Japanese Orthopaedic Association (JOA) clinical practice guidelines on the management of soft tissue tumors 2020 - Secondary publication

Histological diagnostic discrepancy and its clinical impact in bone and soft tissue tumors referred to a sarcoma center

Histological diagnosis of sarcomas (malignant bone and soft tissue tumors) is challenging due to their rarity, morphological diversity, and constantly evolving diagnostic criteria. In this study, we aimed to assess the concordance in histological diagnosis of bone and soft tissue tumors between referring hospitals and a tertiary sarcoma center and analyzed the clinical impact of the diagnostic alteration. We analyzed 628 consecutively accessioned specimens from 624 patients who visited a specialized sarcoma center for treatment. The diagnoses at referring hospitals and those at the sarcoma center were compared and classified into four categories: agreed, disagreed, specified, and de-specified. Of the 628 specimens, the diagnoses agreed in 403 (64.2%) specimens, whereas some changes were made in 225 (35.8%) specimens: disagreed in 153 (24.3%), specified in 52 (8.3%), and de-specified in 20 (3.2%) cases. The benign/intermediate/malignant judgment changed for 92 cases (14.6%). The diagnostic change resulted in patient management modification in 91 cases (14.5%), including surgical and medical treatment changes. The main inferred reason for the diagnostic discrepancies was a different interpretation of morphological findings of the tumor, which accounted for 48.9% of the cases. This was followed by the unavailability of specialized immunohistochemical antibodies and the unavailability of genetic analysis. In summary, our study clarified the actual clinical impact of diagnostic discrepancy in bone and soft tissue tumors. This may underscore the value of pathology consultation, facilitating access to specialized diagnostic tools, and continued education. These measures are expected to improve diagnostic precision and ultimately benefit patients.

Primary prophylaxis with G-CSF for patients with non-round cell soft tissue sarcomas: a systematic review for the Clinical Practice Guidelines for the Use of G-CSF 2022 of the Japan Society of Clinical Oncology

BACKGROUND

Granulocyte colony-stimulating factor (G-CSF) is an essential supportive agent for chemotherapy-induced severe myelosuppression. We proposed two clinical questions (CQ): CQ #1, "Does primary prophylaxis with G-CSF benefit chemotherapy for non-round cell soft tissue sarcoma (NRC-STS)?" and CQ #2, "Does G-CSF-based intensified chemotherapy improve NRC-STS treatment outcomes?" for the Clinical Practice Guidelines for the Use of G-CSF 2022 of the Japan Society of Clinical Oncology.

METHODS

A literature search was performed on the primary prophylactic use of G-CSF for NRC-STSs. Two reviewers assessed the extracted papers and analyzed overall survival, incidence of febrile neutropenia, infection-related mortality, quality of life, and pain.

RESULTS

Eighty-one and 154 articles were extracted from the literature search for CQs #1 and #2, respectively. After the first and second screening, one and two articles were included in the final evaluation, respectively. Only some studies have addressed these two clinical questions through a literature review.

CONCLUSION

The clinical questions were converted to future research questions because of insufficient available data. The statements were proposed: "The benefit of primary G-CSF prophylaxis is not clear in NRC-STS" and "The benefit of intensified chemotherapy with primary G-CSF prophylaxis is not clear in NRC-STSs." G-CSF is often administered as primary prophylaxis when chemotherapy with severe myelosuppression is administered. However, its effectiveness and safety are yet to be scientifically proven.

Radiation therapy improves survival in elderly patients with localized extremity soft tissue sarcoma

BACKGROUND

This study aims to evaluate the efficacy of radiation therapy in enhancing survival outcomes among elderly patients diagnosed with localized extremity soft tissue sarcomas (STSs). Furthermore, it seeks to explore whether the survival benefits conferred by radiation therapy differ according to tumor characteristics and treatment modalities.

METHODS

We conducted a retrospective analysis using the Surveillance, Epidemiology, and End Results (SEER) database to identify patients aged 80 years and older diagnosed with localized extremity STSs. The study assessed 1498 eligible patients, analyzing cancer-specific survival (CSS) and overall survival (OS) through Kaplan-Meier survival analysis and Cox proportional hazards modeling. Propensity score matching was employed to adjust for potential confounders.

RESULTS

Among the analyzed patients, 773 patients underwent radiation therapy (Radiation group), while 725 patients either did not receive radiation therapy or it was unknown if they had (No-Radiation group). The 5-year OS rate was 40% in the radiation group compared to 38% in the no-radiation group. After propensity score matching, radiation therapy was associated with a significant improvement in OS (P = 0.005, HR = 0.8, 95% CI 0.7-0.9). Subgroup analyses indicated that patients undergoing primary tumor resection benefited most from radiation therapy in terms of OS.

CONCLUSION

Radiation therapy is associated with improved overall survival in elderly patients with localized extremity STSs. These findings suggest that radiation therapy should be considered as a key component of the treatment strategy for this patient population, taking into account individual patient characteristics and comorbidities.

Factors associated with survival in patients with clear cell sarcoma

Aims

Clear cell sarcoma (CCS) of soft-tissue is a rare melanocytic subtype of mesenchymal malignancy. The aim of this study was to investigate the clinical and therapeutic factors associated with increased survival, stratified by clinical stage, in order to determine the optimal treatment.

Methods

The study was a retrospective analysis involving 117 patients with histologically confirmed CCS, between July 2016 and November 2017, who were enrolled in the Bone and Soft Tissue Tumour Registry in Japan.

Results

The five- and ten-year survival rates were 41% (95% confidence interval (CI) 29 to 52) and 37% (95% CI 25 to 49), respectively. On multivariable analysis, the size of the tumour of > 10 cm (p = 0.006), lymph node metastasis at the time of diagnosis (p < 0.001), distant metastases at the time of diagnosis (p < 0.001), and no surgery for the primary tumour (p = 0.019) were independently associated with a poor survival. For N0M0 CCS (n = 68), the development of distant metastases was an independent prognostic factor for survival (early (< 12 months), hazard ratio (HR) 116.78 (95% CI 11.69 to 1,166.50); p < 0.001; late (> 12 months), HR 14.79 (95% CI 1.66 to 131.63); p = 0.016); neoadjuvant/adjuvant chemotherapy (p = 0.895) and/or radiotherapy (p = 0.216) were not significantly associated with survival. The five-year cumulative incidence of local recurrence was 19% (95% CI 8 to 35) and the size of the tumour was significantly associated with an increased rate of local recurrence (p = 0.012). For N1M0 CCS (n = 18), the risk of mortality was significantly lower in patients who underwent surgery for both the primary tumour and lymph node metastases (HR 0.03 (95% CI 0.00 to 0.56); p = 0.020). For M1 CCS (n = 31), excision of the primary tumour was independently associated with better survival (HR 0.26 (95% CI 0.09 to 0.76); p = 0.013). There was no significant difference in survival between the different types of systemic treatment (p = 0.523).

Conclusion

Complete excision of the primary tumour and lymph nodes is associated with a better survival in patients with CCS. Systemic treatment appears to provide limited benefits, demonstrating a pressing need for novel systemic agents.

Calcified deep somatic soft tissue leiomyoma of the leg: A case report

Deep somatic soft tissue leiomyoma is a rare benign smooth muscle tumor, with around 60 cases reported thus far in the literature. Herein, we report a huge leiomyoma in deep somatic soft tissue with massive calcification in the peroneus longus muscle. A 29-year-old male patient presented with a hard, spindle-shaped, 15-cm-diameter mass of the left lower leg. Plain radiography showed marked calcification within the lesion, and magnetic resonance imaging revealed a well-circumscribed lesion with strong contrast enhancement within the peroneus longus. A core needle biopsy was performed to rule out a soft tissue sarcoma, and deep somatic soft tissue leiomyoma was preoperatively diagnosed. A marginal excision was performed, and the patient recovered without event and has been recurrence-free for 16 months. As far as we know, the present soft tissue leiomyoma was one of the largest to be documented, the previously reported cases being up to 14 cm in maximum diameter. Leiomyomas of deep somatic soft tissue should be included in the differential diagnosis of a huge, deep-seated tumor with marked calcification as well as sarcomas, especially in younger patients.

Anti-Tumor Effect and Neurotoxicity of Ethanol Adjuvant Therapy after Surgery of a Soft Tissue Sarcoma

Wide resection is the main treatment for sarcomas; however, when they are located near major nerves, their sacrifices might affect limb function. The efficacy of ethanol adjuvant therapy for sarcomas has not been established. In this study, the anti-tumor effect of ethanol, as well as its neurotoxicity, were assessed. In vitro anti-tumor effect of ethanol as evaluated using MTT, wound healing, and invasion assays on a synovial sarcoma cell line (HS-SY-II). In vivo, an assessment was conducted in nude mice (implanted with subcutaneous HS-SY-II) treated with different ethanol concentrations after surgery with a close margin. Sciatic nerve neurotoxicity was assessed with electrophysiological and histological examination. In vitro, ethanol concentrations at 30% and higher showed cytotoxic effects in MTT assay and markedly reduced migration and invasive ability of HS-SY-II. In vivo, both 30% and 99.5% ethanol concentrations, compared to 0% concentration, significantly reduced the local recurrence. However, in the group treated with 99.5% ethanol, nerve conduction tests showed prolonged latency and decreased amplitude, and morphological changes suggestive of nerve degeneration were observed in the sciatic nerve, while the 30% ethanol did not cause neurological damage. In conclusion, 30% is the optimal concentration for ethanol adjuvant therapy after close-margin surgery for sarcoma.

Myxoinflammatory Fibroblastic Sarcoma of the Hand

Myxoinflammatory fibroblastic sarcoma is an ultra-rare tumor type with a prevalence of fewer than two per 100,000 people. The tumor poses a challenge because it can be misdiagnosed as a benign lesion in clinical and radiological investigations, causing serious morbidity in patients. We present the case of a 33-year-old patient who presented with painless hand swelling that was misdiagnosed as lymphaticovenous malformation based on magnetic resonance imaging. The patient underwent surgical excision, and myxoinflammatory fibroblastic sarcoma was diagnosed postoperatively. All surgical interventions failed to achieve negative margin. A decision to start radiotherapy was made, and tissue convergence was done temporally using acellular dermal matrix and split-thickness skin graft. On patient follow-up, the graft had taken well, and the patient was undergoing radiotherapy sessions with a plan for permanent hand reconstruction after negative margins are achieved. Based on this case report, we identified that magnetic resonance imaging is not yet a reliable method to diagnose myxoinflammatory fibroblastic sarcoma. Therefore, implementing a multidisciplinary team approach, a preoperative core needle biopsy, planned surgical intervention, and early involvement of radiotherapy is recommended to minimize morbidity. We strongly urge establishing a sarcoma specialized treatment center in the region to limit patient morbidity.

Review of the referral documents of patients with malignant soft tissue tumors

Fifteen years have passed since the soft tissue tumor practice guidelines were first published in Japan. Tumor size of ≥ 5 cm and tumor depth were key findings suggestive of malignant soft tissue tumors. We reviewed the referral documents provided by the referring physicians to see if these two findings were reported. The study was conducted from January 2007 to December 2021 and included 142 patients (83 men and 59 women; median age, 64 [6-94] years) with malignant soft tissue tumors. Patient referral documents from physicians were screened for descriptions of the tumor size and depth. The tumor size, depth, and both were described in 51.4%, 36.6%, and 23.2% of the referrals, respectively. Both findings were mentioned in 23.8%, 21.7%, and 25.0% of referrals in 2007-2011, 2012-2016, and 2017-2021, respectively. Of orthopedic surgeons and other physicians, 61.2% and 38.6%, respectively, described the tumor size. Whether the general physicians could follow the soft tissue tumor practice guidelines was difficult to conclude by reviewing patient referral documents. However, orthopedic surgeons seemed to pay more attention to tumor size. Awareness regarding soft tissue tumor practice guidelines should be increased to help diagnose malignant soft tissue tumors early.

Management of elderly patients with bone and soft tissue sarcomas: JCOG Bone and Soft Tissue Tumor Study Group

Approximately, 40% of bone sarcomas and 60% of soft tissue sarcoma arise in patients aged ≥65 years. However, because sarcoma is very rare, there is little evidence regarding the management of elderly patients with sarcoma. Age has been reported as a prognostic factor in patients with sarcomas. The standard therapy for all localized bone and soft tissue sarcomas is surgical resection, even in elderly patients. Radiation or ion-beam therapy can be considered for unresectable sarcomas. Although adjuvant chemotherapy is standard for osteosarcoma, the usefulness of adjuvant chemotherapy for elderly patients has not been verified; therefore, it may not be recommended for elderly patients with osteosarcoma. For elderly patients with advanced osteosarcoma, if general conditions permit, doxorubicin- and/or ifosfamide-based regimens as well as molecular-targeted therapies, including sorafenib, regorafenib and everolimus, may be considered, although these drugs have not been approved for sarcoma in Japan. Adjuvant chemotherapy with doxorubicin plus ifosfamide is recommended for patients with high-risk localized soft tissue sarcoma if they are aged ≤70 years. For first-line treatment of advanced soft tissue sarcoma in elderly patients, doxorubicin monotherapy is considered to be the standard regimen, and pazopanib can be an alternative. For second-line treatment, gemcitabine-based regimens, pazopanib, trabectedin and eribulin may be options for elderly patients with advanced soft tissue sarcoma.