Prognostic factors in superficial adult soft tissue sarcomas: analysis of a series of 105 patients

Small Subcutaneous Soft Tissue Tumors (<5 cm) Can Be Sarcomas and Contrast-Enhanced Ultrasound (CEUS) Is Useful to Identify Potentially Malignant Masses

Subcutaneous masses smaller than 5 cm can be malignant, in contrast with the international guidelines. Ultrasound (US) and magnetic resonance imaging (MRI) are useful to distinguish a potentially malignant mass from the numerous benign soft tissue (ST) lesions. Contrast-enhanced ultrasound (CEUS) was applied in ST tumors, without distinguishing the subcutaneous from the deep lesions. We evaluated CEUS and MRI accuracy in comparison to histology in differentiating malignant from nonmalignant superficial ST masses, 50% smaller than 5 cm. Sensitivity, specificity, and positive and negative predictive values (PPV, NPV) with their 95% confidence intervals (CI) were calculated. Of malignant cases, 44.4% measured ≤5 cm. At univariate analysis, no statistically significant differences emerged between benign and malignant tumors in relation with clinical characteristics, except for relationship with the deep fascia (p = 0.048). MRI accuracy: sensitivity 52.8% (CI 37.0, 68.0), specificity 74.1% (CI 55.3, 86.8), PPV 73.1% (CI 53.9, 86.3), and NPV 54.1% (CI 38.4, 69.0). CEUS accuracy: sensitivity 75% (CI 58.9, 86.3), specificity 37% (CI 21.5, 55.8), PPV 61.4% (CI 46.6, 74.3), and NPV 52.6% (CI 31.7, 72.7). CEUS showed a sensitivity higher than MRI, whereas PPV and NPV were comparable. Also, masses measuring less than 5 cm can be malignant and referral criteria for centralization could be revised.

The role of radiotherapy in the treatment of superficial soft-tissue sarcomas

AIMS

The existing clinical guidelines do not describe a clear indication for adjuvant radiotherapy (RT) in the treatment of superficial soft tissue sarcomas (STSs). We aimed to determine the efficacy of adjuvant RT for superficial STSs.

METHODS

We retrospectively studied 304 patients with superficial STS of the limbs and trunk who underwent surgical resection at a tertiary sarcoma centre. The efficacy of RT was investigated according to the tumour size and grade: group 1, ≤ 5 cm, low grade; group 2, ≤ 5cm, high grade; group 3, > 5 cm, low grade; group 4, > 5 cm, high grade.

RESULTS

The five- and ten-year local recurrence-free survival (LRFS) for all patients was 88% and 81%, respectively. While the efficacy of adjuvant RT was not proven in local control of all patients (five-year LRFS; RT+, 90% versus RT-, 83%; p = 0.074), the LRFS was significantly improved by adjuvant RT in group 2 (five-year LRFS; RT+, 96% versus RT-, 82%; p = 0.019), and group 4 (five-year LRFS; RT+, 87% versus RT-, 73%; p = 0.027). In groups 2 and 4, adjuvant RT significantly reduced the LR risk if the resection margin was clear but less than 5 mm; the LR rate was 7% with adjuvant RT compared with 26% with surgery alone (p = 0.003). There was no statistical relationship with the use of adjuvant RT and survival in every group.

CONCLUSION

Adjuvant RT reduces the risk of local recurrence in patients with superficial high-grade STS regardless of tumour size, especially when resection margin is less than 5 mm. Cite this article: Bone Joint J 2020;102-B(8):1088-1094.

Diagnosis and Management of Subcutaneous Soft Tissue Sarcoma

OPINION STATEMENT

The proper diagnosis and treatment planning for subcutaneous soft tissue sarcoma is very important. Soft tissue tumors can occur anywhere in the body, but if they occur subcutaneously, patients can easily notice a subcutaneous soft tissue mass. Therefore, it is possible to determine through recording, the growth speed of the mass, which is often difficult to obtain with deep-situated soft tissue masses. Palpation can also provide information about the firmness and mobility of the mass. Thus, history taking and physical examinations are informative for subcutaneous soft tissue tumors, compared to tumors that occur deeply. Because subcutaneous soft tissue tumors are easily recognized, they are often resected, without sufficient imaging analyses or thorough treatment planning. An operation performed based on such an inadequate preoperative plan is called a "whoops surgery." In the case of "whoops surgeries," subsequent radical surgery is required to remove additional areas, including hematomas that result from the initial surgery, that require a wider range of resection and soft tissue reconstruction. Therefore, as with deep-seated soft tissue tumors, it is important to conduct careful imaging examinations and make appropriate preoperative plans for subcutaneous soft tissue tumors. Subcutaneous soft tissue sarcomas often show an invasive pattern, and such tumors require a more careful assessment to prevent local recurrence after surgery. During surgery, it is necessary to remove the entire infiltration area along the fascia. Sometimes, an adequately wide excision is necessary, which is considered the minimum necessary procedure to eradicate the lesion. As noted above, clinicians who see patients with subcutaneous soft tissue tumors are encouraged to have sufficient knowledge and experience regarding the diagnosis and treatment. This article is intended for all doctors who deal with subcutaneous soft tissue tumors and focuses on essential points regarding their diagnosis and management.

Prognostic significance of microscopic tumor extension in local recurrence of myxofibrosarcoma and undifferentiated pleomorphic sarcoma

Myxofibrosarcoma (MFS) and undifferentiated pleomorphic sarcoma (UPS) frequently display infiltrative growth into the adjacent normal soft tissue. In this study, we aimed to determine whether the microscopic extension into surrounding normal tissue can influence the local recurrence of MFS and UPS. A total of 42 cases (22 MFS and 20 UPS) were examined. The length of the microscopic extension was measured from the edge of the main tumor mass to the end of infiltration. The length of 5.5 mm was selected as the optimal cut-off value that could predict local recurrence using the receiver operating characteristic (ROC) curve and Youden index. Longer length of microscopic extension was significantly correlated with the status of resection margin (P = 0.032). The group with longer length of microscopic extension (>5.5 mm) had significantly worse recurrence-free survival than the group with shorter length of microscopic extension (≤5.5 mm) (P = 0.000). Multivariate analysis revealed that the length of microscopic extension was independent predictors of recurrence-free survival (P = 0.018). In conclusion, microscopic extensions at the edge of the main mass into the surrounding normal tissue were observed in most MFS and UPS patients, and the length of microscopic extension was associated with local recurrence.

Patterns of care of superficial soft tissue sarcomas: it is not always just a lump

AIM

Superficial soft tissue sarcomas (S-STS) are generally considered low-risk tumors and have an excellent prognosis when treated with appropriate surgery and adjuvant therapy. However, they are often misdiagnosed then mistreated, leading to significant morbidity. This study aims to examine the patterns of care and outcomes of patients with S-STS, comparing those initially managed through sarcoma units versus elsewhere.

METHODS

Patients with S-STS from Prince of Wales Hospital in NSW (1995-2013) and Peter MacCallum Cancer Centre in Victoria (2009-2013) were identified from a national sarcoma database. Baseline variables, treatment and disease outcomes were recorded. Statistical tests performed included univariate and multivariate analyses, chi-square tests, as well as the Kaplan-Meier method for 5-year local recurrence and survival rates.

RESULTS

Eighty-nine patients were identified, with 35% initially managed at a sarcoma unit and 65% elsewhere. Patients initially managed at sarcoma units had larger tumors (>5 cm 39% vs 17%; P  =  0.036) with a trend to higher grade (61% vs 48%; P = 0.39). Patients that were initially managed outside a sarcoma unit more often underwent open surgical biopsies (P < 0.0005), had multiple operations (P < 0.0005) and had higher rates of local recurrences (24% vs 6.5%, P  =  0.038). They also had lower 5-year local recurrence-free survival rates (P = 0.022), but had higher metastasis-free survival (P = 0.014). On multivariate analysis, only larger STS size and male gender predicted for poorer metastasis-free survival (P = 0.042 and 0.018, respectively).

CONCLUSION

Patients with S-STS initially managed outside specialized sarcoma units undergo more operations, with risk of greater morbidity, and have greater risk of local recurrence.

Superficial Soft-Tissue Sarcomas Rarely Require Advanced Soft-Tissue Reconstruction following Resection

Objective:

Soft-tissue sarcomas are most frequently located deep within myofascial compartments. Superficial soft-tissue sarcomas (S-STS) are relatively less common and may be managed differently than deep sarcomas because generous resection margins are often possible without sacrificing critical structures. We sought to investigate the frequency and types of soft-tissue reconstructive procedures that are required following excision of S-STS.

Methods:

We reviewed 457 consecutively treated patients with S-STS with a minimum 2-year follow-up from our prospectively maintained database between 1989 and 2009.

Results:

Mean follow-up was 10.5 years (range, 2–23). Four hundred twenty-one tumors (91%) were excised with negative margins, 38 (8.3%) had microscopically positive margins, and three (0.7%) had grossly positive margins. One patient required an amputation. In 271 (58%) patients, the wounds were closed primarily. In comparison, 93 patients (20%) required a rotation flap, 70 (15%) required a split-thickness skin graft, and 23 (5%) underwent a free tissue transfer (ie, advanced reconstructive procedure). The overall complication rate was 12%, although 43% of patients undergoing free tissue transfer developed complications (P = 0.04). An unplanned excision before referral to our center was a risk factor for local recurrence (P = 0.03) when residual tumor was recovered in the reexcision specimen pathologically.

Conclusions:

Although concern about the morbidity associated with a free tissue transfer (ie, advanced reconstructive procedure) may potentially limit the adequacy of resection in some patients with S-STS, the results of this study showed that the majority of patients had complete excisions with negative margins and primary closure. Obtaining a negative margin when excising a known or suspected S-STS rarely requires an advanced reconstructive procedure and almost never results in loss of limb.

Soft Tissue Sarcoma of the Trunk and Extremities

The diagnostic methods and treatment modalities of soft tissue sarcomas have evolved with the multidisciplinary approach. The soft tissue sarcoma team must have specialists capable of using and combining modern methods of radiology and pathology, cytogenetics, tumour surgery, tissue transfer techniques, radiotherapy and chemotherapy for optimal local and systemic treatment. Limb sparing surgery combined with radiotherapy has lowered the amputation rate and maintained low rates of local recurrence. Reconstructive surgery facilitates treatment of patients with soft tissue sarcoma by permitting tumour resection with adequate margins, protects vital structures, enables early postoperative radiation therapy, maintains extremity length, and if necessary assists in palliative procedures. The ability to maintain function and aesthetics after tumour resection, and effective palliation improves the quality of life for these patients. Early recognition and appropriate referral to a tumour centre improve the outcome.

Outcomes of surgical treatment alone in patients with superficial soft tissue sarcoma regardless of size or grade

BACKGROUND AND OBJECTIVES

Currently, standard treatment of soft tissue sarcoma (STS) is wide local excision and adjuvant radiation, but radiation may be unnecessary in superficial STS. The primary objective is to assess local recurrence rates in patients treated with surgical management alone for superficial STS.

METHODS

A retrospective cancer registry review of patients treated with surgery alone for superficial STS at the Tom Baker Cancer Center (TBCC) was performed. Patient and tumor characteristics as well as recurrence data were collected.

RESULTS

Sixty-one patients met study criteria. Local and overall recurrence rates were 7/61 (11.5%) and 12/61 (19.7%), respectively. The proportion with a T2 tumor was 38.8% versus 33.3% (P = 0.69), with Grade 2 or 3 tumors was 59.2% versus 83.3% (P = 0.14), and with resection margins <1 cm was 28.6% versus 75.0% (P = 0.008) for patients without and with recurrence, respectively. Median time to recurrence was 1.7 (0.4-5.2) years.

CONCLUSIONS

Surgical resection alone appears to be a viable option for superficial STS that can save patients from potential side effects of radiation. The association between recurrence and inadequate margins (<1 cm) requires additional treatment be offered to this subset of patients.

Homogenous Good Outcome in a Heterogeneous Group of Tumors: An Institutional Series of Outcomes of Superficial Soft Tissue Sarcomas

Introduction. Superficial soft tissue sarcomas (S-STS) are generally amenable to wide excision. We hypothesized that local recurrence (LR) should be low, even without radiation therapy (RT), and sought to examine the contribution of depth to LR and OS. Methods. Patients with S-STS were retrospectively reviewed. Demographics, tumor features, treatment received, and outcomes were analyzed. Results. 103 patients were identified. Median age was 55 years; 53% of patients were female. Tumor site was 39% in trunk, 38% in the lower extremity, 14% in the upper extremity, and 9% in other locations. The most common histology was 36% leiomyosarcoma. Median tumor size was 2.8 cm (range 0.2–14 cm). Sixty-six percent of tumors were of intermediate/high grade. RT was administered preoperatively in 6% of patients and postoperatively in 15% of patients. An R0 resection was accomplished in 92%. At a median follow-up of 34.2 months (range 2.3–176), 9 patients had a LR (8.7%). Tumor size and grade were not associated with LR. OS was not associated with any tumor or patient variables on univariate analysis. Conclusions. LR was low for S-STS, even with large or high grade tumors and selective use of RT. Surgical resection alone may be adequate therapy for most patients. Superficial location seems to supersede other factors imparting a good prognosis for this group of tumors.

Adult sinonasal soft tissue sarcoma: analysis of 48 cases from the French Sarcoma Group database

OBJECTIVE

The aim of this study was to determine the frequency of primary sinonasal adult sarcoma, identify histological subtypes, and analyze prognostic factors.

STUDY DESIGN

Retrospective review.

METHOD

Forty-eight adult sinonasal sarcomas included in the French Sarcoma Group database (Conticabase) were reviewed.

RESULTS

The most frequent tumor types were alveolar rhabdomyosarcoma (33.3%), embryonal rhabdomyosarcoma (14,6%), unclassified sarcoma (14.6%), and leiomyosarcoma (12.5%). All round cell tumors were rhabdomyosarcomas. The 5-year overall survival (OS), metastasis-free survival (MFS), and local recurrence-free survival (LRFS) rates were 62.3%, 73%, and 88.8%, respectively. Histotype was a prognostic factor for OS, MFS, and LRFS, with the worst prognosis associated with rhabdomyosarcomas, regardless of the subtype. The tumor grade influenced the OS and MFS. Surgery was a predictive factor for a complete response.

CONCLUSIONS

These results suggest that sinonasal tract should be considered as an unfavorable site for rhabdomyosarcoma. Moreover, surgery should always be considered in treatment.

MRI, MDCT features, and clinical outcome of extremity leiomyosarcomas: experience in 47 patients

OBJECTIVE

To describe MRI, MDCT features, and clinical outcome of extremity leiomyosarcomas (LMS).

MATERIALS AND METHODS

In this IRB-approved, HIPAA-compliant retrospective study, we included 47 patients (23 women, 24 men; mean age: 55.3 years, range: 17-85 years) with pathologically confirmed extremity LMS seen at our adult tertiary cancer center between 2000 and 2012. MRI/MDCT of primary tumors in 23 patients and follow-up in all patients were reviewed by two radiologists in consensus. Clinical data were extracted from electronic medical records.

RESULTS

Primary tumors were distributed in bones (6 out of 47), deep soft tissues (24 out of 47), and superficial soft tissues (17 out of 47). On imaging (bone = 4, deep soft tissue = 11, superficial soft tissue = 8), compared with skeletal muscle, they were T1 iso-hypointense and T2 hyperintense. Bone LMS were metaphyseal tumors with cortical destruction (3 out of 4). Deep soft-tissue LMS were large with hemorrhage (7 out of 11) and necrosis (10 out of 11). Superficial soft-tissue LMS were relatively smaller, homogeneously enhancing (6 out of 8) tumors. Distant metastases developed in 32 out of 47 patients (bone LMS [6 out of 6], deep soft-tissue LMS [18 out of 24], superficial soft-tissue LMS [8 out of 17]), commonly to lung (29 out of 47) and bone (14 out of 47). At the time of writing, 22 out of 36 patients (bone LMS [4 out of 6], deep soft-tissue LMS [15 out of 24], superficial soft-tissue LMS [4 out of 17]) have died. There was no statistically significant correlation between metastatic disease and tumor size or grade.

CONCLUSION

Extremity LMS arise in bones and in the deep and superficial soft tissues, frequently metastasize to the lungs, and have a poor prognosis. Superficial LMS tend to have a better prognosis than bone or deep soft-tissue LMS.

MRI of superficial soft tissue masses: analysis of features useful in distinguishing between benign and malignant lesions

AIM

To identify the MRI features of superficial soft tissue masses, that may allow differentiation between malignant and non-malignant lesions.

METHOD

A total of 136 consecutive patients referred to a supra-regional musculoskeletal oncology center over a 10-year period with the diagnosis of a superficial soft tissue mass were included in this retrospective study. Features analyzed included patient demographics, lesion size, MRI signal characteristics, margins, lobulation, hemorrhage, necrosis, fascial edema, relationship to the fascia, as well as involvement of the skin. Comparison was then made with the final histological diagnosis.

RESULTS

Of the patients reviewed, 58 were male and 78 were female, and the mean age was 49.9 years. The mean age for malignant lesions was 57.9 years, and that for non-neoplastic and benign conditions 41.9 years (p < 0.001). A significant relationship was identified between malignancy and lobulation (p < 0.01), hemorrhage (p < 0.001), fascial edema (p < 0.001), hemorrhage (p < 0.0001) and necrosis (p < 0.001). The relationship between skin thickening and skin contact and malignancy was also found to be significant. However, size was not found to be an important determining factor for malignancy, with a significant proportion of malignant superficial sarcomas measuring less than 5 cm in maximal diameter.

CONCLUSIONS

This study has shown that a significant proportion of malignant superficial sarcomas measured less than 5 cm in maximal diameter. Fascial edema, skin thickening, skin contact, hemorrhage, and necrosis were found to be highly significant factors indicative of malignancy. Lobulation and peritumoral edema were also significant MRI features.

Superficial soft tissue sarcomas (S-STS): a study of 367 patients from the French Sarcoma Group (FSG) database

AIM

The specific natural history of superficial soft tissue sarcomas (S-STS) has been rarely considered. We describe the clinical characteristics of a large series of S-STS (N=367) from the French Sarcoma Group (GSF-GETO) database and analyse the prognostic factors affecting outcome.

METHODS

We performed univariate and multivariate analyses for overall survival (OS), metastasis-free survival (MFS) and local recurrence-free survival (LRFS).

RESULTS

The median age was 59 years. Fifty-eight percent patients were female. Tumour locations were as follows: extremities, 55%; trunk wall, 35.4%; head and neck, 8% and unknown, 1.6%. Median tumour size was 3.0 cm. The most frequent tumour types were unclassified sarcoma (24.3%) and leiomyosarcoma (22.3%). Thirty-three percent of cases were grade 3. Median follow-up was 6.18 years. The 5-year OS, MFS and LRFS rates were 80.9%, 80.7% and 74.7%, respectively. Multivariate analysis retained histological type and wide resection for predicting LRFS and histological type and grade as prognostic factors of MFS. The factors influencing OS were age, histological type, grade and wide resection. STS with early invasion into but not through the underlying fascia had a significantly poorer MFS than with strict S-STS.

CONCLUSION

S-STS represent a separate category characterised by a better outcome. Adequate surgery, i.e. wide resection, is essential in the management of S-STS.

Metastatic patterns of extremity myxoid liposarcoma and their outcome

BACKGROUND AND OBJECTIVES

Extremity myxoid liposarcomas have a unique extrapulmonary metastatic potential. We studied the metastatic pattern of extremity liposarcomas to determine what types of posttreatment imaging may be of value in the follow-up these patients.

METHODS

Twenty-two patients from a total of 128 patients with primary extremity liposarcoma were treated at a tertiary care institution for subsequent metastases from January 1981 to January 2000. Median follow-up was 45 months (range: 6-270 months). Data on these patients was prospectively collected and then retrospectively analyzed for effect of metastatic pattern and treatment on outcome.

RESULTS

Of these 22 patients, extrapulmonary metastases developed in 10, combined pulmonary and extrapulmonary metastases developed in 6, and isolated pulmonary metastases developed in 6. Of the 16 patients with extrapulmonary metastases, 13 were of the myxoid subtype. Of the 49 patients with extremity myxoid liposarcomas, metastases developed in 14 (29%). The most common sites of metastases among these 14 patients include: the retroperitoneum, 10 patients (71)%; intra-abdominal extra-hepatic, 7 patients (50%); spinal/paraspinal, 6 patients (43%). Only 3 of the patients are alive and disease free and all 3 of these patients are from the subgroup of 10 patients with only extra-pulmonary metastases (2 intra-abdominal and 1 retroperitoneal).

CONCLUSIONS

Extremity myxoid liposarcomas have an unusually high predilection for extra-pulmonary metastases, frequently without any pulmonary metastases. After treatment of the primary tumor, these patients should be followed with periodic chest X-ray and abdominal/pelvic computed tomography (CT) scans. Any back or neurologic complaints should prompt additional imaging of the appropriate spinal area. Consideration should be given to surgical and adjuvant treatment of metastatic disease when appropriate.

Additional wide resection of malignant soft tissue tumors

Forty-five patients with soft tissue sarcomas received additional wide resections after they were treated with simple excision by a primary physician. Of the patients in the current study, 26 were male and 19 were female; all were treated between 1986 and 1998 for malignant soft tissue tumors. The mean followup was 7.1 +/- 3.4 years. The mean time from first excision to additional wide resection was 8 weeks, and for 90% of the patients it was within 12 weeks. In deciding the surgical margin for an additional operation, enhanced computed tomography scans and magnetic resonance images were done. Four (8.8%) patients had local recurrences that required a second resection and had no evidence of disease at latest followup. Four (8.8%) patients had distant metastases but did not have local recurrences. Three patients died of lung metastases. The overall 5-year survival rate of the patients was 93%, and the overall 5-year disease-free rate was 84%. It seems that tumors treated adequately by wide resection in an additional operation have results as good as tumors treated with a primary wide resection.