Intraoperative Evaluation of Soft Tissue Sarcoma Surgical Margins with Indocyanine Green Fluorescence Imaging

Soft tissue sarcomas (STS) are rare malignant tumors often associated with poor outcomes and high local recurrence rates. Current tools for intraoperative and definitive margin assessment include intraoperative frozen section and permanent pathology, respectively. Indocyanine green dye (ICG) is a historically safe fluorophore dye that has demonstrated efficacy for intraoperative margin assessment in the surgical management of both breast and gastrointestinal cancers. The utility of ICG in the surgical management of sarcoma surgery has primarily been studied in pre-clinical mouse models and warrants further investigation as a potential adjunct to achieving negative margins. This study is a prospective, non-randomized clinical study conducted on patients with confirmed or suspected STS. Patients younger than 18 years, with a prior adverse reaction to iodine or fluorescein, or with renal disease were excluded from the study. Intravenous ICG was infused approximately three hours prior to surgery at a dosage of 2.0-2.5 mg/kg, and following tumor resection, the excised tumor and tumor bed were imaged for fluorescence intensity. When scanning the tumor bed, a threshold of 77% calibrated to the region of maximum intensity in the resected tumor was defined as a positive ICG margin, according to published protocols from the breast cancer literature. ICG results were then compared with the surgeon's clinical impression of margin status and permanent pathology results. Out of 26 subjects recruited for the original study, 18 soft tissue sarcomas (STS) were included for analysis. Three subjects were excluded for having bone sarcomas, and five subjects were excluded due to final pathology, which was ultimately inconsistent with sarcoma. The average age of patients was 64.1 years old (range: 28-83), with an average ICG dose of 201.8 mg. In 56% (10/18) of patients, ICG margins were consistent with the permanent pathology margins, with 89% specificity. The use of ICG as an intraoperative adjunct to obtaining negative margins in soft tissue sarcoma surgery is promising. However, studies with larger sample sizes are warranted to further delineate the accuracy, optimal dosage, timing, and types of sarcoma in which this diagnostic tool may be most useful.

Sarcomas of the hand: A retrospective series of 26 cases

BACKGROUND

Hand sarcomas frequently suffer from a delayed diagnosis, and the current guidelines for their management are often not followed.

METHODS

The objectives of our study were to determine: (1) the rate of inadequate initial treatments; (2) the rates of mortality, recurrence, and complementary excision in a cohort of patients with a sarcoma of the hand who were treated at our reference center between 2000 and 2015.

RESULTS

The series comprised 26 patients (mean age 40 years). Of the 20 patients not initially treated at a reference center, 17 had inadequate initial treatment. Of the six patients treated at our center, one had inadequate initial care. Significantly more patients had inadequate initial care outside a reference center (p=0.0045). The cumulative probabilities of recurrence or metastases at 5 years were 15% and 30%, respectively. Survival by cumulative incidence was 71% at 5 years and 56% at 10 years.

CONCLUSIONS

Sarcomas of the hand are a deadly pathology. All diagnostic uncertainty warrants referral of the patient to a reference center.

LEVEL OF PROOF

IV.

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.

Analysis of Margin Classification Systems for Assessing the Risk of Local Recurrence After Soft Tissue Sarcoma Resection

Purpose To compare the ability of margin classification systems to determine local recurrence (LR) risk after soft tissue sarcoma (STS) resection. Methods Two thousand two hundred seventeen patients with nonmetastatic extremity and truncal STS treated with surgical resection and multidisciplinary consideration of perioperative radiotherapy were retrospectively reviewed. Margins were coded by residual tumor (R) classification (in which microscopic tumor at inked margin defines R1), the R+1mm classification (in which microscopic tumor within 1 mm of ink defines R1), and the Toronto Margin Context Classification (TMCC; in which positive margins are separated into planned close but positive at critical structures, positive after whoops re-excision, and inadvertent positive margins). Multivariate competing risk regression models were created. Results By R classification, LR rates at 10-year follow-up were 8%, 21%, and 44% in R0, R1, and R2, respectively. R+1mm classification resulted in increased R1 margins (726 v 278, P < .001), but led to decreased LR for R1 margins without changing R0 LR; for R0, the 10-year LR rate was 8% (range, 7% to 10%); for R1, the 10-year LR rate was 12% (10% to 15%) . The TMCC also showed various LR rates among its tiers ( P < .001). LR rates for positive margins on critical structures were not different from R0 at 10 years (11% v 8%, P = .18), whereas inadvertent positive margins had high LR (5-year, 28% [95% CI, 19% to 37%]; 10-year, 35% [95% CI, 25% to 46%]; P < .001). Conclusion The R classification identified three distinct risk levels for LR in STS. An R+1mm classification reduced LR differences between R1 and R0, suggesting that a negative but < 1-mm margin may be adequate with multidisciplinary treatment. The TMCC provides additional stratification of positive margins that may aid in surgical planning and patient education.

Surgical considerations when reporting MRI studies of soft tissue sarcoma of the limbs

Soft tissue sarcomas (STS) are rare tumours that require prompt diagnosis and treatment at a specialist centre. Magnetic resonance imaging (MRI) has become the modality of choice for identification, characterisation, biopsy planning and staging of soft tissue masses. MRI enables both the operating surgeon and patient to be optimally prepared prior to surgery for the likelihood of margin-negative resection and to anticipate possible sacrifice of adjacent structures and consequent loss of function. The aim of this review is to aid the radiologist in performing and reporting MRI studies of soft tissue sarcomas, with particular reference to the requirements of the surgical oncologist.

Upper extremity sarcoma: impact of current practice guidelines and controversies on reconstructive approaches

The goals of sarcoma management include both a cure and the functional preservation of involved tissues and adjacent critical structures with common opinions favoring immediate reconstruction. The question arises whether these goals are contradictory. This paper discusses the question based on the experience of 28 patients with different types of extremity sarcoma, with 24 surgically treated by the University of California San Diego (UCSD) orthopedic and plastic surgery team (2011–2016) and the collection of evidence from published practice guidelines, reviews, case studies, and clinical trials. Included are the impact of limb-sparing and functional reconstructive concepts, efforts regarding the adequacy of surgical margins, and the rationale of immediate versus delayed reconstructive approaches, and the disease-free status of sarcoma management.

Extremity Soft Tissue Sarcoma: Tailoring Resection to Histologic Subtype

Soft tissue sarcomas comprise tumors originating from mesenchymal or connective tissue. Histologic grade is integral to prognosis. Because sarcoma management is multimodal, histologic subtype should inform optimum treatment. Appropriate biopsy and communication between surgeon and pathologist can help ensure a correct diagnosis. Treatment often involves surgical excision with wide margins and adjuvant radiotherapy. There is no consensus on what constitutes an adequate margin for histologic subtypes. An appreciation of how histology corresponds with tumor biology and surgical anatomic constraints is needed for management of this disease. Even with the surgical goal of wide resection being obtained, many patients do not outlive their disease.

The Width of the Surgical Margin Does Not Influence Outcomes in Extremity and Truncal Soft Tissue Sarcoma Treated With Radiotherapy

BACKGROUND AND OBJECTIVES

It is unclear whether the quantitative width of the surgical margin influences outcomes in patients with extremity and truncal soft tissue sarcoma (STS) treated with radiotherapy (RT).

METHODS

We performed a retrospective review of 382 patients with localized extremity or truncal STS who underwent limb-sparing surgery and RT from 1983 to 2010, and we analyzed the significance of resection margin status and quantitative margin width on outcomes.

RESULTS

Surgical margins were positive in 68 (18%) patients and negative in 314 (82%) patients. For those patients with a reported quantitative margin width (n = 235), the width of the negative margin was ≤1 mm (n = 128), >1 mm and ≤5 mm (n = 79), and >5 mm (n = 28). At a median follow-up of 82 months, the local recurrence rates were 5.4% and 11.8% for margin-negative and margin-positive patients, respectively. There were no differences in the rates of local or distant recurrence nor of any survival outcome based on the quantitative width of the surgical margin, provided that it was negative.

CONCLUSIONS

In patients undergoing RT and limb-sparing surgery for STS, achieving a negative margin is essential for optimizing both local control and survival. However, the absolute quantitative width of the negative margin does not significantly influence outcome, and so attempts at wide margins of resection appear to be unnecessary. Importantly, the conclusions drawn from this study must not be applied to those patients undergoing surgery alone as the local treatment of their STS, in which case wider margins of resection may be necessary.

IMPLICATIONS FOR PRACTICE

In patients undergoing radiation therapy and limb-sparing surgery for soft tissue sarcoma, the quantitative width of the negative margin does not influence outcome, and so attempts at wide margins of resection appear to be unnecessary, especially when such attempts compromise the functional outcome. Importantly, the conclusions drawn from this study must not be applied to those patients undergoing surgery alone as the local treatment of their soft tissue sarcoma, in which case wider margins of resection may be necessary.

Management of Pelvic Chondroblastic Osteosarcoma after Urgent Spinal Decompression - A Report of 2 Cases

Introduction:

Pelvic sarcoma presenting with neurologic symptoms is rare. Workup of neurological deficits, whether elective or emergent should address the possibility of a space occupying lesion including pelvic sarcoma. Poor biopsy technique and incomplete workup of musculoskeletal tumors results in misdiagnosis or major errors in 18% of biopsies. The sequelae of a suboptimal biopsy include local recurrence, a more extensive resection, or extremity amputation. Pelvic chondroblastic osteosarcoma presenting with neurological deficits has not been previously reported. We report two cases of chondroblastic osteosarcoma that were treated with urgent decompression of the lumbar spine due to neurologic symptoms.

Case presentations:

Our two cases, a 25 year old Hispanic female and 22 year old Hispanic male, both presented with neurologic changes due to a space occupying tumor in the lumbar spine and pelvis. Both underwent spinal decompression following incomplete workup. A repeat biopsy was required in both cases due to a questionable initial diagnosis. Once the diagnosis was confirmed, they underwent definitive resection and treatment that was more morbid due to the primary decompressions.

Conclusion:

We stress the importance of proper biopsy techniques as well as the need to complete a full preoperative staging workup prior to any surgical procedures involving musculoskeletal tumors. We review the current literature on lumbar chondroblastic osteosarcomas and review the issues surrounding biopsy of musculoskeletal tumors. Our cases underline the need for complete workup and correct biopsy techniques to ensure patients have the best chance at tumor free survival with minimal morbidity.

Positron emission tomography (18)F-fluorodeoxyglucose uptake and prognosis in patients with bone and soft tissue sarcoma: A meta-analysis

PURPOSE

To investigate the prognostic significance of (18)F-FDG PET imaging in patients with bone and soft tissue sarcoma, a meta-analysis was conducted.

METHODS

Comprehensive literature searches were performed in PubMed, Embase, Web of Science and Cochrane Library. Pooled hazard ratio (HR) values were calculated to assess the correlations of pre-chemotherapy SUV (SUV1), post-chemotherapy SUV (SUV2), SUV Ratio, total lesion glycolysis (TLG) and metabolic tumor volume (MTV) with event-free survival (EFS) and overall survival (OS).

RESULTS

Twenty-three studies with 1261 patients were identified. The combined HRs for EFS were 1.84 (95% CI: 1.54-2.20) for SUV1, 2.92 (95% CI: 2.15-3.97) for SUV2, 1.90 (95% CI: 1.43-2.52) for SUV Ratio, 3.01 (95% CI: 1.36-6.67) for TLG and 2.32 (95% CI: 1.44-3.75) for MTV. The pooled HRs for OS were 1.85 (95% CI: 1.49-2.30) for SUV1, 2.00 (95% CI: 1.39-2.88) for SUV2, 2.20 (95% CI: 1.18-4.10) for SUV Ratio, 6.19 (95% CI: 2.17-17.66) for TLG and 2.67 (95% CI: 1.52-4.68) for MTV. Besides, high SUV1 was found to be significantly associated with higher rate of metastasis (RR 5.55, 95% CI: 2.75-11.18) and local recurrence (RR 1.87 95% CI: 1.28-2.72).

CONCLUSION

(18)F-FDG PET parameters of SUV1, SUV2, SUV Ratio, TLG and MTV may have effective prognostic significance for patients with bone and soft tissue sarcoma. (18)F-FDG PET imaging may be a promising tool to help predict survival outcomes of these patients.

Dosimetric comparison of 3-dimensional conformal radiation therapy and intensity modulated radiation therapy and impact of setup errors in lower limb sarcoma radiation therapy

PURPOSE

This study compared dosimetric data between 3-dimensional conformal radiation therapy (3DCRT) and intensity modulated radiation therapy (IMRT) plans in a population of patients with lower limb sarcoma immobilized with an in-house device and quantified the impact of systematic and random errors on these techniques. The dosimetric effects of displacements on target coverage and organs at risk (OARs) were considered.

METHODS AND MATERIALS

Plans were created for 11 postoperative patients using both 3DCRT and IMRT. The techniques were compared dosimetrically. Population-based systematic and random errors were applied and the results compared with the initial plans.

RESULTS

Higher target D95, D2, D98, and D50 and the best homogeneity index resulted with IMRT compared with 3DCRT. Systematic errors increased target D2 in IMRT. Random errors decreased target homogeneity in IMRT. Maximum bone dose was higher in IMRT than in 3DCRT. Neither error type increased OAR dose for either technique.

CONCLUSIONS

IMRT could become the favored lower limb sarcoma radiation therapy technique because of superior target coverage and homogeneity. Offline imaging can adequately correct for systematic errors in these patients when an in-house immobilization device is used.

The role of margins in extremity soft tissue sarcoma

For extremity soft tissue sarcomas, limb salvage is now standard of care. The extent of surgical margins is balanced with functionality of the resected limb. Although negative margins are the goal, the necessary width is unclear. Additional considerations for margin adequacy include presence of anatomic barriers such as fascia and periosteum, proximity of critical structures, receipt of adjuvant and neoadjuvant therapies, and histologic subtype. Multidisciplinary team discussion is critical for treatment planning.

Territorial inequalities in management and conformity to clinical guidelines for sarcoma patients: an exhaustive population-based cohort analysis in the Rhône-Alpes region

BACKGROUND

Sarcomas are rare cancers with great variability in clinical and histopathological presentation. The main objective of clinical practice guidelines (CPGs) is to standardize diagnosis and treatment.

METHODS

From March 2005 to February 2007, all patients diagnosed with localized sarcoma in the Rhône-Alpes region were included in a cohort-based study, to evaluate the compliance of sarcoma management with French guidelines in routine practice and to identify predictive factors for compliance with CGPs.

RESULTS

634 (71 %) patients with localized sarcoma satisfying the inclusion criteria were included out of 891 newly diagnosed sarcomas. Taking into account initial diagnosis until follow-up, overall conformity to CPGs was only 40 % [95 % confidence interval (CI) = 36-44], ranging from 54 % for gastrointestinal stromal tumor to 36 % for soft tissue sarcoma and 42 % for bone sarcoma. In multivariate analysis, primary tumor type [relative risk (RR) = 4.42, 95 % CI = 2.79-6.99, p < 0.001], dedicated multidisciplinary staff before surgery (RR = 4.19, 95 % CI = 2.39-7.35, p < 0.001) and management in specialized hospitals (RR = 3.71, 95 % CI = 2.43-5.66, p < 0.001) were identified as unique independent risk factors for conformity to CPGs for overall treatment sequence.

CONCLUSIONS

With only 40 % of total conformity to CPGs, the conclusions support the improvement of initial sarcoma management and its performance in specialized centres or within specialized dedicated networks.