Recent advances in the diagnosis of soft tissue tumours

Lipomatous Neoplasms of Soft Tissue: A Contemporary Review

This review summarizes the clinicopathologic features of various lipomatous tumors of soft tissue and addresses some recent conceptual issues relating to adipocytic neoplasms, such as atypical spindle cell/pleomorphic lipomatous tumor and myxoid pleomorphic liposarcoma, and provides an update on the molecular aspects of these tumors. Recent advances in cytogenetic characterization and classification of lipomatous tumors are reviewed, and the genetic importance of distinct chromosomal aberrations are briefly discussed.

Rare primary intrapulmonary malignant peripheral nerve sheath tumor showing significant response to sintilimab: A case report and literature review

Primary pulmonary malignant peripheral nerve sheath tumor (MPNST) is a rare soft tissue sarcoma with a low incidence, poor prognosis and limited treatment options. The present study reported a case of lung MPNST in a 63-year-old male patient without any pulmonary symptoms. Immunohistochemical analysis of the tumor indicated a programmed death-ligand 1 (PD-L1) expression tumor proportion score of 60%. A total of six courses of sintilimab were used in this patient and a remarkable response was achieved. In summary, sintilimab single-agent immunotherapy may be a novel treatment for pulmonary MPNST. When encountering analogous cases in the future, oncologists can test for the expression of PD-L1 in patients to guide the therapy's design.

Accuracy of core needle biopsy for histologic diagnosis of soft tissue sarcoma

The biopsy technique of choice in soft tissue sarcoma (STS) diagnosis is controversial. We examined the diagnostic accuracy of percutaneous core needle biopsy (CNB) and compared it to open incisional biopsy. A retrospective study included 91 incisional biopsies and 102 CNBs. A pair-match investigation was conducted on 19 patient pairs, comparing sensitivity, specificity, and diagnostic accuracy. Furthermore, we investigated the role of molecular pathology in sarcoma diagnostics. In 81/91 (89%) patients with incisional biopsy, the entity was confirmed by definitive pathology, whereas this was the case in 89/102 (87%) CNB patients (p = 0.52). Grading remained unchanged in 46/55 (84%) of incisional and 54/62 (87%) of CNBs (p = 0.61). The pair matched analysis showed that the correct entity was determined in 96% of incisional and 97.6% of core needle biopsies. The time between the initial consultation and the interdisciplinary tumor board's treatment recommendation was shorter in core needle biopsies (8.37 vs. 15.63 days; p < 0.002). Incisional biopsies led to two wound infections and one hematoma, whereas wound infection occurred in one patient after CNB. CNB leads to faster diagnosis while reaching the same histological accuracy and is less burdensome for patients. Still, surgeons need to remain aware of the possibility of biopsy failure.

Mesenchymal Tumors of the Mediastinum: An Update on Diagnostic Approach

Mesenchymal tumors of the mediastinum are a heterogenous group of rare tumors with divergent lineages. Mediastinal mesenchymal tumors are diagnostically challenging due to their diversity and morphologic overlap with nonmesenchymal lesions arising in the mediastinum. Accurate histologic diagnosis is critical for appropriate patient management and prognostication. Many mediastinal mesenchymal tumors affect distinct age groups or occur at specific mediastinal compartments. Neurogenic tumors, liposarcoma, solitary fibrous tumor, and synovial sarcoma are common mesenchymal tumors in the mediastinum. Herein, we provide an update on the diagnostic approach to mediastinal mesenchymal tumors and a review of the histologic features and differential diagnosis of common benign and malignant mesenchymal tumors of the mediastinum.

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.

Immunohistochemical evaluation of suspected oral malignant melanoma in cats

Oral malignant melanoma (OMM) is considered the third most common oral malignant neoplasm in cats, but its variable morphology and frequent lack of melanin pigment make it a diagnostic challenge. Twenty-two cases of cats with malignant oral neoplasms that were diagnosed as OMM or listed OMM as a suspected differential diagnosis on the biopsy report were examined using an immunohistochemistry (IHC) panel for S100, melan-A, PNL2, laminin, CD34, and pan-cytokeratin. Although OMM was suspected (n = 14) or previously diagnosed (n = 8), only 2 cases were immunohistochemically confirmed as OMM. Seven cases were classified as soft tissue sarcoma based on positive expression of CD34 or laminin, and one was classified as carcinoma based on positive expression of pan-cytokeratin. The majority of cases (n = 12) were categorized as unclassified malignant neoplasms because they did not express melan-A, PNL2, laminin, CD34, or pan-cytokeratin; however, a proportion of these did express S100 (n = 7). Long-term prognosis of all 22 cats was poor, with a median survival time of 87 days (range = 2-249 days). Cases with longer survival times (>100 days) were treated with surgery, radiation therapy, or a combination. For feline oral malignant neoplasms thought to be OMM, routine use of IHC is required for an accurate diagnosis.

Soft Tissue Perivascular Epithelioid Cell Tumour: An Unusual Finding

Perivascular epithelioid cell tumour (PEComa) is a rare mesenchymal tumour made up of clear perivascular cells with epithelioid characteristics, which co-expresses muscle and melanocytic markers with a component of spindle cells, like sarcoma and variety of other tissues. This time, we present the case of a young patient with a tumour in the dorsal region of progressive growth, compatible with PEComa of soft tissue after histopathological and immunohistochemical analysis.

Are preoperative complete blood count parameters in peripheral nerve sheath tumors useful diagnostic tools?

OBJECTIVES

This study aims to evaluate the diagnostic value of complete blood count (CBC) parameters in patients with peripheral nerve sheath tumors (PNSTs).

PATIENTS AND METHODS

A total of 181 patients (83 males, 98 females; median age: 44 years; range, 15 to 83 years) who underwent surgical treatment for PNSTs in our tertiary oncology center between January 2010 and December 2019 were retrospectively analyzed. Eighty-two patients were diagnosed with a neurofibroma, 79 with a schwannoma, and 20 with a malignant PNST (MPNST). The patient group was evaluated as malignant (n=20) and benign (n=161). Age- and sex-matched patients admitted to our outpatient clinic of orthopedic and traumatology with non-specific symptoms other than tumor, infection, fracture, and rheumatological or hematological diseases were included as the control group (n=165). Data including age, sex, definitive histopathological diagnosis, and pre-treatment CBC values were obtained from the hospital records. Pre-treatment CBC values such as neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), and lymphocyte-to-monocyte ratio (LMR) were calculated for both malignant and benign groups and control groups. Diagnostic values of NLR, PLR, and LMR between PNST groups were assessed using the receiver operating characteristic (ROC) curve analysis.

RESULTS

Neurofibroma, schwannoma, and MNPST groups had significantly higher median NLR, compared to the control group (p<0.001), while the median LMR was significantly lower in these groups (p<0.05). However, the median PLR was higher only in the MPNST group, compared to the control group (p<0.001). Post-hoc analyses revealed that median NLR, PLR, and LMR ratios were similar in PNST groups, compared to the control group. In addition, the median NLR, PLR, and LMR ratios were similar between malignant and benign patient groups. The highest area under the curve (AUC) was found for NLR (AUC=0.756) and LMR (AUC=0.716) in the MPNST group.

CONCLUSION

Our study results suggest that NLR, PLR, and LMR may have an added value in the early diagnosis of PNSTs and are valuable for differentiating patients from healthy individuals, although their value in differential diagnosis is still unclear.

Severe Postoperative Complications are Associated with Impaired Survival in Primary but not in Recurrent Retroperitoneal Sarcoma

BACKGROUND

Retroperitoneal sarcoma (RPS) surgery entails multivisceral resection, which may cause postoperative complications. We assessed the effects of complications on survival to identify their predisposing factors in primary (PRPS) and recurrent (RRPS) RPS.

METHODS

We retrospectively analyzed our institutional database. Severe postoperative complications (SC) were defined as Clavien-Dindo classification ≥ 3. Predisposing factors for complications were investigated, as was their effect on long-term outcomes.

RESULTS

In total, 154 RPS resections (78 PRPS and 76 RRPS) performed between January 2008 and December 2018 were included. Neoadjuvant chemotherapy and multifocal tumors were more common in RRPS than PRPS (34.2% vs. 11.3%, P = 0.001 and 42.1% vs. 10.3%, P < 0.001, respectively). Although surgical extent in RRPS was limited compared with PRPS (weighted organ score 1 vs. 2, P = 0.01; transfusion requirement 23.6% vs. 35.8%, P = 0.04), SC and mortality rates were comparable. SC rates were 30.1% and 35.5% for PRPS and RRPS, respectively. NACT rate tended to be higher in PRPS patients with SC (20.8% vs. 7.4%, P = 0.09), whereas weighted organ score and transfusion requirement were increased in RRPS patients with SC (2 vs. 1, P = 0.01; 40.7% vs. 14.3%, P = 0.009, respectively). PRPS patients with SC had decreased overall survival (35 months, 95% confidence interval [CI] 12.2-57.7) compared with those without SC (90 months, 95% CI 71.4-108.5, P = 0.01).

CONCLUSIONS

Postoperative complications are associated with impaired outcomes in PRPS but not in RRPS. The negative effects of complications on outcomes should be factored to perioperative management.

Retroperitoneal Sarcomas: An Update on the Diagnostic Pathology Approach

Retroperitoneal sarcomas are a heterogenous group of rare tumors arising in the retroperitoneum. Retroperitoneal sarcomas comprise approximately 10% of all soft tissue sarcomas. Though any soft tissue sarcoma histologic types may arise in the retroperitoneal space, liposarcoma (especially well-differentiated and dedifferentiated types) and leiomyosarcoma do so most commonly. Retroperitoneal sarcomas are diagnostically challenging, owing to their diversity and morphological overlap with other tumors arising in the retroperitoneum. An accurate diagnosis is necessary for correct management and prognostication. Herein, we provide an update on the diagnostic approach to retroperitoneal sarcomas and review their key histologic findings and differential diagnoses.

Innate inflammatory markers for predicting survival in retroperitoneal sarcoma

INTRODUCTION

Existing prognostic tools for retroperitoneal sarcomas (RPS) utilize parameters that can be accurately determined only postoperatively. This study evaluated the application of the neutrophil-to-lymphocyte ratio (NLR) and C-reactive protein (CRP) levels for predicting prognosis in primary RPS.

MATERIALS AND METHODS

We retrospectively analyzed our database of patients with primary RPS operated between 2008 and 2018. The NLR was calculated from preoperative blood tests and its association with outcomes was determined.

RESULTS

The NLR values of 78 suitable patients were analyzed. Patients were classified in the NLR-high group if the NLR was ≥2.1. High-grade tumors were more common in the NLR-high group (71.6% vs 48%, P = .02). NLR-high patients had impaired overall survival (OS) and progression-free survival (PFS) compared to NLR-low patients (median OS not reached vs 74 months 95% confidence interval [CI]: 21.6-126.4, P = .03; median PFS not reached vs 48 months 95% CI: 6.5-98.6, P = .06, respectively). Multivariate analysis showed statistical significance only for PFS but not for OS (hazard ratio [HR] = 4.1, P = .03; HR = 2.3, P = .3). Patients with low CRP levels had improved OS and PFS.

CONCLUSIONS

The NLR may serve as a preoperative, easily derived marker for prognosis in RPS. Serum biomarkers may prove useful in these large and spatially heterogeneous tumors.

Cutaneous intravascular epithelioid hemangioma. A clinicopathological and molecular study of 21 cases

Pure intravascular growth of epithelioid hemangioma (EH) is exceptional. Herein, we report a series of 21 intravascular EHs, representing a potential serious diagnostic pitfall by mimicking malignant vascular neoplsms with epithelioid morphology. The tumors developed in 12 males and 4 females, aged from 11 to 71 years (mean age 40.2 years) with a predilection for the extremities (13 of 21, 61.9%), followed by the head and neck (8 of 21, 38.1%). Lesions ranged in size from 2 to 30 mm (mean size 13 mm). The most common presenting feature was a slowly growing nodule. Most neoplasms were solitary (13 of 16 patients, 81.2%) but three patients developed more than one intravascular EH (3 of 16, 18.8%). Treatment consisted of complete surgical excision and was generally curative. Follow-up was available for 13 lesions that had developed in ten patients (range 4-72 months, mean 27.3 months). No recurrences or development of additional tumors were observed. All 21 lesions developed in subcutaneous veins. Two morphological patterns of intravascular epithelioid endothelial cell proliferation were observed: (1) a lobular capillary hemangioma-like proliferation with variable formation of open vascular lumina and (2) a solid proliferation generally lacking open vascular spaces. A lobular capillary hemangioma-like pattern was the sole pattern in nine lesions, a mixed lobular hemangioma-like pattern, and solid pattern in eight and a pure solid pattern in four intravascular EHs. Mitotic activity in epithelioid endothelial cells ranged from 0 to 7 mitoses per 10 high-power field (mean 2.1 mitoses per 10 HPFs). Six lesions displayed brisk mitotic activity of five or more mitoses per 10 HPF (6 of 21, 28.5%). The number of mitoses was usually more prominent in areas with solid growth. Atypical mitoses were not observed. No intratumoral necroses were seen. Cytological atypia was mild (20 out of 21 cases). By immunohistochemistry, all tumors were positive for CD31 (14 out of 14) and ERG (5 out of 5). While all tested cases were FOS negative by immunohistochemistry (6 out of 6), one out of six cases (case 6) displayed FOSB nuclear positivity in about 30% of the lesional endothelial cells. Eight cases were analysed by FISH for the presence of FOS and FOSB gene rearrangements. While all cases were negative for FOSB rearrangements, a single case proved positive for FOS gene break-apart. In conclusion, intravascular growth of EH is not associated with adverse biological behavior. Solid intravascular proliferations of endothelial cells can mimic a malignant vascular tumor with epithelioid morphology. Nevertheless, intravascular EHs display mild cytological atypia coupled with low mitotic activity, and a lack of atypical mitoses, pronounced nuclear atypia, multilayering or tumor necrosis. Finally, the FOS gene is infrequently rearranged, and there are no FOSB gene abnormalities in this subset of EHs, suggesting a potential distinct pathogenesis than most classic EHs.

Epithelioid Cutaneous Mesenchymal Neoplasms: A Practical Diagnostic Approach

Epithelioid cells are rounded or polygonal cells with abundant eosinophilic or clear cytoplasm and ovoid to round nuclei, superficially resembling epithelial cells. Cutaneous mesenchymal neoplasms composed predominantly or exclusively of epithelioid cells are relatively uncommon and can cause considerable diagnostic difficulties due to overlapping histologic features among heterogeneous groups of tumors. Familiarity with practical diagnostic approaches and recognition of key histopathologic features are important for correct diagnosis and management. This review summarizes the histologic features of epithelioid cutaneous mesenchymal neoplasms and discusses their differential diagnoses from malignant melanomas and carcinomas.

Pharmacogenomics Biomarkers of Soft Tissue Sarcoma Therapies

Soft tissue sarcomas (STS) are heterogeneous rare malignancies comprising ~1% of all solid cancers in adults and including more than 70 histological and molecular subtypes with different pathological and clinical development characteristics. Over the last two decades, the increased knowledge of the new molecular and genomic mechanisms of different STS histotypes allowed for a reclassification of these tumors and consequently to the development of novel chemotherapeutic agents. Generally, surgery, in combination with radiotherapy only in selected cases of localized disease, represents the most common treatment of primary STS, whereas the principal treatment modality for locally advanced or metastatic disease is first-line chemotherapy. The principal treatment for the preponderance of STS patients is usually an anthracycline (epirubicin and doxorubicin) in monotherapy or in combination with other drug novel chemotherapeutic agents. However, survival for treated patients with metastatic disease is poor, and a 2-years survival rate is about 30%. In this scenario, Pharmacogenomics (PGx) biomarkers that can predict drug response play an important role in the improvement of molecular diagnostics in clinical routines and contribute to elucidating the genetic basis for the differences in treatment efficacy and toxicity among STS patients. This review focuses on recent insight in the PGx biomarkers that have been described to modulate responsiveness and toxicity parameters of conventional and new chemotherapeutics drugs in several STS histotypes.

Fine-Needle Aspiration Features of BCOR-CCNB3 Sarcoma

OBJECTIVES

BCOR-CCNB3 sarcoma (BCS) is an undifferentiated tumor that has some clinical and morphologic similarity to classic Ewing sarcoma, but it is characterized by a distinct BCOR-CCNB3 gene fusion. There are no reports describing its cytomorphologic findings.

METHODS

We describe cytologic findings of five molecularly proven BCS cases (four males and one female, aged 8.5-22 years).

RESULTS

Smears showed mainly round cells, but some spindle cells and rhabdoid-like cells were also observed. Dispersed cells dominated in smears, but also distinct pseudopapillary structures with vascular cores were noted in four cases. Scant connective tissue fragments were found in four cases. There was no rosette formation in any case.

CONCLUSIONS

BCS should be differentiated from other round cell tumors. Some cytologic features, especially rhabdoid-like cells, connective tissue fragments, and pseudopapillary formations, combined with immunohistochemical and molecular studies, may be helpful in making the appropriate diagnosis.

Hippo pathway effectors YAP1/TAZ induce an EWS-FLI1-opposing gene signature and associate with disease progression in Ewing sarcoma

YAP1 and TAZ (WWTR1) oncoproteins are the final transducers of the Hippo tumor suppressor pathway. Deregulation of the pathway leads to YAP1/TAZ activation fostering tumorigenesis in multiple malignant tumor types, including sarcoma. However, oncogenic mutations within the core components of the Hippo pathway are uncommon. Ewing sarcoma (EwS), a pediatric cancer with low mutation rate, is characterized by a canonical fusion involving the gene EWSR1 and FLI1 as the most common partner. The fusion protein is a potent driver of oncogenesis, but secondary alterations are scarce, and little is known about other biological factors that determine the risk of relapse or progression. We have observed YAP1/TAZ expression and transcriptional activity in EwS cell lines. Analyses of 55 primary human EwS samples revealed that high YAP1/TAZ expression was associated with progression of the disease and predicted poorer outcome. We did not observe recurrent SNV or copy number gains/losses in Hippo pathway-related loci. However, differential CpG methylation of the RASSF1 locus (a regulator of the Hippo pathway) was observed in EwS cell lines compared with mesenchymal stem cells, the putative cell of origin of EwS. Hypermethylation of RASSF1 correlated with the transcriptional silencing of the tumor suppressor isoform RASFF1A, and transcriptional activation of the pro-tumorigenic isoform RASSF1C, which promotes YAP1/TAZ activation. Knockdown of YAP1/TAZ decreased proliferation and invasion abilities of EwS cells and revealed that YAP1/TAZ transcription activity is inversely correlated with the EWS-FLI1 transcriptional signature. This transcriptional antagonism could be explained partly by EWS-FLI1-mediated transcriptional repression of TAZ. Thus, YAP1/TAZ may override the transcriptional program induced by the fusion protein, contributing to the phenotypic plasticity determined by dynamic fluctuation of the fusion protein, a recently proposed model for disease dissemination in EwS. © 2019 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of Pathological Society of Great Britain and Ireland.

[Resection of soft tissue tumours : Pitfalls, typical complications and prevention strategies]

Benign soft tissue lesions are 300 times as common as soft tissue sarcomas; hence, the likelihood of confusion is high. Lesions that are larger than 5 cm, deep, show infiltrative growth, or recur despite benign histology are suspicious for soft tissue sarcoma. The biopsy incision must be carefully chosen; in large lipomas, atypical lipomatous tumor should be considered in the differential diagnosis. Lymphomas can be misdiagnosed and treated as undifferentiated soft tissue sarcoma. Vascular tumors and epithelioid lesions require more attention in histopathologic diagnostics and staging. Inflammatory lesions and aggressive fibromatosis (desmoid tumor) should also be borne in mind. In general, staging should be adapted to the underlying tumor biology. Neoadjuvant and adjuvant multimodal therapy must be discussed with the patient and used in a targeted manner. Superficial infiltrating sarcomas are prone to intralesional resection and may require intraoperative frozen section histology. If plastic reconstruction is necessary, a two-step procedure after proven tumor-free margins can be beneficial. Cavities and seromas, tight sutures, and closing the wound with clips are particularly critical. Wound drains at the thigh, pelvis, and groin should be left longer. Early revision in cases of hematoma or critical wound healing have proven beneficial. Adjuvant therapies are best planned before discharge from hospital. Overall, tumor-specific follow-up can significantly reduce the disadvantages of a recurrence resection.

Signatures of circulating microRNA in four sarcoma subtypes

Background: Sarcomas are rare malignant tumors of mesenchymal origin. The discovery of circulating biomarkers with high diagnostic value could supplement diagnosis of this heterogenous group of tumors. The aim of this study was to identify the profiles of circulating miRNA (c-miRNAs) in four groups of common bone and soft tissue sarcomas.

Methods: At the time of diagnosis, blood samples were collected from 86 patients: 36 with locally advanced/unresectable/metastatic gastrointestinal stromal tumor (GIST) who received first-line treatment with imatinib; 16 with locally advanced osteosarcoma (OS); 26 with locally advanced synovial sarcoma (SS); and eight with locally advanced Ewing sarcoma (ES). In addition, samples were collected from 30 healthy controls. C-miRNAs were isolated using a miRCURY RNA Isolation Kit, followed by preparation of cDNA libraries and sequencing on the Ion Proton platform.

Results: Pair-wise comparisons identified 156 unique c-miRNAs (adjusted P-value < 0.05) showing significant dysregulation between controls and patients; of these, 24, 36, 42, and 99 differentiated controls from pretherapeutic OS, SS, ES, and GIST, respectively. Ten c-miRNAs were commonly altered in at least three sarcoma types. Receiver operating characteristic curves and area under the curve (ROC-AUC) analyses revealed that a four-miRNA diagnostic classifier was able to differentiate controls from ES, GIST, OS, and SS, with AUC-ROC values of 1, 0.97, 0.95, and 0.94, respectively.

Conclusions: Aberrant miRNA expression signatures were identified in serum from patients with four different sarcoma subtypes. Differences in miRNA expression profiles between sarcoma patients and healthy volunteers suggest that miRNAs may play a role in sarcoma development.

What's new in adipocytic neoplasia?

Adipocytic tumors are frequently encountered in routine practice, and while the vast majority represent commonly encountered tumor types (e.g., benign lipoma), the heterogeneity and rarity of other adipocytic neoplasms can pose diagnostic challenges. Atypical and malignant adipocytic tumors account for approximately 20% of all sarcomas. The 2013 World Health Organization (WHO) classification of soft tissue and bone tumors recognizes four major liposarcoma subtypes, characterized by distinct clinical behavior, distinctive morphologies, as well as unique genetic findings: atypical lipomatous tumor/well-differentiated liposarcoma, dedifferentiated liposarcoma, myxoid liposarcoma, and pleomorphic liposarcoma. Since the publication of the 2013 WHO classification of soft tissue and bone tumors, the most notable change in the category of adipocytic tumors has been made in the clinicopathologic and molecular characterization of the heterogeneous but distinct group of "atypical low-grade adipocytic neoplasms with spindle cell features," for which the term atypical spindle cell/pleomorphic lipomatous tumor has been proposed. Another substantive change in the group of adipocytic tumors is the introduction of pleomorphic myxoid liposarcoma (myxoid pleomorphic liposarcoma) as an apparently novel subtype of aggressive liposarcoma, especially occurring in children and young adults with a predilection for the mediastinum. This review will further focus upon the diagnostic criteria of these novel emerging entities in the group of adipocytic tumors.

Ion channels in sarcoma: pathophysiology and treatment options

Sarcomas are characterized by aggressive growth and a high metastasis potentially leading in most cases to a lethal outcome. These malignant tumors of the connective tissue have a high heterogeneity with numerous genetic mutations resulting in more than 100 types of sarcoma that can be grouped into two main kinds: soft tissue sarcoma and bone sarcoma. Sarcomas are often diagnosed at late disease stage, whereas a guaranteed diagnosis of the sarcoma type is fundamental for successful therapy. However, there is no appropriate therapy available. Therefore, the need for new therapies, which prolong survival and improve quality of life, is high. In the last two decades, the role of ion channels in cancer has emerged. Ion channels seem to be an ideal target for anti-tumor therapies. However, different cancer types have their own altered ion channel pattern, and the knowledge about the tumor-associated ion channel expression is fundamental. Here, we focus on the role of different ion channels in sarcoma, their pathophysiology, and possible treatment options.

Early Wound Site Seeding in a Patient with Central Nervous System High-Grade Neuroepithelial Tumor with BCOR Alteration

BACKGROUND

Advances in molecular profiling have facilitated the emergence of newly defined entities of central nervous system (CNS) tumor, including CNS high-grade neuroepithelial tumor with BCOR alteration (CNS HGNET-BCOR). Relatively little is known about the clinical behavior of these newly characterized tumors.

CASE DESCRIPTION

We describe a pediatric male patient with CNS HGNET-BCOR, who developed seeding of the tumor into the site of the surgical wound within months of surgery and who underwent resection of a residual posterior fossa tumor.

CONCLUSIONS

This case emphasizes 3 important points. First, CNS HGNET-BCOR can be aggressive tumors that necessitate close clinical and radiologic surveillance. Second, surveillance imaging in such cases should incorporate the surgical incision site into the field of view, and this should be closely scrutinized to ensure the timely detection of wound site seeding. Third, wound site seeding may still occur despite the use of meticulous surgical techniques.