Epidemiological characteristics of 1385 primary sacral tumors in one institution in China

Is 3D-printed self-stabilizing endoprosthesis reconstruction without supplemental fixation following total sacrectomy a viable approach for sacral tumours?

PURPOSE

The spinopelvic reconstruction poses significant challenges following total sacrectomy in patients with malignant or aggressive benign bone tumours encompassing the entire sacrum. In this study, we aim to assess the functional outcomes and complications of an integrated 3D-printed sacral endoprostheses featuring a self-stabilizing design, eliminating the requirement for supplemental fixation.

METHODS

We retrospectively analyzed patients with sacral tumours who underwent total sacrectomy followed by reconstruction with 3D-printed self-stabilizing endoprosthesis. Clinically, we evaluated functional outcomes using the 1993 version of the musculoskeletal tumour society (MSTS-93) score. Perioperative and postoperative complications were also documented.

RESULTS

10 patients met final inclusion criteria. The median age was 49 years (range, 31-64 years). The median follow-up time was 26.5 months (range, 15-47 months). Median postoperative functional MSTS-93 was 22.5 (range, 13-25). The median operation time was 399.5 min (305-576 min), and the median intraoperative blood loss was and 3200 ml (2400-7800 ml). Complications include wound dehiscence in one patient, bowel, bladder, and sexual dysfunction in four patients, cerebrospinal fluid leak in one patient, and tumour recurrence in one patient. There were no mechanical complications related to the endoprosthesis at the last follow-up.

CONCLUSION

The utilization of 3D-printed self-stabilizing endoprosthesis proved to be a viable approach, yielding satisfactory short-term outcomes in patients undergoing total sacral reconstruction without supplemental fixation.

Enhanced recovery after surgery (ERAS) in sacral tumour surgery and comprehensive description of a multidisciplinary program: a prospective study in a specialized hospital in China

PURPOSE

There were fewer data to guide the application of enhanced recovery after surgery (ERAS) theory into sacral tumour surgery. In the present study, we were aiming to describe a multidisciplinary program of ERAS and evaluate the availability in sacral tumour surgery.

METHODS

This was a prospective study of patients with sacral tumour between March 2021 and September 2021 at a single centre. We proposed a multidisciplinary program of ERAS for pre-admission, preoperative, intraoperative, postoperative, and post-discharge clinical care which positively influenced outcomes of patients with sacral tumour. All patients were prospectively assigned into two groups, ERAS group in which patients received ERAS protocols (n = 63), No-ERAS group in which patients had conventional clinical pathways (n = 62). Patient data were collected which included demographics, preoperative preparation, detailed information of surgical procedure, 60-day reoperation rate, 60-day readmission, postoperative length of stay (PLOS), time to first ambulation and flatus after surgery, time to removal of last drainage tube, and visual analogue scale (VAS) score at first ambulation and discharge. Complications referred to ones that occurred within 60 days after surgery. The above parameters were compared between ERAS group and No-ERAS group.

RESULTS

Time to first ambulation after surgery in ERAS group (mean 20.9 h) was significantly shorter than that in No-ERAS group (mean 104.3 ho). Meanwhile, time to first flatus after surgery in ERAS group (mean 26.7 h) was also significantly shorter than that in No-ERAS group (mean 37.3 h). Patients in ERAS group had statistically shorter PLOS (10.7 days) as compared to that in No-ERAS group (13.8 days). In ERAS group, 19 of 63 patients (30.2%) were discharged within seven days after surgery as compared to seven of 62 patients (11.3%) in No-ERAS group. VAS score at first ambulation in ERAS group was not obviously higher than that in No-ERAS group though the time of first ambulation in ERAS group was statistically earlier than one in No-ERAS group. Furthermore, VAS score at discharge in ERAS group was significantly lower than that in No-ERAS group. The rate of postoperative incision necrosis was 6.3% (4/63) in ERAS group and 8.1% (5/62) in No-ERAS group and all of these nine patients underwent reoperation before discharge. The difference was not statistically significant in the wound complication of incision necrosis and 60-day reoperation rate. Only one readmission occurred in No-ERAS group due to the surgical site infection and also there was no significant difference of 60-day readmission rate between these two groups. Furthermore, there was no statistical difference of complications of femoral artery thrombosis and rectal rupture between ERAS group and No-ERAS group.

CONCLUSIONS

Our proposed ERAS pathway for sacral tumour surgery and early walking facilitate safe and prompt discharge. ERAS protocols of sacral tumour surgery could decrease PLOS without significantly increasing postoperative complications, 60-day readmission rate and 60-day reoperation rate. The application of ERAS pathway in the field of sacral tumour surgery should have personalized feature with regard to resection type.

A machine learning-based model for clinical prediction of distal metastasis in chondrosarcoma: a multicenter, retrospective study

Background

The occurrence of distant metastases (DM) limits the overall survival (OS) of patients with chondrosarcoma (CS). Early diagnosis and treatment of CS remains a great challenge in clinical practice. The aim of this study was to investigate metastatic factors and develop a risk stratification model for clinicians' decision-making.

Methods

Six machine learning (ML) algorithms, including logistic regression (LR), plain Bayesian classifier (NBC), decision tree (DT), random forest (RF), gradient boosting machine (GBM) and extreme gradient boosting (XGBoost). A 10-fold cross-validation was performed for each model separately, multicenter data was used as external validation, and the best (highest AUC) model was selected to build the network calculator.

Results

A total of 1,385 patients met the inclusion criteria, including 82 (5.9%) patients with metastatic CS. Multivariate logistic regression analysis showed that the risk of DM was significantly higher in patients with higher pathologic grades, T-stage, N-stage, and non-left primary lesions, as well as those who did not receive surgery and chemotherapy. The AUC of the six ML algorithms for predicting DM ranged from 0.911-0.985, with the extreme gradient enhancement algorithm (XGBoost) having the highest AUC. Therefore, we used the XGB model and uploaded the results to an online risk calculator for estimating DM risk.

Conclusions

In this study, combined with adequate SEER case database and external validation with data from multicenter institutions in different geographic regions, we confirmed that CS, T, N, laterality, and grading of surgery and chemotherapy were independent risk factors for DM. Based on the easily available clinical risk factors, machine learning algorithms built the XGB model that predicts the best outcome for DM. An online risk calculator helps simplify the patient assessment process and provides decision guidance for precision medicine and long-term cancer surveillance, which contributes to the interpretability of the model.

METTL3-mediated m6A modification of circRNF220 modulates miR-330-5p/survivin axis to promote osteosarcoma progression

BACKGROUND

Circular RNAs (circRNAs) play a crucial role in regulating various physiological processes. However, the precise regulatory mechanisms of circRNF220s in osteosarcoma (OS) are not well understood.

METHODS

The abundances of circRNF220, miR-330-5p, and survivin were determined using qRT-PCR. To assess the m6A accumulation in circRNF220, a methylated RNA immunoprecipitation (Me-RIP) assay was conducted. Cellular multiplication, motility, and invasion were examined using the cell Counting Kit-8 (CCK-8), EdU, colony formation, Transwell, and wound-healing assays. The binding relationships were measured through RNA immunoprecipitation (RIP) and luciferase reporter assays. In vivo functionality was assessed using xenograft models.

RESULTS

CircRNF220 was identified as being overexpressed in both OS cells and tissues. In vitro experiments demonstrated that silencing circRNF220 impeded the proliferation, invasion, and motility of OS cells. Similarly, in vivo studies confirmed that downregulating circRNF220 inhibited the growth of OS. Further mechanistic investigations unveiled that METTL3-modulated circRNF220 regulated the progression of OS by upregulating survivin expression through acting as a sponge for miR-330-5p.

CONCLUSION

The modulation of METTL3-regulated circRNF220 has been found to promote the progression of OS by modulating the miR-330-5p/survivin axis. This novel finding suggests a potentially unique approach to managing OS.

Deep-Learning-Based Model for the Prediction of Cancer-Specific Survival in Patients with Spinal Chordoma

OBJECTIVE

Spinal chordomas are locally aggressive and frequently recurrent tumors with a poor prognosis. Previous studies focused on a Cox regression model to predict the survival of patients with spinal chordoma. We aimed to develop a more effective model based on deep learning for prognosis prediction in spinal chordoma.

METHODS

Patients with spinal chordoma were gathered from the SEER database. Cox regression analysis was conducted to compare the influence of different clinical characteristics on cancer-specific survival. Two deep learning models, namely, DeepSurv and NMTLR, were developed, alongside 2 classic models, for the purpose of comparison. Performance of these models was evaluated by concordance index, Integrated Brier Score, receiver operating characteristic curves, Kaplan-Meier curves, and calibration curves.

RESULTS

A total of 258 spinal chordoma patients were included in the current study. The median follow-up time was 94 ± 52 months. Variables used for prognosis prediction consisted of age, primary site, tumor size, histologic grade, extension of surgery, tumor invasion, and metastasis. Comparing with conventional models, each deep learning model showed superior predictive performance, the C-index on the test cohort is 0.830 for DeepSurv and 0.804 for NMTLR, respectively. The DeepSurv model represented the best performance, with area under the curve of 0.843 in predicting 5-year survival and 0.880 in predicting 10-year survival.

CONCLUSIONS

We successfully constructed a deep learning model to predict the CSS of spinal chordoma patients and proved that it was more accurate and practical than conventional prediction model. Our deep learning model has the potential to guide clinicians in better care planning and decision-making.

Role of Apparent Diffusion Coefficient Map-Based First- and High-Order Radiomic Features for the Discrimination of Sacral Chordomas and Chondrosarcomas With Overlapping Conventional Imaging Features

PURPOSE

Chondrosarcomas arise from the lateral pelvis; however, midline chondrosarcomas (10%) display similar imaging features to chordoma, causing a diagnostic challenge. This study aims to determine the diagnostic accuracy of apparent diffusion coefficient (ADC)-based radiomic features and two novel diffusion indices for differentiating sacral chordomas and chondrosarcomas.

METHODS

A retrospective, multireader review was performed of 82 pelvic MRIs (42 chordomas and 40 chondrosarcomas) between December 2014 and September 2021, split into training (n = 69) and validation (n = 13) data sets. Lesions were segmented on a single slice from ADC maps. Eight first-order features (minimum, mean, median, and maximum ADC, standard deviation, skewness, kurtosis, and entropy) and two novel indices: restriction index (RI, proportion of lesions with restricted diffusion) and facilitation index (FI, proportion of lesions with facilitated diffusion) were estimated. One hundred seven radiomic features comparing patients with chondrosarcoma versus chordoma were sorted based on mean group differences.

RESULTS

There was good to excellent interobserver reliability for eight of the 10 ADC metrics on the training data set. Significant differences were observed (P < .005) for RI, FI, median, mean, and skewness using the training data set. Optimal cutpoints for diagnosis of chordoma were RI > 0.015; FI < 0.25; mean ADC < 1.7 × 10-3 mm2/s; and skewness >0.177. The optimal decision tree relied on FI. In a secondary analysis, significant differences (P < .00047) in chondrosarcoma versus chordoma were found in 18 of 107 radiomic features, including six first-order and 12 high-order features.

CONCLUSION

The novel ADC index, FI, in addition to ADC mean, skewness, and 12 high-order radiomic features, could help differentiate sacral chordomas from chondrosarcomas.

Silencing circUSP48 suppresses osteosarcoma progression by regulating the miR-335/ smad nuclear interacting protein 1 pathway

BACKGROUND

Circular RNAs (circRNAs) can have a critical function in the multi-processes of osteosarcoma (OS). Nevertheless, whether circUSP48 is involved in OS progression remains unclear.

METHODS

In the current work, the expression of circUSP48, miR-335 and SNIP1 in OS cell lines and tissues were evaluated using qRT-PCR. Then, Sanger sequencing, RNase R treatment and FISH assay were performed for circUSP48 validation. Furthermore, the function and potential mechanisms of circUSP48 in OS were investigated by performing loss-of-function experiments.

RESULTS

Silencing circUSP48 could suppress proliferation, invasion as well as migration of OS cells in vitro, also inhibiting the growth of tumor in vivo. Importantly, circUSP48 promoted OS malignancy by sponging miR-335 to upregulate SNIP1.

CONCLUSION

Overall, these findings suggested that circUSP48 acted as an oncogene in OS, which might become a new target for OS therapy.

Management of Chordoma of the Sacrum and Mobile Spine

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Chordomas account for 1% to 4% of primary tumors of the spine and sacrum.

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En bloc resection is the preferred surgical treatment for the management of chordomas.

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Proton beam radiation is increasingly being used as a postoperative radiation modality for the treatment of chordomas.

The management of sacral tumours

Tumours of the sacrum are difficult to manage. The sacrum provides the structural connection between the torso and lower half of the body and is subject to both axial and rotational forces. Thus, tumours or their treatment can compromise the stability of the spinopelvic junction. Additionally, nerves responsible for lower limb motor groups as well as bowel, bladder, and sexual function traverse or abut the sacrum. Preservation or sacrifice of these nerves in the treatment of sacral tumours has profound implications on the function and quality of life of the patient. This annotation will discuss current treatment protocols for sacral tumours.

Cite this article: Bone Joint J 2022;104-B(12):1284–1291.

Imaging Diagnosis of Primary Solitary Bone Neoplasts and Its Comparison with Tumor-like Lesions

Objective. To explore the imaging diagnostic value of primary solitary bone tumor and tumor-like lesion of iliac crest. Methods. A total of 156 patients with primary solitary bone tumors and tumor-like lesions of the iliac bone treated in our hospital were selected, and the patients were diagnosed by X-ray, CT, and MRI. Sexual analysis of single diagnostic and combined diagnostic value was carried out. Results. Round high-density shadow, soft tissue mass shadow, soft tissue mass, right intestinal tube, and bladder obvious pressure were observed. The detection rates of giant cell tumor of bone, myeloma, osteochondroma, chondroma, eosinophilic granuloma, osteosarcoma, fibrous dysplasia, and Hodgkin lymphoma were 34.6%, 12.8%, 11.5%, 10.3%, 7.7%, 6.4%, 3.8%, and 2.6%, and the differences were statistically significant (P < 005); X-ray, CT, MR single diagnostic comparison, three methods joint diagnostic missed diagnosis rate and misdiagnosis rate, higher detection rate ( $P<0.05$ ); combined with X-ray, CT, MR single diagnosis, three methods joint diagnosis sensitivity, specificity, accuracy, statistical significance ( $P<0.05$ ); comparison with X-ray, CT, MR single diagnosis, three methods jointly diagnosed positive predictive value, negative predictive value higher, difference statistics significance ( $P<0.05$ ); there is a significant difference in the near-end, backbone, and distal detection rate of different bone tumors and tumor lesions, including the humerus and tibia. There is a statistical significance of the detection rate, and the difference is $P<0.05$ . Conclusion. X-ray plays an important role in the diagnosis of primary solitary bone tumor and tumor-like lesion of iliac crest and is the first choice in clinical diagnosis. In the diagnosis of tumor disease, range, and soft tissue mass, MRI and CT diagnostic value can provide effective theoretical basis for patient clinical treatment. Therefore, the appropriate diagnostic method should be selected according to the specific situation of the patient, so that the efficiency of the clinical feature is improved.

A Case Report of Rare Sacral Solitary Fibrous Tumor

Huge primary epidural solitary fibrous tumors in the sacrum are a rare clinical entity. The purpose of this article is to present our experience in treating such large and complex neoplasms in a 31-year-old woman. The patient complained of constant nocturnal bilateral hip and lower back pain and unilateral radicular symptoms (numbness, paresthesias) in the left S1/S2 dermatomal distribution. Diagnostic imaging, biopsy, preoperative endovascular embolization, two-staged tumor resection, and lumbosacroiliac fusion were performed. The treatment resolved the patient’s neurological symptoms and resulted in overall good postoperative functionality. The patient has been in remission for more than five years despite her refusal of adjuvant radiotherapy.

Silencing long non-coding RNA LINC00960 inhibits osteosarcoma proliferation by sponging miR-107 to downregulate SALL4

long non-coding RNAs (lncRNAs), as tumor suppressors or oncogenes, have been identified to play key roles in tumorigenesis. The present study explored the roles and potential mechanisms of LINC00960 in osteosarcoma (OS). In vitro study showed that silencing LINC00960 inhibited proliferation, migration and invasion of 143B and MG63. In vivo study demonstrated that knockdown of LINC00960 repressed tumor growth. Further investigation revealed that LINC00960 could regulate SALL4 by sponging miR-107 to promote the progression of OS. Together, LINC00960 is a tumor oncogene in the development and prognosis of OS, which may be a new therapeutic target for OS.

Multidisciplinary Management of Primary Sacral Tumors: A Tertiary Care Center's Experience and Literature Review

Sacral tumors are rare and can be benign or malignant. Their management is multifactorial and is based on the pathology, extent, and local and distant spread. Managing sacral tumors is challenging due to their proximity to visceral and neural structures. Surgical wide excision has been the standard of care for aggressive benign and malignant tumors. Our purpose was to evaluate the outcomes of a multimodal approach to managing primary sacral tumors in Sakra World Hospital, a tertiary spine care center in Bengaluru, India and perform a literature review to determine a workflow pathway. Our study was a retrospective review of patient records and included 15 patients with primary sacral tumors. Eleven surgically treated patients were evaluated clinically and radiologically and underwent biopsy before surgical excision by an all-posterior approach. A multidisciplinary approach that included intraoperative neural monitoring, plastic reconstruction, adjuvant chemotherapy, and radiotherapy was implemented whenever necessary. Sacral root preservation was attempted whenever feasible. Functional outcomes (based on the Visual Analog Scale [VAS] and Biagini scoring system) were analyzed along with disease control, with a minimum of 2 years of follow-up. The mean follow-up was 29±9.8 months. The mean VAS score significantly improved from 7.8±2.6 to 3.7±3.8 (p=0.026). Bowel function showed statistically significant improvement, from a mean score of 0.81±0.47 to 0.63±0.52 (p=0.026) at 2 years of follow-up. The mean pretreatment motor and bladder function scores were 0.53±0.31 and 0.74±0.44, respectively, improving to 0.48±0.33 and 0.68±0.56 at follow-up but without statistical significance. There was no significant loss of function, which is expected in radical sacral resections. In conclusion, primary sacral tumors require a multidisciplinary approach and management for optimal outcomes. A stand-alone posterior approach can be employed to treat most sacral lesions. En-bloc wide resection is the optimal treatment for primary malignant and aggressive benign tumors. Preservation of at least one functional S2 nerve root is imperative to preserve bowel and bladder function.

Nerve preservation during partial sacrectomy by two-stage anterior and posterior approach: illustrative case

BACKGROUND

Preserving the neurological function of sacral nerves during total or partial sacrectomy is challenging.

OBSERVATIONS

The authors describe a case of an osseous desmoplastic fibroma of the sacrum in a 51-year-old woman. The patient attended the authors’ institution with loss of muscle strength and sensitivity impairment in both legs, gait instability, bowel constipation, urinary incontinence, and weight loss. Preoperative magnetic resonance imaging and positron emission tomography/computed tomography showed intrapelvic and posterior extension of the tumor but sparing of S1 and the sacroiliac and lumbosacral joints. After a multidisciplinary discussion of the case, a staged anterior–posterior approach to the sacrum was chosen. The abdominal approach allowed full mobilization of the uterus, ovaries, bladder, and colon and protection of iliac vessels. After tumor resection, a synthetic surgical mesh was placed over the sacrum to minimize soft tissue defects. Then, the posterior stage allowed the authors to perform a bicortical osteotomy, achieving wide tumor excision with minimal nerve root injury. Spinopelvic fixation was not necessary, because both sacroiliac and lumbosacral joints remained intact. A few days after the surgery, the patient restarted ambulation and recovered sphincter control.

LESSONS

Multidisciplinary planning and a staged abdominal and posterior approach for partial sacrectomy were fundamental to preserve neurological function in this case.

Primary sacral non-Hodgkin's lymphoma: report of a case and systematic review of literature

INTRODUCTION

Isolated primary sacral diffuse large B cell non-Hodgkin's lymphoma is a very rare entity, and only 11 cases have been reported previously.

CASE PRESENTATION

A 36-year-old man was referred with low backache and radiculopathy pain with a clinico-radiological and cytological diagnosis of sacral metastasis. Histopathological examination and immunohistochemistry of image-guided tissue core biopsy from the sacral mass confirmed it as high-grade diffuse large B cell lymphoma (DLBCL). With normal blood counts and bone marrow, and no lesions elsewhere on imaging, he was staged IAE and received 6 cycles of R-CHOP (rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisolone) regimen chemotherapy followed by radiotherapy. The patient has completed a 3-year follow-up and is doing well with yearly imaging showing no evidence of active disease or recurrence.

CONCLUSIONS

The case shows the importance of an image-guided core biopsy and immunohistochemistry over a fine needle aspiration cytology in select cases as it can alter the treatment and outcome in patients. Because of rarity, the treatment and prognosis in primary sacral NHL is not still very clear as it is treated as per the guidelines of treatment of bone lymphoma.