSMD14 knockdown has the potential to downregulate the PI3K/Akt/mTOR pathway, which was regarded as one of the key mechanisms promoting tumor growth. PSMD14 was likewise overexpressed in anlotinib-resistant OS cell lines, and its knockdown not only reduced the proliferation, migration, and invasion of subline cells and triggered cell apoptosis. Importantly, combination therapy with anlotinib enhanced these effects.

CONCLUSIONS

PSMD14 is substantially expressed in osteosarcoma and may be an independent risk factor associated with poor prognosis. It can promote tumor progression and anlotinib resistance in osteosarcoma and may promote osteosarcoma progression by modulating PI3K/AKT/mTOR signaling pathway.

Tyrosine kinase inhibitors in osteosarcoma: Adapting treatment strategiesa

Osteosarcoma (OS) is an aggressive primary bone malignancy that metastasizes rapidly. The standard of care has changed little over the previous four decades, and survival rates have plateaued. In this context, tyrosine kinase inhibitors (TKIs) emerge as potential treatments. A literature search was conducted to collect data related to receptor tyrosine kinase genetic alterations and expression in OS specimens. Gene amplification and protein expression of these receptors were linked to prognosis and tumor behavior. Relevant TKIs were evaluated as monotherapies and as parts of combination therapies. Certain TKIs, such as apatinib, regorafenib, and cabozantinib, present a potential therapeutic avenue for OS patients, especially when combined with chemotherapy. Producing long-lasting responses and enhancing quality of life remain key goals in OS treatment. To this effect, optimizing the use of TKIs by identifying biomarkers predictive of response and assessing promising TKIs in larger-scale trials to validate the efficacy and safety outcomes relative to these drugs reported in phase II clinical trials. To this effect, it is necessary to identify biomarkers predictive of response to TKIs in larger-scale trials and to validate the efficacy and safety of these drugs reported in phase II clinical trials.

Case report of severe pneumothorax due to lung cancer treated with anlotinib

Anlotinib is a tyrosine kinase inhibitor that targets the vascular endothelial growth factor receptor for the treatment of lung cancer. Pneumothorax is a rare complication of anlotinib treatment. Here, the case of a male patient in his early seventies, with lung cancer combined with emphysema, who developed a pneumothorax during treatment with anlotinib, is described. The patient was admitted to hospital mainly for dyspnoea and was diagnosed with pneumothorax after digital radiography of the chest. The patient's symptoms improved significantly after closed chest drainage, and a repeat chest digital radiography showed a more resolved pneumothorax. The patient had no previous history of pneumothorax. After discontinuation of anlotinib, the latest follow-up chest computed tomography assessment in August 2023 showed no recurrence of pneumothorax, thus, the pneumothorax is presumed to have been associated with anlotinib in this patient. In addition, the authors speculate that emphysema may be a cause of pneumothorax in patients with lung cancer receiving anlotinib treatment. Therefore, clinicians should be alert to the risk of pneumothorax occurrence in patients with emphysema combined with lung cancer who are treated with anlotinib.

Malignant transformation of an aneurysmal bone cyst of the femoral neck: A case report

Aneurysmal bone cyst (ABC) is a benign, distending, osteolytic and locally aggressive bone tumor that is mostly associated with trauma. Approximately 1% of bone tumors are ABCs, which are most prevalent in adolescents and are usually detected in the spine and long tubular bones. The diagnosis of ABC mainly relies on histopathology, malignant transformation is rare, and the chance of malignancy increases if there are multiple recurrences. Due to the rarity of reports of malignant transformation of ABCs into osteosarcoma, there is still considerable debate on the appropriate treatment strategy. The current paper presents a case of aneurysmal bone cyst malignant to osteosarcoma and the therapeutic measures to provide expertise for the diagnosis and treatment of ABCs that are malignant to osteosarcoma.

Tocilizumab (monoclonal anti-IL-6R antibody) reverses anlotinib resistance in osteosarcoma

Purpose

Anlotinib, a tyrosine kinase inhibitor (TKI) has been in clinical application to inhibit malignant cell growth and lung metastasis in osteosarcoma (OS). However, a variety of drug resistance phenomena have been observed in the treatment. We aim to explore the new target to reverse anlotinib resistance in OS.

Materials and Methods

In this study, we established four OS anlotinib-resistant cell lines, and RNA-sequence was performed to evaluate differentially expressed genes. We verified the results of RNA-sequence by PCR, western blot and ELISA assay. We further explored the effects of tocilizumab (anti- IL-6 receptor), either alone or in combined with anlotinib, on the inhibition of anlotinib-resistant OS cells malignant viability by CCK8, EDU, colony formation, apoptosis, transwell, wound healing, Cytoskeletal stain assays, and xenograft nude mouse model. The expression of IL-6 in 104 osteosarcoma samples was tested by IHC.

Results

We found IL-6 and its downstream pathway STAT3 were activated in anlotinib-resistant osteosarcoma. Tocilizumab impaired the tumor progression of anlotinib-resistant OS cells, and combined treatment with anlotinib augmented these effects by inhibiting STAT3 expressions. IL-6 was highly expressed in patients with OS and correlated with poor prognosis.

Conclusion

Tocilizumab could reverse anlotinib resistance in OS by IL-6/STAT3 pathway and the combination treatment with anlotinib rationalized further studies and clinical treatment of OS.

Chordoma recruits and polarizes tumor-associated macrophages via secreting CCL5 to promote malignant progression

BACKGROUND

Chordoma is an extremely rare, locally aggressive malignant bone tumor originating from undifferentiated embryonic remnants. There are no effective therapeutic strategies for chordoma. Herein, we aimed to explore cellular interactions within the chordoma immune microenvironment and provide new therapeutic targets.

METHODS

Spectrum flow cytometry and multiplex immunofluorescence (IF) staining were used to investigate the immune microenvironment of chordoma. Cell Counting Kit-8, Edu, clone formation, Transwell, and healing assays were used to validate tumor functions. Flow cytometry and Transwell assays were used to analyze macrophage phenotype and chemotaxis alterations. Immunohistochemistry, IF, western blot, PCR, and ELISA assays were used to analyze molecular expression. An organoid model and a xenograft mouse model were constructed to investigate the efficacy of maraviroc (MVC).

RESULTS

The chordoma immune microenvironment landscape was characterized, and we observed that chordoma exhibits a typical immune exclusion phenotype. However, macrophages infiltrating the tumor zone were also noted. Through functional assays, we demonstrated that chordoma-secreted CCL5 significantly promoted malignancy progression, macrophage recruitment, and M2 polarization. In turn, M2 macrophages markedly enhanced the proliferation, invasion, and migration viability of chordoma. CCL5 knockdown and MVC (CCL5/CCR5 inhibitor) treatment both significantly inhibited chordoma malignant progression and M2 macrophage polarization. We established chordoma patient-derived organoids, wherein MVC exhibited antitumor effects, especially in patient 4, with robust killing effect. MVC inhibits chordoma growth and lung metastasis in vivo.

CONCLUSIONS

Our study implicates that the CCL5-CCR5 axis plays an important role in the malignant progression of chordoma and the regulation of macrophages, and that the CCL5-CCR5 axis is a potential therapeutic target in chordoma.

Biology and Management of High-Grade Chondrosarcoma: An Update on Targets and Treatment Options

This review provides an overview of histopathology, clinical presentation, molecular pathways, and potential new systemic treatments of high-grade chondrosarcomas (CS), including grade 2−3 conventional, dedifferentiated, and mesenchymal CS. The diagnosis of CS combines radiological and histological data in conjunction with patient clinical presentations. Conventional CS is the most frequent subtype of CS (85%) and represents about 25% of primary bone tumors in adults; they can be categorized according to their bone location into central, peripheral, and periosteal chondrosarcomas. Central and peripheral CS differ at the molecular level with either IDH1/2 mutations or EXT1/2 mutations, respectively. CDKN2A/B deletions are also frequent in conventional CS, as well as COL2A1 mutations. Dedifferentiated CS develops when low-grade conventional CS transforms into a high-grade sarcoma and most frequently exhibits features of osteosarcoma, fibrosarcoma, or undifferentiated pleomorphic sarcoma. Their molecular characteristics are similar to conventional CS. Mesenchymal CS is a totally different pathological entity exhibiting recurrent translocations. Their clinical presentation and management are different too. The standard treatment of CSs is wide en-bloc resection. CS are relatively radiotherapy resistant; therefore, doses >60 Gy are needed in an attempt to achieve local control in unresectable tumors. Chemotherapy is possibly effective in mesenchymal chondrosarcoma and is of uncertain value in dedifferentiated chondrosarcoma. Due to resistance to standard anticancer agents, the prognosis is poor in patients with metastatic or unresectable chondrosarcomas. Recently, the refined characterization of the molecular profile, as well as the development of new treatments, allow new therapeutic options for these rare tumors. The efficiency of IDH1 inhibitors in other malignancies suggests that these inhibitors will be part of IDH1/2 mutated conventional CS management soon. Other treatment approaches, such as PIK3-AKT-mTOR inhibitors, cell cycle inhibitors, and epigenetic or immune modulators based on improving our understanding of CS molecular biology, are emerging.

Targeted treatment of solid tumors in pediatric precision oncology

The treatment of childhood solid cancer has markedly evolved in recent years following a refined molecular characterization and the introduction of novel targeted drugs. On one hand, larger sequencing studies have revealed a spectrum of mutations in pediatric tumors different from adults. On the other hand, specific mutations or immune dysregulated pathways have been targeted in preclinical and clinical studies, with heterogeneous results. Of note, the development of national platforms for tumor molecular profiling and, in less measure, for targeted treatment, has been essential in the process. However, many of the available molecules have been tested only in relapsed or refractory patients, and have proven poorly effective, at least in monotherapy. Our future approaches should certainly aim at improving the access to molecular characterization, to obtain a deeper picture of the distinctive phenotype of childhood cancer. In parallel, the implementation of access to novel drugs should not only be limited to basket or umbrella studies but also to larger, multi-drug international studies. In this paper we reviewed the molecular features and the main available therapeutic options in pediatric solid cancer, focusing on available targeted drugs and ongoing investigations, aiming at providing a useful tool to navigate the heterogeneity of this promising but complex field.

Positive response of a recurrent clear cell sarcoma to anlotinib combined with chemotherapy: A case report

RATIONALE

Renal clear cell sarcoma is a rare and highly invasive malignant renal tumor that easily relapses after treatment. Recurrent recurrent clear cell carcinoma (CCSK) responds poorly to chemotherapy and has no established standardized treatment, and need to be explored potentially useful treatments.

PATIENT CONCERNS

A 18-years-old patient with renal clear cell sarcoma recurrence after open radical nephrectomy.

DIAGNOSIS

Recurrent clear cell sarcoma.

INTERVENTIONS

After chemotherapy alone failed, the patient received 6 courses of anlotinib combined with chemotherapy. The tumor had significantly reduced in size and the recurrent tumor and part of the liver were resected.

OUTCOMES

No tumor recurrence or metastasis was detected during the follow-up 8 months after the operation.

LESSONS

This is the first report describing the use of anlotinib in treating CCSK. We believe that anlotinib combined with chemotherapy may be a useful treatment option for patients with recurrent CCSK.

Case report: Successful treatment with the combined therapy of interferon-alpha 2b and anlotinib in a patient with advanced hepatic epithelioid hemangioendothelioma

Hepatic epithelioid hemangioendothelioma (HEH) is a very rare tumor originating from vascular endothelial cells, with unpredictable malignancy. At present, there is no standard treatment protocol yet established. Both surgical resection and liver transplantation have been reported to be effective treatments for HEH; however, multiple intrahepatic lesions or extrahepatic metastasis make these procedures unsuitable to most patients. Systematic therapy has also been investigated, but the results are undetermined due to the limited cases. Interferon-alpha 2b (IFN-a 2b) has also been used for the treatment of HEH. Based on our previous study, the rate of tumor regression with IFN-a 2b monotherapy was more than 50%. Here, we reported a patient with advanced HEH, who achieved a partial response with the combined therapy of anlotinib and IFN-a 2b. The tumor stayed stable for 2 years with anlotinib monotherapy and regressed 3 months after the combined therapy of anlotinib and IFN-a 2b. The synergistic effect of combined therapy with anlotinib and IFN-a 2b provided promising guidance for future clinical study.

Receptor Tyrosine Kinase Inhibitors for the Treatment of Recurrent and Unresectable Bone Sarcomas

Bone sarcomas are a heterogeneous group of rare tumors with a predominance in the young population. Few options of systemic treatment are available once they become unresectable and resistant to conventional chemotherapy. A better knowledge of the key role that tyrosine kinase receptors (VEGFR, RET, MET, AXL, PDGFR, KIT, FGFR, IGF-1R) may play in the pathogenesis of these tumors has led to the development of multi-target inhibitors (TKIs) that are progressively being incorporated into our therapeutic arsenal. Osteosarcoma (OS) is the most frequent primary bone tumor and several TKIs have demonstrated clinical benefit in phase II clinical trials (cabozantinib, regorafenib, apatinib, sorafenib, and lenvatinib). Although the development of TKIs for other primary bone tumors is less advanced, preclinical data and early trials have begun to show their potential benefit in advanced Ewing sarcoma (ES) and rarer bone tumors (chondrosarcoma, chordoma, giant cell tumor of bone, and undifferentiated pleomorphic sarcoma). Previous reviews have mainly provided information on TKIs for OS and ES. We aim to summarize the existing knowledge regarding the use of TKIs in all bone sarcomas including the most recent studies as well as the potential synergistic effects of their combination with other systemic therapies.

Activity and safety of apatinib monotherapy or apatinib combined with chemotherapy for patients with metastatic or unresectable osteosarcoma over the age of 40 years: A retrospective analysis

BACKGROUND

Osteosarcoma commonly develops during childhood and adolescence. Only one-third of osteosarcoma patients have been clinically detected over the age of 40 years, and the survivorship of those patients is quite dismal. Apatinib, a novel multitarget angiogenesis inhibitor, has shown a short-term efficacy in advanced or metastatic osteosarcoma. However, the data for apatinib in the older patients with osteosarcoma are limited. We aim to evaluate the efficacy and safety of apatinib combined with chemotherapy versus apatinib monotherapy in the treatment of patients over 40 years old with metastatic or unresectable osteosarcoma.

METHODS

We retrospectively analyzed the patients with metastatic osteosarcoma who were treated with apatinib monotherapy or apatinib combined with chemotherapy between May 2015 and December 2018 in the Department of Orthopedics at West China Hospital. Apatinib was initially administered with a dose of 500 mg daily, and the dose was adjusted according to toxicity. The objective response rate (ORR), disease control rate (DCR), duration of response (DOR), progression-free survival (PFS), and overall survival (OS) were investigated. The treatment-related adverse events and the safety of apatinib were also documented.

RESULTS

A total of 45 patients (28 men, 17 women) with metastatic or unresectable osteosarcoma were finally included, and 41 patients received at least one cycle of treatment and were evaluable for efficacy. Of 41 patients, 24 who were intolerant to intensive chemotherapy or have failed standard chemotherapy received apatinib monotherapy, and 17 patients were treated with apatinib plus chemotherapy. The median PFS and median OS were longer in the group treated with apatinib combined with chemotherapy than those of the apatinib monotherapy group (5.6 months vs. 2.6 months; 15.1 months vs. 9.7 months). Moreover, the median DOR was significantly prolonged in the group treated with apatinib combined with chemotherapy compared with that in the monotherapy group.

CONCLUSION

Apatinib demonstrated promising activity in patients over 40 years old with metastatic or unresectable osteosarcoma. The combination of apatinib and chemotherapy conferred a durable response compared with apatinib monotherapy, which might be an alternative therapeutic strategy for the management of osteosarcoma in older patients.

Four-copy number alteration (CNA)-related lncRNA prognostic signature for liver cancer

The objective of this study was to identify CNA-related lncRNAs that can better evaluate the prognosis of patients with liver cancer. Prognostic molecular subtypes were identified, followed by tumor mutation and differential expression analyses. Genomic copy number anomalies and their association with lncRNAs were also evaluated. A risk model was built based on lncRNAs, as well as a nomogram, and the differences in the tumor immune microenvironment and drug sensitivity between the High_ and Low_risk groups were compared. Weighted gene co-expression network analysis was used to identify modules with significant enrichment in prognostic-related lncRNAs. In total, two subtypes were identified, TP53 and CTNNB1 were common high-frequency mutated genes in the two subtypes. A total of 8,372 differentially expressed (DE) mRNAs and 798 DElncRNAs were identified between cluster1 and cluster2. In addition, a four-lncRNA signature was constructed, and statistically significant differences between the Low_ and High_risk groups were found in terms of CD8 T cells, resting memory CD4 T cells, etc. Enrichment analysis showed that prognostic-related lncRNAs were involved in the cell cycle, p53 signaling pathway, non-alcoholic fatty liver disease, etc. A prognostic prediction signature, based on four-CNA-related lncRNAs, could contribute to a more accurate prognosis of patients with liver cancer.

Efficacy and Safety of Treating Refractory Bone and Soft Tissue Sarcoma with Anlotinib in Different Treatment Patterns

Methods

The medical data of 47 patients with refractory bone and soft tissue sarcoma, who received anlotinib from January 2019 to December 2020, were retrospectively collected. The overall response rate (ORR) and disease control rate (DCR) were evaluated according to the solid tumor response evaluation version 1.1 standard. The progression-free survival (PFS), overall survival (OS), and adverse reactions were recorded.

Results

A total of 44 patients, including 13 with osteosarcoma and 31 with soft tissue sarcoma, were enrolled in this study. Among patients with osteosarcoma, no patients achieved complete response (CR) or partial response (PR), while seven patients (54%) had stable disease (SD). Besides, the median PFS (m-PFS) was 4.4 months, and the median OS (m-OS) was 15.7 months. Among patients with soft tissue sarcoma, the ORR and DCR were 19% and 71%, respectively. The median m-PFS was 5.4 months, and m-OS was 17.9 months. Anlotinib plus chemotherapy had a higher ORR compared with anlotinib monotherapy (6% vs. 38%, P = 0.047). The most common grade 3/4 adverse reactions were pneumothorax (5%) and pleural effusion (5%), and no treatment-related deaths occurred.

Conclusions

Anlotinib alone showed encouraging efficacy and favorable tolerability in refractory bone and soft tissue sarcoma. Anlotinib plus chemotherapy did not show a significant clinical benefit compared with anlotinib alone. Anlotinib showed better tumor control when used as first-line drug treatment in refractory bone and soft tissue sarcoma.

Management of Unresectable Localized Pelvic Bone Sarcomas: Current Practice and Future Perspectives

Simple Summary

Some locally advanced pelvic bone tumors are deemed unresectable and, as such, not suitable for curative surgery. In this setting, treatment options are generally limited and not unanimous, with decisions being made on an individual basis after multidisciplinary discussion. Ultimately, and notwithstanding the bright prospects raised by novel therapeutic approaches, treatment should be patient-tailored, weighing a panoply of patient- and tumor-related factors.

Abstract

Bone sarcomas (BS) are rare mesenchymal tumors usually located in the extremities and pelvis. While surgical resection is the cornerstone of curative treatment, some locally advanced tumors are deemed unresectable and hence not suitable for curative intent. This is often true for pelvic sarcoma due to anatomic complexity and proximity to vital structures, making treatment options for these tumors generally limited and not unanimous, with decisions being made on an individual basis after multidisciplinary discussion. Several studies have been published in recent years focusing on innovative treatment options for patients with locally advanced sarcoma not amenable to local surgery. The present article reviews the evidence regarding the treatment of patients with locally advanced and unresectable pelvic BS, with the goal of providing an overview of treatment options for the main BS histologic subtypes involving this anatomic area and exploring future therapeutic perspectives. The management of unresectable localized pelvic BS represents a major challenge and is hampered by the lack of comprehensive and standardized guidelines. As such, the optimal treatment needs to be individually tailored, weighing a panoply of patient- and tumor-related factors. Despite the bright prospects raised by novel therapeutic approaches, the role of each treatment option in the therapeutic armamentarium of these patients requires solid clinical evidence before becoming fully established.

Efficacy and safety of anlotinib in patients with unresectable or metastatic bone sarcoma: A retrospective multiple institution study

Background

Tyrosine kinase inhibitors (TKIs) such as cabozantinib, regorafenib have demonstrated encouraging activity in prolonging progression‐free survival (PFS) in several bone sarcoma entities in prospective clinical trials. This retrospective study aims to analyze the safety and efficacy of anlotinib, a novel multi‐target TKI, in patients with locally unresectable or metastatic bone sarcoma at three institutions.

Methods

Patients with advanced bone sarcoma administered anlotinib 12 mg once daily, 2 weeks on/1 week off, from June 2018 to June 2020, until disease progression or intolerance of treatment. The primary endpoints were objective response rate (ORR) and PFS.

Results

Forty‐eight patients were analyzed: 27 have osteosarcoma, 9 have chondrosarcoma, 8 have Ewing's sarcoma, and 3 have chordoma. The median age was 24 years (range, 16–68 years), and the median number of prior regimens was 1 (range, 0–4). Until the final follow‐up, five patients obtained a partial response and while 24 achieved stable disease. The ORR in all patients was 10.4%, and the median PFS was 4.6 months, with a progression‐free rate (PFR) at 3 months and 6 months of 72.9% and 35.4%, respectively. The ORR and median PFS varied much among tumor subtypes. The most frequent grade 3–4 adverse events (AEs) were pneumothorax, hand‐foot syndrome, cholesterol elevation, hypertriglyceridemia, and fatigue. No patients died from anlotinib‐related AEs during the study period.

Conclusions

Anlotinib may show promising antitumor activity in unresectable or metastatic bone sarcoma. The ORR and median PFS of anlotnib are similar to those of other targeted drugs in different subtypes of sarcomas. The AEs were generally mild and tolerated well. Further studies of anlotinib in selected subtypes of bone sarcoma are needed.