Critical study of resection margins in adult soft-tissue sarcoma surgery

Buried de-epithelialized flap: An original solution to fill dead space after sarcoma resection in the thigh. Surgical technique and results of 12 cases

INTRODUCTION

Soft tissue sarcomas (STS) are often treated with wide excision in combination with adjuvant or neoadjuvant radiotherapy. This is currently the gold standard procedure for the treatment of STS that arise in the extremities. Wound healing complications frequently occur and negatively affect the prognosis. One of the options is to use a buried de-epithelialized flap as it can increase the lymphatic flow, fill the dead space, and cover neurovascular structures and implants. This aim of this retrospective study were two-fold. 1) Describe the surgical technique for this buried de-epithelialized flap after STS removal in the thigh. 2)Evaluate the efficacy of the buried de-epithelialized flap for decreasing wound complications based on a small case series and compare it with previous publications.

HYPOTHESIS

We hypothesized that the complication rate of this flap is not higher than the published complication rate for traditional flaps.

MATERIALS AND METHODS

Twelve patients (7 women and 5 men) with a mean age of 62±12years (38-76), who underwent surgical removal of an STS in the thigh with coverage by a buried de-epithelialized flap were reviewed at a mean follow-up of 15.8months (range 8-24).

RESULTS

Two patients presented with a postoperative wound infection (17%): one superficial and one deep at the surgical site. Neither required an additional plastic surgery procedure. Another patient had a dislocation of their total hip arthroplasty that was managed by closed reduction. One patient died from metastatic progression. There was no skin necrosis of the superficial skin edges, no hematoma or seroma in the other 10 patients. The flap was still visible on cross-sectional imaging at 1 month postoperative with no fluid between the tissue planes or signs of necrosis. The rate of wound healing complications that required surgical treatment was 17% in our case series, versus 16 to 56% in previous publications reporting the results of suture closure only.

CONCLUSION

A buried de-epithelialized flap reduces the risk of skin complications by filling dead space, improving lymphatic flow and covering critical structures. It is a reliable and reproducible option after wide local excision of STS in the thigh, with no additional morbidity.

LEVEL OF EVIDENCE

IV, retrospective study.

Surgical Margins in Musculoskeletal Sarcoma

» Negative margin resection of musculoskeletal sarcomas is associated with reduced risk of local recurrence.» There is limited evidence to support an absolute margin width of soft tissue or bone that correlates with reduced risk of local recurrence.» Factors intrinsic to the tumor, including histologic subtype, grade, growth pattern and neurovascular involvement impact margin status and local recurrence, and should be considered when evaluating a patient's individual risk after positive margins.» Appropriate use of adjuvant therapy, critical analysis of preoperative advanced cross-sectional imaging, and the involvement of a multidisciplinary team are essential to obtain negative margins when resecting sarcomas.

Naturally occurring canine sarcomas: Bridging the gap from mouse models to human patients through cross-disciplinary research partnerships

Fueled by support from the National Cancer Institute's "Cancer Moonshot" program, the past few years have witnessed a renewed interest in the canine spontaneous cancer model as an invaluable resource in translational oncology research. Increasingly, there is awareness that pet dogs with cancer provide an accessible bridge to improving the efficiency of cancer drug discovery and clinical therapeutic development. Canine tumors share many biological, genetic, and histologic features with their human tumor counterparts, and most importantly, retain the complexities of naturally occurring drug resistance, metastasis, and tumor-host immune interactions, all of which are difficult to recapitulate in induced or genetically engineered murine tumor models. The utility of canine models has been particularly apparent in sarcoma research, where the increased incidence of sarcomas in dogs as compared to people has facilitated comparative research resulting in treatment advances benefitting both species. Although there is an increasing awareness of the advantages in using spontaneous canine sarcoma models for research, these models remain underutilized, in part due to a lack of more permanent institutional and cross-institutional infrastructure to support partnerships between veterinary and human clinician-scientists. In this review, we provide an updated overview of historical and current applications of spontaneously occurring canine tumor models in sarcoma research, with particular attention to knowledge gaps, limitations, and growth opportunities within these applications. Furthermore, we propose considerations for working within existing veterinary translational and comparative oncology research infrastructures to maximize the benefit of partnerships between veterinary and human biomedical researchers within and across institutions to improve the utility and application of spontaneous canine sarcomas in translational oncology research.

Evaluating the relevance of surgical margins. Part one: The problems with current methodology

The goal of cancer surgery is to achieve a "clean" microscopic resection, with no residual tumour remaining in the wound. To achieve that goal, the surgeon typically incorporates a measured buffer of grossly normal tissue about the entire circumference of the tumour. Microscopic analysis of the resection boundaries is then performed to determine if all traces of the tumour have been completely removed. This analysis is thought to provide a surrogate indication as to the likelihood for that tumour to recur after surgery. However, it is recognised that tumour recurrence may not occur even when microscopic evidence of tumour has been identified at the resection margins, and recurrence can also occur when conventional histology has considered the tumour to have been completely removed. The explanations for this dichotomy are numerous and include technical and practical limitations of the processing methodology, and also several surgeon-related and tumour-related reasons. Ultimately, the inability to confidently determine when a tumour has been removed sufficiently to prevent recurrence can impact on the ability to provide owners with confident treatment advice. In this article, the authors describe the challenges with defining the true extent of the tumour margin from the perspective of the surgeon, the pathologist and the tumour. The authors also provide an analysis of why our current efforts to ensure that all traces of the local tumour have been successfully removed may provide an imperfect assessment of the risk of recurrence.

Defining the relevance of surgical margins. Part two: Strategies to improve prediction of recurrence risk

Due to the complex nature of tumour biology and the integration between host tissues and molecular processes of the tumour cells, a continued reliance on the status of the microscopic cellular margin should not remain our only determinant of the success of a curative-intent surgery for patients with cancer. Based on current evidence, relying on a purely cellular focus to provide a binary indication of treatment success can provide an incomplete interpretation of potential outcome. A more holistic analysis of the cancer margin may be required. If we are to move ahead from our current situation - and allow treatment plans to be more intelligently tailored to meet the requirements of each individual tumour - we need to improve our utilisation of techniques that either improve recognition of residual tumour cells within the surgical field or enable a more comprehensive interrogation of tumour biology that identifies a risk of recurrence. In the second article in this series on defining the relevance of surgical margins, the authors discuss possible alternative strategies for margin assessment and evaluation in the canine and feline cancer patient. These strategies include considering adoption of the residual tumour classification scheme; intra-operative imaging systems including fluorescence-guided surgery, optical coherence tomography and Raman spectroscopy; molecular analysis and whole transcriptome analysis of tissues; and the development of a biologic index (nomogram). These techniques may allow evaluation of individual tumour biology and the status of the resection margin in ways that are different to our current techniques. Ultimately, these techniques seek to better define the risk of tumour recurrence following surgery and provide the surgeon and patient with more confidence in margin assessment.

Overall survival in patients with re-excision of positive microscopic margins of limb and trunk wall soft tissue sarcoma operated outside of a reference center: a nationwide cohort analysis

Background

This French nationwide NETSARC exhaustive prospective cohort aims to explore the impact of systematic re-excision (RE) as adjuvant care on overall survival (OS), local recurrence free survival (LRFS), and local and distant control (RFS) in patients with soft tissue sarcoma (STS) with positive microscopic margins (R1) after initial resection performed outside of a reference center.

Methods

Eligible patients had experienced STS surgery outside a reference center from 2010 to 2017, and had R1 margins after initial surgery. Characteristics and treatment comparisons used chi-square for categorical variables and Kruskall-Wallis test for continuous data. Survival distributions were compared in patients reexcised (RE) or not (No-RE) using a log-rank test. A Cox proportional hazard model was used for subgroup analysis.

Results

A total of 1,284 patients had experienced initial STS surgery outside NETSARC with R1 margins, including 1,029 patients with second operation documented. Among the latter, 698 patients experienced re-excision, and 331 were not re-excised. Characteristics were significantly different regarding patient age, tumor site, tumor size, tumor depth, and histotype in the population of patients re-excised (RE) or not (No-RE). The study identified RE as an independent favorable factor for OS (HR 0.36, 95%CI 0.23–0.56, p<0.0001), for LRFS (HR 0.45, 95%CI 0.36–0.56, p<0.0001), and for RFS (HR 0.35, 95%CI 0.26–0.46, p<0.0001).

Conclusion

This large nationwide series shows that RE improved overall survival in patients with STS of extremities and trunk wall, with prior R1 resection performed outside of a reference center. RE as part of adjuvant care should be systematically considered.

Level of evidence II

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-022-10121-5.

Factors associated with complications after resection of soft tissue sarcomas of the groin

INTRODUCTION

Soft tissue sarcomas (STS) are rare malignant tumors that require regimented treatment at designated cancer centers. The surgical care of groin tumors is difficult because of frequent local complications. Few studies have been done on prognostic factors and complications. This led us to conduct a retrospective study to: (1) identify factors associated with local postoperative complications during the surgical care of primary groin STS; (2) identify the factors associated with delayed adjuvant radiation therapy; (3) define the optimal surgical treatment strategy to allow adjuvant treatments to start as early as possible, if applicable.

HYPOTHESIS

We hypothesized that certain patients presenting with an STS of the groin or inguinal area are at higher risk of complications.

MATERIALS AND METHODS

This retrospective single-center study included all the patients admitted to our referral sarcoma center between 1995 and 2016 for the resection of a primary STS of the groin. Major complications were defined as surgical revision, an invasive procedure, or prolonged dressing use.

RESULTS

Of the 55 included patients, 13 suffered major complications (24%) of which 10 were surgical revisions, two were repeated aspirations and one was prolonged dressing use. Among the 10 surgical revisions, there were two pedicled salvage flaps. The patients who suffered major complications were significantly more likely to be smokers than the patients who did not have major complications (31% vs 2% (p=0.002)). Obesity and surgical bone exposure were most often associated with complications but not significantly (23% vs 5%, p=0.053 and 38% vs 14% (p=0.057), respectively). Of the 39 patients (71%) who needed postoperative radiation therapy, 5 patients (13%) had it delayed, and 3 patients (8%) did not receive any at all due to major complications.

CONCLUSION

In our study, smoking was associated with the occurrence of major complications after groin STS resection and there was a strong trend for obesity and surgical bone exposure. Major complications were associated with a delay in starting postoperative radiation therapy. Thus, we recommend flap coverage after tumor resection in patients who have factors known to contribute to complications.

LEVEL OF EVIDENCE

IV, Retrospective study.

Adult Soft-Tissue Sarcomas of the Extremities

➤

Soft-tissue sarcomas (STS) in adults comprise a heterogeneous group of tumors of mesenchymal origin that share similar biological patterns of local tumor growth and metastatic dissemination.

➤

The judicious use of imaging studies, biopsy techniques, and pathological evaluations is essential for accurate diagnosis and for planning treatment strategy.

➤

Wide local resection and radiation therapy form the cornerstone of management of high-grade STS. The role of adjuvant radiation therapy is questionable in the management of small (≤5 cm) superficial lesions that can be resected with negative margins. Chemotherapy given to patients who have nonmetastatic, high-grade STS results in varying benefit in terms of local tumor control and overall survival.

➤

Coordinated care by a multidisciplinary team of trained surgeons, medical oncologists, radiologists, radiation oncologists, and pathologists has been documented to improve local tumor control and the overall survival of patients with STS.

➤

Although considerable progress in tumor diagnostics and targeted therapies has been made over the past 2 decades, recommendations and controversies relating to tumor imaging and margins of resection have not changed.

Management of adipose tumors in the limbs

Adipose tumors of the limbs are the most common soft tissue lesions and are essentially benign (lipomas). However, in some cases, they can be considered as tumors with intermediate malignancy (atypical lipomatous tumor [ALT]) or sarcoma lineage (liposarcoma [LS]). The essential work-up for a potential adipose tumor consists of a clinical examination and initial ultrasound imaging to determine the size (more or less than 5 cm), the location (over or under the fascia) and any potential atypical vascularization. As needed, MRI will complete the assessment and validate the ultrasound results and confirm the fatty nature of the lesion. Percutaneous biopsy will be done when a deep fatty lesion is larger than 5 cm (long axis), with detection by amplification of the MDM2 gene that guides the diagnosis towards ALT or dedifferentiated LS. Superficial lesions without atypia are not challenging from a surgical point of view. However, large ALT can be more difficult to manage. Their local malignancy does not justify sacrificing any critical structures. As for true LS, their treatment is well defined, with tumor excision addressed at a center belonging to the Network of Sarcomas Reference Centers in France (NETSARC+) and for potential (neo)adjuvant treatment if needed. Inappropriate treatment of a malignant tumor can have serious consequences (loss of chance to survive or to be cured) for the patient. Furthermore, treatment at a specialized cancer center has been proven to be effective as it improves overall survival and reduces local recurrences.

Greater travel distance to specialized facilities is associated with higher survival for patients with soft-tissue sarcoma: US nationwide patterns

Purpose

The survival impact of geographic access to specialized care remains unknown in patients with soft-tissue sarcomas (STS). This study aimed to clarify the association between the patient travel distance and survival outcome and investigate the factors lying behind it.

Methods

A total of 34 528 patients with STS registered in the National Cancer Data Base, diagnosed from 2004–2016, were investigated.

Results

Tumor stage correlated with travel distance: patients with metastatic disease stayed closer to home. However, the type of facility showed greatest variation: 37.0%, 51.0%, 73.5%, and 75.9% of patients with ≤10 miles, 10.1–50 miles, 50.1–100 miles, and >100 miles, respectively (P<0.001), had a sarcoma care at academic/research centers. On a multivariable analysis, reduced mortality risk was associated with longer (versus short) travel distance (>100 miles: HR = 0.877; P = 0.001) and management at academic/research (versus non-academic/research) centers (HR = 0.857; P<0.001). The greatest divergence was seen in patients traveling very long distance (>100 miles) to an academic/research center, with a 26.9% survival benefit (HR = 0.731; P<0.001), compared with those traveling short distance (≤10 miles; 95.4% living in metropolitan area) to a non-academic/research center. There was no significant correlation between travel distance and survival in patients who had care at academic/research centers, whereas a survival benefit of management at academic/research centers was observed in every group of travel distance, regardless of tumor stage.

Conclusions

This national study demonstrated that increased travel distance was associated with superior survival, attributable to a higher proportion of patients receiving sarcoma care at distant academic/research centers. These data support centralized care for STS. Overcoming referral and travel barriers may enable more patients to be treated at specialized centers and may further improve survival rates for patients with STS, even when it imposes an increased travel burden.

Margin Assessment in Soft Tissue Sarcomas: Review of the Literature

Simple Summary

Many classifications to assess margins status for soft tissue sarcomas are reported in the literature. Most of the series are heterogeneous and variable in size, making it difficult to compare results from study to study. Thus, which is the best way to assess margins in order to predict the risk of local recurrence is still debated. The aim of this narrative review is to provide a comprehensive assessment of the literature on margins, and to highlight the need for a uniform description of the margin status for patients with soft tissue sarcomas (STS).

Abstract

Adequacy of margins must take into consideration both the resection margin width (quantity) and anatomic barrier (quality). There are several classification schemes for reporting surgical resection margin status for soft tissue sarcomas (STS). Most of the studies regarding treatment outcomes in STS included all histologic grades and histological subtypes, which include infiltrative and non-infiltrative subtypes and are very heterogeneous in terms of both histologic characteristics and treatment modalities (adjuvant treatments or not). This lack of consistency makes it difficult to compare results from study to study. Therefore, there is a great need for evidence-based standardization concerning the width of resection margins. The aim of this narrative review is to provide a comprehensive assessment of the literature on margins, and to highlight the need for a uniform description of the margin status for patients with STS. Patient cases should be discussed at multidisciplinary tumor boards and treatments should be individualized to clinical and demographic characteristics, which must include also a deep knowledge of specific histotypes behaviors, particularly infiltrative ones.

The Effect of Resection Margin on Local Recurrence and Survival in High Grade Soft Tissue Sarcoma of the Extremities: How Far Is Far Enough?

Simple Summary

In soft tissue sarcomas the width of surgical margins after resection determines the extent of surgery and the function after resection. But how far is really necessary? 305 patients with deep-seated, G2/3 soft tissue sarcomas of the extremity, the trunk wall, or the pelvis were reviewed. The 5-year local recurrence-free survival (LRFS) was 82%. Overall survival (OS) at 5 years was 66%. Positive (contaminated) margins worsened LRFS and OS. A margin of >10 mm did not improve LRFS and OS as compared to one of >5 mm. A resection margin of <1 mm showed a trend but not significantly better LRFS or OS compared to a contaminated margin. In conclusion the margin should at least be free of tumor, in sound tissue. A margin of >5 mm sound tissue seems to be sufficient. Resecting more tissue does not benefit the patient.

Abstract

Background: The significance of surgical margins after resection of soft tissue sarcomas in respect to local-recurrence-free survival and overall survival is evaluated. Methods: A total of 305 patients with deep-seated, G2/3 soft tissue sarcomas (STS) of the extremity, the trunk wall, or the pelvis were reviewed. The margin was defined according to the Fédération Nationale des Centres de Lutte Contre le Cancer (FNCLCC) classification system (R0-2), the Union Internationale Contre le Cancer (UICC) classification (R + 1 mm) for which a margin <1 mm is included into the R1 group, and in groups of <1 mm, 1–5 mm, >5 mm, or >10 mm. Results: Of these patients, 31 (10.2%) had a contaminated margin, 64 (21%) a margin of <1 mm, 123 (40.3%) a margin of 1–5 mm, 47 (15.4%) a margin of >5 mm, and 40 (13.1%) a margin of >10 mm. The 5-year local recurrence-free survival (LRFS) was 81.6%. Overall survival (OS) at 5 years was 65.9%. Positive margins worsened LRFS and OS. A margin of >10 mm did not improve LRFS and OS as compared to one of >5 mm. Conclusions: A resection margin of <1 mm showed a trend but not significantly better LRFS or OS compared to a contaminated margin. This finding supports use of the UICC classification. A margin of more than 10 mm did not improve LRFS or OS.

Deep Functional and Molecular Characterization of a High-Risk Undifferentiated Pleomorphic Sarcoma

Nonrhabdomyosarcoma soft-tissue sarcomas (STSs) are a class of 50+ cancers arising in muscle and soft tissues of children, adolescents, and adults. Rarity of each subtype often precludes subtype-specific preclinical research, leaving many STS patients with limited treatment options should frontline therapy be insufficient. When clinical options are exhausted, personalized therapy assignment approaches may help direct patient care. Here, we report the results of an adult female STS patient with relapsed undifferentiated pleomorphic sarcoma (UPS) who self-drove exploration of a wide array of personalized Clinical Laboratory Improvement Amendments (CLIAs) level and research-level diagnostics, including state of the art genomic, proteomic, ex vivo live cell chemosensitivity testing, a patient-derived xenograft model, and immunoscoring. Her therapeutic choices were also diverse, including neoadjuvant chemotherapy, radiation therapy, and surgeries. Adjuvant and recurrence strategies included off-label and natural medicines, several immunotherapies, and N-of-1 approaches. Identified treatment options, especially those validated during the in vivo study, were not introduced into the course of clinical treatment but did provide plausible treatment regimens based on FDA-approved clinical agents.

A technical note to prevent superficial tumor cell dissemination at fungating soft tissue tumor resection

Dissemination of the tumor within surgical field increases the risk of local recurrences. Fungating soft tissue tumors present a special risk of contamination in the attempt to perform wide resections. We hypothesized that adequate tumor coverage at resection could prevent tumor spilling and superficial dissemination in the operation field. For this purpose we used swabs to soak secretions. Incise drapes were put over swabs to seal the tumor. Double row skin staples were placed at the edge of the adhesive drapes for lift-off-prevention. We present eight patients treated with wide resection (3 myxofibrosarcomas, 2 malignant melanomas, 1 spindle cell sarcoma, 1 basal cell carcinoma, and 1 exulcerated lipoma). No complications were observed using this technique. An intraoperative local control, confirmed histologically, was achieved in all patients. Tumor covering could help local tumor control at fungating tumor resection.

Assessment of resection margins in bone sarcoma treated by neoadjuvant chemotherapy: Literature review and guidelines of the bone group (GROUPOS) of the French sarcoma group and bone tumor study group (GSF-GETO/RESOS)

BACKGROUND

Standardized reports are essential to meeting the bone sarcoma reference center certification requirements of the French National Cancer Institute (INCa). The usual classifications of the Musculoskeletal Tumor Society (MSTS), the American Joint Committee on Cancer (AJCC/IUCC) TNM R classification and the American College of Pathologists, are inexact inasmuch as they fail to include chemotherapy impact on tumor cells in assessing surgical margins. This leads to inconsistent interpretation by teams managing bone sarcoma. The present literature analysis sought to assess the limitations of existing classifications for purposes of standardized reporting of the management of surgical specimens from patients with osteosarcoma or Ewing sarcoma receiving neoadjuvant chemotherapy, by addressing the following questions: 1) What is the prognostic value of margins and chemotherapy response in the classifications? 2) What are the histologic changes induced by chemotherapy, with what impact on interpretation of margins?

METHOD

A PubMed literature analysis was performed, targeting the prognostic value of resection margin assessment, in September 2018. French bone pathology group (Groupe français des pathologistes osseux) and international guidelines on bone specimen management were referred to so as select items for a standardized report. Eight of the 523 articles retrieved met the study eligibility criteria.

RESULTS

Minimal distance between tumor and surgical margin, with a>2mm threshold, seemed to be the optimal parameter for predicting local recurrence. Good chemotherapy response and appendicular skeletal location were associated with lower risk of local recurrence. None of the available classifications take into account the microscopic changes induced by chemotherapy in interpreting resection margins.

DISCUSSION

To standardize practice, GROUPOS developed a standardized report for bone sarcoma specimens, considering the histopathologic changes in the tumor after neoadjuvant chemotherapy. The TNM R system was adapted and a threshold of>2mm was chosen as an acceptable limit to qualify surgical resection as safe (R0). R1 status (≤2mm) was subdivided into subgroups a, b and c, to include margin measurement in relation to the post-chemotherapy scar: R1a, resection within the scar; R1b, resection in healthy tissue,≤2mm from the scar and/or residual viable cells; and R1c, resection within the lesion in contact with viable cells or within coagulation necrosis areas. The GROUPOS members drew up this standardized report so as to ensure a common language, improving bone sarcoma management in specialized centers. Reliable data can thus be established for national and international multicenter studies.

LEVEL OF EVIDENCE

IV.

Soft tissue leiomyosarcoma-diagnostics, management, and prognosis: Data of the registry cancer of the center of Tunisia

Background:

Soft tissue leiomyosarcomas are rare, accounting for almost 5%–10% of all soft tissue sarcomas; they account for almost 1% of all sarcomas. They are aggressive tumors where location, size, and management require a multidisciplinary approach. Since there are few series published, we here analyze epidemiological pattern, clinical and pathologic features of soft tissue leiomyosarcomas.

Methods:

We conducted a retrospective study of 29 consecutive cases of histologically proven soft tissue leiomyosarcoma extracted from the database of the Cancer Registry of the Center of Tunisia and the Department of Pathology of Farhat Hached University Hospital of Sousse of Tunisia, during a 10-year period (from January 1996 to December 2005). Epidemiologic details, clinico-pathological features, and treatment modalities were assessed with focus on patients’ 5-year overall survival, tumor relapse, and metastases.

Results:

Soft tissue leiomyosarcoma accounted for 17.5% of all soft tissue sarcomas diagnosed at our pathology department. Most of patients were of advanced age (median: 52 years), with extremes ranging from 12 and 87 years. There was a slight male predominance (sex-ratio = 1.07). Tumors were located mostly in the lower limbs (45%). Deep sites as retroperitoneum was found only in two cases. Tumor size was more than 5 cm in 83% of cases (average size = 9.4 cm). Five cases had metastasis on initial staging. For 24 patients, the disease was locally limited at the moment of diagnosis. Palliative chemotherapy was indicated for four patients and surgery was performed for 20 patients. Local recurrence occurred in 11 patients (55% of operated patients) and metastasis in 6 patients. Overall, 5-year survival was about 24%.

Conclusion:

Our study results highlight the scarcity of soft tissue leiomyosarcoma. Unfortunately, unusual tumor sites, disease’s advanced stages, and intralesional resection made the prognosis poorer than in other series. Clinical course of soft tissue leiomyosarcoma was highly marked by local recurrence and metastasis.

Soft tissue sarcoma: adding diffusion-weighted imaging improves MR imaging evaluation of tumor margin infiltration

PURPOSE

To determine the added value of diffusion-weighted imaging (DWI) to conventional magnetic resonance (MR) imaging in assessment of tumor margin infiltration in soft tissue sarcoma (STS) at 3T.

MATERIALS AND METHODS

The institutional review board approved this retrospective study. Forty-five patients who underwent 3T MR imaging including DWI and were pathologically confirmed were included in this study. Two readers retrospectively scored conventional MR imaging alone. Then, they assessed a combination of conventional MR imaging and DWI. At pathology, margin infiltration was retrospectively reviewed by one pathologist blinded to MR findings. Areas under the curve (AUCs) of the receiver-operating characteristic curve were obtained for diagnostic performance. Interobserver agreement for the scoring of margin infiltration of STS was assessed with kappa statistics.

RESULTS

Among 45 cases of STS, 33 had infiltrative tumor margin at pathology. Sensitivity, specificity, and accuracy of each reader were 100%, 17%, and 78%; 97%, 25%, and 78% on conventional MR imaging alone and 94%, 67%, and 87%; 94%, 42%, and 80% on conventional MR imaging combined with DWI. AUCs of conventional MR imaging combined with DWI were significantly higher than those of conventional MR imaging alone: 0.890 vs 0.678 (p = .0123) and 0.846 vs 0.640 (p = .0305) for each reader. Interobserver agreements of conventional MR imaging alone and conventional MR imaging combined with DWI were moderate to substantial (κ = 0.646, κ = 0.496).

CONCLUSION

The addition of DWI to conventional MR imaging may improve specificity for assessing tumor margin infiltration in STS at 3T.

KEY POINTS

• DWI has added value for assessment of tumor margin infiltration in soft tissue sarcoma. • Addition of DWI to conventional MRI at 3T may improve specificity. • Addition of DWI to conventional MRI may help orthopedic surgeon determine the extent of the resection margin.

Management of soft tissue tumors of the musculoskeletal system

A palpable mass in the musculoskeletal system is a common reason for consultation. The main issue is that a malignant tumor must not be missed. Inappropriate initial treatment can have direct consequences on the risk of local recurrence, the patient's future function and life expectancy. A mass more than 5cm in diameter, a subfascial location and a recent increase in size are signs that should lead the physician to question whether the lesion is truly benign and to carry out diagnostic examinations. MRI is the gold standard imaging exam. Biopsy, which is now mainly percutaneous and imaging-guided, must be performed for any subfascial mass more than 5cm long or a smaller mass with a high risk of postoperative functional sequelae. Referring the patient to a specialized cancer center has direct benefits on the patient's recurrence-free survival and reduces time lost during the diagnostic and treatment phases. For malignant tumors, surgical treatment requires resection margins that comply with cancer guidelines. Preservation of the limb and its function may require multidisciplinary reconstruction techniques. Pre- or post-operative radiation therapy or chemotherapy should be proposed only after discussion in a multidisciplinary team meeting.

Canine Soft Tissue Sarcomas: Can Being a Dog's Best Friend Help a Child?

Soft tissue sarcomas (STSs) remain a therapeutic challenge for pediatric and adolescent and young adult (AYA) patients. Still today, surgery, radiation therapy, and chemotherapy remain the mainstay of treatment. Obstacles in developing new treatment approaches to improve the outcome are: few patients to enroll in clinical trials, and the diversity of tumor biology between histologic subtypes. Pet dogs may offer an additional strategy to discover and test new therapeutic avenues. The number of dogs diagnosed with a STS each year in the United States is estimated to be around 27,000 to 95,000. In comparison, approximately 900 children less than 20 years old and 1,500 AYAs between 15 and 29 years old are diagnosed with a STS each year in the United States. The mainstay for treatment of STSs in dogs is also surgery, with radiation therapy and chemotherapy when necessary. Similar to what is seen in humans, grade and stage are prognostic in dogs. In one comparative study of the histology and immunohistochemistry of canine STSs, most tumors were diagnosed as the human equivalent of undifferentiated sarcoma, spindle cell sarcoma, or unclassified spindle cell sarcoma. But much work remains to be done to fully assess the validity of canine STSs as a model. Gene expression analysis has been done in a limited number of canine STSs. Tissue banking, development of cell lines, and the ability to mobilize large-scale clinical trials will become essential in veterinary medicine to benefit both dogs and humans.

High-grade myxofibrosarcoma of the abdominal wall

The authors present a case of a 57-year-old man, who presented to the surgical clinic with a mass in the suprapubic region. A CT scan revealed a well-circumscribed lobular, heterogeneous soft tissue mass measuring 12×8.6×7.8 cm. The final histopathological diagnosis from the resection of the lesion was a myxofibrosarcoma (MFS), grade 3. The management of MFS includes surgical and oncological options which are reviewed here. These are aimed at complete excision and reducing the risk of local occurrence.

Extensive limb-sparing surgery with reconstruction for sarcoma of the hand and wrist

BACKGROUND

Sarcoma rarely involves the hand or wrist. Extensive surgical excision is the current standard of care. At the extremities, such as the hand and wrist, limb-sparing surgery with reconstruction to provide optimal function is increasingly performed. A descriptive case-series study of 16 patients with sarcoma of the hand and wrist managed using limb-sparing surgery is reported here.

MATERIAL AND METHODS

Of 19 patients with sarcoma of the hand or wrist treated between 1999 and 2012, 16 were managed using limb-sparing surgery. These were consecutive patients managed at a single-centre and studied retrospectively. The tumour involved the hand in 7 patients and the wrist in 9 patients. The procedure was primary in 6 patients, whereas 10 patients underwent secondary revision surgery. In 12 patients, reconstruction was performed for one or more of the following structures: nerves (n=2), tendons (n=3), bone (n=3), and/or skin (n=8). After surgical excision, the margins were R0 in 15 patients and R1 in 1 patient. At last follow-up, survival, pain, and function as reflected by the DASH and MSTS scores were assessed.

RESULTS

After the median follow-up of 4.5years [1-13], 15 patients were alive with no local recurrence and 1 patient had lung metastases. Mean values were 18 [0-49] for the DASH score and 88.8% [53-100] for the MSTS score.

DISCUSSION

Limb-sparing surgery reconciles the need to achieve complete tumour excision with the need to restore function. No limits should be placed on tumour excision, given the availability of effective reconstructive methods. The functional outcome depends on the tolerance of adjuvant treatments, most notably radiotherapy.

LEVEL OF EVIDENCE

IV, retrospective study.

The width of resection margins influences local recurrence in soft tissue sarcoma patients

BACKGROUND

Patients with soft tissue sarcoma (STS) being treated following the standardized guidelines can still not be guaranteed to remain free from local recurrence (LR). A complete tumour resection has been accepted as a major prognostic factor for LR. This retrospective study was designed to analyse the influence of two different classifications of resection margins (R-classification and UICC-classification) on LR in STS patients.

MATERIALS AND METHODS

Of 411 patients treated at our institution for STS, 265 were eligible for statistical analysis. Kaplan-Meier curves and Cox regression models were used to assess the impact of an R0 resection according to the R-classification (resection margin clear but allowing <1 mm) and according to the UICC-classification (minimal resection margin ≥1 mm) on LR.

RESULTS

Survival curves showed a lower LR rate for R0 resections in the UICC-classification, namely 1.3%, 12% and 12% as compared to 2.1%, 9.5% and 16.5% for the R-classification. In multivariate analysis calculated separately for each classification, R1 resection as defined by the R-classification (HR: 11.214; 95%CI: 2.394-52.517; p = 0.002) as well as by UICC-classification (HR: 15.634; 95%CI: 2.493-98.029; p = 0.003) remained significant.

CONCLUSION

In our study, margin status according to both classifications represents an independent prognostic factor for LR in patients with STS following curative surgery. Local control rates were superior after a minimal resection margin of 1 mm (R0 by UICC-classification) compared to R0 resections after the R-classification.

Improvement of the initial management of sarcomas after the dissemination of evidence-based guidelines depends on the primary sarcoma location: a population-based study

BACKGROUND

Improvement of the initial management of sarcomas after the dissemination of evidence-based guidelines depends on the primary sarcoma location: a population-based study. To improve the initial management of adult sarcomas, a regional expert team in Northern France performed two actions: dissemination of evidence-based guidelines (EBG) for the management of soft tissue/visceral sarcoma and yearly educational symposia. The aim of this study was to measure the impact of the dissemination of EBG on the key-indicators of adult sarcoma management.

METHODS

We conducted a before-after population-based study (before: 2005 with 63 cases, after: 2008-2009 with 86 cases) in the Lille area (Northern France urban/sub-urban area with 800,000 inhabitants). The following were the key-indicators of adult sarcoma management: pre-therapeutic biopsy, appropriate tumour and chest imaging, expert interdisciplinary discussion, expert interdisciplinary discussion before the first treatment and in operated cases, the rate of R0 resection.

RESULTS

There was no statistically significant difference in patient and tumour characteristics for the two time periods in terms of gender, prior cancer, primary location, histological subtype, grade, size, metastasis and lymph node involvement. There was no statistically significant improvement in primary tumour imaging (83 versus 87%), chest imaging (67 vs 71%), pre-therapeutic biopsy (57 vs 58%). There was an improvement in expert multidisciplinary discussion (37 vs 45%) or discussion before the first treatment (26 vs 44%) but no statistically significant. However, when soft tissue and bone sarcomas were analysed separately, we observed statistically significant improvements in expert multidisciplinary discussion (50 vs 74%, p = 0.02) and R0 resection rate (58 vs 91%, p = 0.002). In contrast, in cases of visceral sarcoma, there was no improvement in expert multidisciplinary discussion (10 vs 16%, p = 0.7) or in R0 resection (88 vs 81%, p = 0.7).

CONCLUSIONS

The dissemination of EBG was associated with a limited improvement in sarcoma management when measured in this before-after population-based study, and this improvement was dependent on the primary location of the tumour. Efforts to implement these guidelines by all surgical teams that could treat sarcoma, including visceral sarcoma, need to be made.