Primary schwannoma of the thyroid gland: analysis of case characteristics and review of the literature.

BACKGROUND: To improve the characteristics of primary thyroid schwannomas (PTS) and to provide reference basis for clinical diagnosis and treatment. METHODS: PubMed was searched for case reports of PTS up to December 2022 using the search terms "Thyroid nerve sheath tumor" or "Thyroid schwannoma" or "Thyroid Neurilemmoma", respectively. 34 cases were screened. RESULTS: PTS can occur at any age, nodules averaged 3.9 cm. The most common symptoms were voice change and dysphagia. Fine needle aspiration cytology showing spindle-shaped cells should be considered for schwannoma. Most cases underwent thyroid lobectomy or nodule removal with a good prognosis. Tissue types with both Antoni A and Antoni B features are common. Positive immunohistochemical staining for S-100 protein, CD34 and waveform proteins helped confirm the diagnosis. CONCLUSIONS: Positive immunohistochemistry for S-100 and wave proteins helps confirm the diagnosis. Preoperative diagnosis is challenging, but pathology and immunohistochemical staining are the gold standard for diagnosis. The first choice of treatment is surgical resection of the nodules, the prognosis is good.

Mentalis nerve branches supplying the lower lip revisited: a study of human fetuses and donated elderly cadavers.

PURPOSE: Little information is known about the mentalis nerve course from the lower lip approximation margin (free margin) to the upper lip. Likewise, no difference in nerve distribution has been observed between the cutaneous and mucosal parts of the lip. Therefore, this study reexamined mentalis nerve morphology. METHODS: For macroscopic observations, three fresh cadavers were dissected (one male and two females; aged 78-93). We also evaluated histological sections obtained from five donated elderly cadavers (two males and three females, aged 82-96 years) and 15 human fetuses (11-40 weeks or crown-rump length 80-372 mm). Immunohistochemical analysis for S100 protein and tyrosine hydroxylase was performed. RESULTS: In both fetuses and adult cadavers, one to three nerve branches ran upward in the submucosal tissue from the mental foramen. Near the free margin of the lip, some branches passed through the orbicularis oris muscle layer toward the lip skin, whereas others followed a reversed J-shaped course along the free margin. Nerve twigs ran in parallel beneath the mucosa, whereas wavy nerve twigs attached to the basal lamina of the lip epidermis. The difference in nerve endings abruptly occurred at the skin-mucosal junction. Tyrosine hydroxylase-positive sympathetic nerve twigs surrounded arteries and formed a branch composed of S100-negative unmyelinated fibers. CONCLUSION: The lower lip skin was innervated by a perforating branch passing through the orbicularis oris muscle, that was different from the lip mucosa. A sudden change in the nerve ending configuration at the mucocutaneous junction seemed to develop postnatally.

Ossifying fibromyxoid tumor: A rare case report with review of literature and its differential diagnosis.

ABSTRACT: Ossifying fibromyxoid tumor (OFMT) is a rare mesenchymal tumor of uncertain histogenesis with intermediate malignant potential presenting commonly in the fifth to sixth decade in the proximal limb and limb girdle. A 65-year-old male patient presented with a slow-growing gluteal mass. Wide local excision performed showed a well-defined tumor in the subcutaneous plane with a partially hard outer shell. Microscopy showed a moderately cellular tumor having cords and nests of round to ovoid cells with moderate cytoplasm and bland nuclei embedded in a myxo-hyaline matrix. An incomplete peripheral rim of ossification was seen. Pleomorphism/high cellularity was not seen. Mitosis was <2/50 high-power field. On immunohistochemistry, both S100 and desmin were positive. A diagnosis of typical OFMT was rendered. Even though rare with many morphological mimics, OFMT should be diagnosed with precision as most of these tumors are low-grade tumors that require only wide local excision and close follow-up without any adjuvant therapy.

Granular cell tumour of the breast.

Granular cell tumours (GCT) of the breast have similar clinical and radiological features to breast carcinomas. We present a case of a female patient with a tender, palpable lump, and associated skin changes. Imaging of the lesion was suspicious of malignancy. Initial histological examination showed uniform sheets of polygonal cells with abundant granular cytoplasm, and follow-up immunohistochemistry showed strongly positive staining of tumour cells with S100 and CD68, confirming the diagnosis of GCT. Wide local excision with complete resection margins was performed as a curative treatment for this lesion. This case report highlights the importance of considering GCTs in the differential diagnoses of breast lesions suspicious of malignancy and emphasises the necessity of accurate diagnosis of GCT for proper treatment.

Rosai Dorfman Disease with malignant transformation to Histiocytic Sarcoma: A diagnostic conundrum.

ABSTRACT: Histiocytic disorders mostly occur as de-novo nodal or extranodal benign masses with rare secondary malignant transformation. A 10-year-old female presented with 10-cm cervical swelling since 9 months associated with fever. Computed tomography revealed left cervical lymphadenopathy and bilateral lung nodules. Lymph node excision biopsy showed effacement of architecture by atypical histiocytes with marked nuclear pleomorphism and frequent mitosis. Focal areas showed mature histiocytes with emperipolesis. The cells were immunopositive for CD68, CD163, and S100 (focal), whereas they were negative for Langerin and CD1a. The Ki67 proliferative index was 30%. A diagnosis of histiocytic sarcoma in a background of Rosai-Dorfman disease was made.

Tumor neuroectodérmico maligno del tracto gastrointestinal: a propósito de un caso / Malignant neuroectodermal tumor of the gastrointestinal tract: case report

El tumor neuroectodérmico maligno del tracto gastrointestinal es una neoplasia rara con pocos casos reportados en la literatura, especialmente en América Latina. Descrito por primera vez en 2003, se trata de una entidad sin tratamiento estandarizado y de pobre pronóstico. Se presenta el caso de una paciente de 22 años de edad que acude a la consulta por dolor abdominal, anemia y masa abdominal palpable. Luego de estudios pertinentes se decide la conducta resectiva y el posterior tratamiento oncológico. (AU)

Malignant gastrointestinal neuroectodermal tumor (GNET), formerly known as clear cell sarcoma of the gastrointestinal tract, is an extremely rare tumor of mesenchymal origin, which presents great microscopic and molecular similarity to clear cell sarcoma found in other parts of the body, such as tendons and aponeurosis. It is characterized by its rapid evolution, high recurrence rate and frequent diagnosis as metastatic disease.1,2 (AU)

Schwannoma intratorácico / Intrathoracic schwannoma

El schwannoma (neurilemoma) es un tumor benigno de lento crecimiento originado en la vaina de Schwann, cuya localización en la cavidad torácica es excepcional. En general es asintomático y se descubre en forma incidental, aunque puede ocasionar síntomas cuando la lesión crece o invade estructuras subyacentes. Su importancia radica en la posibilidad de confusión con tumores malignos. Presentamos una paciente con dolor torácico de evolución prolongada causado por un schwannoma. La imagen tomográfica es sugestiva de tumor extrapulmonar, por ello el schwannoma en esta localización debe ser considerado en el diagnóstico diferencial de tumores pleurales metastásicos o primarios como el lipoma, el tumor fibroso solitario y el mesotelioma.

The schwannoma (neurilemmoma) is a slow-growing benign tumor originating from Schwann sheath whose location in the chest cavity is exceptional. It is generally asymptomatic and is discovered incidentally but can cause symptoms when the lesion grows or invade underlying structures. Its importance lies in the possibility of confusion with malignant tumors. We present a patient who complains of chest pain caused by a prolonged course schwannoma. The tomographic image is suggestive of extrapulmonary tumor, so the schwannoma in this location should be considered in the differential diagnosis of metastatic or primary pleural tumors such as lipoma, solitary fibrous tumor and mesothelioma.

Schwannoma em pálpebra superior esquerda em criança de 10 anos / Schwannoma of the left superior eyelid in a 10-year-old child

Schwannoma é um tumor neurogênico benigno raro, originário das células de Schwann da bainha de mielina dos nervos periféricos. Sua localização nos tecidos oculares não é comum, sendo a órbita o local afetado com maior frequência e o acometimento das pálpebras é muito raro. Há poucos relatos descritos na literatura sobre Schwannoma palpebral, apenas dois em crianças. Este é, em nosso conhecimento, o primeiro caso relatado no Brasil.

Schwannoma is a rare benign neurogenic tumor. It arises from Schwann cells located at the myelin sheath of peripheral nerves. Its incidence is frequently associated with the orbit. Ocular tissues in general and eyelids in particular are rarely affected. Very few reports can be found in the literature describing eyelid schwannomas. Amongst these, we have found only two describing it affecting children. To our knowledge, this is the first case report about eyelid schwanomma in Brazil - and it involves a child.

Langerhans cell histiocytosis

The authors present a rare case of Langerhans cell histiocytosis in a 31 year old female patient with vulvar, peri-anal and oral lesions, diabetes insipidus, pulmonary skin and bone infiltrations. Skin biopsy immunohistochemistry presented positive S100 protein and vimentine, but the diagnosis was done with the demonstration of Birbeck granules with eletronic mucroscopy. The treatment was based on systemical chemotherapy although vulvar lesion has a bad response to chemotherapy.

Sistema histiocítico- macrofágico, suas neoplasias e marcadores / Histiocyte-macrophage system, its neoplasm and tracers

O sistema histiocític-macrofágico é composto por células derivadas da célula primitiva da medula óssea, que se transforma em promonócitos e em monócitos. Nos tecidos, os histiócitos recebem nomes diferentes, como células de Kupffer, células de Langerhans da epiderme, macrófagos alveolares, células do sistema retículo-endotelial, osteoclastos, microglia, células epitelióides e células gigante multinucleadas. Estudos recentes, entretanto, têm demonstrado a heterogeneidade desse sistema, de acordo com a presença de fenótipos imunológicos diferentes. Os histiócitos de zonas T distribuem-se nos órgäos linfóides periféricos em regiöes de células T e compreendem as células de Langerhans da epiderme e células reticulares interdigitantes do linfonodos, baço e medula tímica. Estas células apresentam imunoexpressäo da proteína S-100 por técnicas imuno-histoquímicas. As neoplasias derivadas destas células compreendem as histiocitoses (granuloma eosinófilo, doença de Letterer-Siwe e doença de Hand-Schüller-Christian), assim como a reticulose histiocítica medular, linfo-histiocitose familial e histiocitose maciça sinusoidal. Os monócitos e macrófagos teciduais apresentam imunofenótipos diversos, com demonstraçäo de lisozima, alfa-1-antitripsina e alfa-1-antiquimotripsina por técnicas imuno-histoquímicas. A proteína S-100 é consistentemente negativa nestas células, assim como em neoplasias delas derivadas, correspondendo ao histiocitoma, à histocitose maligna e ao linfoma histiocítico verdadeiro, assim como ao fibro-histiocitoma. A pesquisa imuno-histoquímica de antígenos do sistema histiocític-macrofágico tem-se mostrado de grande valia na identificaçäo e na diferenciaçäo neoplasias deste sistema. As enzimas resistem à fixaçäo e ao processamento do tecido, permitindo estudos retrospectivos e prospectivos de material processado rotineiramente