Solitary epithelioid histiocytoma (reticulohistiocytoma) of the glans penis.

Solitary epithelioid histiocytoma (previously called reticulohistiocytoma) is a rare benign dermal histiocytic proliferation characterized by the presence of large, eosinophilic histiocytes with 'glassy' cytoplasm. This entity assumes importance because of its close histologic resemblance to several benign as well as malignant cutaneous lesions. Involvement of the penis is extremely rare, and to our knowledge, only one case has been previously described in the literature. We report a case of solitary epithelioid histiocytoma in a 34-year-old man who presented with a nodule in the glans penis. Microscopy showed proliferation of large epithelioid histiocytes with abundant eosinophilic cytoplasm, which expressed CD68, CD163 and vimentin. This case highlights the significance of recognizing this unusual lesion and differentiating it from its histologic mimics.

Mixed adenocarcinoma-carcinoid (collision tumor) of the appendix.

OBJECTIVE: To report a case of mixed adenocarcinoma and carcinoid in the gastrointestinal tract. CLINICAL PRESENTATION AND INTERVENTION: A 52-year-old man presented with a mass at the base of the appendix. On microscopic examination of the tumor, mixed adenocarcinoma and carcinoid was identified. The carcinoid component was insular/trabecular in morphology, and the epithelial component revealed mucinous adenocarcinoma. Morphologically and immunohistochemically the 2 components showed a clear-cut distinction, without any intervening intermediate cell population. The adenocarcinomatous component displayed omental deposit and metastasis to the regional lymph nodes. One year later, the patient developed multiple metastatic deposits of adenocarcinoma in the liver, rectus muscle, ileum and sigmoid colon. CONCLUSION: This tumor had an aggressive clinical course and behaved more like adenocarcinoma than carcinoid.

Acute amebic appendicitis: report of a rare case.

Acute appendicitis of amebic origin is considered a rare cause of acute appendicitis. We report a case of amebic appendicitis presenting with fever, severe pain in the right lower quadrant of the abdomen and rebound tenderness. Lab investigations revealed neutrophilic leukocytosis. The patient underwent appendectomy. Histopathological examination revealed numerous Entameba histolytica trophozoites in the mucosa of the appendix. Acute appendicitis of amebic origin does not appear frequently. Appendicular amebiasis can give the clinical features of acute appendicitis and should be treated accordingly.

Foreign body reaction to soft tissue filler simulating atypical lipomatous tumor: report of a case.

Injectable silicone or microimplant has been extensively used for the soft tissue augmentation. Here we report a case of cystic granulomatous reaction to injectable tissue filler, possibly liquid silicone, used for tissue augmentation in the buttocks. Patient presented with a progressive painful swelling in the lower back over L4-L5 and S1 lumbosacral region of 4-month duration. The lump was excised and microscopic examination revealed multiple cystic spaces of variable size lined by foreign body giant cells and macrophages. There were proliferating spindle cells admixed with many multivacuolated mononuclear cells simulating lipoblasts. These morphologic features were highly reminiscent of atypical lipomatous tumor. To our knowledge, this is the second recorded case from the Middle East of such an unusual foreign body reaction. The dermatologists and pathologists should be aware of this unusual lesion. Although rare, this reaction can have important esthetic implication and the patient should be informed about their risk.

Jejunal perforation caused by schistosomiasis.

We report an extremely unusual case of jejunal perforation caused by adult schistosoma worm in a 49-year-old South Korean man who presented with acute abdomen. To our knowledge, this is the first case of jejunal perforation associated with adult worm of schistosoma.

An unusual case of extensive epididymotesticular malakoplakia in a diabetic patient.

A 67-year-old Saudi man with poorly controlled diabetes-mellitus underwent orchiectomy for a painful left testicular swelling that did not respond to antibiotics. Clinical diagnosis was testicular malignancy. Histologic workup demonstrated extensive involvement of the testis and epididymis by diffuse infiltrate of large histiocytes with eosinophilic granular cytoplasm and numerous Michaelis-Gutmann bodies, which were diagnostic of malakoplakia. Very rarely, malakoplakia has been described in association with diabetes mellitus. Such an extensive malakoplakia occurring at an unusual site in association with systemic illness lends support to the view that a compromised immune status could be etiologically important in malakoplakia. We present this case to highlight the importance of diagnosing malakoplakia when it occurs at unusual locations. We also explore the role of diabetes mellitus in the pathogenesis of malakoplakia and compare the relationship between malakoplakia and xanthogranulomatous inflammation, which are closely related to each-other on both clinical and morphologic grounds.

Paraganglioma of cauda equina: report of seven cases.

The authors report seven uncommon cases of paraganglioma of the cauda equina region with reference to their clinical, radiological, and pathological findings. The common presenting symptoms in all the patients were low backache with radiation to both thighs, sensory and motor deficits in four patients, and urinary retention in three patients. One patient presented with ataxia and superficial sidrosis of the brain. Magnetic resonance imaging (MRI) revealed well-circumscribed lesions that were isointense on T1- and T2-weighted images with flow voids. All the tumors were well circumscribed and could be excised completely; however, one recurred. Histological examination revealed a classic "zellballen" pattern in four tumors. Two mimicked ependymoma but were confirmed as paraganglioma by immunohistochemistry. MIB-1 LI was low in all the tumors. Thus, there were no identifying clinical or radiological features that helped in differentiating paraganglioma from other common tumors, such as ependymoma or neurinoma, in this region, and preoperative diagnosis was not possible in any of the cases. Morphologic features and immunohistochemical analysis proved to be the mainstay of arriving at a correct diagnosis. This report highlights the significance of important morphologic features and immunohistochemistry in the diagnosis of paraganglioma at this unusual site.