Accuracy and interobserver agreement of retroareolar frozen sections in nipple-sparing mastectomies.

In the last decades, surgical treatment of breast cancer has enormously changed. As a result, nipple-sparing mastectomy (NSM) has evolved as an oncologically safe and cosmetic approach. NSM includes a subareolar frozen section to evaluate malignancy. We determined the accuracy of subareolar frozen section diagnosis, analyzed the discrepancy factor, and estimated the interobserver agreement of frozen section in NSM. A retrospective review of all NSMs at our institution from 2009 to 2015 was performed. Frozen sections were compared to the final diagnoses to analyze the accuracy of subareolar frozen sections. Discordant results were rigorously evaluated to identify discrepancy factors. Some cases were randomly chosen to assess the interobserver agreement (kappa) among pathologists. The agreement results were evaluated with and without knowledge of the tumor morphology. Among 34 NSMs, the frozen section false-negative and false-positive rate was 5.9% and 8.8%, respectively. The sensitivity and specificity was 77.8% and 88.0%, respectively. Sampling errors and diathermy artifacts explained our false-negative diagnoses. Freezing artifacts and an intraductal papilloma explained our false-positive diagnoses. The interobserver agreement between breast and general pathologists was 0.87 (p<0.0001) and 0.31 (p=0.0001), respectively. The interobserver agreement increased to 0.35 (p<0.0001) in general pathologists with knowledge of the tumor morphology. Subareolar frozen section showed to be a specific test with moderate sensitivity. Papillary lesions can mimic atypical cells and influence the frozen section interpretation. Frozen section in NSM had a better performance in breast pathologists (almost perfect) versus general pathologists (fair). Interobserver agreement may improve with knowledge of tumor morphology.

Carcinoma of the rete testis: A rare testicular tumor.

Carcinoma of the rete testis is a rare malignant tumor which frequently occurs in middle-aged to older patients and has an aggressive biological behavior. We present the case of a 57-year-old man who presented with an ill-defined mass in the right testicle. The patient underwent a radical orchidectomy. Microscopic evaluation showed a neoplasm displaying a complex papillary-cystic architecture, infiltrating the testicular parenchyma. An in situ proliferation of neoplastic cells, with nuclear stratification and scanty cytoplasm was seen at the periphery, within the channels of the rete testis. The tumor infiltrated the tunica albuginea focally without disrupting it completely. Immunohistochemistry was positive for AE1/AE3, CK7, CK34ßE12, D2-40, and PAX8. Imaging studies presented no evidence of metastatic disease. These findings are those of a primary rete testis carcinoma. The transition between benign and neoplastic rete testis epithelium served as a helpful diagnostic clue. Metastatic carcinomas from other sites were considered in the differential diagnosis.

Esophageal tuberculosis in an HIV-positive patient mimicking a spindle cell tumor.

Tuberculosis (TB) of the esophagus is an extremely rare condition, even in immunocompromised patients. We report the case of a 24-year-old man with a past history of HIV and pulmonary tuberculosis who presented with dysphagia and a 2cm submucosal mass in the proximal esophagus. The biopsy was diagnosed as a spindle cell neoplasm in another center. Sections displayed a submucosal lesion formed by spindle and epithelioid cells, surrounded by chronic inflammation. The spindle cells were positive for S100 and CD68, but negative for cytokeratin, desmin, smooth muscle actin, ALK, CD34 and CD117. Ziehl-Neelsen stain was performed and showed many intracellular acid-fast bacilli, confirming the diagnosis of esophageal TB. This case is a reminder that esophageal TB may become manifest as a submucosal lesion and the histiocytic-granulomatous reaction may mimic a spindle cell tumor.

Epithelioid hemangioendothelioma of the parotid gland: A case report in an unusual location with a review of the literature.

Epithelioid hemangioendothelioma (EHE) is a malignant vascular tumor that usually affects the liver, lung, bone and deep soft tissues of the extremities or trunk. To our knowledge, only 3 cases in the parotid gland have been reported to date. We report a case of a 62-year-old woman who presented with a 1-year history of a slow-growing, painless mass over the left mandibular angle. Imaging studies showed a 2cm mass over the left parotid gland with peripheral calcifications. The patient underwent a superficial parotidectomy. Sections displayed neoplastic epithelioid cells with cytoplasmic vacuoles containing erythrocytes, surrounded by a myxohyaline stroma. Immunohistochemistry was positive for CD31, CD34, ERG, and factor VIII, but negative for cytokeratin AE1/AE3, CK7, EMA, SMA, and S100. The findings were those of an EHE involving the parotid gland. This case demonstrates an EHE in a rare location and emphasizes the need to consider this tumor when diagnosing uncommon soft tissue tumors of salivary glands.

Esophageal Pyogenic Granuloma: A Case Report and Review of the Literature.

Pyogenic granuloma (PG) is a capillary hemangioma mainly found in the skin and oral mucosa, but rarely described in the esophagus. We report the case of a 66-year-old man who consulted for retrosternal pain. Endoscopic studies showed a 28-mm polypoid mass located at the distal esophageal mucosa. The patient underwent endoscopic resection, and the histopathological examination showed a neoplastic proliferation of small blood vessels growing in a lobular architecture, with edematous stroma and prominent inflammatory infiltrate. Special stains for fungus showed pseudohyphae compatible with Candida spp. Findings were consistent with those of an esophageal PG associated with Candida infection. This case is a reminder that PG can be found in the esophagus, can be associated with other entities such as Candida infection, and is one of the differential diagnoses of neoplastic vascular proliferations that may mimic malignancy. In addition, we reviewed previously reported cases of esophageal PG.

Malignant Solitary Fibrous Tumor of the Humerus: A Case Report of an Extremely Rare Primary Bone Tumor.

Solitary fibrous tumor (SFT) is a spindle-shaped cell neoplasm originally described in the pleura, but subsequently found in many anatomic sites. Only few cases of primary SFTs in the bone have been previously described in the literature. We present the case of an 86-year-old man with a 1-week history of pain in his left arm. Imaging studies demonstrated a well-defined osteolytic lesion in the proximal humerus measuring 6.1 cm in diameter. Sections showed a round to spindle-shaped cell neoplasm with prominent mitotic activity (28 mitoses per 10 high-power fields) and areas of necrosis, focally surrounding staghorn-shaped vessels. The tumor cells were positive for CD34, CD99, Bcl-2, and STAT6 and negative for smooth muscle actin, epithelial membrane antigen, and cytokeratin AE1/AE3. These findings were consistent with a malignant SFT involving the left humerus. Although extremely rare, SFT should be considered in the differential diagnosis of primary bone tumors. This is the first case report of a primary SFT in a long bone with malignant histological features.

Intraperitoneal Granulomas Unexpectedly Found during a Cesarean Delivery: A Late Complication of Dropped Gallstones.

Laparoscopic cholecystectomy is the treatment of choice for patients with symptomatic cholelithiasis. Spillage of gallstones into the abdominal cavity during laparoscopic cholecystectomy occurs in approximately one-third of cases. Although retained gallstones remain asymptomatic, few cases may develop complications. We report the case of a 29-year-old nulliparous woman presenting with several hard nodules in the omentum, raising the possibility of a metastatic disease. Histological examination demonstrated a bile-stained material and a foreign body-type granulomatous response without neoplastic tissue. Our case demonstrates an example of a complication resulting two years after a laparoscopic cholecystectomy that was unexpectedly found during a cesarean delivery. Pathologists should be aware of this entity to avoid interpretation errors.

Endometriosis mimicking glandular atypia in a cervical cytology.

Endometriosis involving the uterine cervix is a rare condition that can lead to diagnostic errors in the interpretation of Pap smear. We report the case of a 41-year-old patient in whom the initial Pap smear revealed three-dimensional clusters of glandular cells with elongated nuclei, occasional mitosis, and atypia, which was interpreted as atypical glandular cells, not otherwise specified (NOS). The patient was taken to colposcopy and endocervical biopsy. Colposcopy was normal and the biopsy presented glands with elongated nuclei and surrounded by endometrial stroma admixed with normal endocervical glands. Immunohistochemical studies were reactive for CD10 in the stromal cells and vimentin in endometrioid glands. The findings were consistent with cervical endometriosis. Endometriosis in the cervix is an uncommon pathology that mimics malignancy and may be interpreted as atypical or glandular neoplasia in the cytology.