Myeloid metaplasia presenting as a splenic mass: report of a case with fine-needle aspiration cytology.

Myeloid metaplasia, i.e., the formation of bone marrow elements outside of the medullary cavity, may occur in any patient with anemia, regardless of the etiology of the anemia itself. The spleen is frequently the site of myeloid metaplasia, and it may present with varying degrees of splenomegaly; however, no cases have been reported where this entity presented as an isolated splenic mass. Our case was a 79-yr-old man who presented with anemia and a splenic mass by CT scan and who underwent fine-needle aspiration (FNA) of that mass. The smears revealed megakaryocytes admixed with other hematopoietic elements. No fatty elements were identified in the smears. We conclude that splenic myeloid metaplasia may present as a discrete splenic mass lesion, and may be diagnosed using the FNA technique.

Chronic atrophic rhinitis with fetor (ozena): a histopathologic tretise.

Biopsy material from 50 patients with a known clinical diagnosis of ozena was examined histopathologically. Certain features were invariably seen, including mucosal atrophy, squamous metaplasia, and chronic inflammatory cell infiltrate which suggests a humoral mediated immune process. Histopathologic features allow ozena to be distinguished from chronic non-specific hypertrophic rhinitis, which may have a cell-mediated immune basis underlying its pathogenesis.

Absence of myelin basic protein in granular cell tumors.

Thirty-one granular cell tumors were studied for the presence of myelin basic protein (MBP) using a monoclonal antibody with a characterized specificity and an immunoperoxidase technique. The tumors studied were from all areas of the body, from both sexes, and from nine decades of age. All the tumors stained negatively for MBP. One brief report using a monoclonal antibody had noted positive staining for MBP in granular cell tumors. A more recent study using polyclonal antibodies found negative staining for MBP in Schwann cell neoplasms including granular cell tumors. This study, using an immunohistochemical technique, demonstrated the absence of an MBP marker in granular cell tumors of diverse location despite the fact that granular cell tumors are widely held to be of Schwann cell origin.

Epithelial polyps of the large intestine. A classification based on biologic behavior.

Classifications of colonic polypoid lesions are often based on their pathogenesis. Little attention is paid to the biologic behavior (or predicted behavior, based on experience) of these lesions. Classification based on biologic behavior separates these lesions, regardless of histogenesis, according to possible malignant potential. This helps the clinician to explain the implications of the histopathologic diagnosis to the patient and to understand when aggressive or prophylactic therapy should be pursued.

Erosive mucosal cysts of the temporal bone. A case report with review of the pathogenesis.

An erosive mucosal cyst of the mastoid process is reported. The endodermal lining contained both goblet and nonkeratinizing squamous metaplastic mucosa. Possible causes of cyst formation and its relationship to epidermoid and "motor oil" cysts are discussed.

Extramedullary hematopoiesis within the hypotympanicum presenting as a glomus tympanicum.

We discuss the case of a 22-year-old black woman who presented with a mass in the left hypotympanicum. Both the pre- and postoperative diagnosis of the lesion was a glomus tympanicum. Histopathologic examination revealed the "tumor" to be a nodule of extramedullary hematopoiesis. Many sickled erythrocytes were also noted within the lesion. A multilingual literature search (English, French, German, Spanish, Portuguese, Italian, and Russian) failed to reveal a documented case of extramedullary hematopoiesis in the hypotympanicum. We assume that the patient's hemoglobinopathy was the cause of her unusual focus of extramedullary hematopoiesis.

Modified Arias-Stella reaction in paratubal epithelium.

The Arias-Stella reaction (hyperplastic changes of the endometrial epithelium associated with cellular atypia) may be seen in uterine or extra-uterine pregnancies. I found a modified Arias-Stella reaction in paratubal epithelial cells. The fallopian tube studied was removed because of ruptured ectopic pregnancy. Although this phenomenon has not been previously reported, it is not really remarkable because of the embryological similarity of paratubal and endometrial epithelium.

Renal involvement by histiocytic medullary reticulosis.

The case of a young man who died seven months after the diagnosis of histiocytic medullary reticulosis is reported. Autopsy and laboratory findings were consistent with a diagnosis of uremia. Liver, lymph nodes, spleen, and bone marrow were involved by neoplastic cells. In addition, the kidneys were massively involved by tumor. Previously published autopsy studies of this rare condition failed to demonstrate massive renal involvement.

Collagens in scar carcinoma of the lung.

Immunohistopathologic and biochemical studies of different collagen types extracted from human scar carcinoma of the lungs have been carried out for definition and evaluation of which types of collagen are involved in the scarring mechanism of such tumors. Tumor homogenates treated with 0.5 M acetic acid and followed by limited proteolysis with pepsin and then by fractional salt precipitation, demonstrated that Type I collagen constitutes the major collagenous component in addition to a significant increase in Type V collagen extracted from human scar carcinoma of the lung. However, when normal membranoalveolar peripheral lung tissues were processed under the same experimental conditions, Type III and IV collagens were relatively higher. Immunohistochemical studies were carried out, and the results confirmed the data above. Furthermore, these studies demonstrated a relative localized increase in Type III collagen in the area surrounding the tumor acini, which suggested that these areas are of active and recent scar formation. This supports the current concept of the scar origin as a desmoplastic reaction of the host tissues toward the neoplastic cell growth.

Elective lymph node dissection in stage I melanoma--necessary or not?

The management of patients with malignant melanoma is somewhat controversial. The most important prognostic factor is depth of invasion. Criteria by both Clark and Breslow are of value. Therapy must not be "standardized," but individualized for each patient.

Paget's disease of the anal mucosa in association with carcinoma demonstrating mucoepidermoid features.

A case of Paget's disease of the anal mucosa with an underlying carcinoma demonstrating mucoepidermoid features is reported. The histopathologic characteristics of both extramammary Paget's disease and mucoepidermoid carcinoma are noted. Special histochemical staining procedures were consistent with the diagnosis. The actual histogenesis of extramammary Paget's disease and mucoepidermoid carcinomas are controversial topics that are briefly discussed in this paper.

Pulmonary hyalinizing granuloma.

We describe a recent case of pulmonary hyalinizing granuloma presenting classically in a young black American female. The diagnosis was made by histopathologic examination. The etiology of this entity remains elusive, however, an abnormal response involving the immune system to an undefined agent (or agents) is the most likely explanation.

Herpes simplex encephalitis.

This is an acute necrotizing encephalitis with a high mortality rate. It is thought to occur by the reactivation of herpes simplex virus type 1 from latently infected trigeminal ganglia, with subsequent centripetal spread and fulminant growth in tissue of the central nervous system. Prompt diagnosis and antiviral therapy are required because of the rapidly progressive nature and severe consequences of this disease. The physician must understand the pathophysiology to fully appreciate the need for early diagnosis and the gravity of mismanagement.

Intussusception: a case review.

This study is a review of all cases of intussusception from December 1971 to December 1981 at the Erlanger Medical Center in Chattanooga. Only 24 cases were found. A disproportionate number of patients were white (92%). The male to female ratio was 2 to 1. There was no regular seasonal variation. Several patients were below the third percentile in weight for their ages. The most common signs and symptoms were vomiting, pain, and bleeding per rectum. The occurrence of anatomic lead points was high, and the success rate for hydrostatic reductions was low. The use of glucagon before barium enema increased the success rate of hydrostatic reduction by 75%, from four successful reductions to seven of 20 attempts.