Addressing Modern Diagnostic Pathology for Patient-Derived Soft Tissue Sarcosphere Models in the Era of Functional Precision Oncology.

Responses to therapy often cannot be exclusively predicted by molecular markers, thus evidencing a critical need to develop tools for better patient selection based on relations between tumor phenotype and genotype. Patient-derived cell models could help to better refine patient stratification procedures and lead to improved clinical management. So far, such ex vivo cell models have been used for addressing basic research questions and in preclinical studies. As they now enter the era of functional precision oncology, it is of utmost importance that they meet quality standards to fully represent the molecular and phenotypical architecture of patients' tumors. Well-characterized ex vivo models are imperative for rare cancer types with high patient heterogeneity and unknown driver mutations. Soft tissue sarcomas account for a very rare, heterogeneous group of malignancies that are challenging from a diagnostic standpoint and difficult to treat in a metastatic setting because of chemotherapy resistance and a lack of targeted treatment options. Functional drug screening in patient-derived cancer cell models is a more recent approach for discovering novel therapeutic candidate drugs. However, because of the rarity and heterogeneity of soft tissue sarcomas, the number of well-established and characterized sarcoma cell models is extremely limited. Within our hospital-based platform we establish high-fidelity patient-derived ex vivo cancer models from solid tumors for enabling functional precision oncology and addressing research questions to overcome this problem. We here present 5 novel, well-characterized, complex-karyotype ex vivo soft tissue sarcosphere models, which are effective tools to study molecular pathogenesis and identify the novel drug sensitivities of these genetically complex diseases. We addressed the quality standards that should be generally considered for the characterization of such ex vivo models. More broadly, we suggest a scalable platform to provide high-fidelity ex vivo models to the scientific community and enable functional precision oncology.

Spectrum of Histopathological, Immunohistochemical, Molecular and Radiological Features in 12 Cases of BCOR::CCNB3-positive Sarcomas With Literature Review.

Introduction BCOR::CCNB3-positive undifferentiated sarcomas are rare. Herein, we present clinicopathological features including immunohistochemical and molecular data, along with the radiological profile of 12 such tumors. Methods Tumors were tested for BCOR::CCNB3 fusion by reverse transcription polymerase chain reaction (RT-PCR) technique. Eight tumors were tested for EWSR1 and three for SS18 gene rearrangements by fluorescence in situ hybridization, and two for SS18::SSX fusion by fragment analysis. Results Ten of 12 patients were male with ages ranging between 4 and 17 years (median = 13, average = 14.4). Nine tumors occurred in bones and three in soft tissues (median size = 8 cm). Four of five tumors within the appendicular bones were metadiaphyseal and appeared as permeative lesions, invariably associated with cortical thickening. Three tumors displayed mineralization. Histopathologically, the tumors comprised round to epithelioid cells with round to oval to spindle-shaped nuclei, mostly diffusely arranged in a myxoid stroma with intervening thin-walled vessels. Immunohistochemically, tumor cells were positive for BCOR (10/11), SATB2 (8/9), TLE1 (5/6), cyclinD1 (4/4), and EMA (3/8). All tumors revealed BCOR::CCNB3 fusion transcript. Nine patients underwent neoadjuvant chemotherapy, including five who underwent surgical resection, with two patients, who received adjuvant radiation therapy. A single patient, each, underwent palliative chemotherapy and palliative radiotherapy, respectively. Four patients developed pulmonary metastasis and three developed local recurrences. Four patients were alive-with-disease and two were free-of-disease. Conclusions It is crucial to identify BCOR::CCNB3 fusion-positive sarcomas, given significant treatment-associated implications. Certain clinicoradiological, histopathological features, absent EWSR1 rearrangement and BCOR, SATB2, and TLE1 immunoexpression are useful for triaging these tumors for molecular testing. A review of the literature on these ultra-rare tumors, including their diagnostic mimics is presented.

Clinicopathological profile of myxoid soft tissue tumors- A retrospective study in a tertiary care hospital in South India.

Background: Myxoid soft tissue tumors are rare and diagnostically challenging group of tumors with varied biological behavior ranging from benign, locally aggressive to distantly metastasizing malignant tumors. Aims: The objectives of the study are to identify the relative frequency and distribution of myxoid soft tissue tumors among patients in a tertiary care hospital and to study the clinicopathological features of these tumors. This was a retrospective cross-sectional study conducted in the department of pathology of a tertiary care hospital from January 2008 to December 2013. Materials and Methods: Clinical and pathological details of all the 80 myxoid soft tissue tumors reported during the study period were retrieved from the records of department of pathology. Corresponding Hematoxylin & Eosin (H & E) slides were reviewed, and Immunohistochemistry (IHC) was carried out for confirmation. The relationship among various prognostic variables was analyzed in case of myxoid sarcomas. Results: Myxoid soft tissue tumors accounted for 3.7% among the soft tissue tumors with a predominance of malignant myxoid sarcomas (71.25%) in contrast to the overall picture of sarcomas. Myxoid neurofibroma (34.78%) was the most common benign tumor, while myxofibrosarcoma (33.33%) was the frequent myxoid sarcoma. A statistically significant correlation was seen between tumor size and depth (P-value: 0.038) and also between presence of vascular invasion and histological grade (P-value: 0.012) of sarcomas. Conclusion: Light microscopic morphology, supplemented by ancillary techniques like IHC, remains the cornerstone for diagnosis of myxoid soft tissue tumors.

Phosphaturic Mesenchymal Tumor of Soft Tissue of the Foot: Report of a Case With Review of the Literature.

Phosphaturic mesenchymal tumor (PMT) is a rare neoplasm that ectopically secretes fibroblast growth factor 23, a bone cell-derived protein that regulates phosphate homeostasis. The overproduction of fibroblast growth factor 23 causes a paraneoplastic syndrome characterized by hyperphosphaturia, hypophosphatemia, hypovitaminosis D, and vitamin D refractory rickets/osteomalacia, effects that disappear with tumor removal. The PMT may occur in several anatomic regions, mainly in the limbs, usually involving both soft tissue and bone. Acral locations occur in 10% to 15% of the cases, mostly in the feet, with 95 cases reported in this anatomic region to date. We report a case of a PMT in a young adult male who presented in 2007 with the classic constellation of signs and symptoms. A small soft-tissue tumor was detected in his right heel, 3 years after exhaustively seeking for it by various imaging techniques performed at different institutions. Before the tumor was detected, attempts to manage this patient's osteomalacia with phosphate and vitamin D (both calcitriol and ergocalciferol) supplementation were unsuccessful. Following surgical resection, the patient experienced prompt correction of the phosphaturia and gradual reconstitution of his bone mineralization. The pathologic diagnosis was (benign) PMT, mixed connective tissue type. In 2019, 12 years after resection, the patient is asymptomatic, and his bone mineral homeostasis has been restored.

Alveolar soft-part sarcoma: can MRI help discriminating from other soft-tissue tumors? A study of the French sarcoma group.

OBJECTIVES: To investigate the imaging features of alveolar soft-part sarcomas (ASPS) on pre-treatment MRI in order to identify relevant criteria to distinguish ASPS from other soft-tissue tumors. METHODS: A series of 25 patients (mean age, 18.5 years old) with histologically proven ASPS from five French comprehensive cancer centers was compared to a control cohort of 292 patients with various histologically proven benign and malignant soft-tissue tumors representative of the 10-year long activity of one center. All had a baseline MRI with contrast-agent administration. Two radiologists independently reviewed the MRIs. Features assessing location, size, signal, architecture, periphery, and vascularization were reported. Their association with the histological diagnosis of ASPS was evaluated with chi-square or Fisher's test. Their prevalence, sensitivity, specificity, odds ratio, and reproducibility were calculated. RESULTS: Eight MRI features were significantly associated with ASPS: deep location (p < 0.001), high signal intensities on T1-weighted imaging (p < 0.001), central area of necrosis (p = 0.001), absence of fibrotic component (p = 0.003), infiltrative growth pattern (p = 0.003), absence of tail sign (p = 0.001), presence of intra- and peritumoral flow-voids (p < 0.001), and number of flow-voids ≥ 5 (p < 0.001). Twenty out of the 25 (80%) ASPS showed at least 7 of these 8 features compared to only four out of 292 (1.4%) tumors of the control cohort (1 benign vascular tumor, 1 solitary fibrous tumor, 2 high-grade soft-tissue sarcomas). The five ASPS with less than 7 out of 8 features measured less than 40 mm. CONCLUSION: The striking histological uniformity of ASPS translates into imaging. However, ASPS may be misdiagnosed as benign tumors or pseudo-tumors, notably intramuscular benign vascular tumors or vascular malformations. KEY POINTS: • ASPS are rare aggressive mesenchymal tumors displaying recurrent MRI features highly reminiscent of the diagnosis. • Deep-seated tumors presenting with mainly high signal intensity on T1-weighted imaging, an absence of fibrotic component, ill-defined margins without aponeurotic extension, and more than five central and peripheral flow-voids are very likely to be ASPS. • ASPS may be misdiagnosed as intramuscular benign vascular tumor or vascular malformation, which occur in the same age group.

Role of Next-Generation Sequencing as a Diagnostic Tool for the Evaluation of Bone and Soft-Tissue Tumors.

Bone and soft-tissue tumors are in general rare. Diagnosing these tumors is challenging based on the significant number of different tumor entities, the rareness of these tumors, and the considerable morphological heterogeneity which can be found within a single tumor entity. Considering that more than half of the described soft-tissue tumors and approximately 25% of the bone tumors harbor recurrent genetic alterations, the use of auxiliary molecular examinations should be strongly considered. Molecular analyses are important to confirm the diagnosis, to guide treatment, to provide information about prognosis, and to allow patient recruitment for basket trials based on the molecular signature of a tumor. In addition, novel molecular alterations detected by next-generation sequencing (NGS) obtain further insights into the pathogenesis of these rare tumors and allow a more detailed genetic classification. Based on our single-center results of NGS using the Ion AmpliSeq Cancer Hotspot Panel v2 and the Ion AmpliSeq Comprehensive Cancer Panel (Thermo Fisher Scientific) for mutational analyses as well as the Archer FusionPlex Sarcoma Kit (ArcherDX, Inc) to detect gene fusions in 26 genes since early 2016, we have experienced NGS as a very sensitive method to detect genetic alterations. In our experience, the use of the Archer FusionPlex Sarcoma Kit is superior to fluorescent in situ hybridization as an auxiliary tool in the routine workup of soft-tissue and bone tumors.

[Tumor-induced osteomalacia caused by a late-revealing phosphaturic mesenchymal tumor]. / Ostéomalacie secondaire à une tumeur mésenchymateuse phosphaturique de révélation tardive.

INTRODUCTION: Osteomalacia is associated with diffuse pain and multiple fractures and therefore, diagnosis and treatment of this condition are necessary. Clinicians should be aware of an uncommon mechanism of osteomalacia where hypophosphataemia is secondary to renal phosphaturia because of the production by a mesenchymal phosphaturic tumor of FGF-23. This tumor should be localized and removed to cure this tumor-induced osteomalacia. OBSERVATION: A 70-year-old female patient was admitted to explore diffuse pain caused by multiple fractures secondary to osteomalacia. Despite vitamin D supplementation, she remained profoundly hypophosphoremic with major renal phosphaturia. A tumor-induced mechanism was suspected because of high level of FGF-23. It took more than three years of investigation to spot the causal phosphaturic mesenchymal tumor despite annual repetition of indium-labelled scintigraphy and PET-scan. The resection of the tumor, located between two phalanges of the right foot, cured the patient with sustained normal rate of serum level of phosphorus after two years. CONCLUSION: Tumor-induced osteomalacia is a diagnostic challenge because the localization of the tumor may be a long process. Patients should be monitored clinically and imaging studies repeated until a diagnosis is made and the causal tumor removed.

Photodynamic quenched cathepsin activity based probes for cancer detection and macrophage targeted therapy.

Elevated cathepsins levels and activities are found in several types of human cancer, making them valuable biomarkers for detection and targeting therapeutics. We designed small molecule quenched activity-based probes (qABPs) that fluoresce upon activity-dependent covalent modification, yielding cell killing by Photodynamic Therapy (PDT). These novel molecules are highly selective theranostic probes that enable both detection and treatment of cancer with minimal side effects. Our qABPs carry a photosensitizer (PS), which is activated by light, resulting in oxidative stress and subsequent cell ablation, and a quencher that when removed by active cathepsins allow the PS to fluoresce and demonstrate PD properties. Our most powerful and stable PS-qABP, YBN14, consists of a selective cathepsin recognition sequence, a QC-1 quencher and a new bacteriochlorin derivative as a PS. YBN14 allowed rapid and selective non-invasive in vivo imaging of subcutaneous tumors and induced specific tumor macrophage apoptosis by light treatment, resulting in a substantial tumor shrinkage in an aggressive breast cancer mouse model. These results demonstrate for the first time that the PS-qABPs technology offers a functional theranostic tool, which can be applied to numerous tumor types and other inflammation-associated diseases.

[Development of lipoma following a single cupping massage - a case report]. / Auftreten eines Lipoms nach einmaliger Schröpfkopfmassage - ein Fallbericht.

BACKGROUND: The cupping massage is a form of bloodless cupping. This type of cupping is particularly used to treat muscular tension and musculoskeletal pain, such as chronic neck pain; however the data records on mechanisms and potential side effects are not satisfactory. CASE REPORT: In a study on the effectiveness of cupping massage in patients with chronic neck pain, one patient showed a formation of a lipoma in the cupping area after the first treatment session. CONCLUSION: Because of the short time interval between therapy and development of the lipoma, a primary cause is not realistic. This adverse event has not been described in the literature before, and the present report describes the case in summary.

Multifocal infection of mycobacterium other than tuberculosis mimicking a soft tissue tumor of the extremity.

Mycobacterium other than tuberculosis infections rarely develop in healthy individuals, but direct inoculation such as contaminated acupuncture can cause mycobacteriosis even in an immunocompetent host. A 56-year-old woman gradually developed pain on the anterior aspect of the left knee and the distal thigh after hiking without trauma. She received acupuncture for 3 consecutive days on the bilateral knees at the suprapatellar and infrapopliteal areas. After acupuncture, mild localized heat and painful swelling developed around the knees bilaterally. Magnetic resonance imaging (MRI) demonstrated soft tissue masses with a lobulated contour at the prefemoral fat between the suprapatellar pouch and the distal femur and at the proximal tibia behind the knee joint capsule. Fibromatosis, pigmented villonodular synovitis, and soft tissue sarcoma were considered. On pathologic examination, multiple granulomas with lymphoplasmatic infiltration were evident, and acid-fast bacteria staining revealed acid-fast bacilli. A mycobacterial culture confirmed Mycobacterium other than tuberculosis infection, and a polymerase chain reaction-fragment length polymorphism assay identified the isolates as Mycobacterium abscessus. After treatment with appropriate antibiotics, the patient had no evidence of disease and reported no pain during activities of daily living. Acupuncture is growing in prominence in Europe and the United States, and the number of reports on complications increases with its widespread use. Although the risk to an individual patient is difficult to determine, acupuncture may cause serious complications in patients with coagulopathy, heart valve disease, and immune deficiency. In addition, direct inoculation such as contaminated acupuncture can cause mycobacteriosis even in an immunocompetent host.

[Application value of 3T 1H-magnetic resonance spectroscopy in diagnosing tumors of bone and soft tissue].

OBJECTIVE: To study benign and malignant bone and soft tissue tumors with 1H-magnetic resonance spectroscopy (1H-MRS) at 3 Tesla MR scanner and assess the value of 1H-MRS in diagnosing bone and soft tissue tumors and distinguishing benign from malignant tumors. METHODS; Totally 49 patients with clinically and pathologically confirmed bone and soft tissue tumors were enrolled in this study. 1H-MRS was performed before treatment with point-resolved spectroscopy sequence. The imaging characteristics of 1H-MRS for bone and soft tissue tumors were observed and the possible differences between benign and malignant tumors was compared. Since spectra were directly found under single-voxel proton MRS brain examination, the peak height of choline containing compounds (Cho) opposite to the creatine (Cr) and the Cho peak were observed, and then the malignancies of the tumors were judged. Cho/Cr value was calculated and used to distinguishing benign tumors from malignancies. RESULTS: 1H-MRS spectra of bone and soft tissue tumors were different from those of the normal muscles, and such difference also existed between benign and malignant tumors. The Cho peak disappeared or was extremely low among benign tumors. The Cho/Cr values of malignant tumors and benign tumors were 3.13 +/- 0.9 and 1.34 +/- 1.02, respectively (P = 0.02). Using 1.79 as the threshold value, the Cho/Cr value had sensitivity, specificity, and accuracy of 94%, 80%, and 90%, respectively, in diagnosing malignancies. CONCLUSIONS: The increased Cho level, as measured by 1H-MRS, is related with the bone and soft tissue malignant tumor. Cho/Cr value is useful in distinguishing benign tumors from malignancies. 1H-MRS can be an important supplement to the conventional magnetic resonance imaging.

Infected giant lymphangioma circumscriptum treated with a combination therapy.

Lymphangioma circumscriptum is an uncommon benign disorder of skin and subcutaneous tissues characterized by dilated lymphatic channels. It is an uncommon vascular tumor and it rarely becomes infected. We report a 20-year-old man who had an infected giant tumor in his left thigh. After an extensive resection and radiofrequency energy therapy, he recovered well with an acceptable cosmetic result. We followed up the patient for 2 years without any recurrence.

A 9-month-old phosphaturic mesenchymal tumor mimicking the intractable rickets.

Phosphaturic mesenchymal tumor is an extremely rare disease and is frequently associated with oncogenic osteomalacia showing paraneoplastic syndrome, which is characterized by phosphaturia, hypophosphatemia, normocalcemia, and decreased levels of 1,25-dihydroxyvitamin D3 associated with a tumor. A 2-year-old boy, who had a soft tissue tumor on his right thigh and previously diagnosed as myositis ossificans at 9-months-old, was presented with rachitic rosary and mildly enlarged tumor. Biochemical investigations showed hypophosphatemia, hyperphosphaturia, and an increased alkaline phosphatase level of 440 U/l (25-100 U/l), suggesting rickets, which was resistant to vitamin D dietary supplementation. We were certain of intractable rickets because of oncogenic hypophosphatemia and thus decided to excise the soft tissue mass. We observed laboratory improvement of rickets after 2 weeks. On the basis of surgical and histopathological examinations, the tumor was finally diagnosed as the phosphaturic mesenchymal tumor.

[Changes of 3-tesla 31P-MR spectroscopy of bone and soft tissue tumors].

OBJECTIVE: To study the characteristic changes of 31P-MR spectroscopy of bone and soft tissue tumors. METHODS: 41 patients were examined by phosphorus surface coil of 3 tesla MR machine, including 18 benign tumor foci and 28 malignant foci, and adjacent normal muscles. The areas under the peaks of various metabolites in the spectra were measured, including phosphomonoester (PME), inorganic phosphours (Pi), phosphodiester (PDE), phosphocreatine (Pcr), adenosine triphosphate (ATP) gamma, alpha, beta. The ratios of the metabolites to beta-ATP, NTP and Pcr were calculated. Intracellular pH was calculated according to the chemical shift change of Pi relative to Pcr. RESULTS: The ratios of Pcr/PME and PME/NTP in benign and malignant tumor groups were significantly different from those of the normal group (P<0.05). Between benign and malignant tumor groups, the ratios of PME/beta-ATP and PME/NTP were significantly different (P<0.05). CONCLUSION: Pcr/PME and PME/NTP are potential diagnostic indexes of bone and soft tissue tumors. PME/beta-ATP and PME/NTP are potential indexes of differential diagnosis of bone and soft tissue tumors.

[Reduced bone density and bone pain :osteomalacia with hypophospatemia and hypophosphaturia]. / Erniedrigte Knochendichte und Knochenschmerzen : Osteomalazie mit Hypophosphatämie und Hyperphosphaturie.

Two patients aged 24 and 64 years presented at our hospital with similar symptoms including bone pain and muscle weakness. Basic laboratory tests and urinary diagnostics, bone densitometry and bone histology revealed severe osteomalacia with renal phosphate wasting. After the exclusion of other causes an extensive tumor search was performed due to suspected tumor-induced osteomalacia. In one patient a mesenchymal tumor was found in the thigh and completely resected. After surgery the patient showed a rapid recovery from osteomalacia. Because the search was unsuccessful in the other patient phosphorus supplementation in combination with calcitriol was started. Despite continuing renal phosphate wasting a significant increase in bone mineral density was observed.

Dynamic contrast-enhanced magnetic resonance imaging as a predictor of clinical outcome in canine spontaneous soft tissue sarcomas treated with thermoradiotherapy.

PURPOSE: This study tests whether dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) parameters obtained from canine patients with soft tissue sarcomas, treated with hyperthermia and radiotherapy, are predictive of therapeutic outcome. EXPERIMENTAL DESIGN: Thirty-seven dogs with soft tissue sarcomas had DCE-MRI done before and following the first hyperthermia. Signal enhancement for tumor and reference muscle were fitted empirically, yielding a washin/washout rate for the contrast agent and tumor area under the signal enhancement curve (AUC) calculated from 0 to 60 seconds, 90 seconds, and the time of maximal enhancement in the reference muscle. These parameters were then compared with local tumor control, metastasis-free survival, and overall survival. RESULTS: Pretherapy rate of contrast agent washout was positively predictive of improved overall and metastasis-free survival with hazard ratio of 0.67 (P = 0.015) and 0.68 (P = 0.012), respectively. After the first hyperthermia washin rate, AUC60, AUC90, and AUCt-max were predictive of improved overall and metastasis-free survival with hazard ratio ranging from 0.46 to 0.53 (P < 0.002) and 0.44 to 0.55 (P < 0.004), respectively. DCE-MRI parameters were compared with extracellular pH and (31)P MR spectroscopy results (previously published) in the same patients showing a correlation. This suggested that an increase in perfusion after therapy was effective in eliminating excess acid from the tumor. CONCLUSIONS: This study shows that DCE-MRI has utility predicting overall and metastasis-free survival in canine patients with soft tissue sarcomas. To our knowledge, this is the first time that DCE-MRI parameters are predictive of clinical outcome for soft tissue sarcomas.

Massive recurrent synovial sarcoma of the hip: radiologic-histologic correlation in a case of failed magnet therapy.

We report the unusual case of a recurrent, massive synovial sarcoma of the hip, following magnet therapy failure.

[Practice guideline 'Diagnostic techniques for soft tissue tumours and treatment of soft tissue sarcomas (revision)']. / Richtlijn 'Diagnostiek bij wekedelentumoren en behandeling van wekedelensarcomen (herziening)'.

Members of the Dutch working group on soft tissue tumours developed an up-to-standard evidence-based multidisciplinary clinical practice guideline for the diagnosis of soft tissue tumours and the treatment and follow-up of soft tissue sarcomas, in cooperation with the Dutch Association of Comprehensive Cancer Centres and the Dutch Institute for Healthcare Improvement. A soft tissue sarcoma is defined as every non-epithelial tumour that does not originate in haematopoietic or lymphatic system, central nervous system or bone. The guideline lists 'alarm signals' to raise awareness of malignancy and recommends consulting a multidisciplinary team. Non-invasive imaging has to be completed before proceeding to any invasive (diagnostic) procedure or assessment of dissemination. Aspiration cytology can be useful for differentiating between sarcoma and other malignancies. A definite diagnosis is obtained by means of image-guided needle biopsy. Tumours will be classified according to the World Health Organization and graded according to the Federation Nationale des Centres de Lutte Contre le Cancer. Surgical excision with a tumour free margin of 2 cm is the core of therapy, taking into account vital structures when necessary. In case of small superficial tumours (diameter < or = 3 cm) excision biopsy may be justified. Radiotherapy is almost always necessary and certainly indicated when wide margins are impossible even after re-resection. In the case of primary metastatic disease, an individual decision should be taken after multi-disciplinary consultation concerning the possibility of curative or palliative treatment. Neither neo-adjuvant nor adjuvant chemotherapy is standard. Chemotherapy may be useful in metastatic disease. The guideline advises referring patients who are eligible for chemotherapy to a centre and that they should be included in a study protocol.