Toward the use of diffuse reflection spectroscopy for intra-operative tissue discrimination during sarcoma surgery

Significance

Accurately distinguishing tumor tissue from normal tissue is crucial to achieve complete resections during soft tissue sarcoma (STS) surgery while preserving critical structures. Incomplete tumor resections are associated with an increased risk of local recurrence and worse patient prognosis.

Aim

We evaluate the performance of diffuse reflectance spectroscopy (DRS) to distinguish tumor tissue from healthy tissue in STSs.

Approach

DRS spectra were acquired from different tissue types on multiple locations in 20 freshly excised sarcoma specimens. A k -nearest neighbors classification model was trained to predict the tissue types of the measured locations, using binary and multiclass approaches.

Results

Tumor tissue could be distinguished from healthy tissue with a classification accuracy of 0.90, sensitivity of 0.88, and specificity of 0.93 when well-differentiated liposarcomas were included. Excluding this subtype, the classification performance increased to an accuracy of 0.93, sensitivity of 0.94, and specificity of 0.93. The developed model showed a consistent performance over different histological subtypes and tumor locations.

Conclusions

Automatic tissue discrimination using DRS enables real-time intra-operative guidance, contributing to more accurate STS resections.

How Is the Spectrum of Sarcoma Surgery Assessed?

PURPOSE

To meet the challenges of the precision medicine era, quality assessment of shared sarcoma care becomes pivotal. The MDT approach is the most important parameter for a successful outcome. Of all MDT disciplines, surgery is the key step to rendering sarcoma patients disease free; therefore, defining its spectrum is critical. To the best of the authors' knowledge, a comprehensive interoperable digital platform to assess the scope of sarcoma surgery in its full complexity is lacking.

METHODS

An interoperable digital platform on sarcoma surgery has been created to assess the clinical exposure, tumor characteristics, and surgical settings and techniques applied for both resections and reconstructions of sarcomas.

RESULTS

The surgical exposure of an individual surgeon over time served as a pilot. Over the study period of 10 years, there were 723 sarcoma board/MDT meetings discussing 3130 patients. A total of 1094 patients underwent 1250 surgical interventions on mesenchymal tumors by one single sarcoma surgeon. These included 615 deep soft tissue tumors (197 benign, 102 intermediate, 281 malignant, 27 simulator, 7 metastasis, 1 blood); 116 superficial soft tissue tumors (45 benign, 12 intermediate, 40 malignant, 18 simulator, 1 blood); and 519 bone tumors (129 benign, 112 intermediate, 182 malignant, 18 simulator, 46 metastasis, 14 blood, and 18 sequelae of first treatment). Detailed types of resections and reconstructions were analyzed.

CONCLUSIONS

An interoperable digital data platform on sarcoma surgery with transparent real-time descriptive analytics is feasible and enables large-scale definition of the spectrum of sarcoma surgery to meet the challenges of sarcoma precision care in the future.

Emergency Retroperitoneal Sarcoma Surgery for Preoperative Rupture and Hemoperitoneum: A Case Report

Retroperitoneal sarcoma (RPS) is a rare and heterogeneous tumor. A percutaneous core needle biopsy (PCNB) is required for obtaining a histological diagnosis of the condition and for planning the therapy. Surgery is the standard of care for RPS; it is a standardized procedure, and it should be performed in a referral sarcoma center. Sarcoma surgery is rarely performed on an urgent or emergent basis. In this report, we describe a case of a retroperitoneal leiomyosarcoma that presented with spontaneous rupture and hemoperitoneum, which required surgical treatment in an urgent manner. To our knowledge, this is the first case of hemoperitoneum due to RPS rupture to be reported in the literature.

Intravenous Leiomyosarcoma of the Lower Extremity: As Peripheral as It Gets

Leiomyosarcomas of the vascular system (vLMSs) are rare tumors that commonly originate from large proximal and central veins. Pancreatic metastasis is rare for sarcomas, and surgical excision with large margins is the treatment of choice. We present a case of a 32-year-old female with primary vLMS originating from the distal crural veins and local invasion of the fibula. A prior open biopsy site was suboptimal. The patient was treated with neoadjuvant chemotherapy and radiotherapy, followed by surgery. The follow-up radiological imaging showed pancreatic head metastasis, which is also an extremely rare site for vLMS.

Combined pedicled superficial circumflex iliac artery perforator (SCIP) flap with lymphatic tissue preservation and lymphovenous anastomosis (LVA) for defect reconstruction and lymphedema-lymphocele prevention in thigh sarcoma surgery: Preliminary results

BACKGROUND

Sarcoma surgery often requires large tissue resection to be treated safely. When the tumor is localized in the groin and/or medial thigh, lymphocele and lymphedema are common complications because of the rich lymphatic network present there. The aim of this study is to share the outcome of seven patients who received defect reconstruction in this area with combined pedicled superficial circumflex artery perforator (SCIP) flap with lymphatic tissue preservation and lymphovenous anastomosis (LVA) for prevention of lymphatic complications.

PATIENTS AND METHODS

Seven patients who underwent surgical resection of sarcoma in the groin and/or adductors compartment received defect reconstruction with pedicled SCIP flap combined with LVA. For a better dead space obliteration, four of them also received an additional tissue flap: two pedicled deep inferior epigastric perforator flaps and two free anterolateral thigh flaps. Indocyanine green lymphography was performed in all cases to identify the lymphatic pathway, make the preoperative marking and check the patency of the anastomoses.

RESULTS

All seven patients were successfully treated reaching a good aesthetic result and a full range of motion. No immediate nor delayed complications such as lymphocele or lymphorrhea and early extremity lymphedema were observed during the follow up (range: 6-9 months; mean: 7.3) and no secondary procedures were required.

CONCLUSIONS

The combination of the pedicle SCIP lymphatic tissue transfer with LVA seems to be effective in preventing the development of lymphatic sequelae after large resections in the medial thigh.

Treatment at low-volume hospitals is associated with reduced short-term and long-term outcomes for patients with retroperitoneal sarcoma

BACKGROUND

Retroperitoneal sarcomas (RPS) are rare tumors for which complete surgical resection remains the mainstay of treatment. The objective of the current study was to determine the impact of hospital case volume on outcomes in patients with RPS.

METHODS

A total of 6950 patients with primary RPS who underwent surgical resection were identified from the National Cancer Data Base (1998-2011). Treating hospitals were classified by annual case volume; low-volume hospitals (LVHs) and high-volume hospitals (HVHs) were defined as those with ≤10 cases per year and >10 cases per year, respectively. Overall survival (OS) was compared using Kaplan-Meier curves. Cox proportional hazard models were created to compare risks.

RESULTS

Of the 1131 reporting hospitals, the majority (1127 hospitals; 99.6%) were LVHs treating the majority of patients (6270 patients; 90.2%). Patients treated at LVHs were more likely to have lower grade and smaller tumors, receive radiotherapy, and undergo incomplete macroscopic (R2) resection. Patients treated at HVHs had lower 30-day readmission rates (1.8% vs 3.4%; P<.001), 30-day (1.9% vs 3.1%; P=.004) and 90-day (3.2% vs 5.7%; P=.007) mortality, longer median OS (76.2 months vs 64.2 months; P<.001), and higher 5-year OS rates (58% vs 52%; P<.001). After controlling for age, sex, insurance status, tumor size, tumor grade, surgical resection margin status, and radiotherapy administration, treatment at an HVH was found to be independently associated with a reduced risk of death (hazard ratio, 0.77; 95% confidence interval, 0.65-0.91 [P=.003]).

CONCLUSIONS

Primary RPS are rare tumors, and to our knowledge few surgeons and institutions have significant experience and expertise in their multidisciplinary management and surgical resection. Although additional studies are needed, patient outcomes may be impacted by the case volume and expertise of the treating facility.

Outcomes of unplanned sarcoma excision: impact of residual disease

This study aimed to compare the oncological results between unplanned excision (UE) and planned excision (PE) of malignant soft tissue tumor and to examine the impact of residual tumor (ReT) after UE. Nonmetastatic soft tissue sarcomas surgically treated in 1996-2012 were included in this study. Disease-specific survival (DSS), metastasis-free survival (MFS), and local-recurrence-free survival (LRFS) were stratified according to the tumor location and American Joint Committee on Cancer Classification 7th edition stage. Independent prognostic parameters were identified by Cox proportional hazard models. Two-hundred and ninety PEs and 161 UEs were identified. Significant difference in oncological outcome was observed only for LRFS probability of retroperitoneal sarcomas (5-year LRFS: 33.0% [UE] vs. 71.0% [PE], P = 0.018). Among the 142 UEs of extremity and trunk, ReT in re-excision specimen were found in 75 cases (53%). UEs with ReT had significantly lower survival probabilities and a higher amputation rate than UEs without ReT (5-year DSS: 68.8% vs. 92%, P < 0.001; MFS: 56.1% vs. 90.9%, P < 0.001; LRFS: 75.8% vs. 98.4%, P = <0.001; amputation rate 18.5% vs. 1.8%, P = 0.003). The presence of ReT was an independent poor prognostic predictor for DSS, MFS, and LRFS with hazard ratios of 2.02 (95% confidence interval (CI), 1.25-3.26), 1.62 (95% CI, 1.05-2.51) and 1.94 (95% CI, 1.05-3.59), respectively. Soft tissue sarcomas should be treated in specialized centers and UE should be avoided because of its detrimental effect especially when ReT remains after UE.