Sclerotic fibroma (storiform collagenoma)-like stroma in a fibroadenoma of axillary accessory breast tissue.

Accessory breast tissue is a subcutaneous remnant persisting after normal embryological development of the breast. It occurs most frequently in the axilla. Fibroadenomas in axillary breast tissue are rare. We report the case of a 29-year-old female patient who presented a fibroadenoma arising in the accessory breast tissue of the right axillary fossa. The neoplasm showed foci of sclerotic fibroma-like stroma. The patient had no signs of Cowden's syndrome. To the best of our knowledge, a lesion of this kind has not been previously reported. This stromal change suggests an uncommon involutional phase of the fibroadenoma with production of sclerotic and hypocellular collagen. The lesion should be differentiated from extraneural perineuroma, from the changes in fibroadenomas in Cowden's syndrome, from sclerosing lobular hyperplasia (fibroadenomatoid mastopathy) and from pseudoangiomatous stromal hyperplasia.

Subgemmal neurogenous plaques of the tongue: a systematic autopsy study.

Subgemmal neurogenous plaque (SNP) is a subepithelial nerve plexus associated with taste buds, occasionally observed in tongue biopsies. There is no evaluation of the prevalence of this structure in the general population. We present a systematic study of samples obtained at random from the dorsal portion of the oral tongue in 205 consecutive complete autopsies. Each sample was about 15 mm long and 10 mm thick. Four hundred fifty-eight samples were routinely obtained and an average of 2.23±0.88 samples per case (range 1-7) was collected. The total number of SNPs observed was 556, with a mean of 2.71±2.68 per case (range 0-16). This means that for every 15 linear mm of the oral tongue, approximately 2.7 SNPs can be present. SNPs display several ages, and they do not show sex differences. The mean size of these structures was 2.1±0.94 mm (range 0.6-3.6 mm). SNP is characterized by its unique neural, zonal pattern with a superficial neurofibroma-like area and a deeper neuroma-like area. Special features of the SNPs include the presence of taste buds (49.1%), ganglion cells (26.3%), dilated thin-walled vessels (11.3%), salivary gland excretory ducts emptying on the surface of the papillae (6.1%), moderate-severe inflammatory infiltrate (6.8%), presence of lymphoid tissue in the vicinity (7.0%), and hyperplasia of the epithelial cover with pseudoepitheliomatous appearance (7.0%). The differential diagnoses include schwannoma, neurofibroma, ganglioneuroma, traumatic neuroma, mucosal neuroma, and squamous cell carcinoma. SNPs are small, normal structures that may undergo hyperplasia and are usually seen incidentally.

Nodular spindle cell proliferation in the wall of a varicose vein mimicking Kaposi's sarcoma.

Exuberant reparative reactions resembling sarcoma have been reported in the genitourinary tract, thyroid, breast, lymph node, oral cavity and skin, but not in a varicose vein. Presented herein is the case of a 55-year-old man who showed an incidental nodular lesion in the wall of a varicose vein on the left leg. The nodule consisted of fascicles of spindled cells with ovoid or elongated nuclei and delicate chromatin that showed diffuse reactivity for CD31, alpha-smooth muscle actin and D2-40. This histopathological appearance, when coupled with extravasated erythrocytes and interstitial hemosiderin deposits, resembled Kaposi's sarcoma or spindle cell angiosarcoma. Key features helpful for recognizing that the proliferation we describe is a form of tissue repair include an association with obvious hemorrhage; lack of well-formed curved fascicles of spindled cells; lack of intracytoplasmic hyaline globules; lack of intracellular vacuolization; cytological blandness; low mitotic count; absence of inmmunoreactivity for human herpesvirus-8 (HHV-8) latent nuclear antigen-1; and absence of HHV-8 in polymerase chain reaction (PCR) analysis.

Hypodermal decidualized endometrioma with aberrant cytokeratin expression. A lesion mimicking malignancy.

Decidualized endometrioma is a pseudoneoplastic lesion that may appear as a solitary nodule in the hypodermis, simulate a malignant epithelioid tumor, and can represent a diagnostic challenge. A 36-year-old woman delivered a full-term baby by cesarean. At the immediate puerperium, she complained of a subcutaneous nodule measuring 2.5 cm, underneath a previous caesarean scar from the former full-term delivery 3 years earlier. Histologic features included a nodular growth pattern of large monomorphic epithelioid cells showing diffuse positivity for cytokeratin (AE1/AE3, 18), human placental lactogen, and CD10 and focal positivity for inhibin alpha. The main differential diagnoses include trophoblastic neoplasia and deciduoid mesothelioma. Good clinicopathological correlation is essential for the correct diagnosis. Immunohistochemical stains can be misleading. An important clue is the combination of large decidualized cells and lumens lined by flat or low cuboidal cells that are atrophic endometrial glands. This lesion has a benign behavior.

Renal oncocytoma with prominent xanthomatous reaction. A rare histopathological variant of oncocytoma.

Renal oncocytoma (RO) is a distinctive neoplasm with a well-recognized gross and cytoarchitectural appearance. However, on some occasions, it may show uncommon, atypical, or worrisome gross and microscopic features potentially generating diagnostic difficulties. We herein review the oncocytoma variant characterized by a significant intraneoplastic xanthomatous reaction that produces a variegated macroscopic appearance. This feature may pose a genuine diagnostic problem with conventional (clear cell) renal cell carcinoma (RCC) because this reaction creates a departure from the typical uniform, tan-brown appearance of oncocytoma. The microscopic presence of foamy macrophages in RO may potentially lead to diagnostic difficulties with tumors exhibiting eosinophilic cells and significant infiltration for lipid-laden foamy macrophages such as cystic RCC, unclassified RCC rich in foamy macrophages, the solid variant of papillary RCC with oncocytic features, post-neuroblastoma RCC, succinate dehydrogenase-deficient RCC, mucinous-poor tubular and spindle cell carcinoma, and the oncocytic variant of the epithelioid angiomyolipoma. In conflictive cases, an immunohistochemical panel should help to solve the diagnostic problem. Therefore, the presence of abundant foamy macrophages should not dissuade the pathologist from establishing a diagnosis of RO. Prominent xanthomatous reaction despite its low frequency (4.3%) can be considered an additional feature of RO. Thus, RO should be added to the list of renal tumors that can show a significant reaction of lipid-laden foamy macrophages. Besides, Gamna-Gandy bodies can be present in this tumor.

The nipple-areola complex epidermis: a prospective systematic study in adult autopsies.

The prevalence of different types of clear cells and of the mite Demodex in the nipple-areola complex of adult autopsies of both sexes not suffering from breast cancer was studied in a total of 140 nipples. The epidermis of the nipple-areola complex shows squamous cells and 3 types of clear cells: Toker cells, pagetoid dyskeratosis cells, and signet ring-like cells. Toker cells were identified by standard light microscopy in 13 of 140 nipples (9.3%). Reactivity of these cells for CK7 was observed in 35 nipples (25%). They are derived from the lactiferous duct epithelium. Pagetoid dyskeratosis cells were identified in 56 of 140 nipples (40%). In 12 nipples, these cells were conspicuous (8.6%). It is suggested that the proliferation of these cells is induced by friction. Signet ring-like cells were identified in 71 nipples (50.7%). In 2 nipples, these cells were conspicuous (1.4%). They are a consequence of artefact related to formalin fixation. The prevalence of all these clear cells has no relationship with gender. Routine histopathological examination is usually enough to distinguish the characteristic features of the clear cells involving the nipple epidermis and permits differentiation of other entities with epidermal pale cells. Demodex mites were observed in 58 nipple-areola complexes (41.4%). They were more common in male nipple-areola complexes (P < 0.05). The prevalence of these mites was seen to remain steady along the years since the third decade. Demodex mites are common parasites of human nipple and are apparently of no pathologic significance.

Postoperative spindle cell nodule of the breast: Pseudosarcomatous myofibroblastic proliferation following endo-surgery.

Despite the frequent use of fine-needle aspiration, core biopsy and surgery, postoperative spindle cell nodule (PSCN) is a rare pathological complication that may be diagnostically treacherous. Presented herein is the case of a 52-year-old woman who developed a 7 mm mammary nodular lesion 66 days after removal of an area of columnar cell hyperplasia involving cellular and architectural atypia, performed with the Mammotome Breast Biopsy System. The lesion was highly cellular and composed of intersecting fascicles of plump spindle cells with blunt-ended elongated nuclei and nucleoli easily visible. Interspersed mononuclear cells and hemosiderin-laden macrophages were evident. PSCN is a reactive, benign myofibroblastic proliferation. Differential diagnosis includes benign and malignant spindle cell lesions of the breast. Recognition of this reactive lesion will avoid overdiagnosis of spindle cell malignant tumor. Attention to clinicopathological and histological features should result in accurate recognition of this lesion.

Cardiac intracavitary metastasis of a malignant solitary fibrous tumor: case report and review of the literature on sarcomas with left intracavitary extension.

BACKGROUND: Solitary fibrous tumor (SFT) of the pleura with malignant progression occurs uncommonly. Cardiac intracavitary extension of tumors is rarely seen, with left side location being exceptional. METHODS AND RESULTS: The authors report the first case of a malignant SFT metastatic to the heart occurring in a 74-year-old woman. The tumor first presented as a slow-growing pleural SFT that in 6 years reached a size of 16 cm. Two months after a complete surgical resection, the tumor was found to spread to the left atrium by intracavitary extension from the left upper pulmonary vein, simulating a cardiac myxoma. The primary tumor showed established features of malignancy including size greater than 10 cm; gross findings of necrosis; high cellularity, cytological atypia, and eight mitoses per 10 high-power fields. Immunohistochemical study revealed positivity of the tumor cells for CD34, bcl-2, and CD99. Aside from the present report, 52 previous cases of sarcoma with intracavitary extension to the left side of the heart have been described. Bone sarcoma is the type most frequently found. Peripheral arterial embolism can be a complication of advanced mesenchymal malignancy in 21% (11/53) of reported cases. CONCLUSION: Accurate histopathologic recognition of this rare type of metastatic disease is important because of the adverse prognosis as compared to cardiac myxoma.

Low-grade serous primary peritoneal carcinoma incidentally found in a hernia sac.

Very rarely, a primary peritoneal serous carcinoma can be observed in a hernia sac. We herein describe a low-grade serous primary peritoneal carcinoma incidentally found in a postmenopausal woman following examination of the femoral hernia repair sac. Our case is significant for its unusual presentation. The lesion initially appeared as a 0.3-cm tumor that disseminated in the peritoneum, persisted, and progressed for 75 months. The absence of ovarian disease indicated a primary peritoneal origin. Tumor cells were immunohistochemically positive for PAX8, claudin-4, and VE1, excluding the possibility of being of mesothelial origin. Recognition that a low-grade serous primary peritoneal carcinoma can be incidentally found in a hernia sac should simplify future diagnoses. Immunohistochemistry is helpful in making the correct diagnosis.

Well-differentiated papillary mesothelioma manifesting in a hernia sac.

Well-differentiated papillary mesothelioma (WDPM) is a tumor of uncertain malignant potential that usually occurs as a multifocal lesion of the female peritoneum, and is incidentally found at the time of surgery. We present here a multifocal case that had arisen from the lining of a hernia sac. To our knowledge, only four cases of this event have been previously described. A review of the five cases reported, including our case, revealed that the mean age of the patients was 56.6±8.35 years. There was predominance in men (4:1). In four cases, the lesion was incidental. Most tumors were found in inguinal hernias. Four cases presented with gross abnormalities in the hernia sac. All the five patients were alive with no evidence of WDPM after a mean follow-up of 38.6 months. Extensive sampling of this rare lesion helps to rule out an epithelial malignant mesothelioma and prevents overtreatment.

Cardiac papillary fibroelastoma: retrospective clinicopathologic study of 17 tumors with resection at a single institution and literature review.

Cardiac papillary fibroelastomas (PFEs), which are mainly found in the valves, are rare benign tumors that can cause embolism. Single-center surgical experience in the treatment of this tumor is uncommon. All patients surgically treated for this neoplasm at our institution from January 1995 to October 2012 (15 patients with 17 lesions) were queried for clinical and pathologic characteristics, and the literature was reviewed. The mean age of detection was 55.8±11.48 years. Twenty percent of the patients were male. The tumor was an incidental finding in 60%. Symptoms directly related to PFEs occurred in 40% of patients. The most common clinical presentation in symptomatic cases was embolism (40%), mostly transient ischemic attack or stroke. Cardiac valves were predominantly involved (76.5%); the most commonly valve affected was the aortic valve (29.4%), followed by the mitral valve (17.6%). Concurrent valvular disease was observed in 41.7% of patients. The mean size of tumors was 11.4±7.9mm (range 2-25mm). In 86.7% of the patients, the tumor was solitary. The mitral valve was the most common origin of tumor systemic embolism. Fronds core could be the end stage of hypermature elastic fibers, which grows in apposition to young fibers. Simple surgical excision or valvular reconstruction was accomplished in most patients (58.3%). PFE is usually small, appears singly, and can cause potentially serious complications. Symptomatic and left side tumors should undergo surgical excision with valve-spare surgery when possible. Surgical removal of PFE is safe, efficacious, and definitive.

Pilonidal sinus associated with cellular blue nevus. A previously unrecognized association.

A neoplasm associated with a pilonidal sinus (PS) is a rare occurrence in the course of a common disease. Early detection is imperative. To our knowledge, pilonidal disease associated with a cellular blue nevus (CBN) has not been reported. There is a 10% diagnostic error rate with this last lesion. Here we report the case of a 19-year-old man with recurrent sacrococcygeal PS infection associated with an indurated dome-shaped blue-black nodule 1.7 cm in diameter. Clinical diagnosis of the nodule was uncertain suggesting a pigmentary or a vascular tumor. A complete resection of the two lesions was achieved. Pathological study showed a CBN showing a predominantly alveolar pattern associated with a chronic pilonidal disease. The tumor cells showed diffuse strong reactivity for melan-A and HMB-45, and focal reactivity for S-100 protein. Staining for Ki-67 (MIB1) was virtually negative. Differential diagnoses included atypical CBN, borderline melanocytic tumor and malignant melanoma. Radical excision provides a good prognosis for the rare association consisting of a common disease such as PS with the uncommon CBN.