Histiocyte-rich rhabdomyoblastic tumor: a clinicopathological and molecular genetic analysis / 中华病理学杂志

Objective: To investigate the clinicopathologic and molecular genetic characteristics, diagnosis, differential diagnosis, treatment and prognosis of histiocyte-rich rhabdomyoblastic tumor (HRRMT). Methods: The clinical data of two cases of HRRMT diagnosed in Fujian Provincial Hospital and Fujian University of Traditional Chinese Medicine Affiliated People's Hospital from 2020 to 2021 were collected. Histopathology and immunohistochemical (IHC) staining were used to assess morphological changes; the genetic changes were analyzed with next-generation sequencing. The relevant literature was reviewed. Results: Both cases showed well-defined solid nodules and soft masses. Microscopically, the tumors had a fibrous pseudocapsule with lymphocytic aggregation, and locally invaded the surrounding skeletal muscle tissue, and the tumor cells were fusiform to epithelioid with an intensive foamy histiocytic infiltrate. No necrosis or mitosis was observed. Immunophenotyping showed the tumor cells were positive for desmin, either one or both skeletal muscle markers (myogenin or MyoD1), and negative for h-caldesmon, ALK and SMA. The Ki-67 index was<5%. Using next-generation sequencing, one case was found to harbour KRAS (G12D) and MSH3 (Q470*) mutations. Conclusions: HRRMT is a newly described skeletal muscle tumor with uncertain malignant potential. Its diagnosis and differential diagnosis depend on morphologic and IHC staining. No specific molecular genetics changes have been identified so far.

Evaluación de la recurrencia de tumores musculoesqueléticos mediante gammagrafía complementada con SPECT/CT con talio-201 en población pediátrica / Evaluation of recurrence of musculoskeletal tumors with thallium-201 scintigraphy plus SPECT/CT in pediatric population

Resumen Introducción: Los estudios de imagen, como la tomografía simple y contrastada, son la primera aproximación diagnóstica para detectar la recurrencia de tumores musculoesqueléticos. El objetivo de este estudio retrospectivo fue demostrar la utilidad de la gammagrafía acoplada a tomografía computarizada por emisión de fotón único (SPECT/CT) con talio-201(201Tl) en la valoración de tumores musculoesqueléticos malignos con sospecha de recurrencia o enfermedad metastásica. Métodos: Se realizaron 72 estudios gammagráficos y de SPECT/CT para la valoración de la recurrencia locorregional y a distancia, al menos 8 semanas tras la última terapia, en 42 pacientes con diferentes tipos de tumores musculoesqueléticos malignos, como osteosarcoma, sarcoma de Ewing, rabdomiosarcoma, retinoblastoma, sarcoma sinovial y tumor de Wilms en el Hospital Infantil de México. Se calcularon el valor predictivo positivo (VPP) y el intervalo de confianza del gammagrama y de la SPECT/CT en comparación con el resultado del análisis histopatológico y el seguimiento clínico y radiológico para identificar la recurrencia. Resultados: La gammagrafía fue anormal en 30 (71.4%) de los 42 pacientes. Se detectaron 33 lesiones (30 pacientes) por gammagrafía y 25 (21 pacientes) por telerradiografía de tórax y tomografía de dos regiones. La SPECT/CT se realizó en 30 pacientes y se detectaron 12 lesiones adicionales al rastreo planar. El VPP con la gammagrafía fue del 82%, y con la SPECT/CT, del 100%. Conclusión: La gammagrafía con 201Tl puede considerarse un estudio adecuado para identificar los sitios de viabilidad tumoral, con alto grado de certeza diagnóstica al complementar con SPECT/CT.

Abstract Background: Imaging studies, particularly simple and contrast-enhanced tomography, constitute the first diagnostic approach to detect recurrence of musculoskeletal tumors. The aim of the present retrospective study was to demonstrate the usefulness of scintigraphy plus SPECT/CT (single photon emission computed tomography) with thallium-201 (201Tl) in the evaluation of malignant musculoskeletal tumors with suspicion of recurrence or metastatic disease. Methods: Eight weeks after the last therapy, 72 scintigraphy and SPECT/CT studies were performed to assess regional recurrence and metastatic disease in 42 patients with different types of malignant musculoskeletal tumors, such as osteosarcoma, Ewing's sarcoma, rhabdomyosarcoma, retinoblastoma, synovial sarcoma, and Wilms tumor at the Hospital Infantil de México Federico Gómez. The positive predictive value (PPV) and the confidence interval of the scintigraphy and SPECT/CT were calculated when compared with the results of the histopathological analysis and the clinical and radiological follow-up for the identification of recurrence. Results: Scintigraphy was abnormal in 30 (71.4%) of the 42 patients; 33 lesions (30 patients) were detected by scintigraphy and 25 lesions (21 patients) by chest X-ray and tomography of two regions. The SPECT/CT was performed on 30 patients, where 12 lesions were detected in addition to the planar scintigraphy. Scintigraphy showed a PPV of 82%; SPECT/CT, 100%. Conclusion: 201Tl-scintigraphy can be considered as an adequate study to identify the sites of tumor viability with a high degree of diagnostic certainty combined with the SPECT/CT technique.

Lipoma subdeltoídeo como causa de síndrome do impacto no ombro – um relato de caso / Subdeltoid lipoma causing shoulder impingement syndrome – a case report

A síndrome do impacto é definida pela colisão dos tendões dos músculos que formam o manguito rotador contra o arco coracoacromial. Vários fatores concorrem para essa doença e são classificados como estruturais ou funcionais. Os primeiros são alterações do arco coracoacromial, úmero, bursa e manguito rotador; os fatores funcionais estão relacionados com o mecanismo de elevação do membro superior, por meio da atividade sincronizada e equilibrada entre o manguito rotador e os músculos da cintura escapular. Os autores relatam aqui, o caso de um lipoma parosteal do úmero proximal, situado entre os ventres musculares do deltoide, redondo menor e infraespinhal ocasionando os sinais clínicos da síndrome do impacto. Trata-se de uma ocorrência rara, caracterizada como uma causa estrutural para o desencadeamento dessa sintomatologia.

The impingement syndrome is defined by the compression of the rotator cuff tendons against the coracoacromial arch. Several factors contribute to this condition and they are classified as structural or functional factors. The former are changes in the coracoacromial arch, proximal humerus, bursa and rotator cuff, and the latter are related to the mechanism of the upper limb by means of synchronized activity and balanced between the rotator cuff and scapular girdle muscles. The authors report here a case of parosteal lipoma of the proximal humerus, located between the muscles deltoid, teres minor and infraspinatus causing clinical signs of impingement. It is a rare occurrence, characterized as a structural cause for the onset of this symptom.

Soft tissue metastases from differentiated thyroid cancer diagnosed by 18F FDG PET-CT / Metástases em tecidos moles de câncer de tireoide diagnosticadas por 18F FDG PET-CT

Distant metastases of differentiated thyroid cancer are unusual; lung and bones are the most frequently affected sites. Soft tissue metastases (STM) are extremely rare. We describe two cases of patients with differentiated thyroid cancer metastasizing to soft tissues. Both patients had widespread metastatic disease; clinically asymptomatic soft tissue metastases were found by 18-Fluordeoxyglucose positron emission tomography/computed tomography (18F FDG PET-CT), and confirmed by cytological and/or histopathological studies. These findings underscore the ability of 18F FDG PET-CT in accurately assessing the extent of the disease, as well as the utility of the method to evaluate regions of the body that are not routinely explored.

As metástases a distância em carcinoma diferenciado de tireoide são raras. Pulmão e ossos são os lugares mais frequentemente atingidos. As metástases em tecidos moles são extremamente infrequentes. Neste artigo, descrevemos dois casos de pacientes com câncer diferenciado de tireoide com metástases em tecidos moles. Ambos os pacientes padeciam de enfermidade avançada. As metástases em partes moles foram assintomáticas e detectadas mediante 18-Fluordeoxyglucose positron emission tomography/computed tomography (18F FDG PET-CT), sendo confirmadas por citologia e/ou histopatologia. Esses achados ressaltam o valor do 18F FDG PET-CT para a avaliação correta da extensão da enfermidade e a utilidade do método para avaliar regiões do corpo que não são exploradas nos estudos de rotina.

Hibernoma of the neck: a case report

Hibernoma denotes a tumor derived from brown fat. It is an uncommon tumor that has been described only in a few case reports and small series. Although it is usually found in the interscapular region, it has also been reported in sites where brown fat is less common. Only a few cases have been described in the neck region. We report a case of 47 years old man who was admitted with history of a mass in his posterior cervical region. Upon surgical excision, a soft encapsulated mass was found which pathologically was consistent with hibernoma

Benign vs malignant soft tissue neoplasms: Limitations of magnetic resonance imaging.

Aims: Various features have been described in the literature to differentiate benign from malignant lesions. The aim of the present study was to study the accuracy of each of these features and that of magnetic resonance imaging (MRI) in diagnosing malignant lesions. Materials and Methods: Fifty-five consecutive patients presenting with neoplastic (both benign and malignant) lesions diagnosed clinically and on ultrasound were studied and their MRI features were compared with the findings on surgical exploration and histopathologic examination. Results: There were 32 (58%) benign and 23 (42%) malignant masses. Malignant masses were more common in patients older than 20 years (83%), and these had symptoms of less than 6 months duration (75%), as against benign lesions. The swelling was painful in 8 malignant masses and these were more common in the upper limbs (61%). Various features of malignant lesions were size more than 5 cm in 83%, change in signal intensity from homogenous on T1-weighted images to heterogenous on T2-weighted images in 74%, irregular margins in 74%, and heterogenous contrast enhancement in 91%. The accuracy of these features was 76%, 58%, 78%, and 60%, respectively. Most benign and malignant lesions were intramuscular in location. A significant number (38%) of benign lesions were located in the intermuscular facial plane. Definitive diagnosis was made in 42% of the lesions. Conclusions: MRI is an excellent modality for evaluating soft tissue neoplasms; however, prediction of a specific diagnosis and differentiation of malignant and benign lesions is not always possible.

Granular Cell Tumor of The Inferior Rectus Muscle

A 53-year-old woman complaining of vertical diplopia, presented with a localized swelling in the right lower lid. Magnetic resonance imaging studies demonstrated a relatively well-defined mass in the inferior rectus with similar signal characteristics to the muscle. Excisional biopsy of the mass revealed granular cell tumor composed of S-100 positive cells with acidophilic granular cytoplasm and a peripheral lymphocytic infiltration. Granular cell tumor, which is very rare in the orbit, should be considered in the differential diagnosis of tumors adjacent to or within the extraocular muscles, particularly in the inferior orbit.

Single Institutional Experience of Bladder-Preserving Trimodality Treatment for Muscle-Invasive Bladder Cancer

The authors designed this study to determine the clinical effectiveness of trimodality treatment, i.e., transurethral resection of a bladder tumor (TURBT) and concurrent chemoradiotherapy (CRT). Twenty patients with a muscle-invasive bladder cancer were treated by TURBT followed by concurrent cisplatin (75 mg/m(2) day), administered on weeks 1 and 4 of radiotherapy. According to residual tumor status after TURBT, patients were classified into patients with a complete TURBT group and incomplete TURBT group. Response to treatment was evaluated by restaging TURBT at 4 weeks after completing CRT (post-CRT). Fifteen patients (75%) achieved complete remission (CR) at restaging; 10 patients (50%) remained continuously free of tumor recurrence. Disease-specific and overall survivals were 51.1% and 38.6% at 5 yr post-CRT, respectively. Of 16 patients in the complete TURBT group, 14 patients (87.5%) achieved CR, which was significantly different from that observed in the incomplete TURBT group, in which only 1 (25%) of 4 patients achieved CR (p=0.032). Five- year disease-specific and overall survivals were 71.6% and 53.5%, respectively. Ten patients (90.9%) maintained their own bladder among the 11 surviving patients. Trimodality treatment was found to be an effective treatment in patients who underwent complete TURBT for a muscle-invasive bladder cancer.

Chondroid lipoma--a case report.

Chondroid lipoma is a rare fatty tumor of soft tissues, especially in limbs and limb girdles. Though it is clinically benign, the main importance lies in its histological similarity with myxoid liposarcoma and chondrosarcoma, which have poorer prognosis. In our study, classical histological pattern of chondroid lipoma was confirmed on H&E and PAS stains with low mitotic count.

Focal eosinophilic myositis--a rare cause of pseudotumor.

Idiopathic focal eosinophilic myositis is a rare benign pseudotumor of skeletal muscle of unknown cause, characterized by focal eosinophilic infiltration of striated muscle. It can mimic a soft tissue sarcoma clinically and on gross examination of the specimen. Microscopic examination establishes the diagnosis. It is important to recognize this pseudosarcomatous lesion so as to spare the patient from anxiety.

Unsuspected metastatic renal cell carcinoma with initial presentation as solitary soft tissue lesion: a case report.

A 42 year old male presented with painless soft tissue mass 8x7x6.5 cm in right scapular region for 2 months. Fine needle aspiration cytology (FNAC) showed a malignant clear cell tumour. Ultrasonography (USG) abdomen revealed a heterogeneous mass m 8.6x7x8.4 at the lower pole of left kidney. USG guided FNAC from left kidney mass showed cytomorphology consistent with RCC.

Proliferative myositis--a case report.

Proliferative myositis is a recently recognized and unusual reactive fibroproliferative lesion of striated muscle. It shows a bizarre cytological and histological appearance that can mimic a soft tissue sarcoma. It is important to recognize this pseudosarcomatous lesion so as to spare the patient anxiety and unnecessary surgery.

Schwannomatosis presenting as a painful gluteal swelling--a case report.

A 58 years old male came with a painful swelling in right gluteal region. On examination a small mass was found which was subsequently excised. Histopathological study reported presence of presumptive schwannomatosis, as there were 4 tumours composed of Antoni A and Antoni B areas along with Verocay bodies. As post-operative MRI scan of base of brain and ophthalmological examination of patient failed to reveal vestibular schwannomas and ocular stigmata of neurofibromatosis type 2 (NF-2) respectively, a final diagnosis of definite schwannomatosis was made.

Solitary intramuscular nasal Juvenile Xanthogranuloma: a case report with review of literature.

Juvenile Xanthogranuloma is a non-langerhans cell histiocytosis characterized by yellowish cutaneous nodules that usually appear in early infancy and childhood. Intramuscular variant is a rare form, with only eight reported cases, and none reported in ala of nose. Sheets of histiocytes, few touton giant cells and infiltrative borders makes it susceptible to misdiagnosis as childhood sarcomas or lymphoproliferative disorders. Awareness of the lesion aided by immunohistochemistry helps in reaching the proper diagnosis.

Piloleiomyoma--a report of five cases.

Piloleiomyomas are uncommon smooth muscle neoplasms of the skin with a few reproted cases in Indian literature (1,2,3,4,5). They are often misdiagnosed clinically. A correct biopsy report is important because patients may have to be managed medically since surgery is associated with a high rate of recurrence. The classical histologic findings, and Masson's stain to confirm the smooth muscle origin aids in the correct diagnosis.

Cystic hygroma of the gluteal region.

Cystic hygromas occur most commonly in the neck. Rarely are they known to involve the axilla, groin, mediastinum, retroperitoneum, pelvis, mesentery, omentum and spleen. We successfully managed a case of cystic hygroma of gluteal region in a one and half year old child who presented with a cystic, non transilluminant swelling in this region since birth. The diagnosis of cystic hygroma was made by surgery and subsequently confirmed after histopathological examination. Because of rarity of cystic hygroma in gluteal region this case in being reported.

Tenosynovial giant cell tumor of finger, localized type: a case report

The authors report a typical case of tenosynovial giant cell tumor of the right middle finger of a 31-year-old man. Histologically, this tumor is characterized by a discrete proliferation of rounded synovial-like cells accompanied by a variable number of multinucleated giant cells, inflammatory cells, and xanthoma cells. Clinicopathologically, this tumor is a benign lesion that nonetheless possesses a capacity for local recurrence. Local excision with a small cuff of normal tissue is the treatment of choice in this tumor.

Congenital localized multiple fibromatosis: a case report.

Clinical, histopathologic and electronmicroscopic findings in a case of congenital localized multiple fibromatosis of interscapular region are presented. This 10 year-old Japanese girl developed this lesion since she was 3 weeks old, metastases have never been observed. The histological and electron-microscopic features point to the hamartomous origin of this tumor with partial differentiation of its cells towards myofibroblasts and atypical fibroblasts. The differential diagnosis from other soft tissue tumors in infancy and early childhood is discussed.

Case report of intramuscular myxoma with review of literature.

This is a case report of a lady who presented with mass in the abdominal wall, clinically diagnosed as neurofibroma. On histological examination it was proven to be an intramuscular myxoma. Since it is rare it was thought relevant to report this case.