Prognostic significance of grading and staging systems using MIB-1 score in adult patients with soft tissue sarcoma of the extremities and trunk

Dedifferentiated liposarcoma of the extremities: a Korean multi-center study of 107 cases

BACKGROUND

Dedifferentiated liposarcoma of the extremities (DDL-E) is rare in comparison to that of the retroperitoneum. Its clinical features and surgical principle for resection margins at the dedifferentiated and the well-differentiated components are yet to be elucidated.

METHODS

This retrospective multi-center study examined patients diagnosed with DDL-E from August 2004 to May 2023 at 5 sarcoma centers. Clinical features, oncologic outcomes, and prognostic factors were analyzed.

RESULTS

A total of 107 patients were reviewed. The 5-year local recurrence free survival (LRFS), metastasis-free survival (MFS) and disease specific survival (DSS) were 84.7%, 78.6%, and 87.8%, respectively. Other primary malignancies and extrapulmonary metastasis were observed in 27 and 4 patients, respectively. The independent risk factor for local recurrence was R1/2 margin at the dedifferentiated component of the tumor. Metastasis was associated with tumor size in univariate analysis. The independent risk factor for DSS was tumor grade. Previous unplanned excision, de novo presentation, tumor depth, absence of the well-differentiated component, infiltrative border, R1/2 margin at the well-differentiated component were not associated with oncologic outcomes.

CONCLUSIONS

This is the largest study examining DDL-E to-date. Localized DDL-E has low potential for metastasis and carries an excellent prognosis. Other primary malignancy and extrapulmonary metastasis are more frequent in DDL-E, thus close monitoring of other sites during follow-up is recommended. While wide resection margin is the standard surgical approach for DDL-E, further investigation into moderated wide resection margin at the well-differentiated component is warranted.

Prognostic evaluation of the Ki-67 labeling system in histological grading of non-small round cell sarcoma: a supplementary analysis of a randomized controlled trial, JCOG1306

BACKGROUND

Soft tissue sarcoma (STS) has various histological types and is rare, making it difficult to evaluate the malignancy of each histological type. Thus, comprehensive histological grading is most important in the pathological examination of STS. The Fédération Nationale des Centres de Lutte Contre le Cancer (FNCLCC) grading system is most commonly used in daily pathological analysis of STS. Among the FNCLCC grading system parameters, mitotic count is a key morphological parameter reflecting the proliferative activity of tumor cells, although its reproducibility may be lacking. Here, we compared the prognostic utility of the conventional and modified FNCLCC grading systems in JCOG1306.

METHODS

We analyzed 140 patients with non-small round cell sarcoma. We performed Ki-67 immunostaining using open biopsy specimens before preoperative chemotherapy in all patients. We assessed histological grade in individual cases by conventional FNCLCC grading (tumor differentiation, mitotic count, and necrosis) and modified FNCLCC grading using the Ki-67 labeling index instead of mitotic count. We conducted univariable and multivariable Cox regression analyses to investigate the influence of grade on overall survival.

RESULTS

In univariable analysis, prognosis was worse for patients with conventional FNCLCC Grade 3 tumors compared with Grade 1 or 2 tumors (hazard ratio [HR] 4.21, 95% confidence interval [CI] 1.47-12.05, P = 0.008). Moreover, prognosis was worse in patients with modified FNCLCC Grade 3 tumors compared with Grade 1 or 2 tumors (HR 4.90, 95% CI 1.64-14.65, P = 0.004). In multivariable analysis including both conventional and modified FNCLCC grading, the modified grading more strongly affected overall survival (HR 6.70, 95% CI 1.58-28.40, P = 0.010).

CONCLUSIONS

The modified FNCLCC grading system was superior to the conventional system in predicting the prognosis of patients with non-small round cell sarcoma according to this supplementary analysis of data from the randomized controlled trial JCOG1306.

Case report: The first account of undifferentiated sarcoma with epithelioid features originating in the pleura

Undifferentiated epithelioid sarcoma (USEF) is a rare subtype of undifferentiated soft tissue sarcoma that presents unique challenges in clinical diagnosis and treatment. Here, we report a case of USEF occurring in the pleura of a 51-year-old man for the first time. Thoracoscopic examination revealed widespread nodular changes, and pathological analysis confirmed the presence of numerous epithelioid atypical cells. Immunohistochemical (IHC) analysis demonstrated an undifferentiated phenotype with distinct characteristics: epithelial membrane antigen (foci +), vimentin (+), Ki-67 (+70% +), TTF-1 (+), P53 (mutant type +90%), INI-1 (+), and CK5/6 (small foci +). Immunohistochemical examination of the tumor showed that the tumor was an undifferentiated epithelioid sarcoma. High-throughput DNA sequencing revealed pivotal mutations, including a nonsense mutation in the NF1 gene (c.641A > G(p.H214R)). and critical TP53 missense mutation (c.641A > G(p.H214R)). This TP53 mutation, with a tumor mutation burden of 16.5 Muts/Mb, signifies a high level of genomic instability, likely contributing to the rapid progression and aggressiveness of the disease. Detection of the TP53 mutation provides essential insights, indicating the disease's rapid progression and highlighting the potential for targeted therapies. Although the patient's disease progressed extremely rapidly and he tragically died within a week, we discussed the results of IHC and DNA sequencing in detail and discussed his possible treatment options. Insights gained from this case will be critical in shaping future diagnostic and therapeutic paradigms for USEF, particularly in the context of TP53 mutations.

The efficacy of re-excision after unplanned excision for synovial sarcoma

Background

This investigation studied the clinical features and outcomes of synovial sarcoma (SS) patients from a single institution.

Methods

A retrospective clinicopathologic study was conducted on 129 postoperative SS patients during 2003-2018. Kaplan-Meier curves and Cox proportional hazards regression (Cox) models were performed to determine the parameters associated with recurrence-free survival (RFS), metastasis-free survival (MFS), and cancer-specific survival (CSS) via univariate and multivariate analysis. The impact of unplanned excision (UE) and residual tumor in re-excision specimens was evaluated.

Results

The 3-year RFS, MFS and 5-year CSS were 72 %, 70 %, and 76 %, respectively. Independent factors associated with significantly inferior survival included older age, UE without re-excision, UE with residual tumors, high grade, and deep tumor for RFS, trunk-related tumor, UE without re-excision, UE with residual tumors, and deep tumor for MFS, UE with residual tumors, high grade, and deep tumor for CSS. Re-excision after UE was significantly associated with better RFS (P < 0.001). Residual tumors were remarkably correlated with inferior RFS (P = 0.0012), MFS (P = 0.0016), and CSS (P = 0.048), especially in patients at stage II (MFS: P < 0.001, CSS: P = 0.0014).

Conclusion

UE and residual tumors have a marked impact on the long-term survival of SS patients. Primary wide excision and re-excision is especially essential for patients at stage II.

Review on Lymph Node Metastases, Sentinel Lymph Node Biopsy, and Lymphadenectomy in Sarcoma

Soft tissue sarcomas (STS) originating from connective tissue rarely affect the lymph nodes. However, involvement of lymph nodes in STS is an important aspect of prognosis and treatment. Currently, there is no consensus on the diagnosis and management of lymph node metastases in STS. The key risk factor for nodal involvement is the histological subtype of sarcoma. Radiological and pathological evaluation seems to be the most effective method of assessing lymph nodes in these neoplasms. Thus, sentinel lymph node biopsy (SLNB), which has been shown to be valuable in the management of melanoma or breast cancer, may also be a beneficial diagnostic option in some high-risk STS subtypes. This review summarizes data on the risk factors and clinical characteristics of lymph node involvement in STS. Possible management and therapeutic options are also discussed.

Perivascular epithelioid cell tumors (PEComas) of the bone and soft tissue: a Japanese Musculoskeletal Oncology Group (JMOG) multi-institutional study

PURPOSE

Perivascular epithelioid cell tumors (PEComas) of the bone and soft tissues are rare mesenchymal neoplasms, some of which are malignant. However, their clinical and pathological characteristics remain unclear. This study was performed to investigate the clinical and pathological characteristics of PEComas in bone and soft tissues by leveraging information from the Japanese Musculoskeletal Oncology Group.

METHODS

Nine patients, including four male and five female patients with a median age of 50 years, were retrospectively reviewed. PEComas of the visceral organs, including the uterus and retroperitoneum, were excluded.

RESULTS

Eight tumors arose in the soft tissue and one in the bone, with a mean size of 8.8 cm. Four patients showed local recurrence or distant metastasis. The 1-year survival rate was 78%. Pathologically, eight tumors were classified as malignant and one as having uncertain malignancy potential. Half of the tumors showed high MIB-1 index values of > 30%. Immunohistochemically, the melanocyte marker HMB45 was expressed in 89% of the cases, and muscle-specific markers were expressed only in 30-50% of the cases. Transcription factor binding to IGHM enhancer 3 (TFE3) expression was positive in 100% of the patients. Tumors with high expression of TFE3 were classified as PEComas with malignant potential according to Folpe's classification.

CONCLUSIONS

Bone and soft tissue PEComas may have a higher malignancy potential than other visceral PEComas and are more likely to develop as TFE3-rearranged PEComas.

Diagnostic Performance of Dynamic Contrast-Enhanced MRI and 18F-FDG PET/CT for Evaluation of Soft Tissue Tumors and Correlation with Pathology Parameters

RATIONALE AND OBJECTIVES

To assess the diagnostic performance of dynamic contrast-enhanced (DCE) magnetic resonance imaging (MRI) and fluorine-18-fluorodeoxyglucose (¹⁸F-FDG) positron-emission tomography/computed tomography (PET/CT) parameters in evaluating the biological behavior of soft tissue tumors.

MATERIALS AND METHODS

We retrospectively analyzed DCE-MRI and ¹⁸F-FDG PET/CT parameters in 78 patients with pathology-confirmed soft tissue tumors. A total of 78 patients had undergone DCE-MRI examination, while 24 patients with malignant soft tissue tumor had undergone ¹⁸F-FDG PET/CT examination. Microvessel density (MVD) and the Ki-67 labeling index (LI) were detected using immunohistochemistry. Differences in parameters (Ktrans, Kep, Ve, MVD, and Ki-67 LI) between benign and malignant tumors were compared. Differences in parameters (Ktrans, Kep, Ve, MVD, and SUV_max) between high- and low-proliferation malignant tumors (grouped by Ki-67 LI) were compared. Correlation of the DCE-MRI and ¹⁸F-FDG PET/CT parameters with MVD and Ki-67 LI was analyzed.

RESULTS

Only the Ktrans, Kep, MVD, and Ki-67 LI differed significantly between the benign and malignant soft tissue tumors (all p < 0.001). Only Kep (p = 0.033) and SUV_max (p = 0.001) differed significantly between high- and low-proliferation malignant soft tissue tumors. Ktrans, Kep, and SUV_max correlated positively with MVD (r = 0.805, 0.778, 0.730, respectively; all p < 0.001), and with Ki-67 LI (r = 0.721, 0.685, 0.655, respectively; all p < 0.001).

CONCLUSION

DCE-MRI and ¹⁸F-FDG PET/CT parameters indicate soft tissue tumor biological behavior and can be used to differentiate between benign and malignant soft tissue tumors and between high- and low-proliferation malignant soft tissue tumors.

Soft tissue sarcoma: intravoxel incoherent motion and diffusion kurtosis imaging parameters correlate with the histological grade and Ki-67 expression

BACKGROUND

Accurate prediction of the histological grade and Ki-67 expression of soft tissue sarcoma (STS) before surgery is essential for the subsequent diagnosis, treatment, and prognostic evaluation of patients.

PURPOSE

To evaluate intravoxel incoherent motion (IVIM) and diffusion kurtosis imaging (DKI) in predicting the histological grade and Ki-67 expression of STS.

MATERIAL AND METHODS

A total of 40 patients underwent 3-T MRI, including conventional sequences; IVIM and DKI parameters were obtained. All patients were divided into a low-grade (grade 1 and grade 2) group and a high-grade (grade 3) group through pathological analysis. Ki-67 expression of each lesion was calculated. Chi-square test, independent sample t-test, Mann-Whitney U test, Pearson, Spearman, and receiver operating characteristic curve analysis were performed.

RESULTS

There were 17 patients in the low-grade group and 23 in the high-grade group. Ki-67 expression was in the range of 10%-80%. D value was inversely correlated with Ki-67 expression. MK value showed a moderate positive correlation with Ki-67 expression. Regarding histological grading, only the peritumoral enhancement was statistically different between low- and high-grade STS on conventional MRI (P=0.024). The high-grade group had significantly higher MK value and lower D and MD value than the low-grade group. MK value showed the best diagnostic performance. The combination of MK and MD yielded the highest specificity (88.24%), and the combination of D, MK, and MD yielded the best area under the curve value (0.841) and sensitivity (95.65%).

CONCLUSION

IVIM and DKI parameters were correlated with Ki-67 expression and could help differentiate between low- and high-grade STS.

Correlation between quantitative parameters of CEUS and Ki-67 labeling index in soft-tissue sarcoma

BACKGROUND

Apart from the immunohistochemical Ki-67 labeling index (LI), clinicians need a non-invasive and convenient way to predict the prognosis of patients with soft-tissue sarcoma (STS).

PURPOSE

To investigate the correlation between quantitative parameters of contrast-enhanced ultrasound (CEUS) and Ki-67 LI in STS.

MATERIAL AND METHODS

A total of 25 patients diagnosed with STS who underwent CEUS examination using SonoVue®, between January 2019 to November 2020, were included in the study. They were then divided into a high-proliferation group and low-proliferation group according to 30% Ki-67 positive tumor cells. The quantitative parameters in the semi-automatic time intensity curve analysis software, including arrival time, time to peak, peak intensity, rise time (RT), rise slope, 50% wash-out time, and 50% wash-out intensity, were extracted from the time intensity curve of CEUS by two independent observers. Statistical evaluation of the correlation and difference between CEUS quantitative parameters and Ki-67 LI between the two groups was performed. According to the area under the curve (AUC) analysis, optimal cutoff points of parameters with significant difference were determined.

RESULTS

CEUS RT of the high-proliferation group in STS was significantly higher than that of the low-proliferation group (ρ = 0.509, P = 0.01). The most reasonable cutoff to distinguish between low- and high-proliferation groups was 10.84 s. The sensitivity, specificity, and the AUC were 86.7%, 80%, and 0.80, respectively.

CONCLUSION

CEUS RT was correlated with Ki-67 LI of STS, which can be used as a minimally invasive auxiliary tool to predict the prognosis of STS in clinical practice.

Atypical spindle cell/pleomorphic lipomatous tumor with a sarcomatous component showing high mitotic activity and Ki-67 labeling index: report of a unique case mimicking dedifferentiated liposarcoma

Atypical spindle cell/pleomorphic lipomatous tumor (ASPLT) is a new entity of benign adipocytic tumor that spans a wide spectrum of histology from adipocytic to spindle cell/pleomorphic tumors. The latter non-adipocytic component rarely shows sarcomatous features although ASPLTs are not thought to dedifferentiate. A 78-year-old woman with ASPLT in the left thigh had a sarcomatous component with high mitotic activity and Ki-67 labeling index (LI) mimicking dedifferentiated liposarcoma. The adipocytic component consisted of various-sized adipocytic cells with few lipoblasts. The sarcomatous component consisted of a fascicular proliferation of atypical spindle cells with scattered large bizarre and multinucleated giant cells. Mitotic figures including atypical mitoses were frequently observed. Immunohistochemically, the tumor cells were positive for cluster of differentiation 34 but not mouse double minute 2 homolog (MDM2), cyclin-dependent kinase 4 (CDK4), or retinoblastoma (Rb) protein. Ki-67 LI in the sarcomatous component reached 40%. MDM2 and CDK4 genes were not amplified and 13q14 including the RB1 locus was deleted according to fluorescence in situ hybridization. The patient is alive with no evidence of local recurrence or distant metastasis 3.5 years after surgery. As ASPLT may exhibit morphological variation, it is important to rule out dedifferentiated liposarcoma with careful pathological examination.

Prognostic usefulness of a modified risk model for solitary fibrous tumor that includes the Ki-67 labeling index

Background

Predicting the prognosis of patients with solitary fibrous tumor (SFT) is often difficult. The prognostic risk models developed by Demicco et al. are now the standard for evaluating the risk of SFT metastasis in the current World Health Organization classification of soft tissue and bone tumors.

Methods

In this study, we examined the prognostic usefulness of a modified version of the Demicco risk models that replaces the mitotic count with the Ki-67 labeling index. We compared the three-variable and four-variable Demicco risk models with our modified risk models using Kaplan–Meier curves based on data for 43 patients with SFT.

Results

We found a significant difference in metastasis-free survival when patients were classified into low-risk and intermediate/high-risk groups using the three-variable (P = 0.022) and four-variable (P = 0.046) Demicco models. There was also a significant difference in metastasis-free survival between the low-risk and intermediate/high-risk groups when the modified three-variable (P = 0.006) and four-variable (P = 0.022) models were used.

Conclusion

Modified risk models that include the Ki-67 labeling index are effective for prediction of the prognosis in patients with SFT.

Visual Counting and Automated Image-analytic Assessment of Ki-67 and their Prognostic Value in Synovial Sarcoma

BACKGROUND

Ki-67 is a widely used proliferation marker reflecting prognosis in various tumors. However, visual assessment and scoring of Ki-67 suffers from marked inter-observer and intra-observer variability. We aimed to assess the concordance of manual counting and automated image-analytic scoring methods for Ki-67 in synovial sarcoma.

PATIENTS AND METHODS

Tissue microarrays from 34 patients with synovial sarcoma were immunostained for Ki-67 and scored both visually and with 3DHistech QuantCenter.

RESULTS

The automated assessment of Ki-67 expression was in good agreement with the visually counted Ki-67 (r _Pearson =0.96, p<0.001). In a Cox regression model automated [hazard ratio (HR)=1.047, p=0.024], but not visual (HR=1.063, p=0.053) assessment method associated high Ki-67 scores with worse overall survival.

CONCLUSION

The automated Ki-67 assessment method appears to be comparable to the visual method in synovial sarcoma and had a significant association to overall survival.

Ki-67 immunoexpression and radiological assessment of necrosis improves accuracy of conventional and modified core biopsy systems in predicting the final grade assigned to adult-soft tissue sarcomas. An international collaborative study

Based on the French Federation Nationale des Centers de Lutte Contre le Cancer (FNCLCC) grading system, this study assesses the accuracy of conventional and modified core biopsy (CB) systems in predicting the final grade (low vs high) assigned to the resected specimen. Substituting Ki-67 immunoexpression for mitotic count, and radiological for histological assessment of necrosis, we used two modified FNCLCC CB grading systems: (1) Ki-67 immunoexpression alone, and (2) Ki-67 plus radiological assessment of necrosis. We graded 199 soft tissue sarcomas (STS) from nine centers, and compared the results for the conventional (obtained from local histopathology reports) and modified CB systems with the final FNCLCC grading of the corresponding resected specimens. Due to insufficient sample quality or lack of available radiologic data, five cases were not evaluated for Ki67 or radiological assessment of necrosis. The conventional FNCLCC CB grading system accurately identified 109 of the 130 high-grade cases (83.8%). The CB grading matched the final FNCLCC grading (low vs high) in 175 (87.9%) of the 199 resected tumors; overestimating the final grade in three cases and underestimating in 21 cases. Modified system 1 (Ki-67) accurately identified 117 of the 130 high-grade cases (90.0%). The CB grading matched the final FNCLCC grading (low vs high) in 175 (89.7%) of the 195 evaluated cases; overestimating seven and underestimating 13 cases. Modified system 2 (Ki-67 plus radiological necrosis) accurately identified 120 of the 130 high-grade cases (92.3%). This last matched the final FNCLCC grading (low vs high) in 177 (91.2%) of the 194 evaluated cases; overestimating seven and underestimating 10 cases. Modified system 2 obtained highest area under ROC curves, although not statistically significant. Underestimated CB grades did not correlate with histological subtypes, although many of the discrepant cases were myxoid tumors (myxofibrosarcomas or myxoid liposarcomas), leiomyosarcomas or undifferentiated pleomorphic/spindle cell sarcomas. Using modified FNCLCC CB grading systems to replace conventional mitotic count and histologic assessment of necrosis may improve the distinction between low and high-grade STS on CB. Our study confirms that classifying grade 1 as low grade and grades 2 and 3 as high grade improves correlation between CB and final grade by up to 21%, irrespective of CB system used. A higher than expected Ki-67 score in a low-grade sarcoma diagnosed on CB should raise concern that a higher-grade component may not have been sampled. Furthermore, correlation of all clinicopathological and radiological findings at multidisciplinary meetings is essential to assess the histological grade on CB as accurately as possible.

Case Analysis of 14 Children with Malignant Rhabdoid Tumor of the Kidney

Objective

This study aims to summarize the clinical features and prognoses of the malignant rhabdoid tumor of the kidney (MRTK) in children. It further aims to analyze the high-risk factors affecting MRTK prognosis.

Methods

Clinical data from 14 children with MRTK treated in Paediatrics of Beijing Tongren Hospital from January 2010 to December 2019, along with the high-risk factors affecting prognosis, were retrospectively analyzed.

Results

There were 14 children with MRTK included in the study, with a median onset age of 13 (3–46) months. Thirteen patients had distant metastases, the most common site for metastases being inside the lung. A comprehensive treatment protocol combined with chemotherapy was mainly applied during the surgery. A surgical resection of primary tumors was performed on 13 (13/14) patients, and all 14 children received chemotherapy with ifosfamide + carboplatin + etoposide, ifosfamide + etoposide, and vincristine + pirarubicin + cyclophosphamide regimens, alternately. Three patients received radiotherapy and two received oral targeted drugs after partial response. The median follow-up was after 16.5 months (3–53 months) and the four-year overall survival (OS) was 41.8%. In children aged ≤24 months and children aged >24 months, the two-year OS was 67.2% and 100% (χ² = 108.998, P<0.05), respectively. In children with Ki 67 > 70% and children with Ki 67 < 70%, the two-year OS was 52.6% and 86.9% (χ² = 8.544, P = 0.003), respectively. In children with distant metastases and children without distant metastasis, the two-year OS was 70% and 100% (χ² = 14.239, P<0.05), respectively.

Conclusion

The most common MRTK distant metastasis site is the lung. Risk factors for poor MRTK prognoses include an age of <24 months, Ki 67 > 70%, and distant metastases.

Retroperitoneal tumors: Review of diagnosis and management

Retroperitoneal tumors are extremely rare tumors occurring in the retroperitoneum. Retroperitoneal tumors are divided into benign tumors and malignant tumors, including retroperitoneal sarcoma. Approximately 70-80% of primary retroperitoneal soft-tissue tumors are malignant; however, these only account for 0.1-0.2% of all malignancies. Retroperitoneal sarcoma is an orphan malignant disease with a low incidence. The information on benign retroperitoneal tumors is limited. The American Joint Committee on Cancer/TNM classification updated to the 8th edition in 2017. In 2010, three new drugs for soft tissue sarcoma were approved based on the results of phase III trials, but the histological subtypes of the patients enrolled in the trials of each drug differed. Recently, in addition to surgery for retroperitoneal sarcoma, the effectiveness of perioperative radiation therapy has become interesting. For malignant retroperitoneal tumors and retroperitoneal sarcoma, survival improvement and locoregional recurrence prevention can be undertaken by carrying out surgery to secure negative margins with wide and combined resection of some adjacent organs, and cooperation with a trained medical team comprising of radiologists, pathologists and medical oncologists in centralized hospitals. Some clinical trials aimed at further improving treatment results by adding preoperative chemotherapy and radiation therapy based on histological confirmation using a correct needle biopsy are in progress. In recent years, molecular profiling has been used to select eligible patients for chemotherapy. In the future, precision medicine with next-generation sequencing technology will be expected among the diverse and potential future treatments for retroperitoneal sarcoma. In this review, we summarized the current state of retroperitoneal tumors and retroperitoneal sarcoma.

Soft tissue sarcoma: DWI and DCE-MRI parameters correlate with Ki-67 labeling index

OBJECTIVES

To examine the correlation of diffusion-weighted and dynamic contrast-enhanced magnetic resonance imaging (MRI) parameters with Ki-67 labeling index (LI) in soft tissue sarcoma (STS).

METHODS

The institutional review board approved this retrospective study, and the requirement for informed consent was waived. Thirty-six patients with STS who underwent 3.0-T MRI, including diffusion-weighted and dynamic contrast-enhanced MRI, between July 2011 and February 2018, were included in this study. The mean and minimum apparent diffusion coefficients (ADCs) (ADC_mean and ADC_min, respectively), volume transfer constant, reflux rate, and volume fraction of the extravascular extracellular matrix of each lesion were independently analyzed by two readers. Their relationship with the Ki-67 LI was examined using Spearman's correlation analyses. Differences between low- and high-proliferation groups based on Ki-67 LI were evaluated statistically. Optimal cut-off points were determined using the area under the curve analysis for significant parameters. Interobserver agreement was assessed with the intraclass correlation coefficient.

RESULTS

ADC_mean (ρ = - 0.333, p = 0.047) was significantly and inversely correlated with Ki-67 LI. The high-proliferation group showed a significantly lower ADC_mean than did the low-proliferation group (median, 1.08 vs. 1.20; p = 0.048). When a cut-off ADC_mean value of 1.16 × 10^-3 mm²/s was used, the sensitivity, specificity, and area under the curve for differentiating low- and high-proliferation groups were 75.0%, 60.0%, and 0.712, respectively. Interobserver agreements between the two readers were almost perfect for all parameters.

CONCLUSIONS

ADC_mean was correlated with Ki-67 LI and could help differentiate between STS with low and high proliferation potential.

KEY POINTS

• ADC _meanwas significantly and inversely correlated with Ki-67 labeling index in soft tissue sarcoma. • In the high-proliferation group, ADC _meanvalues were significantly lower than those of the low-proliferation group.

Texture analysis parameters derived from T1-and T2-weighted magnetic resonance images can reflect Ki67 index in soft tissue sarcoma

BACKGROUND AND OBJECTIVES

Texture analysis derived from morphological magnetic resonance (MR) images might be associated with histopathology in tumors. The present study sought to elucidate possible associations between texture features derived from T1-and T2-weighted images with proliferation index Ki67 in soft tissue sarcomas.

METHODS

Overall, 29 patients (n = 13, 44.8% female) with a median age of 52 years were included into this retrospective study. Several soft tissue sarcomas were investigated. Texture analysis was performed on pre-contrast T1-weighted and T2-weighted images using the free available Mazda software.

RESULTS

The best correlation coefficients with Ki67 index were identified for the following parameters: T1-weighted images "45dgr_RLNonUni (p = 0.50, P = 0.006), T2-weighted images "S (4,0)SumAverg" (p = -0.45, P = 0.02). A ROC analysis was performed for Ki67-index with a threshold of 10%. The highest area under the curve (AUC) was found for the parameter "T1_WavEnHL_s-7" with an AUC of 0.90. For the threshold of Ki67 = 20% the highest AUC was identified for the parameter "T2_S (1,1)Entropy" with an AUC of 0.77.

CONCLUSION

Several texture features derived from T1-and T2-weighted images correlated with proliferation index Ki67 and might be used as valuable novel biomarkers in soft tissue sarcomas.

Assessment of Expression of Ki-67 in Benign and Malignant Prostatic Lesions among Sudanese Patients

BACKGROUND

Prostatic cancer is one of the most common cancers of males in a Sudanese population. The early detection is very important, as it is only curable at an early stage.

AIM

The objective of this study was to investigate the expression pattern of Ki-67 in benign and malignant prostatic lesions to improve the diagnosis that may help in better management and prevention of disease.

MATERIAL AND METHODS

Fifty-eight formalin fixed paraffin blocks from diagnosed cases of prostatic tumours with different grade, and stages were included in this study. Ki-67 expression was examined immunohistochemically by using monoclonal mouse anti-human Ki67 IS626. The results were correlated with Gleason score and tumour differentiation and stage.

RESULTS

The frequency of histological types was as follow: 11 cases of benign prostate, atic hyperplasia (19%) and 47 cases of prostatic cancer (81%). Our results stated that prostatic adenocarcinoma among Sudanese patients was of low grade which means tumours are less aggressive. Furthermore, the findings demonstrate that Ki-67 expression in prostatic carcinoma smears was correlated significantly with the degree of Gleason score (P < 0.05).

CONCLUSIONS

We found that the prostatic adenocarcinoma among Sudanese patients was less aggressive. Furthermore, Ki-67 expression was proportional to the grade of a tumour and it was a useful prognostic and diagnostic biomarker.

High cyclin A expression, but not Ki67, is associated with early recurrence in desmoid tumors

BACKGROUND AND OBJECTIVES

Desmoid tumors are soft-tissue tumors originating from myofibroblasts with a tendency to recur after surgery. High expression of proliferation markers is associated with shortened progression-free and/or overall survival in many neoplasms, including soft-tissue sarcomas. We investigated the prognostic role of cyclin A and Ki67 in desmoid tumors by immunohistochemistry.

METHODS

The study included 76 patients with desmoid tumor operated at Helsinki University Hospital between 1987 and 2011. A tissue micro array (TMA) was constructed and the TMA sections were immunostained with cyclin A and Ki67 antibodies. A computer-assisted image analysis was performed.

RESULTS

Cyclin A expression was evaluable in 74 and Ki67 in 70 patients. Cyclin A immunopositivity varied from 0% to 9.9%, with a mean of 1.9%. Cyclin A expression correlated significantly with Ki67. Cyclin A expression was associated with recurrence-free survival (HR 1.9, 95% CI = 1.1-3.2, P = .02), as were positive margin (HR 6.0, 95% CI = 1.6-22.5, P = .008) and extremity location (HR 5.3, 95% CI = 1.7-16.8, P = 0.005). Ki67 immunopositivity varied from 0.33% to 13.8%, with a mean of 4.6%, but had no significant prognostic impact (HR 1.1, P = .2).

CONCLUSIONS

Our study indicates that cyclin A may be a new prognostic biomarker in surgically treated desmoid tumors.

Aquaporin-1 and -5 are involved in the invasion and proliferation of soft tissue sarcomas

BACKGROUND AND AIM

Recent studies of several carcinomas have reported that aquaporin possesses novel oncogenic properties. The aim of this study was to clarify the involvement of aquaporin-1 and -5 in the proliferation, invasion and metastasis of soft tissue sarcomas.

MATERIALS AND METHODS

The expression of aquaporin-1 and -5 was immunohistochemically examined in 73 soft tissue sarcomas as well as in benign, locally aggressive soft tissue tumors, and in soft tissues of adult humans and human fetuses. The mRNA and protein expression of aquaporin-1 and -5 genes were quantified in 19 sarcoma tissues.

RESULTS

Aquaporin-1 was expressed in the tumor cells of 37 (51%) and aquaporin-5 in 29 (40%) of 73 soft tissue sarcomas. Two expression patterns were identified: a differentiation-dependent pattern, similar to their expression in adult human soft tissue and in benign soft tissue tumors, and an aggressiveness-related pattern, that is similar to their expression in the mesenchymal cells of the developing fetal limb. The latter expression pattern proved to be an independent prognostic factor for patients with soft tissue sarcoma, in which aquaporin-1 was related to the invasiveness, and aquaporin-5 to the proliferation of soft tissue sarcoma cells.

CONCLUSION

These results indicate pivotal roles for aquaporin-1 and -5 in the aggressive growth and metastatic potential of soft tissue sarcomas, suggesting that they are promising targets for the treatment of patients with intractable soft tissue sarcoma.

Clinicopathological significance of glucose transporter protein-1 overexpression in human osteosarcoma

Although previous studies have demonstrated that Glut-1 is the predominant glucose transporter, is significantly overexpressed in various types of tumor and is correlated with poor prognosis, the potential function and clinical value of Glut-1 expression in osteosarcoma remains largely unclear. In particular, the prospective associations between Glut-1 expression levels and clinicopathological factors remains to be elucidated. In the present study, immunohistochemistry was performed to detect Glut-1 protein expression in 51 paired osteosarcoma specimens and adjacent non-cancerous tissues, and reverse transcription-quantitative polymerase chain reaction analysis was performed to examine Glut-1 mRNA expression levels in 6 pairs of these tissues. Statistical analyses were conducted to determine the associations between Glut-1 expression and various clinicopathological parameters. Glut-1 protein was revealed to be overexpressed in 38 (74.5%) osteosarcoma tissues, but only in 6 (11.8%) adjacent non-cancerous tissues. Glut-1 mRNA levels were also upregulated in osteosarcoma tissues compared with adjacent non-cancerous tissues. While there were no clear statistical relationships between Glut-1 expression and patient sex, resection, tumor location, size, T stage and adjuvant treatment, Glut-1 expression levels were significantly associated with age, tumor-node-metastasis stage, lymph node metastasis and survival. The median survival time in patients with low Glut-1 expression levels was longer than in patients with a high expression level. Glut-1 was significantly overexpressed in osteosarcoma tissues, and Glut-1 expression was associated with clinicopathological factors which upregulate the invasion and metastasis of osteosarcoma, and may be a potential predictor of survival in patients with osteosarcoma.

Federation Nationale des Centers de Lutte Contre le Cancer grading of soft tissue sarcomas on needle core biopsies using surrogate markers

Needle core biopsy (NCB) of soft tissue sarcomas (STSs) presents problems for French Federation Nationale des Centers de Lutte Contre le Cancer (FNCLCC) histological grading because small sample size hinders determination of necrosis and mitotic activity. We graded 53 STSs on NCB using a modified FNCLCC grading system that substitutes Ki-67 immunoexpression for mitotic count and uses a radiological assessment of necrosis, and compared the results with those obtained by conventional FNCLCC grading of the corresponding untreated, surgically resected specimen. Forty-eight of the 53 tumors were classified as malignant on NCB (concordance = 91%). The modified FNCLCC grade correctly separated high-grade (grades II and III) from low-grade sarcomas in 70% of cases and predicted the traditional FNCLCC grade given to the resected specimen in 49% of cases. Ki-67 scores of 2 or 3 were observed in 5 tumors classified as low-grade neoplasms on NCB but upgraded to a high-grade dedifferentiated liposarcoma on resection. Underestimated NCB grades were commonly encountered with lipomatous tumors due to sampling error, whereas Ki-67 or radiologic necrosis scores higher than the corresponding histological scores were responsible for the vast majority of overestimated NCB grades. Our FNCLCC grading scheme replacing conventional mitosis counting and histologic assessment of necrosis with surrogate markers is useful in separating high- and low-grade STSs on NCB for STS treatment planning. High Ki-67 rate should raise suspicion of a higher-grade component, particularly with fatty tumors.

Prospective evaluation of Ki-67 system in histological grading of soft tissue sarcomas in the Japan Clinical Oncology Group Study JCOG0304

Background

The correct clinical staging of soft tissue sarcomas (STS) is critical for the selection of treatments. The staging system consists of histological grade of the tumors and French Federation of Cancer Center (FNCLCC) system based on mitotic count is widely used for the grading. In this study, we compared the validity and usefulness of Ki-67 grading system with FNCLCC system in JCOG0304 trial which investigated the efficacy and safety of perioperative chemotherapy with doxorubicin and ifosfamide for STS.

Methods

All 70 eligible patients with STS in the extremities treated by perioperative chemotherapy in JCOG0304 were analyzed. Univariate and multivariate Cox regression analyses were conducted to investigate an influence on overall survival.

Results

The reproducibility of Ki-67 grading system in the histological grading of STS was higher than FNCLCC system (κ = 0.54 [95 % CI 0.39–0.71], and 0.46 [0.32–0.62], respectively). Although FNCLCC grade was not associated with overall survival (OS) in univariate analysis (HR 2.80 [0.74–10.55], p = 0.13), Ki-67 grading system had a tendency to associate with OS in univariate analysis (HR 4.12 [0.89–19.09], p = 0.07) and multivariate analysis with backward elimination (HR 3.51 [0.75–16.36], p = 0.11).

Conclusions

This is the first report demonstrating the efficacy of Ki-67 grading system for the patients with STS in the prospective trial. The results indicate that Ki-67 grading system might be useful for the evaluation of histological grade of STS.

Quality of Life, Physical and Mental Status and Contentment of Patients with Localized Soft Tissue or Bone Sarcoma: A Questionnaire Analysis

Extremity soft tissue and bone sarcomas represent a rare group of bone and connective tissue cancers. In literature, there is little information about psycho-emotional status and impact on quality of life after the diagnosis and treatment of this kind of tumors. The aim of this survey was to define the profile of the patients at risk and their need for psychooncological care. Our self-created questionnaire consists of 71 items related to the individual emotional, mental and physical situation after the diagnosis of soft tissue and bone sarcoma. Sixty-six patients, surgically treated at our department, were included. Only 37.5% of the patients considered themselves to be completely emotional stable. Psychooncological treatment was accepted mostly by female patients, by patients with higher education level and by married patients. Emotional stability and confidence in future were associated with a strong familiar background, with numerous consultations of psychooncological service and also to gender and physical condition. Current quality of life was strongly correlated to physical condition. Thanks to our questionnaire, we disclosed few risk factors for negative emotional outcome after therapy, such as higher age, social isolation, female gender and poor physical status.

Cytoplasmic maspin expression predicts poor prognosis of patients with soft tissue sarcomas

BACKGROUND

Maspin is a 42 kDa protein known to act as a tumor suppressor. Although its function has not been fully elucidated, numerous reports have investigated the prognostic impact of maspin in patients with several types of cancer. However, there have been no reports on the association between maspin expression and the prognosis of patients with soft tissue sarcomas (STS). The aim of this study was thus to explore the association of maspin expression with the prognosis of patients with STS.

METHODS

One-hundred and eight paraffin-embedded STS tissue samples were immunohistochemically analyzed using antibodies for maspin and Ki-67 antigen. The patients were followed up for 1 to 300 months (median: 33 months) and the prognostic value was evaluated by log-rank test and Cox's regression hazard model.

RESULTS

Cytoplasmic maspin expression was observed in 48.1% of specimens, and was significantly correlated with a higher FNCLCC grade (P = 0.002) and the presence of distant metastases (P = 0.001), and those with cytoplasmic maspin expression had both shorter disease-free survival (DFS) and overall survival (OS) by log-rank test (P <0.001, P = 0.001, respectively). By Cox's multivariate analysis, the presence of distant metastases was the only prognostic factor for DFS and OS.

CONCLUSIONS

This is the first report to reveal an association between maspin expression and the prognosis of patients with STS. Although further studies with a larger series of patients and a longer follow-up period will be needed, cytoplasmic maspin expression could be an indicator of unfavorable prognosis in patients with STS.

VIRTUAL SLIDES

The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/13000_2014_205.

Grading of soft tissue sarcomas: from histological to molecular assessment

Several histological grading systems for soft tissue sarcomas have been described since the early 1980s. Their main objective is to select patients for adjuvant chemotherapy. Two histological grading systems are used in daily practice, the National Cancer Institute (NCI) and the French Federation of Cancer Centers Sarcoma Group (FNCLCC) systems. They have been devised by combining histological parameters: number of mitoses per high-power field, the presence of necrosis, cellular and nuclear morphology and the degree of cellularity for the NCI grading; and tumour differentiation, mitotic index and extent of necrosis for the French system. Histological grading is far more appropriate to assess the risk of metastasis. However, several limitations prevent its use: grade cannot be applied to all histological types, its reproducibility is not perfect, a three-grade system generates an intermediate grade with undetermined prognosis, and finally the core needle biopsy, now widely used for the diagnosis of soft tissue sarcoma, is not the best sample to assess the grade. The development of molecular grading in addition to histological grading probably represents the next step. Molecular signatures based on quantitative evaluation of chromosomal complexity such as CINSARC (complexity index in sarcomas) appear as a strong independent predictive factor for metastasis in several types of sarcoma, and even in several other types of cancer. When they can be instituted in daily practice on formalin fixed, paraffin embedded material, molecular signatures will not only provide information on risk of metastasis, but also better understanding of cancer development, response or resistance to evaluated drugs, and potential targets for future treatments.

[Malignant fibrous histiocytoma/undifferentiated pleomorphic sarcoma of the penis: a case report]

We report the case of a malignant fibrous histiocytoma/undifferentiated pleomorphic sarcoma (MFH/UPS) of the penis in a 78-years-old-man who had undergone previous radical prostatectomy, external beam radiation therapy for prostatic adenocarcinoma. The mass was a 9-cm firm lesion at the base of the penis predominantly composed of malignant spindle cells arranged in sweeping fascicles and storiform pattern. The tumor cells stained for vimentin, beta-smooth muscle actin, S-100, and were negative for keratin, desmin, Melan A, PSA. Despite total penectomy, he developed a local reccurence 4 months after surgery, and died from dissemination 6 months after surgery. This is the 8th case of penile MFH/UPS.

Variable Ki67 proliferative index in 65 cases of nodular fasciitis, compared with fibrosarcoma and fibromatosis

Abstract

Nodular fasciitis is the most common pseudosarcomatous lesion of soft tissue. Ki67 was considered as a useful marker for distinguishing some benign and malignant lesions. To study the usefulness of Ki67 in diagnosis of nodular fasciitis, the expression of Ki67 was examined by using immunostaining in 65 nodular fasciitis specimens, 15 desmoid fibromatosis specimens and 20 fibrosarcoma specimens. The results showed that there was a variable Ki67 index in all 65 cases of nodular fasciitis, and the mean labeling index was 23.71±15.01%. In majority (70.77%) of all cases,the index was ranged from 10% to 50%, in 6.15% (4/65) of cases the higher Ki67 index (over 50%) could be seen. The Ki67 proliferative index was closely related to duration of lesion, but not to age distribution, lesion size, sites of lesions and gender. Moreover, the mean proliferative index in desmoid fibromatosis and fibrosarcoma was 3.20±1.26% and 26.15±3.30% respectively. The mean Ki67 index of nodular fasciitis was not significantly lower than fibrosarcoma, but higher than desmoid fibromatosis. The variable and high Ki67 index in nodular fasciitis may pose a diagnostic challenge. We should not misdiagnose nodular fasciitis as a sarcoma because of its high Ki67 index. The recurrence of nodular fasciitis is rare; and the utility of Ki67 immunostaining may be not suitable for recurrence assessment in nodular fasciitis.

Virtual slides

The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/4782335818876666

Poorly differentiated synovial sarcoma is associated with high expression of enhancer of zeste homologue 2 (EZH2)

Background

Enhancer of zeste homologue 2 (EZH2) is a polycomb group (PcG) family protein. Acting as a histone methyltransferase it plays crucial roles in maintaining epigenetic stem cell signature, while its deregulation leads to tumor development. EZH2 overexpression is commonly associated with poor prognosis in a variety of tumor types including carcinomas, lymphomas and soft tissue sarcomas. However, although the synovial sarcoma fusion proteins SYT-SSX1/2/4 are known to interact with PcG members, the diagnostic and prognostic significance of EZH2 expression in synovial sarcoma has not yet been investigated. Also, literature data are equivocal on the correlation between EZH2 expression and the abundance of trimethylated histone 3 lysine 27 (H3K27me3) motifs in tumors.

Methods

Immunohistochemical stains of EZH2, H3K27me3, and Ki-67 were performed on tissue microarrays containing cores from 6 poorly differentiated, 39 monophasic and 10 biphasic synovial sarcomas, and evaluated by pre-established scoring criteria. Results of the three immunostainings were compared, and differences were sought between the histological subtypes as well as patient groups defined by gender, age, tumor location, the presence of distant metastasis, and the type of fusion gene. The relationship between EZH2 expression and survival was plotted on a Kaplan-Meier curve.

Results

High expression of EZH2 mRNA and protein was specifically detected in the poorly differentiated subtype. EZH2 scores were found to correlate with those of Ki-67 and H3K27me3. Cases with high EZH2 score were characterized by larger tumor size (≥ 5cm), distant metastasis, and poor prognosis. Even in the monophasic and biphasic subtypes, higher expression of EZH2 was associated with higher proliferation rate, larger tumor size, and the risk of developing distant metastasis. In these histological groups, EZH2 was superior to Ki-67 in predicting metastatic disease.

Conclusions

High expression of EZH2 helps to distinguish poorly differentiated synovial sarcoma from the monophasic and biphasic subtypes, and it is associated with unfavorable clinical outcome. Importantly, high EZH2 expression is predictive of developing distant metastasis even in the better-differentiated subtypes. EZH2 overexpression in synovial sarcoma is correlated with high H3K27 trimethylation. Thus, along with other epigenetic regulators, EZH2 may be a future therapeutic target.

Prediction of treatment outcomes in patients with chest wall sarcoma: evaluation with PET/CT

OBJECTIVE

The aim of this study was to investigate the prognostic implications of (18)F-2-fluoro-2-deoxy-d-glucose positron emission tomography/computed tomography in patients with chest wall sarcoma.

METHODS

Positron emission tomography/computed tomography scans of 42 patients (mean age: 46 years) with chest wall sarcomas were analyzed. Pathologic confirmation was obtained by surgical specimens in all patients. Tumor grade assessed by Ki-67 (MIB-1) immunohistochemical analysis and expression of glucose transporter protein 1 were compared with a maximum standardized uptake value. Univariate and multivariate analyses were conducted for estimates of overall and event-free survivals.

RESULTS

The median maximum standardized uptake value of the tumor was 10.2 and the median MIB-1 index of the tumor was 32.5%. Glucose transporter protein 1 expression was found in 29 patients (69%). Univariate analyses revealed that surgery, chemotherapy, MIB-1 labeling index (cut-off 32.5%), MIB-1 grade, glucose transporter protein 1 expression and maximum standardized uptake value were possible predictors for overall and event-free survival. Multivariate analysis revealed that surgery (hazard ratio, 4.852; P = 0.017), maximum standardized uptake value (hazard ratio, 3.077; P = 0.037) and MIB-1 labeling index (hazard ratio, 6.549; P = 0.003) were independent predictors of event-free survival. In addition, surgery (hazard ratio, 4.092; P = 0.021) and maximum standardized uptake value (hazard ratio, 2.968; P = 0.027) were independent predictors of overall survival.

CONCLUSIONS

(18)F-2-fluoro-2-deoxy-d-glucose positron emission tomography/computed tomography allows the prediction of prognosis after treatment in patients with chest wall sarcoma and may be useful in selecting high-risk patients for more risk-adapted treatments.

Prognostic value of proliferation in pleomorphic soft tissue sarcomas: a new look at an old measure

Though proliferation has repeatedly shown a prognostic role in sarcomas, it has not reached clinical application. We performed a comprehensive evaluation of the prognostic role of 5 proliferation measures in a large series of soft tissue sarcomas of the extremities and the trunk wall. One hundred ninety-six primary soft tissue sarcomas of the extremities and the trunk wall were subjected to DNA flow cytometry for quantification of S-phase fraction and to immunohistochemical evaluation of Ki-67, Top2a, p21, and p27Kip1. In univariate analysis, positive expression of Ki-67 (hazard ratio = 4.5, CI = 1.6-12.1), Top2a (hazard ratio = 2.2, CI = 1.2-3.5) and high S-phase fraction (hazard ratio = 1.8, CI = 1.2-3.7) significantly correlated with risk for metastasis. When combined with currently used prognostic factors, Ki-67, S-phase fraction and Top2a fraction contributed to refined identification of prognostic risk groups. Proliferation, as assessed by expression of Ki-67 and Top2a and evaluation of S-phase fraction and applied to statistical decision-tree models, provides prognostic information in soft tissue sarcomas of the extremity and trunk wall. Though proliferation contributes independently to currently applied prognosticators, its role is particularly strong when few other factors are available, which suggests a role in preoperative decision-making related to identification of high-risk individuals who would benefit from neoadjuvant therapy.

PET/CT allows stratification of responders to neoadjuvant chemotherapy for high-grade sarcoma: a prospective study

PURPOSE

The aim of the present study was to determine whether metabolic reduction is capable of reflecting the histopathologic response and outcome after neoadjuvant chemotherapy in patients with high-grade sarcoma.

PATIENTS AND METHODS

Forty-two patients with histologically proven high-grade sarcoma underwent neoadjuvant chemotherapy followed by surgical resection. Quantitative F-18 fluorodeoxyglucose (F-18-FDG) positron emission tomography (PET)/computed tomography scans were acquired before and after the first cycle and after completion of neoadjuvant chemotherapy. Standardized uptake values (SUVs) and metabolic reduction rates were compared with histopathologic response, progression-free survival, and overall survival.

RESULTS

Baseline SUVmax was 10.9 ± 3.6 (range, 3.8-19.6). Therapeutic effect resulted in 10 patients (24%) with a satisfactory response and in 32 patients (76%) with an unsatisfactory response after completion of neoadjuvant chemotherapy. The SUV decreased to 7.8 ± 3.4 after the first cycle (t1) of chemotherapy and to 5.2 ± 3.4 after completion (t2) of chemotherapy. Histopathologic response and percentage SUV (t2) reduction rate were independent predictors of progression-free survival and overall survival in the multivariate analyses.

CONCLUSION

Metabolic reduction after neoadjuvant chemotherapy evaluated by F-18 FDG PET or computed tomography can be used for stratification of the histopathologic response in patients with high-grade sarcoma.

Primary (de novo) dedifferentiated liposarcoma in the extremities: a multi-institution Tohoku Musculoskeletal Tumor Society study of 18 cases in northern Japan

OBJECTIVE

Dedifferentiated liposarcomas usually occur in the retroperitoneal space and relatively rarely in the extremities.

METHODS

We identified 18 patients with primary dedifferentiated liposarcoma in the extremities from the files of Tohoku Musculoskeletal Tumor Society and analyzed demographics, histologic findings, treatments and prognostic factors. The average follow-up period was 58 months.

RESULTS

The subjects were 12 men and 6 women with a mean age of 65 years. All tumors were in the thigh. Nine patients noticed a rapid enlargement of the long-standing tumor. Histologic subtypes of the dedifferentiated area were undifferentiated pleomorphic sarcoma (n = 12), osteosarcoma (n = 2), rhabdomyosarcoma (n = 2), leiomyosarcoma (n = 1) and malignant peripheral nerve sheath tumor (n = 1). In the patient with rhabdomyosarcoma-like dedifferentiated area, extensive necrosis was observed after the preoperative chemotherapy. One patient who underwent marginal excision developed a local recurrence, but inadequate surgical margin was not associated with a risk of local recurrence. Three patients had lung metastasis at initial presentation, and four other patients developed lung metastases during the follow-up period. The overall survival rate was 61.1% at 5 years. On univariate analyses, large size of the dedifferentiated area (>8 cm), high MIB-1-labeling index (>30%) for the dedifferentiated area and lung metastasis at initial presentation were significantly associated with poor prognosis.

CONCLUSIONS

Primary dedifferentiated liposarcoma in the extremities predominantly occurred in the thigh and a rapid enlargement of long-standing tumors was a characteristic symptom. Although the local behavior of these tumors was less aggressive than that of retroperitoneal dedifferentiated liposarcomas, they had a relatively high metastatic potential.

Soft tissue sarcoma with metastasis to the stomach: A case report

Soft tissue sarcomas are unusual malignancies comprising 1% of cancer diagnoses in the United States. Undifferentiated pleomorphic sarcoma accounts for approximately 5% of sarcomas occurring in adults. The most common site of metastasis is the lung, with other sites being bone, the brain, and the liver. Metastasis to the gastrointestinal tract has rarely been documented. We present an unusual case of high-grade pleomorphic sarcoma with metastasis to the stomach, complicated by upper gastrointestinal bleeding.

Prognostic significance of Minichromosome maintenance protein 7 and Geminin expression in patients with 109 soft tissue sarcomas

Minichromosome maintenance complex (MCM2-7) and Geminin are important in the prevention of DNA re-replication in the cell cycle, and are also prognostic markers for numerous human malignancies. The present study examined Minichromosome maintenance protein 7 (MCM7) and Geminin expression in human soft tissue sarcomas (STSs) to clarify their correlation to the clinicopathological factors. Immunohistochemistry was performed to detect the expression of MCM7, Geminin and Ki-67 on paraffin-embedded sections of 109 STSs. Labeling indices (LIs) of the molecules were evaluated in the tumors. Higher LIs of MCM7, Geminin and Ki-67 were significantly correlated with distant metastasis (P<0.01), histological grade (P<0.01) and poor prognosis (P<0.01), respectively. LIs of MCM7 and Geminin were significantly correlated with Ki-67 LIs, (MCM7/Ki-67: rs=0.745, P<0.01 and Geminin/Ki-67: rs=0.604, P<0.01). Multivariate analyses showed that the higher LIs of Geminin, but not MCM7 and Ki-67, were shown to be an independent factor of poorer prognosis (relative risk 2.72, P=0.013). The immunohistochemical expression of MCM7 and Geminin may be novel and useful markers for evaluating the prognosis in patients with human STS.

Immunohistochemical expression of vascular endothelial growth factor and vascular endothelial growth factor receptor in canine cutaneous fibrosarcomas

The expression of five markers associated with tumour angiogenesis, proliferation and apoptosis was studied in 24 canine cutaneous fibrosarcomas. Tumours were assigned histological grades and were immunohistochemically evaluated for the expression of vascular endothelial growth factor (VEGF) and vascular endothelial growth factor receptor-2 (VEGFR-2). Additionally, intra-tumour microvessel density (iMVD) was assessed by immunohistochemical labelling for expression of von Willebrand factor (vWf) and tumour proliferation index (PI) was measured following labelling of Ki-67 antigen. Finally, tumour apoptotic index (AI) was determined by application of the terminal deoxynucleotidyl transferase (TdT)-mediated dUTP end-labelling method (TUNEL). VEGF and VEGFR-2 expression were detected in 22/24 (92%) and 24/24 (100%) of fibrosarcomas, respectively. There was correlation between VEGF and VEGFR-2 expression (r = 0.51) and between histological grade and PI (r = 0.82). A significant difference in PI between tumours of different histological grade was found (P < 0.05). The median PI in grade 2 and 3 tumours (30.6 and 54.7, respectively) was significantly higher than in grade 1 tumours (6.4). Therefore, only PI correlates significantly with the histological grade of canine cutaneous fibrosarcomas. The potential for autocrine activity for VEGF exists in canine cutaneous fibrosarcomas, as VEGF and VEGFR-2 expression was found in most tumours.

Proliferation and apoptosis of tumour cells before and after neoadjuvant therapy for high-grade extremity sarcomas: divergent associations with tumour response and prognosis

AIMS

To evaluate proliferation and apoptosis in high-grade sarcomas of the extremities before and after preoperative radio-hyperthermo-chemotherapy (RHC) and to determine the relationship between these parameters and treatment outcomes.

METHODS AND RESULTS

Pre- and post-RHC specimens of 41 soft tissue and bone tumours were immunohistochemically stained for minichromosome maintenance protein (MCM) 2 and caspase 3 as proliferation and apoptosis markers, respectively, based on a preliminary study comparing them with conventional markers. Indices were calculated as a percentage of positive cells by counting tumour cells in the most frequently labelled areas. MCM2, caspase 3 and MCM2/caspase 3 (growth) indices were 45.3 +/- 21.9%, 4.1 +/- 7.1% and 82.9 +/- 104.5, respectively, in pre-RHC specimens and 35.4 +/- 30.8%, 39.2 +/- 34.6% and 5.3 +/- 11.7, respectively, in post-RHC specimens. Response scores showed positive correlation with pre-RHC MCM2 and post-RHC caspase 3 indices, inverse correlation with post-RHC MCM2 and post-RHC growth indices and no correlation with prognosis. Multivariate analysis revealed high pre-RHC MCM2 and high post-RHC growth indices as significant unfavourable prognostic factors.

CONCLUSIONS

High proliferative activity in untreated sarcoma may predict good response to neoadjuvant therapy, but poor prognosis, whereas a high growth index, i.e. high proliferation:apoptosis ratio in a post-neoadjuvant therapy tumour specimen may indicate poor response and poor prognosis.

Standardizing evaluation of sarcoma proliferation- higher Ki-67 expression in the tumor periphery than the center

Soft tissue sarcomas often present as large and histopathologically heterogenous tumors. Proliferation has repeatedly been identified as a prognostic factor and immunostaining for Ki-67 represents the most commonly used proliferation marker. There is, however, a lack of consensus on how to evaluate Ki-67 staining regarding optimal cut-off levels, selection of tumor areas, and the number of tumor cells to evaluate. We assessed the impact of targeting peripheral versus central tumor areas using tissue microarray-based staining for Ki-67 throughout the tumor diameter in 25 leiomyosarcomas. In 18/25 tumors, Ki-67 expression was higher in the tumor periphery. If 10% staining tumor nuclei was used as cut-off and the maximal Ki-67 staining section in the tumor periphery was considered, 21/25 tumors would have been classified as highly proliferative compared to 14/25 if the tumor center had been analyzed. Similar results were obtained also when higher cut-off levels were used and if the mean expression rather than the maximal expression was considered and the differences were neither caused by necrosis nor by hypoxia (assessed as HIF-1alpha expression). Our findings suggest that the determination of proliferation in soft tissue sarcomas should be standardized for clinical application of Ki-67 as a prognostic marker.

Primary pulmonary and mediastinal synovial sarcoma: a clinicopathologic study of 60 cases and comparison with five prior series

Primary pulmonary and mediastinal synovial sarcoma is rare and poses a diagnostic challenge particularly when unusual histological features are present. We present 60 cases of primary pulmonary and mediastinal synovial sarcoma (29 male and 27 female subjects; mean age, 42 years) and compare our results with five prior series to better define unusual histological features. Clinically, patients with mediastinal synovial sarcoma were younger with a male gender bias. Radiologically, tumors were well delineated with distinctive magnetic resonance imaging features and little vascular enhancement. In all, 21/46 patients died of disease within 5 years. Histologically, all tumors had dense cellularity, interlacing fascicles, hyalinized stroma, and mast cell influx. Hemangiopericytoma-like vasculature (48/60), focal myxoid change (30/60), and entrapped pneumocytes (23/60) were seen. Calcification was not prevalent (10/60). Unusual histological features included Verocay body-like formations (7/60), vague rosettes (6/60), well-formed papillary structures (3/60), adenomatoid change (3/60), and rhabdoid morphology (2/60). Immunohistochemistry demonstrated expression of pancytokeratin (39/58), epithelial membrane antigen (29/53), cytokeratin 7 (26/40), cytokeratin 5/6 (5/7), calretinin (15/23), CD99 (19/23), bcl-2 (24/24), CD56 (11/11), S-100 (9/51), and smooth muscle actin (8/32). In total, 92% (36/39) of primary pulmonary and mediastinal synovial sarcomas studied were positive for t(x;18). In conclusion, our study confirms the clinical, histological, immunohistochemical, and molecular data from previous large series of primary pulmonary and mediastinal synovial sarcoma. Compared with soft tissue synovial sarcoma, primary pulmonary and mediastinal synovial sarcoma has less calcification, less obvious mast cell influx, and less radiologic vascularity, but similar magnetic resonance imaging features, percentage of poorly differentiated tumors, and number of t(x;18)-positive tumors. Awareness of focal unusual histology can prevent misdiagnosis particularly in t(x;18)-negative tumors.

Histological grading and MIB-1 labeling index of soft-tissue sarcomas

Soft-tissue sarcomas or malignant soft-tissue tumors are malignant tumors arising from soft tissues of mesenchymal origin. These soft-tissue tumors can develop from any site in the body, including the extremities, trunk, retroperitoneum, or the head/neck region. In Japan, soft-tissue sarcomas are rarely encountered, with an incidence of approximately 2 per 100 000 population. Diverse types (more than 30 types) of soft-tissue sarcomas are known. Pathological examination of biopsy or resected specimens is indispensable for a definitive diagnosis of soft-tissue sarcomas. Needless to say, early detection and treatment based on accurate diagnosis are the basic principles of the management of soft-tissue sarcomas. The purpose of the present paper was to address the histological grading of soft-tissue sarcomas (the most important histopathological prognostic factor for this type of sarcoma) based on the French Fédération Nationale des Centres de Lutte Contre Ie Cancer (FNCLCC) system, the histological grading of this type of sarcoma based on the MIB-1 labeling index (an immunohistochemical marker of cell proliferation; MIB-1 system), precautions that must be taken while evaluating the degree of malignancy and the relationship of the grade with other clinicopathological factors.

Intratumoral heterogeneity of MIB-1 labelling index in gastric gastrointestinal stromal tumor (GIST)

BACKGROUND

The MIB-1 labelling index (LI) is used as a prognostic indicator for gastrointestinal stromal tumors (GISTs). However, whether a biopsy-based LI represents the entire tumor is uncertain, because the LI is not always homogeneous. In this study, we examined the extent and characteristics of LI heterogeneity in gastric GISTs.

METHODS

We analyzed ten c-kit-positive gastric GISTs with diameters exceeding 3 cm, of which six were multilobular and four were unilobular. For MIB-1-immunostained sections, continuous digital images were obtained through the maximum diameter of the lobules. We obtained LIs for images by carrying out computer-assisted image analysis, and calculated the means and standard deviations (SDs) of the LIs for the lobules. For each lobule, intralobular heterogeneity was evaluated on the basis of the SD. For multilobular tumors, interlobular heterogeneity was assessed on the basis of the mean LI difference between lobules.

RESULTS

The SDs, which ranged from 0.8% to 9.8%, indicated intralobular heterogeneity. Moreover, considerable interlobular heterogeneity was noted in five (83%) of the six multilobular GISTs, in which the maximum interlobular mean LI difference ranged from 9.6% to 27.2%. Notably, although the high maximum mean LI (14.1%-32.3%) showed that these five GISTs were high-grade tumors, they also contained at least one lobule showing a low-grade mean LI value (2.7%-5.1%).

CONCLUSION

Gastric GISTs often show intralobular or interlobular MIB-1 LI heterogeneity. In multilobular GISTs, multiple biopsy samples may be required for the accurate evaluation of tumor grade.