MR imaging in the assessment of residual tumour following inadequate primary excision of soft tissue sarcomas

Optimizing Morbidity in Unplanned Soft Tissue Sarcoma Excisions: Should We Skip the Reconstructive Ladder?

INTRODUCTION

Soft tissue sarcomas (STSs) are rare and diverse primary malignant tumors that comprise approximately 1% of all malignancies. Misdiagnoses and unplanned excisions of STSs are common due to the tumor's rarity, leading to secondary tumor bed excisions (TBEs). Reconstructive outcomes for TBEs remain poorly understood, prompting this study to address the knowledge gap and inform preoperative discussions.

METHODS

This was a retrospective cohort study of patients who underwent STS excisions at a quaternary cancer center. Patients were categorized into mass excision (ME) and TBE groups. Reconstructive approaches were divided into simple (primary closure, complex repair, skin grafts, local flaps) and advanced (pedicled or free flaps). The groups were compared for postoperative outcomes, including complications, recurrence, and death.

RESULTS

When simple reconstructive techniques were used, TBEs exhibited higher rates of overall and major complications, whereas MEs had higher rates of overall and minor complications. Intergroup analysis revealed that with simple reconstruction, rates of overall and major complications were higher in TBEs than in MEs, and rates of minor complications were higher in MEs than in TBEs. Regression analyses revealed that simple reconstruction of TBEs had 90% and 180% higher odds of major complications and reoperation compared to simple reconstruction of MEs ( P < 0.05).

CONCLUSION

TBEs, despite their smaller size, exhibited a heightened susceptibility to overall and major complications, challenging the notion that simpler techniques suffice in these cases. Our findings encourage the consideration of advanced reconstructive techniques for TBEs that may seem amenable to simple reconstructive techniques.

Optimal timing of re-excision in synovial sarcoma patients: Immediate intervention versus waiting for local recurrence

BACKGROUND

To investigate the difference in efficacy of re-excision in synovial sarcoma patients with and without residual tumor following unplanned excision, and to compare the prognostic outcomes of immediate re-excision versus waiting for local recurrence.

METHOD

This study included synovial sarcoma patients who underwent re-excision at our center between 2009 and 2019, categorized into groups based on unplanned excision and local recurrence. Analyzed endpoints included overall survival (OS), local recurrence-free survival (LRFS), and distant relapse-free survival (DRFS). Prognostic factors associated with these three different survival outcomes were analyzed through the use of Kaplan-Meier curves and Cox regression approaches.

RESULT

In total, this study incorporated 109 synovial sarcoma patients, including 32 (29.4%) with no residual tumor tissue identified after re-excision, 31 (28.4%) with residual tumor tissue after re-excision, and 46 (42.2%) with local recurrence after initial excision. Patients were assessed over a median 52-month follow-up period. The respective 5-year OS, 5-year LRFS, and 5-year DRFS rates were 82.4%, 76.7%, and 74.2% for the nonresidual group, 80.6%, 80.4%, and 77.3% for the residual tumor tissue group, and 63.5%, 50.7%, and 46.3% for the local recurrence group. There was no significant difference in OS of nonresidual group and residual group patients after re-excision (p = 0.471). Concurrent or sequential treatment with chemotherapy and radiotherapy significantly reduced the risk of metastasis and mortality when compared with noncombined chemoradiotherapy, and was more effective in the local recurrence group (p < 0.05).

CONCLUSION

Prompt and adequate re-excision is crucial for patients with synovial sarcoma who undergo initial inadequate tumor excision, and their prognosis is significantly better compared with patients who delay re-excision until local recurrence.

Detecting residual soft tissue sarcoma after unplanned excision; model-free analysis of dynamic contrast-enhanced MRI at short-term follow-up

OBJECTIVES

To evaluate diagnostic utility of additional DCE-MRI for detecting residual soft tissue sarcomas (STS) after unplanned excision (UPE).

METHODS

We retrospectively evaluated 32 patients with UPE of STS, followed by conventional MRI with DCE-MRI and wide excision (WE), between November 2019 and January 2022. Residual tumors on conventional MRI were categorized into three groups: Lesion-type-0, no abnormal enhancement, Lesion-type-1, an indeterminate lesion, and Lesion-type-2, a definite enhancing nodule. On DCE-MRI, ROIs were manually placed on enhancing areas of suspected residual tumor. The mean and 95th percentile values of AUC of time-intensity curve were calculated at 60, 90, and 120 s of Enhancement-cycle-1 and -2. Optimal DCE parameters were identified by ROC analysis. Diagnostic performance of conventional MRI and DCE-MRI was compared using McNemar's test.

RESULTS

On WE, residual tumor was present in 23 (71.9%) of 32 patients. On MRI, Lesion-type-1 was found in 16/32 (50%) patients and Lesion-type-2 in 16/32 (50%). The optimal DCE parameter was the 95th percentile value of AUC at 120s of Enhancement-cycle-2. The sensitivity, specificity, and AUC were as follows: 65.2% (95% CI, 45.8-85.7%), 88.9% (CI, 68.4-100%), and 0.77 (CI, 0.62-0.92) for conventional MRI, and 100%, 55.6% (CI, 23.1-88.0%), and 0.78 (CI, 0.61-0.95) for combined conventional and DCE-MRI.

CONCLUSIONS

Additional DCE-MRI aided in detecting residual STS after UPE, particularly in cases without definite soft tissue nodular enhancement.

ADVANCES IN KNOWLEDGE

Close follow up may be suggested for patients showing abnormality in DCE-MRI, with more suspicion of residual tumor.

Oncological and functional outcomes of planned and unplanned excision of soft tissue sarcoma: A retrospective study

BACKGROUND

In soft tissue sarcomas, the oncological and functional outcomes between planned excision and unplanned excision with additional wide resection remains controversial. The purpose of this study is to determine the impact of unplanned excision on oncological and functional outcomes.

METHODS

A retrospective single-center study was performed. Patients with soft tissue sarcoma surgically treated in 2005-2019 were included in this study. A total of 120 patients consisting of planned excision (PE) group (n = 88), and unplanned excision (UE) group (n = 32) were included. Overall-survival (OS), local recurrence-free survival (LRFS), metastasis-free survival (MFS), disease-free survival (DFS), incidence rate of reconstructive surgery and musculoskeletal tumor society (MSTS) score were assessed. Propensity score matching method was used in statistical analysis.

RESULTS

The 5-year survival rate of OS, LRFS, MFS, and DFS did not differ between the PE and UE groups, however, rates of reconstructive surgery were higher in the UE group (PE: 48% vs. UE: 84%, p < 0.001). These results did not differ (PE: 41% vs. UE: 82%, p = 0.012) after propensity score matching was performed to align the backgrounds with difference in tumor size and depth. For MSTS score, the total score and "pain" and "emotional acceptance" scores were higher in the PE group before propensity score matching. The "pain" and "emotional acceptance" scores were higher in the PE group after propensity score matching also.

CONCLUSIONS

Unplanned excision did not deteriorate oncological outcomes, however unplanned excision lead to unnecessary reconstructive surgery. Unplanned excision adversely affected patient-reported outcomes without worsening pure functional outcomes.

A risk factor analysis for local recurrence of bone and soft tissue sarcoma treated with carbon ion radiotherapy: A retrospective cohort study at a single institution

AIM

Carbon ion radiotherapy is well-recognized as an excellent radiation modality that is suitable for treating unresectable bone and soft-tissue sarcoma of the trunk, spine, and pelvis; however, further study is needed to improve the local control rate. The current study examined the risk factors of the local recurrence of sarcomas after carbon ion radiotherapy.

METHODS

Patients with inoperable bone and soft-tissue sarcomas treated with carbon ion radiotherapy in our institute from 2010 to 2018 were retrospectively analyzed. Among them, 87 patients were eligible for this study. We divided the instances of local recurrence into two types, in-field and out-field recurrence, and evaluated the predictors for the risk of local recurrence such as the age at the treatment, sex, histopathological diagnosis, standard uptake value on fluorodeoxyglucose positron emission tomography, and the clinical target volume for each recurrence using a Cox proportional hazards model.

RESULTS

A multivariate analysis revealed that the tumors with a post-treatment standard uptake value of more than 3.84 on positron emission tomography had a significantly high risk of in-field recurrence (hazard ratio, 3.42; p = .03). Furthermore, postoperative lesions were a risk factor for out-field recurrence (hazard ratio, 3.82; p < .01).

CONCLUSION

The current study revealed that sarcomas maintaining a high glucose metabolic activity after carbon ion radiotherapy carried a risk of in-field recurrence, and the most significant risk factor of out-field recurrence was identified to be surgery before CIRT.

Diagnostic performance of MRI in detecting residual soft tissue sarcoma after unplanned excision: Systematic review and meta-analysis

OBJECTIVE

To investigate, in a systematic review and meta-analysis, the diagnostic performance of MRI in detecting residual disease after unplanned excision of soft tissue sarcoma.

METHODS

Medline and Embase were searched for original studies on the diagnostic performance of MRI detecting residual soft tissue sarcoma after unplanned excision. Study quality was assessed using QUADAS-2. Sensitivity and specificity were pooled using a bivariate random-effects model. A Chi-squared test was used to test for heterogeneity.

RESULTS

Ten studies were included, comprising a total of 469 patients. Median frequency of residual soft tissue sarcoma was 54.6% (range 31.6-73.1%). There was high risk of bias with respect to flow and timing in one study. There were applicability concerns with respect to patient selection in four studies. Nine studies reported to use the presence of a mass as a diagnostic criterion for residual soft tissue sarcoma. Sensitivities of included studies ranged between 36.4% and 86.7%, and specificities ranged between 77.8% and 100%. Pooled sensitivity was 65.9% (95% confidence interval [CI]: 55.5-74.9%) and pooled specificity was 85.1% (95% CI: 79.1-89.6%). The area under the summary receiver operating characteristic curve was 0.852. The included studies were statistically heterogeneous in their estimates of sensitivity (P = 0.016) and statistically homogeneous in their estimates of specificity (P = 0.793).

CONCLUSION

The presence of a mass is the most commonly reported diagnostic criterion to diagnose residual soft tissue sarcoma after unplanned resection. MRI achieves moderate sensitivity and fairly high specificity. Pooled estimate of sensitivity was subject to heterogeneity, which needs further exploration.

Clinical Outcome of Dermatofibrosarcoma Protuberance. Report From the Bone and Soft Tissue Tumor (BSTT) Registry in Japan

BACKGROUND

Owing to its rarity, dermatofibrosarcoma protuberance (DFSP) is often inappropriately excised. After unplanned excision (UE), additional excision is commonly performed. We aimed to elucidate the effect of additional excision after UE.

PATIENTS AND METHODS

We examined 306 patients with primary DFSP. We analyzed surgical outcomes in 291 patients who received planned excision (PE) or additional excision after UE.

RESULTS

Of 306 patients, 194 received PE and the remaining 112 received UE. Of 112 patients, 97 received additional excision after UE. Additional surgery due to complications was more frequent in patients with UE than in those with PE. The 5-year local recurrence-free rate in patients without additional excision after UE was significantly worse than that in those with additional excision after UE.

CONCLUSION

If UE is performed, we recommend additional excision for preventing local recurrence; however, the surgical wound should be carefully observed.

Re-excision after unplanned excision of soft tissue sarcoma: A systematic review and metanalysis. The rationale of systematic re-excision

In Soft Tissue Sarcomas (STS) referral centre many patients have already had an incomplete tumour resection. In the majority of specimen, tumoral residual is detected and linked to a worsen prognosis. Systematic surgical re-resection of the scar tissue area is often performed. Some authors suggested to postpone re-resections until a clinically evident local recurrence is detected. A searching strategy was applied to Pubmed-Central and Ovid Medline. Odds ratio (OR) for local recurrence (LR), distant metastasis (MTS) or overall survival (OS) were calculated comparing patients who had tumour residual to people who hadn't. OR of local recurrences, distant metastasis and OS were calculated in planned vs unplanned-excisions groups. OR to develop a metastasis and OS after a local recurrences were calculated. Residual tumour led to an OR for LR of 3,56, OR of MTS was 3,42; OR of decreased OS was 3,42. Having a LR lead to a OR of 1,55 for MTS and to a OR of decreased OS of 2,32. Patients who underwent a re-excision compared to planned surgery did not have an increased OR of LR and had an OR to develop a MTS of 0,56. Our data confirm that there is a strong correlation between local recurrences, distant relapses and overall survival. Although there is a selection bias; this analysis highlights the optimal oncological outcome in patients who underwent re-resection. The rationale for systematic re-resection after unplanned excision of soft tissue sarcomas is very strong and this treatment remains the gold standard of care in these patients.

Imaging of Soft Tissue Tumors

Differentiation of malignant from benign soft tissue tumors is challenging with imaging alone, including that by magnetic resonance imaging and computed tomography. However, the accuracy of this differentiation has increased owing to the development of novel imaging technology. Detailed patient history and physical examination remain essential for differentiation between benign and malignant soft tissue tumors. Moreover, measurement only of tumor size based on Response Evaluation Criteria In Solid Tumors criteria is insufficient for the evaluation of response to chemotherapy or radiotherapy. Change in metabolic activity measured by ¹⁸F-fluorodeoxyglucose positron emission tomography or dynamic contrast enhanced-derived quantitative endpoints can more accurately evaluate treatment response compared to change in tumor size. Magnetic resonance imaging can accurately evaluate essential factors in surgical planning such as vascular or bone invasion and "tail sign". Thus, imaging plays a critical role in the diagnosis and treatment of soft tissue tumors.

Standard Treatment Remains the Recommended Approach for Patients with Bone Sarcoma Who Underwent Unplanned Surgery: Report from the Japanese Musculoskeletal Oncology Group

Background

The outcomes of unplanned surgery for bone sarcomas have not been frequently discussed. However, it is important to recognize patterns, treatment, and clinical outcomes of unplanned surgeries for patients with bone sarcomas. This multicenter study aimed to characterize the clinical outcomes of patients with bone sarcomas who underwent unplanned surgeries.

Patients and Methods

Data of 43 patients with bone sarcomas who underwent unplanned surgery between 2006 and 2017 were obtained from 23 hospitals in Japan. These included 18 cases of osteosarcoma, 9 of Ewing sarcoma, 8 of chondrosarcoma, and 6 of undifferentiated pleomorphic sarcoma. The study included 28 men and 15 women, with a mean age of 46 years. The mean follow-up duration was 59 months.

Results

The main primary tumor sites were the femur (n = 19), spine (n = 6), pelvis (n = 5), tibia (n = 3), and humerus (n = 3). The primary diagnoses were benign bone tumor (n = 24), trauma (n = 7), bone metastasis (n = 5), osteomyelitis (n = 4), degeneration (n=2), and unknown (n = 1). As unplanned surgeries, curettage, with or without bone graft, was performed in 26 patients; internal fixation was performed in 7; spinal surgery in 5; arthroplasty in 4; and arthroscopy in one. Thirty-eight patients received additional standard treatments. Thirty-four of these patients underwent surgical tumor resections, including amputation (n = 10), and the remaining 4 received radiotherapy or carbon ion radiotherapy as additional standard treatments. The 5-year disease-specific survival (DSS) rates in patients with osteosarcoma, Ewing sarcoma, and chondrosarcoma were 65.5%, 58.3%, and 72.9%, respectively. Twelve (27.9%) patients developed local recurrences (LR); among the total 43 patients studied, the 5-year DSS rates were significantly worse for those who developed LR compared to those who did not (p = 0.03). The 5-year DSS rates in patients with and without LR were 44% and 73.8%, respectively.

Conclusion

We recommend that patients who have undergone unplanned surgery be administered standard treatment, including the option of amputation because herein, LR was shown to be a risk factor for decreased DSS.

Does Unplanned Soft Tissue Sarcoma Surgery Have a Negative Effect on Prognosis?

BACKGROUND

We aimed to compare the oncological outcomes of patients who underwent re-excision following unplanned surgery and those who underwent planned surgery.

METHODS

Patients who were referred to our hospital after a mass was inappropriately resected and reported to have a malignant pathology with a positive surgical margin, as well as patients diagnosed with malignant soft tissue tumors, and operated on following a multidisciplinary assessment and staging between 2012 and 2018. All patients were followed up at least 6 months.

RESULTS

Our study included a total of 125 patients. Forty percent (n = 50) underwent unplanned excision and sixty percent (n = 75) underwent planned excision.There was no statistically significant difference in the survival curves between the two groups (p = 0.248). Tumor size was larger, and the rate of deep-localized tumors was higher in patients undergoing planned surgery than in the unplanned surgery group (p = 0.001). The rate of tumors localized in the upper extremities was significantly higher in the unplanned surgery group than in the planned surgery (p = 0.033). MRI examinations could detect residual tumors with an accuracy of 80%. Age (>48 years), tumor size (>8 cm), tumor grade (grade 3), and distant organ metastasis at follow-up, which were among risk factors found to have a significant effect on mortality.

CONCLUSION

Patients undergoing re-excision after an inappropriate resection and undergoing planned resection had a similar prognosis. Superficial, upper extremity-localized, and relatively small-size tumors are more prone to inadequate surgical resection. MRI can be used to detect residual tumors at a high rate in patients who have undergone unplanned surgery. Distant organ metastasis is the most important factor affecting survival.

Effect of unplanned excision of soft tissue sarcomas on skin defects and reconstructive procedures

Unplanned excision (UE) is defined as a procedure wherein a surgeon operates a tumor resection without appropriate preoperative diagnostic modalities and without the intent to achieve tumor-free margins. Generally, the reconstruction rate after UE is higher than that after planned excision (PE). The present study aimed to investigate how the reconstructive procedure and size of skin defect could be influenced. We reviewed the cases of 442 patients who underwent the resection of soft tissue sarcoma. Patients were stratified into two groups (UE vs. PE). We compared the histologic grade, skin defect, reconstructive procedures, depth of the reconstruction layer. For superficial reconstructions, we also compared procedures involving skin graft-only or flap. 105 cases (23.8%) were UE. Histologic grade in PE was significantly higher (p = .024). The reconstruction rate and size of skin defect in UE was significantly higher (76.2% vs. 27.3%, p < .001) and larger (124.5 cm² vs. 65.7 cm², p < .001). The rate of deep layer reconstruction was significantly higher in PE (7.5% vs. 26.1%, p = .001). In superficial reconstructions, 18 (24.3%) skin graft-only procedures were performed in UE and 15 (22.1%) in PE, all other superficial reconstructive procedures involved flap, and there was no significant difference (p = .45). Skin defects were 1.9 times larger after UE than PE. UE did not affect the superficial reconstructive procedure.

Inadvertent excision of malignant soft tissue tumours

Inadvertent excision of lumps which turn out to be sarcomas is not uncommon.Imaging has a limited role in detecting microscopic residual disease but can show the extent of the previous surgical field.Standard treatment is wide re-excision, usually combined with radiotherapy.Residual tumour is found in an average of 50% of reported cases.The presence of residual disease is an adverse prognostic factor.All lumps bigger than a golf ball should have a diagnosis prior to excision. Cite this article: EFORT Open Rev 2019;4 DOI: 10.1302/2058-5241.4.180060.

Systematic review on the utility of magnetic resonance imaging for operative management and follow-up for primary sarcoma-lessons from extremity sarcomas

Primary sarcomas of the vertebral column affect roughly 5 in every million persons annually, of which half to one-third are malignant. Treatment of these lesions requires multimodal management, often employing attempts at en bloc resection of the lesion with negative margins. This may be facilitated using magnetic resonance imaging for preoperative margin planning, but current literature is lacking regarding the use of such imaging to accurately predict planned surgical margins. Here we review prior studies describing the use of magnetic resonance imaging for en bloc resection of sarcomas of the extremities to identify learning points for application to the treatment of spinal neoplasms. We conducted a systematic review of the PubMed and EMBASE literature. Included studies described the accuracy of MRI for preoperative evaluation of tumor margins, intraoperative guidance for en bloc resection, or post-operative evaluation of residual or recurrent disease. All included studies described patients treated for osseous or soft tissue sarcoma of the limbs. We found 1,705 unique references of which 27 met criteria for inclusion. Seven studies reported MR had an overall diagnostic accuracy of 93.6-96% for preoperative margin evaluation with non-contrast T1 most accurately reflecting true margins. In the nine articles reporting results of MR-guided resection, negative margins were achieved in 88.8-100% of cases with a closest margin of 2-4 mm. Eleven articles combined reported the accuracy of MR for residual disease or local recurrence, with a mean sensitivity and specificity of 71.7% and 79.3%, respectively for residual disease and 87.9% and 85.9%, respectively for local recurrence. The current literature for appendicular musculoskeletal sarcoma suggests that MR is highly accurate for defining tumor margins preoperatively, guiding osteotomy cuts intraoperatively, and documenting recurrence or residual disease. Further evidence is necessary to evaluate the degree to which it can accurately guide osteotomy planning for en bloc resection of vertebral primaries.

MRI findings associated with microscopic residual tumor following unplanned excision of soft tissue sarcomas in the extremities

INTRODUCTION

MRI is often used to determine the presence of residual disease following unplanned excisions (UPE) of soft tissue sarcomas (STS). We sought to identify MRI features associated with histologic evidence of residual disease after TBE.

MATERIALS AND METHODS

This was an IRB-approved retrospective review of 27 patients with R1-type UPE of STS over a 32-month period, with subsequent MRI and TBE. MRI studies were retrospectively evaluated to determine depth of tissue involvement, presence of nodular enhancement, and maximum length of soft tissue edema normalized to extremity size. MRI findings were correlated with histology from unplanned excision and TBE.

RESULTS

Among the 21 subjects, there were 13 males and 8 females, mean age 58. Eighteen of 21 STS were grade 2 or 3. Deep compartments were involved in 5/21 cases. Original margins were positive in 17/21 UPE, with inadequate margin assessment in the remaining 4 cases. Residual tumor was present at TBE in 11/21 cases; it was found in 4/6 cases with nodular enhancement and 7/15 cases without nodular enhancement (sensitivity = 0.36; specificity = 0.80; PPV = 0.67; NPV = 0.53). Increased extent of soft tissue edema increased the likelihood of residual tumor at TBE (OR = 35.0; 95% CI = 1.6 to 752.7; p = 0.023).

CONCLUSION

Nodular enhancement is neither sensitive nor specific in predicting residual microscopic tumor in TBE following UPE. Extensive soft tissue edema on MRI after UPE increases the likelihood of finding a residual microscopic tumor, justifying ample margins at TBE and consideration of adjuvant therapy.

Impact of residual disease after "unplanned excision" of primary localized adult soft tissue sarcoma of the extremities: evaluation of 452 cases at a single Institution

BACKGROUND

Soft tissue sarcomas are often inappropriately excised; it is, however, still a matter of debate whether the presence of residual disease in the re-excision specimen can affect patients' prognosis. The aim of this study is to investigate the impact of re-excision after unplanned surgery of primary soft tissue sarcomas (STS) of the extremities.

PATIENTS AND METHODS

We retrospectively evaluated 452 adults with grade 2-3, localized STS (349 primary and 103 unplanned excisions).

RESULTS

In the re-excision group, a full 43% of the patients had residual tumor. The re-excision group achieved a significantly better outcome in terms of sarcoma-specific survival (SS) (p = 0.002), local recurrence (LR) (p = 0.004) and distant metastasis (DM) (p = 0.028). Residual tumor was associated with a higher risk of DM (p = 0.005).

CONCLUSION

We confirm that unplanned surgery does not compromise patients' prognosis; scar re-excision guarantees at least the same SS, LR and DM rates compared to STS primarily treated in a referral center. Routine use of radiation therapy after re-excision could improve local control. Distant metastases seem to be negatively affected by the presence of residual tumor, and therefore, the use of CT in deep and large STS is suggested. The main goal is to avoid unplanned surgery by referring suspected lumps (especially deep, large, increasing in size) to a specialist center.

Predictors of residual disease after unplanned excision of soft tissue sarcomas

BACKGROUND

Unplanned excision of soft tissue sarcomas (STS) is an important quality of care issue given the morbidity related to tumor bed excision. Since not all patients harbor residual disease at the time of reexcision, we sought to determine predictors of residual STS following unplanned excision.

METHODS

We identified 76 patients from a prospective database (January 1, 2008-September 30, 2014) who received a diagnosis of primary STS following unplanned excision on the trunk or extremities. We used univariable and multivariable analyses to evaluate predictors of residual STS as the primary endpoint. We calculated the sensitivity, specificity, and accuracy of interval magnetic resonance imaging (MRI) to predict residual sarcoma at reexcision.

RESULTS

Mean age was 52 y, and 63.2% were male. 50% had fragmented unplanned excision. Among patients undergoing reexcision, residual STS was identified in 70%. On univariable analysis, MRI showing gross disease and fragmented excision were significant predictors of residual STS (odds ratio, 10.59; 95% CI, 2.14-52.49; P = 0.004 and odds ratio, 3.61; 95% CI, 1.09-11.94; P = 0.035, respectively). On multivariable analysis, tumor size predicted distant recurrence and overall survival. When we combined equivocal and positive MRI, the sensitivity and specificity of MRI for predicting residual STS were 86.7% (95% CI, 73.2%-95.0%) and 57.9% (95% CI, 33.5%-79.8%), with an overall accuracy of 78.1% (95% CI, 66.0%-87.5%).

CONCLUSIONS

About 70% of patients undergoing repeat excision after unplanned excision of STS harbor residual sarcoma. Although interval MRI and fragmented excision appear to be the most significant predictors of residual STS, the accuracy of MRI remains modest, especially given the incidence of equivocal MRI.

Unplanned excision of soft-tissue sarcomas: current concepts for management and prognosis

➤ Biopsy, staging, preoperative imaging and planning, as well as surgical treatment of soft-tissue sarcomas, are best carried out in specialized sarcoma centers, with the support of a multidisciplinary tumor board.➤ Tumor bed excision is recommended after most unplanned excisions, with a goal of obtaining complete tumor removal with an appropriately wide margin of resection.➤ The surgical resection area tends to be more extensive during tumor bed excision than during primary resection because of the need to resect potential areas of contamination, resulting in the need for more reconstructive procedures (flaps and skin grafts) and wider radiation fields.➤ Unplanned excisions are associated with an increased rate of local recurrence related to residual disease and positive margins after tumor bed excision, a deep location, and certain histologic subtypes, such as malignant peripheral nerve sheath tumor, myxofibrosarcoma, and dermatofibrosarcoma protuberans.➤ While adjuvant radiation therapy has not been found to mitigate the risk of local recurrence in unplanned excisions, it is generally utilized in the treatment of unplanned excisions as it is in the treatment of primary soft-tissue sarcomas.➤ Given the surgical and oncologic sequelae of unplanned excisions, prevention through the diffusion of concepts by means of provider education on how to approach soft-tissue masses, which can be potential soft-tissue sarcomas, is the best strategy.

Predictive value of magnetic resonance imaging in determining presence of residual disease after marginal excision of unsuspected soft tissue sarcomas of the hand

PURPOSE

Diagnosis of a soft tissue sarcoma of the hand is at times made only in retrospect after marginal excision of a presumed benign soft tissue mass. Magnetic resonance imaging (MRI) helps determine the presence of residual disease and the extent of contamination caused by marginal excision of unsuspected soft tissue sarcomas and assists in the planning of definitive treatment with surgery and radiotherapy when required. We sought to determine the accuracy of MRI in detecting residual sarcoma after marginal excision.

METHODS

We retrospectively studied case records and imaging studies for all patients with soft tissue sarcomas of the hand evaluated and treated at our institution from 1996 to 2005. We included in this study 33 patients who underwent definitive surgery at our center after prior marginal excision. MRI scans done before definitive wide resection were classified as positive or negative for residual tumor. A musculoskeletal radiologist, blinded to the sarcoma type, findings on histopathology, and surgery, reviewed 19 scans to see whether the accuracy could be improved.

RESULTS

There were 8 epithelioid sarcomas, 6 synovial sarcomas, 4 malignant fibrous histiocytomas, 2 leiomyosarcomas, 2 liposarcomas, 2 myxofibrosarcomas, and one each of 9 other diagnoses. A total of 11 were low-grade and 22 were high-grade tumors, with 4 superficial and 29 deep tumors. Pathology examination after definitive wide resection or partial hand amputation showed that 15 patients had residual tumor, 9 gross and 6 microscopic. The sensitivity of MRI in detecting residual soft tissue sarcoma of the hand was 60%, specificity was 78%, positive predictive value was 69%, and negative predictive value was 70%. The sensitivity of MRI in detecting gross residual soft tissue sarcoma of the hand was 89%, specificity was 79%, positive predictive value was 62%, and negative predictive value was 95%. Even when an experienced musculoskeletal radiologist reassessed 19 MRI scans, the accuracy did not improve.

CONCLUSIONS

Magnetic resonance imaging does not reliably detect residual gross or microscopic soft tissue sarcoma after marginal excision of unsuspected soft tissue sarcomas of the hand, with residual tumor not readily distinguished from postoperative change. The absence of disease on MRI should not be used as the sole criterion in determining whether a repeat resection should be performed.

TYPE OF STUDY/LEVEL OF EVIDENCE

Diagnostic III.

Biopsy of bone and soft tissue tumours: hints and hazards

Although the diagnostic algorithm of a suspected bone or soft tissue tumour, as well as the biopsy itself, are well defined, avoidable errors still happen. Major flaws might lead to unnecessary tissue contamination resulting in amputations or recurrences. In the current review we will focus in particular on biopsy guidelines and possible biopsy-related problems such as haematomas, sampling errors, and postoperative fractures. Finally, we will provide ten simple rules for a successful biopsy.

Post-operative imaging of soft tissue sarcomas

Soft tissue sarcomas are uncommon malignancies that have a high risk of local recurrence despite adequate initial surgery. The aim of follow-up imaging with any malignancy is to detect recurrence promptly so that treatment can be instigated at the earliest possible opportunity. In this review article, we discuss the imaging modalities that can be employed to detect local recurrence following surgery for an extremity soft tissue sarcoma. The role of radiographs, computed tomography, magnetic resonance imaging and positron emission tomography is reviewed followed by a discussion on the imaging modalities useful in the detection of metastatic disease. Finally, we present a robust pathway that is suggested for the follow-up of patients with an extremity soft tissue sarcoma.

Evaluation of primary re-excision after recent inadequate resection of soft tissue sarcomas in dogs: 41 cases (1999–2004)

OBJECTIVE

To determine the efficacy of primary re-excision alone for treatment of soft tissue sarcomas after recent incomplete resection, the frequency and clinical importance of detecting residual tumor in resected scars, and prognostic factors associated with the procedure.

DESIGN

Retrospective case series.

ANIMALS

41 dogs.

PROCEDURES

Medical records of dogs that had undergone recent incomplete excision of a soft tissue sarcoma at a referring veterinary practice and subsequent re-excision of the scar at the Colorado State University Veterinary Medical Center were reviewed. Owners and referring veterinarians were contacted for follow-up information. Slides from re-excised specimens were reviewed. Dogs that underwent radiation therapy after the re-excision procedure were excluded.

RESULTS

41 dogs met the inclusion criteria, and long-term follow-up information was available for 39 dogs. Median follow-up time was 816 days. Local recurrence of tumor developed in 6 of 39 (15%) dogs, and distant metastasis occurred in 4 of 39 (10%) dogs. Healthy tissue margins of 0.5 to 3.5 cm were achieved at re-excision. Residual tumor was identified in 9 of 41 (22%) resected scars. No tumor-, patient-, or treatment-related variables were associated with local recurrence except for the presence of liposarcoma or fibrosarcoma or whether fine-needle aspiration had been performed prior to surgery.

CONCLUSIONS AND CLINICAL RELEVANCE

After incomplete resection of soft tissue sarcomas, resection of local tissue should be performed, even if excisable tissue margins appear narrow. A long-term favorable prognosis is achievable without radiation therapy or amputation. The presence of residual tumor in resected scar tissue should not be used to predict local recurrence.

Leitlinien der Biopsie von Knochen- und Weichteiltumoren

The biopsy of a suspected bone or soft tissue tumour is the final part of a strictly defined diagnostic algorithm. Due to the multitude of possible errors which could result in major consequences, such as amputations after a major contamination with tumour cells or a misdiagnosis, particular responsibility falls on the shoulders of the treating specialists.

Prevalence, extension and characteristics of fluid-fluid levels in bone and soft tissue tumors

The purpose of this study was to determine the prevalence, extension and signal characteristics of fluid-fluid levels in a large series of 700 bone and 700 soft tissue tumors. Out of a multi-institutional database, MRI of 700 consecutive patients with a bone tumor and MRI of 700 consecutive patients with a soft tissue neoplasm were retrospectively reviewed for the presence of fluid-fluid levels. Extension (single, multiple and proportion of the lesion occupied by fluid-fluid levels) and signal characteristics on magnetic resonance imaging of fluid-fluid levels were determined. In all patients, pathologic correlation was available. Of 700 patients with a bone tumor, 19 (10 male and 9 female; mean age, 29 years) presented with a fluid-fluid level (prevalence 2.7%). Multiple fluid-fluid levels occupying at least one half of the total volume of the lesion were found in the majority of patients. Diagnoses included aneurysmal bone cyst (ten cases), fibrous dysplasia (two cases), osteoblastoma (one case), simple bone cyst (one case), telangiectatic osteosarcoma (one case), "brown tumor" (one case), chondroblastoma (one case) and giant cell tumor (two cases). Of 700 patients with a soft tissue tumor, 20 (9 males and 11 females; mean age, 34 years) presented with a fluid-fluid level (prevalence 2.9%). Multiple fluid-fluid levels occupying at least one half of the total volume of the lesion were found in the majority of patients. Diagnoses included cavernous hemangioma (12 cases), synovial sarcoma (3 cases), angiosarcoma (1 case), aneurysmal bone cyst of soft tissue (1 case), myxofibrosarcoma (1 case) and high-grade sarcoma "not otherwise specified" (2 cases). In our series, the largest reported in the literature to the best of our knowledge, the presence of fluid-fluid levels is a rare finding with a prevalence of 2.7 and 2.9% in bone and soft tissue tumors, respectively. Fluid-fluid levels remain a non-specific finding and can occur in a wide range of bone and soft tissue tumors, both benign and malignant. Therefore, they cannot be considered diagnostic of any particular type of tumor, and the diagnosis should be made on the basis of other radiological and clinical findings.

Imaging and diagnostic strategy of soft tissue tumors in children

The diagnosis of a soft tissue mass in children is a common clinical situation. Most of the lesions are benign and can be treated conservatively or by non-mutilating surgery. Nevertheless, the possibility of a malignant soft tissue tumor must be systematically considered. The most frequent benign soft tissue lesions in children are vascular lesions, fibrous and fibrohistiocytic tumors and pseudotumors, whereas rhabdomyosarcomas account for 50% of all soft tissue sarcomas. A child presenting an atypical soft tissue mass should be managed by a multidisciplinary centre, and primary resection must be proscribed until a definite diagnosis has been established. The role of imaging is essential either to confirm the benign nature of the mass or to give arguments to perform a diagnostic biopsy. Clinical examination, conventional radiography and ultrasound with Doppler represent the first-line examinations and are sometimes sufficient to assess a diagnosis. In all other situations, MRI is mandatory to establish the probable nature of the lesion and to assess local extension.

Prognostic effect of re-excision in adult soft tissue sarcoma of the extremity

BACKGROUND

We explored the outcome of patients with primary adult soft tissue sarcoma (STS) of the extremities undergoing re-excision after previous unplanned surgery.

METHODS

A total of 597 consecutive adult patients with primary extremity STS were treated with conservative surgery at our institution over a 20-year time span. A total of 318 patients were referred after unplanned excisions, and the remaining 279 underwent primary resection at our center. The two groups significantly differed in tumor size and depth. The assessed end points were sarcoma-specific mortality, local recurrence, and distant metastasis. Univariable and multivariable analyses, adjusted for other prognostic factors, were performed in the competing risks framework.

RESULTS

The adjusted 10-year cumulative incidences in re-excised and primarily operated patients were, respectively, 18.7% and 16.4% (P = .535) for local relapse, 17.6% and 20.2% (P = .541) for metastasis, and 20.4% and 22.4% (P = .645) for mortality. Among patients who underwent re-excision, evidence of microscopic residual disease on pathologic examination had a significant prognostic effect on multivariable analysis for distant metastases (P = .002). A trend for survival was detected as well.

CONCLUSIONS

At a referral center with a liberal policy of re-excisions in adult primary STS of the extremities, the outcome of patients who underwent re-excision was similar to that of patients who had primary resections. Evidence of microscopic residual disease at re-excision was a marker of clinical aggressiveness.

The MR imaging appearances and natural history of seromas following excision of soft tissue tumours

Fluid collections (seromas) may accumulate at the site of surgery following excision of musculoskeletal soft tissue tumours. The aim of this retrospective study was to review the magnetic resonance (MR) imaging features of postoperative seromas identifying changes over time on follow-up scans. A total of 170 MR scans from 80 patients were reviewed showing one or more seromas. All patients had undergone previous surgery for a musculoskeletal soft tissue tumour. The typical MR appearances of a seroma were shown to be a well-defined oval or rounded (54%) soft tissue mass, arising at the site of previous surgery, with a thin, dark pseudocapsule, surrounding soft tissue oedema (80%), homogeneous contents that are hypointense (relative to adjacent muscle) on T1-weighted images (74%) and hyperintense on T2-weighted and STIR images (79%). Approximately one-quarter of cases revealed atypical features including hyperintense contents on T1-weighted (26%) and/or heterogeneous contents on T2-weighted images (21%), reflecting the breakdown of blood products and organization of the fluid collection. A distinctive fine feathery pattern arising from the inner surface of the seroma or from septations was identified in 10% of cases. In those patients who underwent one or more follow-up scans, the volume of the seromas decreased in 66% cases, remained unchanged in 15% and increased in 19%. Seromas are not an uncommon finding (<10% of cases) following surgery for a soft tissue tumour. The majority of cases show the typical MR features of a fluid collection. The pitfalls in differentiating an atypical seroma from a recurrent soft tissue sarcoma are discussed.