Bone and Soft Tissue Sarcoma

Effect of palliative radiation dose on symptom response in metastatic sarcomas

Purpose

Palliative radiotherapy (RT) plays a crucial role in alleviating symptoms associated with metastatic sarcoma. However, there is a lack of consensus on the optimal palliative radiation dose and fractionation for metastatic sarcomas. We analyzed the association between biologically effective radiation dose and symptom response for patients who underwent palliative RT for metastatic sarcomas.

Methods and materials

We retrospectively identified patients with metastatic sarcoma treated with palliative RT between 1999 and 2021 at our institution. We assessed the association between equivalent dose in 2 Gy fractions (EQD2) with an α/β of three and symptom relief or overall survival (OS) using univariable and multivariable analyses.

Results

Of the 198 metastatic sites treated, the most common indications for palliative radiation were pain (n = 181, 91 %) and compression of adjacent structures (n = 16, 8 %). In our analysis, an EQD2 of > 20 Gy was associated with greater rates of short-term symptom relief (n = 143, 85 %) at the RT site compared to an EQD2 of ≤ 20 Gy (n = 14, 54 %, P = 0.001) with no reports of grade 3 or higher toxicity. However, there was no significant improvement in short-term symptom relief for higher radiation doses. Patients treated with an EQD2 of ≤ 20 Gy had a significantly worse performance status, but there was no significant difference in overall survival based on EQD2 on multivariable analysis.

Conclusions

An EQD2 ≤ 20 Gy (e.g., 8 Gy in 1 fraction) provided inadequate palliative benefit in this series. An EQD2 > 20 Gy resulted in greater rates of symptom palliation in metastatic sarcomas, but further dose escalation did not improve symptom response or durability. These findings suggest standard palliative regimens such as 20 Gy in 5 fractions (EQD2 of 28 Gy) are effective for patients with metastatic sarcomas.

Application of Indocyanine Green Fluorescence Imaging in Assisting Biopsy of Musculoskeletal Tumors

(1) Background: Biopsies are the gold standard for the diagnosis of musculoskeletal tumors. In this study, we aimed to explore whether indocyanine green near-infrared fluorescence imaging can assist in the biopsy of bone and soft tissue tumors and improve the success rate of biopsy. (2) Method: We recruited patients with clinically considered bone and soft tissue tumors and planned biopsies. In the test group, indocyanine green (0.3 mg/kg) was injected. After identifying the lesion, a near-infrared fluorescence camera system was used to verify the ex vivo specimens of the biopsy in real time. If the biopsy specimens were not developed, we assumed that we failed to acquire lesions, so the needle track and needle position were adjusted for the supplementary biopsy, and then real-time imaging was performed again. Finally, we conducted a pathological examination. In the control group, normal biopsy was performed. (3) Results: The total diagnosis rate of musculoskeletal tumors in the test group was 94.92% (56/59) and that in the control group was 82.36% (42/51). In the test group, 14 cases were not developed, as seen from real-time fluorescence in the core biopsy, and then underwent the supplementary biopsy after changing the puncture direction and the location of the needle channel immediately, of which 7 cases showed new fluorescence. (4) Conclusions: Using the near-infrared fluorescence real-time development technique to assist the biopsy of musculoskeletal tumors may improve the accuracy of core biopsy and help to avoid missed diagnoses, especially for some selected tumors.

Issues of diagnostic search of soft tissue sarcoma

Relevance. Soft tissue sarcoma is a heterogeneous group of relatively rare types of tumors, which demonstrates a huge variety of anatomical localization and histopathological characteristics. The rarity of soft tissue sarcomas combined with a variety of subtypes, forms of growth, progression and frequency of relapses makes it difficult to study them, make a correct diagnosis and early referral of patients for specialized care.

The purpose of study. To analyze the problem of differential diagnosis of malignant and benign soft tissue neoplasms.

Materials and methods. In the course of the work, current literary sources of domestic and foreign authors on a given topic were analyzed.

Results. Since it is absolutely impossible to determine the clinical features of the presented sarcoma, soft tissue tumors showing any of the following signs are considered malignant until the opposite is proven: increasing in size, >5 cm, deeply located and/or painful. The greater the number of these clinical signs present, the higher the risk that the soft tissue tumor will turn out to be malignant; at the same time, an increase in size is the best individual indicator. It is worth noting that the absence of concomitant constitutional symptoms, such as fever, chills, night sweats or unintentional weight loss, should not reduce the doctor's suspicion of malignancy.

Conclusion. In order to avoid erroneous diagnoses, a standardized diagnostic approach should be followed, starting from the moment of collecting the patient's medical history, clinical examination and ending with the use of appropriate imaging methods and biopsy.

Issues of diagnostic search of soft tissue sarcoma

Relevance. Soft tissue sarcoma is a heterogeneous group of relatively rare types of tumors, which demonstrates a huge variety of anatomical localization and histopathological characteristics. The rarity of soft tissue sarcomas combined with a variety of subtypes, forms of growth, progression and frequency of relapses makes it difficult to study them, make a correct diagnosis and early referral of patients for specialized care.

The purpose of study. To analyze the problem of differential diagnosis of malignant and benign soft tissue neoplasms.

Materials and methods. In the course of the work, current literary sources of domestic and foreign authors on a given topic were analyzed.

Results. Since it is absolutely impossible to determine the clinical features of the presented sarcoma, soft tissue tumors showing any of the following signs are considered malignant until the opposite is proven: increasing in size, >5 cm, deeply located and/or painful. The greater the number of these clinical signs present, the higher the risk that the soft tissue tumor will turn out to be malignant; at the same time, an increase in size is the best individual indicator. It is worth noting that the absence of concomitant constitutional symptoms, such as fever, chills, night sweats or unintentional weight loss, should not reduce the doctor's suspicion of malignancy.

Conclusion. In order to avoid erroneous diagnoses, a standardized diagnostic approach should be followed, starting from the moment of collecting the patient's medical history, clinical examination and ending with the use of appropriate imaging methods and biopsy.

Nanoparticle albumin-bound paclitaxel and PD-1 inhibitor (sintilimab) combination therapy for soft tissue sarcoma: a retrospective study

Background

There is increasing evidence that combination therapy with nanoparticle albumin-bound paclitaxel (nab-paclitaxel) and programmed cell death protein 1 (PD-1) inhibitor is safe and efficacious in treating many types of malignant tumors. However, clinical data demonstrating the effect of this treatment combination for patients with metastatic soft tissue sarcoma (STS) are currently limited.

Methods

The clinical data of patients with metastatic STS who received nab-paclitaxel plus PD-1 inhibitor (sintilimab) therapy between January 2019 and February 2021 were retrospectively analyzed. The effectiveness and safety of the combined treatment were evaluated in terms of the median progression-free survival (PFS), estimated using the Kaplan–Meier method. The univariate Cox proportional hazards model was used to analyze the relationship between clinicopathological parameters and PFS. All statistical analyses were two-sided; P < 0.05 was considered statistically significant.

Results

A total of 28 patients treated with nab-paclitaxel plus sintilimab were enrolled in this study. The objective response rate was 25%, the disease control rate was 50%, and the median PFS was 2.25 months (95% CI = 1.8–3.0 months). The most common grade 1 or 2 adverse events (AEs) were alopecia (89.3%; 25/28), leukopenia (25.0%; 7/28), fatigue (21.4%; 6/28), anemia (21.4%; 6/28), and nausea (21.4%; 6/28). The most common grade 3 AEs were neutropenia (10.7%; 3/28) and peripheral neuropathy (10.7%; 3/28). No grade 4 AEs were observed. Among the present study cohort, patients with angiosarcoma (n = 5) had significantly longer PFS (P = 0.012) than patients with other pathological subtypes, including undifferentiated pleomorphic sarcoma (n = 7), epithelioid sarcoma (n = 5), fibrosarcoma (n = 4), synovial sarcoma (n = 3), leiomyosarcoma (n = 2), pleomorphic liposarcoma (n = 1), and rhabdomyosarcoma (n = 1); those who experienced three or more AEs had significantly longer median PFS than those who experienced less than three AEs (P = 0.018).

Conclusion

Nab-paclitaxel plus PD-1 inhibitor is a promising treatment regimen for advanced STS. Randomized controlled clinical trials are required to further demonstrate its efficacy and optimal application scenario.