Histioeosinophilic granuloma of the thymus.
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Biomedical subjects
Publications and source records attributed to J F Val-Bernal.
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This report documents a rare variant of mammary hamartoma with presence of lobules of brown adipose tissue. The lesion was discovered in a control mammogram performed in a 42-year-old woman 15 months after hormonal substitute therapy for radical hysterectomy with bilateral salpingo-oophorectomy. Complete excision is the adequate therapy. The presence of brown fat in the hamartoma should be considered in the differential diagnosis of the exceptional hibernoma of the breast and other tumors composed of large cells with granular or multilocular cytoplasm, such as lipoblastoma, sebaceous adenoma, granular cell tumor and histiocytoid or lipid rich carcinomas.
A complete understanding of the biological mechanisms that take part in the hyperacute vascular rejection is necessary to prevent its development. Nitric Oxide (NO) release by the graft could be one of those mechanisms as cytokine induction of NO synthase in reticuloendothelial cells produces NO with cytotoxic activity. We have performed 20 heterotopic pig-to-dog kidney xenotransplantations in order to determine if cytotoxic NO is released during the hyperacute rejection. Nitrites and cGMP levels were determined in plasma samples taken from the graft artery and vein until vessel thromboses. NO synthase activity was measured in pieces from renal artery and renal tissue. The results show that after discordant xenotransplantation, inducible NO synthase is activated in the transplanted organ, indicating that NO can mediate host tissue damage during the hyperacute rejection.
A case of primary malignant myxoid fibrous histiocytoma of the lung presenting as a solitary lung nodule in a 61-year-old man is presented. This tumor arose in a patient with a transitional-cell carcinoma of the urinary bladder and a well differentiated squamous-cell carcinoma of the larynx. The differential diagnosis between a primary lung tumor, versus a solitary metastasis is difficult and was supported by histological features and the lack of epithelial properties proved by immunohistochemistry. Tobacco was the only etiologic factor known in the patient.
In the present report, we describe a cutaneous myofibroma with a monophasic pattern. The patient was a 12-year-old white boy with an asymptomatic yellow nodule on his glans penis for about 2 1/2 months. The nodular pattern of growth is distinctive: nests of plump spindle cells with a tendency toward interstitial hyalinization within the dermis. Confirmation of the myofibroblastic nature of the proliferation was obtained by histochemical and immunohistochemical studies. The tumor cells showed immunoreactivities for vimentin, alpha-smooth-muscle actin, and collagen type IV but did not stain for desmin. To the best of our knowledge, this is the first case of cutaneous myofibroma to occur on the glans penis. This tumor should be included in the differential diagnosis of mesenchymal neoplasms of the penis.
Perianal basal cell carcinoma is a very rare tumor accounting for only 0.2% of the anorectal tumors. It must be distinguished from basaloid carcinoma of the anus, which resembles it histologically but shows a much more aggressive behavior, metastasizes early, and often proves fatal, thus requiring different therapy. Differential diagnosis of both entities by light microscopy may be difficult. Five cases of perianal basal cell carcinoma and five cases of basaloid carcinoma were studied by means of immunohistochemistry and flow cytometry. Some immunohistochemical markers, such as epithelial membrane antigen, carcinoembrionic antigen, and keratins, as well as the lectin Ulex europaeus agglutinin I stained basaloid carcinoma and were negative for basal cell carcinoma. In contrast, the monoclonal antibody Ber-EP4 seems to be a good marker for perianal basal cell carcinoma and useful in differentiating it from basaloid carcinoma of the anus. Basaloid carcinomas are associated with a significantly higher S-phase fraction than are perianal basal cell carcinomas (p < 0.01).
A case of acute gangrenous appendicitis with perforation caused by metastatic small cell carcinoma of the lung in a 65 year old man is reported. The manifestation of appendicitis occurred more than 4 years after the diagnosis of the bronchogenic carcinoma. With longer survival of patients with disseminated tumors it is probable that new manifestations of those malignancies will be discovered. Acute appendicitis due to metastasis from a distant neoplasm should be considered in the differential diagnosis of right lower abdominal pain in the oncology patient.
Extrarenal angiomyolipomas are rare lesions. An angiomyolipoma located on the right ear lobe in a 49-year-old man is reported. Pathologic examination showed a well-circumscribed subcutaneous nodule, 2 cm in diameter. The components of the tumor were confirmed by immunohistochemistry. Reactivity for HMB-45 was negative. A review of the twelve published cases, including the present, reveals that the patients age ranged from 33 to 77 years (mean 53.6), the male/female ratio was 11.1. The tumors were solitary, asymptomatic, noninvasive, located most commonly in acral skin or on the ear. The clinical impression is that of a cyst, a lipoma or a vascular tumor. Signs of tuberous sclerosis were absent in all cases. In contrast to the renal form, the cutaneous angiomyolipoma is a tumor differing in sex predominance, clinical associations, circumscription, solitariness, and HMB-45 immunoreactivity. Distinction from other mesenchymal lesions depends on recognition of traditional histologic criteria.
A new histologic variant of dermatofibroma, only briefly alluded to in dermatological literature is reported. This tumor was located in the back of a 24-year-old man. It was present for about 2 years and had a history of trauma 2 months before excision. The lesion showed similar characteristics to those of conventional dermatofibroma as well as the presence of groups of granular cells identical to those seen in granular cell tumors. It is important to recognize dermatofibroma with granular cells because it may be confused with a variety of benign or malignant soft tissue tumors containing similar granular cells that entail different significance or prognosis. The immunohistochemical study supports a granular cell change in a dermatofibroma instead of a granular cell tumor that has been traumatized, with secondary formation of a dermatofibroma reaction.
Xanthogranulomatous pyelonephritis (XPN) is an uncommon, but not rare, type of bacterial infection of the kidneys. Malignancies originating within the renal pelvis are uncommon. We report a case of XPN associated with a transitional cell carcinoma (TCC) of the renal pelvis in a 70-year-old woman. The pathogenesis of carcinoma of the renal pelvis in the presence of XPN is related to obstruction, chronic inflammation, and mechanical irritation caused by calculi. In the case reported here, obstruction was due to a concomitant TCC of the ureter without the presence of calculi. A review of the twelve published case reports of XPN with TCC of the renal pelvis, including the present case, showed that the frequency of this association is 3.3%, the average age at presentation is 65.3 (range 49-78) years, and that the male:female ratio is 2:1. Moreover, 25% of the patients had TCC of the ureter and 8.3% TCC of the bladder. The combination of XPN, TCC of the renal pelvis, and lithiasis occurred in 33.3% of the cases. XPN must be treated by nephrectomy not only because it is a destructive inflammatory process leading to complete loss of renal function, but also because the kidney may be harboring a malignant tumor.
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In 87 astrocytic gliomas the number of AgNORs/nucleus was retrospectively studied and data correlated with the histological type of the tumors and survival. All patients were treated by the same surgical team and with uniform criteria. Statistically significant differences (p < 0.01) were found in relation with the AgNOR averages among the histological types of tumors. A statistically significant linear correlation (p < 0.05) between the AgNOR values and survival of the patients was also found. Patients with mean AgNOR values higher than 2.23 and lower than 2.9 survived an average of 11.5 +/- 9.1 months vs. a survival in average of 24.4 +/- 34.1 months with mean AgNOR values under 2.23 (p < 0.05). Patients with AgNOR values higher than 2.9 survived, on average, 7.7 +/- 3.9 months. AgNOR counting in astrocytic gliomas is a reproducible, easy, quick method with prognostic value. AgNORs may be successfully applied in routine material to assess the growth potential of astrocytic gliomas.
BACKGROUND: Plexiform schwannoma (PS) is a rare benign tumor of the nerve sheath that can be located either in the deep soft tissues or in the dermis or subcutis. The tumor predominantly affects young adults and occurs most commonly as a slowly growing asymptomatic solitary nodule in the head and neck region, trunk, and upper extremities. METHODS: A cutaneous PS located in the preauricular region of a 19-year-old white female is reported. The patient exhibited six "café-au-lait" spots in the trunk and the extremities. Magnetic resonance imaging examination showed bilateral tumors in both acoustic nerves (considered schwannomas) and also masses in the right major sphenoidal wing, falx, and T2-T3 level of rachis and a solid and cystic tumor in the low medulla oblongata. Tumors of the preauricular region, medulla oblongata, spinal cord at level T2-T3, and major sphenoidal wing area were surgically removed. The tumors were studied by immunohistochemistry and diagnosed as PS, pilocytic astrocytoma, and meningiomas, respectively. RESULTS: Seventy-eight cases of PS have been reported in the literature: 8 (10.2%) have been associated with clinical schwannomatosis, 6 (7.7%) with multiple cutaneous schwannomas syndrome, and only 3 (3.8%) with neurofibromatosis type 1 (NF-1). CONCLUSIONS: In this report, to the authors' knowledge, for the first time PS is described associated with neurofibromatosis type 2. The tumor does not appear to have significant association with NF-1. Plexiform schwannoma should be recognized because it may be misdiagnosed as plexiform neurofibroma or other plexiform malignant tumors. Differentiation from plexiform neurofibroma is important, because the latter is virtually pathognomonic of neurofibromatosis type 1 and has a propensity for malignant transformation.
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A case is reported of an 84-year-old white man in whom a palisaded encapsulated neuroma (PEN) had developed in his glans penis over the course of 50 years. It represents a distinctive cutaneous nerve sheath tumor that consists of an overgrowth of both axons and Schwann cells and is surrounded by a complete or incomplete capsule of perineural cells. This entity warrants wider recognition by urologists and uropathologists. To our knowledge this is the first description of this kind of tumor in the glans penis.
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A 60-year-old woman had extensive and recurrent foreign-body granulomatous inflammation of her forehead. The granulomata contained double refractile crystalline material. Electron probe roentgenographic microanalysis identified silicon, calcium, aluminum, potassium, and sulphur in the crystalline material. Silicon-rich particles are generally considered exogenous. A diagnosis of sarcoidosis was confirmed by the presence of bilateral hilar and mediastinal lymphadenopathy due to biopsy-proven nodal replacement by noninfectious noncaseating granulomata. We conclude that foreign matter may operate as a nidus for the formation of granuloma in sarcoidosis and that the presence of polarizable matter in a sarcoid granuloma does not rule out sarcoidosis.