Metallothionein expression in feline injection site fibrosarcomas.

BACKGROUND: Feline injection site fibrosarcoma is an aggressive and infiltrative tumour arising in the background of chronic inflammation. The aim of this study was to evaluate the expression of metallothionein (I-II) in feline injection site fibrosarcomas and to assess its possible relationships with Ki67 index, inflammation score and tumour grade. The study included 40 feline fibrosarcomas, located in the common injection sites (i.e., interscapular area, thigh, flank), constituting archival diagnostic specimens collected between 2019-2020. Tumours were graded histologically according to the newly proposed soft-tissue sarcoma grading system in cats. Immunohistochemistry was performed to evaluate the expression of Ki67 and metallothionein in tumour cells. RESULTS: The cytoplasmic and sometimes nuclear expression of metallothionein was observed in all tumours grade I, 66.67% of tumours grade II and 55% of tumours grade III. The expression of metallothionein was negatively correlated with tumour grade and inflammation score, while the Ki67 index was positively correlated with tumour grade, inflammation score and necrosis score. CONCLUSION: The downregulation of MT expression in feline injection site fibrosarcomas seems to be connected with an increase in the inflammatory infiltration, hence tumour progression. This is the first study describing metallothionein expression in feline injection site fibrosarcomas.

Tumor morphology and location associate with immune cell composition in pleomorphic sarcoma.

BACKGROUND: Soft-tissue sarcomas (STS) are a rare group of mesenchymal malignancies that account for approximately 1% of adult human cancer. Undifferentiated pleomorphic sarcoma (UPS) is one of the most common subtypes of adult STS. Clinical stratification of UPS patients has not evolved for decades and continues to rely on tumor-centric metrics including tumor size and depth. Our understanding of how the tumor microenvironment correlates to these clinicopathologic parameters remains limited. METHODS: Here, we performed single-cell flow cytometric immune-based profiling of 15 freshly resected UPS tumors and integrated this analysis with clinical, histopathologic, and outcomes data using both a prospective and retrospective cohort of UPS patients. RESULTS: We uncovered a correlation between physiologic and anatomic properties of UPS tumors and the composition of immune cells in the tumor microenvironment. Specifically, we identified an inverse correlation between tumor-infiltrating CD8 + T cells and UPS tumor size; and a positive correlation between tumor-infiltrating CD8 + T cells and overall survival. Moreover, we demonstrate an association between anatomical location (deep or superficial) and frequency of CD4 + PD1hi infiltrating T cells in UPS tumors. CONCLUSIONS: Our study provides an immune-based analysis of the tumor microenvironment in UPS patients and describes the different composition of tumor infiltrating lymphocytes based on size and tumor depth.

Soft-Tissue Sarcoma as a Potential Differential Diagnosis of an Exophytic Soft-Tissue Mass: A Case Report.

The detection of a soft-tissue mass requires a detailed and conscientious examination to make a definitive diagnosis and propose appropriate treatment strategies. Benign mesenchymal tumors occur more frequently than malignant tumors. However, because of their aggressive growth and poor prognosis, sarcomas must always be considered as a potential differential diagnosis. To make a formal diagnosis and plan appropriate surgical treatment, the surgeon should obtain cross-sectional imaging studies and biopsies.

Endoscopic resection of a localized tenosynovial giant cell tumor causing posterior ankle impingement in a 15-year-old athlete: A case report.

Tenosynovial giant cell tumor (TGCT) is a systematically benign but locally aggressive lesion arising from the synovium, tendon sheath or joint bursae. Even in athletes, soft tissue tumors may be the underlying reason or a component of posterior ankle impingement, although the most common mechanism is forceful and repetitive plantar flexion. In this article, we present a case of localized TGCT in a 15-year-old female patient presenting with symptoms of posterior ankle impingement. The preferred technique for treatment was complete local resection via posterior ankle endoscopy. The patient returned to sports at three months and no recurrence was observed on the last follow-up at the first postoperative year. Although rare, soft tissue tumors should be taken into consideration in posterior ankle impingement in athletes. Such benign soft tissue tumors in the posterior ankle can be treated safely and effectively via two-portal posterior endoscopic approach.

An ultrasonographic and electromyographic evaluation of jumping stump possibly due to a neuroma in a patient with transradial amputation: A case report.

BACKGROUND AND OBJECTIVE: Jumping stump is an uncommon movement disorder characterized by involuntary movements and severe neuropathic pain in the stump. The pathophysiology and etiology of this phenomenon have not yet been clearly elucidated, and unfortunately, no proven treatment with successful recovery exists. This report aims to describe a severe painful jumping stump, possibly due to neuromas, in a traumatic transradial amputee. MATERIALS AND METHOD: We performed ultrasound examination of the painful stump depicted neuroma. Electromyographic evaluation of the stump revealed arrhythmic motor unit action potentials (MUAPs) with normal duration and amplitude; other movement disorders, such as myokymia and fasciculations, were excluded. Ultrasound should be preferred to magnetic resonance imaging (MRI) for evaluation of stumps in patients with painful stump because MRI may not be helpful due to motion artefacts. The involuntary movements ceased after surgical excision of the neuroma following failure of conservative treatments. CONCLUSION: This report confirms that neuromas are clearly associated with jumping stump. Ultrasonographic and electromyographic assessments are necessary to reveal the features of this pathology for treatment planning.

FAK Signaling in Rhabdomyosarcoma.

Rhabdomyosarcoma (RMS) is the most common soft tissue sarcoma of children and adolescents. The fusion-positive (FP)-RMS variant expressing chimeric oncoproteins such as PAX3-FOXO1 and PAX7-FOXO1 is at high risk. The fusion negative subgroup, FN-RMS, has a good prognosis when non-metastatic. Despite a multimodal therapeutic approach, FP-RMS and metastatic FN-RMS often show a dismal prognosis with 5-year survival of less than 30%. Therefore, novel targets need to be discovered to develop therapies that halt tumor progression, reducing long-term side effects in young patients. Focal adhesion kinase (FAK) is a non-receptor tyrosine kinase that regulates focal contacts at the cellular edges. It plays a role in cell motility, survival, and proliferation in response to integrin and growth factor receptors' activation. FAK is often dysregulated in cancer, being upregulated and/or overactivated in several adult and pediatric tumor types. In RMS, both in vitro and preclinical studies point to a role of FAK in tumor cell motility/invasion and proliferation, which is inhibited by FAK inhibitors. In this review, we summarize the data on FAK expression and modulation in RMS. Moreover, we give an overview of the approaches to inhibit FAK in both preclinical and clinical cancer settings.

Preoperative Evaluation of Myxofibrosarcoma: Prognostic Value and Reproducibility of Different Features on MRI.

BACKGROUND/AIM: Myxofibrosarcoma (MFS) is characterized by an infiltrative growth pattern. This study aimed to determine the correlation between overall survival (OS) and morphological features of MFS as well as examine the reproducibility of these findings on preoperative magnetic resonance imaging (MRI). PATIENTS AND METHODS: Fifty-eight MFS patients underwent preoperative MR imaging with the following features analysed: i) tumour size, ii) localization, iii) margins, iv) morphology, v) signal characteristics, vi) contrast enhancement, vii) presence and extent of perilesional oedema, and viii) presence of the tail sign. RESULTS: Only circumscribed perilesional oedema was associated with a significantly better survival compared to diffuse oedema (p=0.010), which was found in the majority of cases. The tail sign was found in less than 50% of the cases. Cohen's kappa coefficients confirmed a relatively high interrater variability. CONCLUSION: Perilesional diffuse oedema on MR imaging of MFS is significantly correlated with a poor overall survival. The interrater variability in interpretation of MR examinations varies from slight to substantial agreement. Preoperative MR imaging with detailed planning of the resection seem to be a logical approach to achieve negative resection margins and recurrence-free survival.

Multiple Glomus Tumors in the Left Foot of 41-year-old Woman. A Case Report.

Glomus tumors are very uncommon neoplasms arising from glomus bodies. They differ in the proportion of components, i.e. smooth muscle tissue, vessels and glomus cells. The most common location of this kind of tumor is the subungual area of digits. In other locations, glomus tumors are very rare but have been reported, among others, in bone, lungs, trachea and stomach. Glomus tumors are often misdiagnosed because of diverse clinical presentations. They can be asymptomatic, may lead to cosmetic discomfort, but clinical presentation often involves pain, tenderness and cold hypersensitivity. We present a case of multiple glomus tumor in the foot of a 41-year-old woman. After several surgical consultations, she had been referred for further surgery including possible ampu-tation, which she declined. Simultaneous multiple excisions of the tumors resulted in complete symptomatic relief. This case confirms that glomus tumors should be considered in a patient with multiple lesions producing ex-cruciating pain.

Proliferative fasciitis: A rare cause of disturbances in an adolescent hand.

We report a case of hand soft tissue tumor-proliferative fasciitis (PF)-in a 12-year-old patient that presented as a painful lump causing trigger finger. After meticulous diagnostic workup, a surgical excision led to immediate amelioration of symptoms. PF is a rare benign pseudosarcomatous lesion arising typically in the subcutaneous tissue and fascia in adults. It is very uncommon in the hand. To the best of our knowledge, this is the first report of a trigger finger being caused due to this pathology. In this report, the authors review PF lesions on hands, advice careful evaluation of magnetic resonance imaging features, and recommend surgical management.

Sarcopenia is associated with increased mortality but not complications following resection and reconstruction of sarcoma of the extremities.

BACKGROUND AND OBJECTIVES: Evidence regarding the impact of sarcopenia on operative outcomes in patients with sarcoma is lacking. We evaluated the relationship between sarcopenia and postoperative complications or mortality among patients undergoing tumor excision and reconstruction. ​ METHODS: We retrospectively reviewed 145 patients treated with tumor excision and limb reconstruction for sarcoma of the extremities. Sarcopenia was defined as psoas index (PI) < 5.45 cm2 /m2 for men and <3.85 cm2 /m2 for women from preoperative axial CT. Regression analyses were used to assess the association between postoperative complications or mortality with PI, age, gender, race, body mass index, tumor histology, grade, depth, location, size, and neoadjuvant/adjuvant therapy. RESULTS: There were 101 soft tissue tumors and 44 primary bone tumors. Sarcopenia was present in 38 patients (26%). Sarcopenic patients were older (median age: 72 vs 59 years, P = .0010) and had larger tumors (86.5%, >5 cm vs 77.7%, P = .023). Seventy-three patients experienced complications (51%) and 18 patients died within 1 year. Sarcopenia and metastatic disease were associated with increased 12-month mortality (hazard ratio [HR] = 6.68, P < .001; HR: 8.51, P < .001, respectively) but not complications (HR 1.45, P = .155, odds ratio, 1.32, P = .426, respectively). CONCLUSIONS: Sarcopenia and metastatic disease were independently associated with postoperative mortality but no complications following surgery.

Psychological functioning, coping styles and their relationship to appraisal of physical limitations following invasive surgical procedures for soft-tissue sarcoma: A qualitative study.

BACKGROUND AND OBJECTIVES: This study explored psychological functioning and coping styles in adult patients with soft-tissue sarcoma who underwent surgical procedures in a single expert sarcoma medical center in Canada. METHODS: This is a qualitative study with three formats of data collection. The interview guide was based on theoretical health-related quality of life model. We began the investigation with 2 online and 2 in-person focus groups. Four individual semistructured interviews were added to further explore emerging themes. Data were analyzed using inductive thematic networks approach. RESULTS: Twenty-eight adults (13 female, 24-75 years of age) participated. In the domain of psychological functioning we identified three main themes; changes in mood, worry, and body image concerns. In the domain of coping styles, we identified four adaptive coping styles; positive reframing and optimism, finding a purpose, being proactive, and using humor. Among the maladaptive coping styles, we found passive acceptance, and avoidance and denial. CONCLUSIONS: Psychological well-being can be contingent on physical functioning and coping styles in adults with soft-tissue sarcoma. Both psychological and physical function impact quality of life. Patients with more physical limitations, psychological distress and maladaptive coping styles should be monitored for their well-being.

Patients with head and neck cancer: Are they frailer than patients with other solid malignancies?

OBJECTIVE: We aimed to compare frailty status between patients with head and neck cancer (HNC) and other solid malignancies. METHODS: Data collection was prospective, and the following were compared between cohorts at baseline: patient and tumour characteristics, Charlson Comorbidity Index (CCI), Groningen Frailty Indicator (GFI), Mini Mental State Examination (MMSE), Activities of Daily Living (ADLs), Instrumental ADLs (IADLs), Timed Up and Go (TUG) and Quality of Life (QoL). Univariate and multivariate logistic regression analyses were performed, and odds ratios (ORs) with their 95% confidence intervals (95% CIs) were estimated. RESULTS: In total, 242 patients with HNC and 180 with other oncology diagnoses were enrolled, of whom 32.6% and 21.8% were frail according to the GFI respectively. Comorbidity scores were not significantly different between the cohorts (7.4% vs. 13.1%; OR 0.54; 95% CI 0.28-1.02). In the univariate analysis, the GFI was significantly worse in the HNC cohort (OR 1.74; 95% CI 1.11-2.71). However, in the multivariate analysis, the MMSE, TUG and global QoL were significantly worse in the HNC cohort, with ORs of 20.03 (95% CI 2.44-164.31), 11.56 (95% CI 1.86-71.68) and 0.98 (95% CI 0.97-1.00) respectively. CONCLUSION: Patients with HNC appear to be frailer than patients with other solid malignancies despite comparable levels of comorbidity.

Are Accelerometer-based Functional Outcome Assessments Feasible and Valid After Treatment for Lower Extremity Sarcomas?

BACKGROUND: Aspects of physical functioning, including balance and gait, are affected after surgery for lower limb musculoskeletal tumors. These are not routinely measured but likely are related to how well patients function after resection or amputation for a bone or soft tissue sarcoma. Small, inexpensive portable accelerometers are available that might be clinically useful to assess balance and gait in these patients, but they have not been well studied. QUESTIONS/PURPOSES: In patients treated for lower extremity musculoskeletal tumors, we asked: (1) Are accelerometer-based body-worn monitor assessments of balance, gait, and timed up-and-go tests (TUG) feasible and acceptable? (2) Do these accelerometer-based body-worn monitor assessments produce clinically useful data (face validity), distinguish between patients and controls (discriminant validity), reflect findings obtained using existing clinical measures (convergent validity) and standard manual techniques in clinic (concurrent validity)? METHODS: This was a prospective cross-sectional study. Out of 97 patients approached, 34 adult patients treated for tumors in the femur/thigh (19), pelvis/hip (3), tibia/leg (9), or ankle/foot (3) were included in this study. Twenty-seven had limb-sparing surgery and seven underwent amputation. Patients performed standard activities while wearing a body-worn monitor on the lower back, including standing, walking, and TUG tests. Summary measures of balance (area [ellipsis], magnitude [root mean square {RMS}], jerkiness [jerk], frequency of postural sway below which 95% of power of acceleration power spectrum is observed [f95 of postural sway]), gait [temporal outcomes, step length and velocity], and TUG time were derived. Body-worn monitor assessments were evaluated for feasibility by investigating data loss and patient-reported acceptability and comfort. In addition, outcomes in patients were compared with datasets of healthy participants collected in parallel studies using identical methods as in this study to assess discriminant validity. Body-worn monitor assessments were also investigated for their relationships with routine clinical scales (the Musculoskeletal Tumour Society Scoring system [MSTS], the Toronto Extremity Salvage Score [TESS], and the Quality of life-Cancer survivors [QoL-CS)] to assess convergent validity and their agreement with standard manual techniques (video and stopwatch) to assess concurrent validity. RESULTS: Although this was a small patient group, there were initial indications that body-worn monitor assessments were well-tolerated, feasible to perform, acceptable to patients who responded (95% [19 of 20] of patients found the body-worn monitor acceptable and comfortable and 85% [17 of 20] found it user-friendly), and produced clinically useful data comparable with the evidence. Balance and gait measures distinguished patients and controls (discriminant validity), for instance balance outcome (ellipsis) in patients (0.0475 m/s [95% confidence interval 0.0251 to 0.0810]) was affected compared with controls (0.0007 m/s [95% CI 0.0003 to 0.0502]; p = 0.001). Similarly gait outcome (step time) was affected in patients (0.483 seconds [95% CI 0.451 to 0.512]) compared with controls (0.541 seconds [95% CI 0.496 to 0.573]; p < 0.001). Moreover, body-worn monitor assessments showed relationships with existing clinical scales (convergent validity), for instance ellipsis with MSTS (r = -0.393; p = 0.024). Similarly, manual techniques showed excellent agreement with body-worn monitor assessments (concurrent validity), for instance stopwatch time 22.28 +/- 6.93 seconds with iTUG time 21.18 +/- 6.23 seconds (intraclass correlation coefficient agreement = 0.933; p < 0.001). P < 0.05 was considered statistically significant. CONCLUSIONS: Although we had a small, heterogeneous patient population, this pilot study suggests that body-worn monitors might be useful clinically to quantify physical functioning in patients treated for lower extremity tumors. Balance and gait relate to disability and quality of life. These measurements could provide clinicians with useful novel information on balance and gait, which in turn could guide rehabilitation strategies. LEVEL OF EVIDENCE: Level III, diagnostic study.

Health-related quality of life of Brazilian children and adolescents with benign and malignant solid tumours: A prospective cohort study during the first year after hospital admission.

INTRODUCTION: This study aims to assess the impact of paediatric benign and malignant solid tumours and its treatment on the health-related quality of life of children and adolescents who were followed up in a Reference Center in Pediatric Oncology in Rio de Janeiro. METHODS: It is a prospective cohort study. Quality of life assessment was performed using the PedsQL™ 4.0 Generic Core Scales and PedsQL™ 3.0 Cancer Module protocols three times: during hospital admission (T1), 6 months after admission (T2) and 1 year after admission (T3). RESULTS: We evaluated 132 patients, 59 men and 73 women, aged 2-17 years. In PedsQL™4.0, the Emotional Functioning scale was the one with the worst scores, while the scores on the Social Functioning scale was the best. In PedsQL™ 3.0, the worst domains were Procedural Anxiety and Worry. Patients with malignant bone tumours had the worst health-related quality of life. The group who received only surgery had better results. Total scores of PedsQL™4.0 and PedsQL™ 3.0 improved between T1 and T3. CONCLUSION: Children and adolescents with malignant and benign neoplasms undergo changes in quality of life as a result of the disease and treatment, but an improvement has been observed over time.

An exceptional case of malignant glomus tumor and a review of the literature.

Malignant glomus tumors (MGTs) are exceptional but pose diagnostic and therapeutic challenges. Wide resection is the recommended treatment method, however, no data are available concerning adjuvant therapies. We present an exceptional case of extradigital deep-seated MGT of the forearm, with an exceptional bone infiltration. Despite being treated with wide resection, the patient had an optimal functional outcome, no functional loss, no motor or sensitive deficits and has returned to his full daily activity.

Synovial hemangioma of the knee joint in pediatrics: our case series and review of literature.

BACKGROUND: Synovial hemangioma is a benign intra-articular tumor. This condition is rare and unfamiliar soft tissue tumor to most orthopedic surgeons. Delayed diagnosis causes osteoarthritic damage and the destruction of joint structures due to infiltrating tumor growth. We discuss the patterns of tumor location and the appropriate surgical procedure for this condition. METHODS: Ten patients were treated surgically in our department. These comprised five males and five females ranging in age from 0 to 17 years (average age 12.4 years). Preoperative diagnosis was made using clinical findings, plain radiographs and magnetic resonance imaging. The follow-up time after surgery was at least 3 years. RESULTS: The main symptom was pain. Three cases revealed hemarthrosis. The range of motion of the affected knee joint was limited in five cases. The average time between onset of pain and diagnosis was 3 years. Tumor location was classified into three patterns: (1) anterior patellofemoral joint type in five, (2) posterior popliteal type in two and (3) diffuse proliferation type in two. Open arthrotomy with synovectomy was performed in all cases. No tumor recurrences were experienced after a minimum follow-up of 3 years. CONCLUSION: Clinical symptom and magnetic resonance imaging are helpful to obtain the diagnosis and determine the extent of the lesion. Depending on the tumor location, synovial hemangioma in the knee joint can be classified into patellofemoral, popliteal and diffuse types. Open arthrotomy with sufficient tumor and synovectomy is important to prevent tumor recurrence.

Miscorrelation of Functional Outcome and Sociooccupational Status of Childhood, Adolescent, and Young Adult Generation With Bone and Soft Tissue Sarcoma Patients.

Few studies have examined the relationship between functional outcome and sociooccupational or psychological status in adolescent and young adults (AYA) generation and childhood sarcoma patients. We retrospectively analyzed clinical (prognostic and functional) and sociooccupational outcomes in 50 patients; 22 children aged under 14 years and 28 AYAs generation (15 to 29 y). There were 35 cases of bone sarcomas and 15 of soft tissue sarcomas. Limb-sparing surgery was performed in 30 of 37 extremity cases. The most prevalent problems among patients were as follows: limited activities; drop-out or delayed studies among high school and college students; limitation in job searching; and changes in social relationships. These problems were unaffected by limb-sparing. Regression analysis between functional and sociooccupational disability showed that the correlation coefficient was significant (P=0.005) in all limb-salvaged patients, but there was no significant correlation among osteosarcoma patients (P=0.07). These findings suggest that quality of life is a multidimensional measure: it depends on physical status, spiritual health, and social well-being of both patients and family members. To overcome the disadvantages of this type of disease, it is essential to provide comprehensive care at the earliest convenience using multidimensional approaches.

Painful Traumatic Neuromas in Subcutaneous Fat: Visibility and Morphologic Features With Ultrasound.

OBJECTIVES: Subcutaneous neuromas usually result from trauma and may lead to dissatisfaction in patients with a trigger point, loss of sensitivity in the relevant territory of innervation, and spontaneous neuropathic pain. Confirming clinically suspected cases of neuroma may prove difficult. The objective of this study was to evaluate the visibility and morphologic features of traumatic subcutaneous neuromas of the limbs with ultrasound (US). METHODS: Between January 2012 and August 2016, 38 consecutive patients clinically suspected of having subcutaneous neuromas were investigated with US. The diagnosis was confirmed on the basis of a focal morphologic abnormality of the nerve associated with trigger pain. Each neuroma was classified into 1 of 3 subtypes based on its injury pattern. The subtypes were terminal neuroma, spindle neuroma, and scar encasement, either isolated or associated with these subtypes. RESULTS: Forty-four lesions were found in the 38 patients, including 29 spindle neuromas (65.9%), 14 terminal neuromas (31.8%) and 1 scar encasement with no nerve caliber abnormality (2.3%). Fifteen neuromas (35% of all neuromas) were associated with scar encasement. In 13 cases that required surgery, the diagnosis of neuroma or scar encasement could be surgically proven and confirmed the validity of the US findings. CONCLUSIONS: Ultrasound can be used to show and classify subcutaneous nerves of the upper and lower limbs with high accuracy. The US trigger sign provides an indication of neuroma involvement in pain. This modality can play a substantial role both in the preoperative planning of neuroma surgery and in therapeutic US-guided procedures.

Bilateral Orbital Soft-Tissue Metastases from Renal Neuroendocrine Tumor: Successful Theranostic Application of 68Ga/177Lu-DOTATATE with Improvement of Vision.

A gratifying clinical response obtained in the setting of bilateral orbital metastases from renal neuroendocrine tumor is reported. Methods: A 53-y-old man diagnosed with renal neuroendocrine tumor (MIB1 index, 4%), with symptoms of skeletal and abdominal pain, proptosis, and a decrease in vision of the left eye, was found to harbor bilateral orbital soft-tissue lesions on 68Ga-DOTATATE PET/CT and MRI in addition to widespread metastatic skeletal lesions and metastatic lymph nodal disease. Despite radiotherapy to the left eye (20 Gy) and long-acting octreotide therapy for 18 mo, his symptoms worsened, with an increase in serum chromogranin A level, and he was considered for 177Lu-DOTATATE peptide receptor radionuclide therapy (PRRT). Results: There was a significant improvement in skeletal pain, proptosis, and vision after 4 cycles of PRRT (cumulative dose of 22.2 GBq), stable disease on scanning, and a decrease in serum chromogranin A (from 150 to 36.39 ng/mL), with progression-free survival at 18 mo. Conclusion: PRRT through theranostic application of 68Ga/177Lu-DOTATATE was thus helpful in this uncommon clinical setting.

Soft-tissue vascular malformations and tumors. Part 1: classification, role of imaging and high-flow lesions. / Malformaciones vasculares y tumores de partes blandas. Parte 1: clasificación, papel de las pruebas imagen y lesiones de alto flujo.

Vascular malformations and tumors, also known as "vascular anomalies", comprise an extensive variety of lesions involving all parts of the body. Knowledge of their classification and imaging characteristics is paramount. Whereas hemangiomas are benign vascular tumors, characterized by cellular proliferation and hyperplasia; vascular malformations are not real tumors and characteristically exhibit normal endothelial turnover. Vascular malformations are classified according to the predominant vascular channel as arterial, capillary, venous, lymphatic, or mixed. Ultrasound and MRI are the main imaging modalities used in the diagnosis and classification of the vascular anomalies. In this series of two articles we review the classification of vascular anomalies, describe the role of imaging, summarize their distinctive histopathogenic, clinical and imaging features, and discuss the treatment options. On the first article we discuss the high-flow lesions, whereas the slow-flow lesions will be reviewed on the second. Complex syndromes with associated vascular tumors and malformations will be also presented.