Detection of Muscular Metastasis in a Case of Parathyroid Carcinoma Using 18 F-FAPI-04 PET/CT.

ABSTRACT: A 46-year-old woman underwent surgery for parathyroid carcinoma 2 years ago. During follow-up, the patient presented with elevated parathyroid hormone (127.50 pg/mL; normal, 15-65). No abnormal uptake of 18 F-FDG or 11 C-choline was observed on 18 F-FDG and 11 C-choline PET/CT imaging. The patient was enrolled in a clinical trial for 18 F-FAPI PET/CT imaging, revealing a lesion with intense focal uptake within the left sternocleidomastoid muscle. The patient underwent surgery. Postoperative pathology and immunohistochemical analysis confirmed parathyroid carcinoma metastasis.

Intramuscular mesenchymal chondrosarcoma surrounded by a split fat sign mimicking a benign lesion.

Mesenchymal chondrosarcoma (MCS) is an aggressive malignant mesenchymal tumour of uncertain differentiation. This is rare, accounting for 2%-4% of chondrosarcomas. Its peak incidence is in the second and third decades, though it can occur at any age. These tumours show a widespread distribution, mainly in bone, but with approximately 40% affecting somatic soft tissue. We present a case of MCS arising within the soleus muscle. The lesion was surrounded by a split-fat sign/fatty rind which is a typical feature of peripheral nerve sheath tumours or other benign intramuscular tumours. However, percutaneous biopsy showed MCS. We highlight how perilesional fat is not exclusive to benign intramuscular lesions and, although much less common, can be associated with malignant lesions. This is, to the best of our knowledge, the first reported case of MCS presenting with a split-fat sign at MRI.

Pediatric intramuscular hemangioma in the submandibular triangle and other musculoskeletal presentations: A pediatric case series.

BACKGROUND: Intramuscular hemangiomas (IMH) account for 0.8 % or less of all benign soft tissue tumors in the general population. Due to their uncommon nature, especially in the head and neck, they are often misdiagnosed and not included in the differential diagnosis. METHODS: This study describes a case series of eleven pediatric patients with a diagnosis of IMH through a retrospective review of the electronic health records and archival records in the Department of Pathology at Children's Hospital of Colorado (CHCO). RESULTS: The index case had a unique presentation in the submandibular triangle, while the remaining ten cases are appendicular and thoracolumbar in nature. CONCLUSIONS: This case series contributes to the sparse scientific literature available regarding IMH, particularly in its head and neck presentation as relevant to otolaryngologists.

Cortical hypertrophy in intramuscular hemangioma mimicking bone tumor.

Although hemangiomas are the most common soft tissue tumors, intramuscular hemangiomas account for only 0.8% of all vascular tumors. These lesions are rarely located adjacent to the bone and cause changes in the adjacent bone. They are often mistakenly diagnosed as bone tumors. In this study, a case of a 19-year-old male patient with intramuscular hemangioma causing cortical thickening was reported.

Unique Case of Rare Non-Neural Granular Cell Tumor of the Rectus Abdominis Muscle.

Background and Objectives: Our report contributes a unique case of a non-neural GCT occurring in an unusual location, with its development during pregnancy adding to its rarity. Materials and Methods: Granular cell tumors (GCTs), also known as Abrikossoff's tumors, are rare neoplasms of Schwann cell origin with predominantly benign behavior. We present a case of a 29-year-old female with a non-neural variant of a GCT discovered incidentally during a cesarean section, situated on the posterior surface of the rectus abdominis muscle. Results: Histologically, the tumor exhibited features consistent with a benign non-neural GCT, confirmed through an immunohistochemical analysis. Despite the atypical presentation and challenging surgical removal due to prior scarring, the patient experienced no postoperative complications and showed no signs of recurrence during follow-up. Conclusions: This case highlights the importance of considering GCTs in differential diagnoses, particularly in unusual anatomical locations, and underscores the favorable prognosis associated with timely surgical intervention.

Multispecialty Management of Metastatic Colon Adenocarcinoma Involving the Extraocular Muscles: Primary Excision and Simultaneous Treatment of Strabismus With a Review of the Literature.

Metastatic colon adenocarcinoma involving the extraocular muscles is extremely rare. It usually develops following the diagnosis of the systemic disease and therefore, management and treatment require a multispecialty approach. Within this manuscript, we provide a summary of cases of orbital metastasis secondary to colon cancer. We further discuss a detailed case of a 42-year-old male patient who developed recent-onset diplopia in the left gaze. Orbital CT imaging showed a localized, well-circumscribed enlargement of the right medial rectus muscle. The biopsy of the right medial rectus showed adenocarcinoma originating from the gastrointestinal system. Further workup revealed colon adenocarcinoma with multiple metastatic sites. The patient started systemic chemotherapy. After 2 months of chemotherapy (5-fluouracil, oxaliplatin, irinotecan, and leucovorin), all systemic metastatic sites regressed; however, his medial rectus muscle continued to grow, causing compressive optic neuropathy. The patient underwent excisional biopsy of the right medial rectus muscle with simultaneous repair of the strabismus with transposition of superior and inferior recti muscles. He continued with systemic chemotherapy. Follow up in 1 year revealed no local orbital tumor recurrence with excellent visual acuity and no diplopia in primary gaze.

Early Diagnosis of Rare Diaphragmatic Synovial Sarcoma in a Pediatric Patient With Epigastric Pain Using Point-of-Care Ultrasound.

ABSTRACT: Synovial cell sarcoma is a rare mesenchymal tumor that typically originates from the soft tissues of the extremities of young adults. Only 3 cases of primary diaphragmatic synovial cell sarcoma have been described in the literature: 2 in adult males and 1 in a 12-year-old pediatric patient. 1-3 When this tumor is found in the mediastinum or pericardial region, prognosis is historically poor because of the advanced disease stage at time of diagnosis. The surgical course and pathology have been described in this 12-year-old boy. 3 This is the first case, to our knowledge, of the use of cardiac point-of-care ultrasound in the early identification and diagnosis of a primary diaphragmatic synovial sarcoma in a pediatric patient.

Laparoscopic resection of a rare diaphragmatic haemangioma: a case report.

This case report describes the laparoscopic resection of a rare diaphragmatic haemangioma. A 45-year-old male patient was diagnosed incidentally with a left subphrenic mass by computed tomography. Laparoscopic left subphrenic mass excision was performed under general anaesthesia. A phrenic haemangioma was confirmed by postoperative pathology. Tumours originating in the diaphragm are rare, with only approximately 200 cases reported in the past century. The diaphragmatic tumour was determined to be primary because intraoperative imaging showed that the tumour was relatively isolated and had no obvious relationship with the surrounding tissues and organs.

A case of intramuscular lumbar myxoma: Uncertainty in the preoperative diagnosis of a spinal soft tissue tumour.

We report an uncommon case of a 76-year-old woman who presented with lower back pain, an intermittent L5 radiculopathy and a right palpable paraspinal mass. Imaging studies revealed a 7-cm lumbar paraspinal pseudo-cystic soft tissue tumour developed in the paravertebral musculature, without a clear radiological diagnosis. Gross total surgical resection was performed, resulting in complete resolution of pain. Histopathological studies revealed an intramuscular (IM) myxoma. With a low positive predictive value of radiological work-up and a poor yield of percutaneous biopsies, surgery remains the mainstay treatment for these rare soft tissue tumours of the lumbar spine. Intramuscular myxomas show excellent postoperative results.

CRTC1-SS18 Fusion Sarcoma With Aberrant Anaplastic Lymphoma Kinase Expression.

Undifferentiated small round cell sarcoma (USRCS) represents a highly heterogeneous group of tumors. A variety of specific gene fusions of USRCS have been reported, including CIC-FOXO4, CIC-NUTM1, BCOR-MAML3, and ZC3H7B-BCOR. Here we report a case of sarcoma harboring a rare recurrent CRTC1-SS18 gene fusion, which was considered as USRCS previously. This sarcoma was composed of nests of small round cells encapsulated in a fibrous stroma. Foci of necrosis and hemorrhage were observed in the tumor. Immunohistochemistry for anaplastic lymphoma kinase showed diffuse positivity. RNA-seq results revealed a chromosomal translocation of CRTC1 gene exon 1 on chromosome 19 with SS18 gene exon 2 on chromosome 18. Thereafter, fluorescence in-situ hybridization confirmed the presence of SS18 gene and CRTC1 gene break-apart, which manifested as the splitting of red and green signals into 2 parts. A previous study showed that CRTC1-SS18 fusion sarcoma and EWSR1-CREB1 fusion angiomatoid fibrous histiocytoma were clustered close in the expression profile. However, whether CRTC1-SS18 fusion sarcomas represent a high malignancy has been a matter of debate. Our study is a worthy addition to the series of rare rearrangements associated with sarcomas and may be of therapeutic relevance.

Imaging features of skeletal muscle lymphoma: a case report and literature review.

BACKGROUND: Diffuse large B cell lymphoma (DLBCL) is the most common type of non-Hodgkin lymphoma (NHL), occurring predominantly in older people. Skeletal muscle lymphoma is a rare form of DLBCL, most frequently affecting the thigh, upper extremities, calf, and pelvis. CASE PRESENTATION: We report a case of skeletal muscle DLBCL that was diagnosed using ultrasound (US)-guided biopsy. A 70-year-old man presented with progressive swelling and pain in the left lower extremity and an elevated erythrocyte sedimentation rate (ESR) and serum C-reactive protein (CRP), ferritin, and CA125 levels. US, magnetic resonance imaging (MRI), and computed tomography (CT) showed diffuse lesions in several muscles of the left lower extremity. Positron emission tomography/CT (PET/CT) showed FDG-uptake in the affected muscles. The patient was treated with chemotherapy and achieved a good response. A systematic review of the literature published between 1992 and 2019 was conducted to investigate the role of imaging, including imaging-guided biopsy, in the diagnosis of skeletal muscle lymphoma. CONCLUSIONS: Skeletal muscle lymphoma is rare. US and MRI features include enlargement of muscular structures, with preservation of the architecture of the tissue and surrounding anatomical structures. Definitive diagnosis relies on histological and immunohistological analysis of a sample obtained through imaging-guided biopsy.

An unusual location of a cavernous hemangioma: a case report.

Hemangiomas are benign vascular tumors that most often affect the skin, mucous membranes, subcutaneous tissues, bone and on rare occasions muscles. In the head and neck region, the masseter and trapezius muscles are most often affected; the temporalis muscle involvement is extremely rare. It is a childhood pathology that rarely occurs in adults. We report a case of a cavernous hemangioma in a 37-year-old female. Through this case and in the light of literature we focus on the clinicopathological aspects of this tumor and the rarity of this location.

Adjunct diagnostic strategies in improving diagnostic yields in image-guided biopsies of musculoskeletal neoplasms-A cost-effectiveness analysis.

BACKGROUND: Routine use of adjunct intraprocedural fresh frozen biopsy (FFP) or point-of-care (POC) cytology at the time of image-guided biopsy can improve diagnostic tissue yields for musculoskeletal neoplasms, but these are associated with increased costs. OBJECTIVE: This study aimed to ascertain the most cost-effective adjunctive test for image-guided biopsies of musculoskeletal neoplasms. METHODS: This expected value cost-effectiveness microsimulation compared the payoffs of cost (2020 United States dollars) and effectiveness (quality-adjusted life, in days) on each of the competing strategies. A literature review and institutional data were used to ascertain probabilities, diagnostic yields, utility values, and direct medical costs associated with each strategy. Payer and societal perspectives are presented. One- and two-way sensitivity analyses evaluated model uncertainties. RESULTS: The total cost and effectiveness for each of the strategies were $1248.98, $1414.09, $1980.53, and 80.31, 79.74, 79.69 days for the use of FFP, permanent pathology only, and POC cytology, respectively. The use of FFP dominated the competing strategies. Sensitivity analyses revealed FFP as the most cost-effective across all clinically plausible values. CONCLUSIONS: Adjunct FFP is most cost-effective in improving the diagnostic yield of image-guided biopsies for musculoskeletal neoplasms. These findings are robust to sensitivity analyses using clinically plausible probabilities.

An unusual extranodal natural killer/T-cell lymphoma presenting as chronic laryngitis: A case report.

RATIONALE: Nasal-type, extranodal natural killer (NK)/T-cell lymphoma is a rare lymphoma. The tumor usually shows ulcerative and necrotic lesions in the nasal cavities and sinuses. Tissue involvement outside the nasal cavity is uncommon. PATIENT CONCERN: We describe a 30-year-old man with a 2-month history of hoarseness, weight loss, and dyspnea. DIAGNOSIS: Magnetic resonance image (MRI) showed edema of the larynx with obliteration of the airway. Laryngoscopic examination described necrotic tissue in the glottis and larynx. The biopsy showed chronic, necrotizing laryngitis, with no granulomas, vasculitis, or atypical cells. The immunologic and microbiologic study was negative. Later, after immunosuppressive therapy, the patient presented erythema and diffuse enlargement of the right arm. MRI showed myositis of the biceps and brachial muscles. Infection was rule out, and direct microscopy showed an extensive muscle infiltration by mononuclear cells and abundant mitosis. Immunohistochemistry was positive for CD3, CD8, Ki 67 (90%), and CD56 compatible with extranodal NK/T cell lymphoma. INTERVENTIONS: The patient initially received immunosuppression treatments (corticoids, cyclofosfamide, and Rituximab) with relapsing episodes. When lymphoma was diagnosed, chemotherapy was started. OUTCOMES: The patient died during chemotherapy. LESSONS: Nasal-type, extranodal NK/T-cell lymphoma should be suspected even when there are no classical findings of neoplasms on histology. Immunohistochemistry is mandatory to rule it out.

Practice Patterns and Pain Outcomes for Targeted Muscle Reinnervation: An Informed Approach to Targeted Muscle Reinnervation Use in the Acute Amputation Setting.

BACKGROUND: Targeted muscle reinnervation (TMR) and regenerative peripheral nerve interface (RPNI) procedures have been shown to improve patient-reported outcomes for the treatment of symptomatic neuromas after amputation; however, the specific indications and comparative outcomes of each are unclear. The primary research questions were what complement of nerves most frequently requires secondary pain intervention after conventional amputation, whether this information can guide the focused application of TMR and RPNI to the primary amputation setting, and how the outcomes compare in both settings. METHODS: We performed a retrospective review of records for patients who had undergone lower-extremity TMR and/or RPNI at our institution. Eighty-seven procedures were performed: 59 for the secondary treatment of symptomatic neuroma pain after amputation and 28 for primary prophylaxis during amputation. We reviewed records for the amputation level, TMR and/or RPNI timing, pain scores, patient-reported resolution of nerve-related symptoms, and complications or revisions. We evaluated the relationship between the amputation level and the frequency with which each transected nerve required neurologic intervention for pain symptoms. RESULTS: The mean pain score decreased after delayed TMR or RPNI procedures from 4.3 points to 1.7 points (p < 0.001), and the mean final pain score (and standard deviation) was 1.0 ± 1.9 points at the time of follow-up for acute procedures. Symptom resolution was achieved in 92% of patients. The sciatic nerve most commonly required intervention for symptomatic neuroma above the knee, and the tibial nerve and common or superficial peroneal nerve were most problematic following transtibial amputation. None of our patients required a revision pain treatment procedure after primary TMR targeting these commonly symptomatic nerves. Failure to address the tibial nerve during a delayed procedure was associated with an increased risk of unsuccessful TMR, resulting in a revision surgical procedure (odds ratio, 26 [95% confidence interval, 1.8 to 368]; p = 0.02). CONCLUSIONS: There is a consistent pattern of symptomatic nerves that require secondary surgical intervention for the management of pain after amputation. TMR and RPNI were translated to the primary amputation setting by using this predictable pattern to devise a surgical strategy that prevents symptomatic neuroma pain. LEVEL OF EVIDENCE: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Intramuscular myxoma of the longus colli mistaken for a cervical rootlet schwannoma.

An 86-year-old woman was referred to the otolaryngology clinic for a 1-year history of a painless, slow-growing neck mass. Physical examination showed a fixed, immobile right level II neck mass with normal vocal cord movement. MRI demonstrated a lobulated mass laterally displacing the carotid vessels, consistent with a schwannoma. Despite the pathognomonic radiographic findings for schwannoma, core needle biopsy of the mass was consistent with intramuscular myxoma (IM), which rarely presents in the head and neck region. After multiple years of slow growth with bulging into the pharynx, the patient ultimately underwent surgery to reduce the risk of airway compromise. The location of this IM together with its unusual imaging appearance is a unique finding in the head and neck and adds to the differential diagnoses for neck masses displacing the carotid sheath.

Will virtual multidisciplinary team meetings become the norm for musculoskeletal oncology care following the COVID-19 pandemic? - experience from a tertiary sarcoma centre.

BACKGROUND: Like with all cancers, multidisciplinary team (MDT) meetings are the norm in bone and soft tissue tumour (BST) management too. Problem in attendance of specialists due to geographical location is the one of the key barriers to effective functioning of MDTs. To overcome this problem, virtual MDTs involving videoconferencing or telemedicine have been proposed, but however this has been seldom used and tested. The COVID-19 pandemic forced the implementation of virtual MDTs in the Oxford sarcoma service in order to maintain normal service provision. We conducted a survey among the participants to evaluate its efficacy. METHODS: An online questionnaire comprising of 24 questions organised into 4 sections was circulated among all participants of the MDT after completion of 8 virtual MDTs. Opinions were sought comparing virtual MDTs to the conventional face-to-face MDTs on various aspects. A total of 36 responses were received and were evaluated. RESULTS: 72.8% were satisfied with the depth of discussion in virtual MDTs and 83.3% felt that the decision-making in diagnosis had not changed following the switch from face-to-face MDTs. About 86% reported to have all essential patient data was available to make decisions and 88.9% were satisfied with the time for discussion of patient issues over virtual platform. Three-fourths of the participants were satisfied (36.1% - highly satisfied; 38.9% - moderately satisfied) with virtual MDTs and 55.6% of them were happy to attend MDTs only by the virtual platform in the future. Regarding future, 77.8% of the participants opined that virtual MDTs would be the future of cancer care and an overwhelming majority (91.7%) felt that the present exercise would serve as a precursor to global MDTs involving specialists from abroad in the future. CONCLUSION: Our study shows that the forced switch to virtual MDTs in sarcoma care following the unprecedented COVID-19 pandemic to be a viable and effective alternative to conventional face-to-face MDTs. With effective and efficient software in place, virtual MDTs would also facilitate in forming extended MDTs in seeking opinions on complex cases from specialists abroad and can expand cancer care globally.

Ovarian adenocarcinoma with metastases in a white rhinoceros.

A 36-y-old white rhinoceros (Ceratotherium simum) was presented with respiratory distress, sanguineous vaginal exudate, and anorexia. The clinical signs progressed over 40 d, and the rhinoceros died. Autopsy revealed significant ascites; a unilateral, 12.5-cm diameter, polypoid mass in the left ovary; a white, firm transmural mass in the right uterine horn; a white, friable mass in the lung; and white-to-tan, friable small nodules in the diaphragm. Histologic examination revealed similar neoplastic cells in the masses in all 4 locations, composed predominantly of epithelial cells proliferating in a tubulopapillary pattern with significant nuclear atypia and numerous atypical mitotic figures (18-42 per 2.37 mm2). Immunohistochemistry for CK7 (cytokeratin 7) and CK20 (cytokeratin 20) suggest that the ovarian, pulmonary, and diaphragmatic lesions were of ovarian origin and that the ovary was the primary tumor site.

Tumor-like Lesions of Bone and Soft Tissues and Imaging Tips for Differential Diagnosis.

In the musculoskeletal system, tumor-like lesions may present similar imaging findings as bone and soft tissue tumors and can be defined as tumors on radiologic examinations. Misinterpretation of the imaging findings can lead to inappropriate clinical management of the patient.There is still some debate regarding the pathophysiology and origin of tumor-like lesions that include congenital, developmental, inflammatory, infectious, metabolic, reactive, posttraumatic, post-therapeutic changes, and some miscellaneous entities causing structural changes. Although tumor-like lesions are historically defined as non-neoplastic lesions, some of them are classified as real neoplasms.We discuss a spectrum of entities mimicking tumors of bone and soft tissues that include various non-neoplastic diseases and anatomical variants based on imaging findings.