Quantifying change in distributions: a new departure index that detects, measures and describes change in distributions from population structures, size-classes and other ordered data.

Many statistics are available to compare distributions. Some are limited to nominal data while others, such as skew, Kullback-Leibler, Kolmogorov-Smirnov and the Gini coefficient, are useful for providing information about ordered distributions. While many of these tests are useful for determining properties of data in histograms, there has not been a test until now that allows for the detection of differences between distributions, describes the difference and is sensitive to the location of the departures. Such a test could be critical for comparing pre-and post-event distributions, such as a change in the distribution of biomass due to fire, for example, or for comparing data from different locations, such as soil size distributions, and even for evaluating economic disparity or examining differences in age demographics. We present a new statistic, a departure index, which allows a test distribution to be compared with any reference distribution. The resulting index contains information about the location, magnitude and direction of departure from the reference distribution to the test distribution. The departure index in turn provides a standardized response range that allows for a comparison of results from different analyses. A case study of actual fire data demonstrates the sensitivity and range of the test.

Filamentous inclusions in acinar cell carcinoma of the pancreas.

Acinar cell carcinoma of the pancreas exhibits a spectrum of histologic appearances. Some tumors can be readily identified by light microscopy, but others resemble endocrine/neuroendocrine neoplasms. Ultrastructurally, though large zymogen granules of acinar cells are usually distinctive, the zymogen granules of neoplastic acinar cells are sometimes abnormally small, overlapping in size with the granules of endocrine/neuroendocrine neoplasms. Six cases of acinar cell carcinoma, two with a typical histologic appearance and four that resembled endocrine/neuroendocrine tumors, were studied ultrastructurally. In addition to zymogen granules and abundant rough endoplasmic reticulum, all cases of acinar cell carcinoma exhibited pleomorphic, membrane bound inclusions that contained filaments. Similar inclusions were not identified in islet cell or carcinoid tumors, and several findings indicate that the inclusions represent deranged zymogen granules. In the ultrastructural study of a pancreatic neoplasm with granules, these inclusions may provide a clue for the diagnosis of acinar cell carcinoma.

Negative images due to clofazimine crystals simulating MAI infection in a bronchoalveolar lavage specimen.

"Negative images" of bacilli in mycobacterial infections have been recently described in air-dried, Romanovsky-stained cytologic material. We report a case of negative images due to crystalline deposition of clofazimine, a drug used to treat Mycobacterium avium-intracellulare complex infection in AIDS patients. The negative images of clofazimine crystals seen in bronchoalveolar lavage (BAL) macrophages resemble the negative images of mycobacterial infection due to the pseudogaucher appearance of the cells. Crystals are distinguished by their refractile reddish appearance in unfixed, unstained smears, and by their birefringence on polarization. Crystals were found in both Pap-stained and Diff-Quik-stained smears and were negative with Ziehl-Neelsen stains. Clofazimine crystals in BAL specimens must be distinguished from the pseudogaucher type cells of mycobacterial infection in this patient population. We believe that this is the first report of clofazimine crystal deposition diagnosed in a BAL specimen along with electron microscopic examination of the cytologic material.

Fine needle aspiration biopsy of fibromatoses.

Fibromatoses form a spectrum of clinicopathologic entities characterized by the infiltrative proliferation of fibroblasts that lack malignant cytologic features. Fibromatoses present as nodular soft tissue masses almost anywhere in the body and thus are often amenable to fine needle aspiration (FNA). This report describes the FNA cytologic findings of fibromatosis in six patients ranging in age from 7 1/2 weeks to 36 years. Two of the lesions arose in the abdominal wall (musculoaponeurotic fibromatosis or extra-abdominal desmoid), and one each involved the plantar surface (Ledderhose's disease), the shoulder and the sternocleidomastoid muscle (Fibromatosis coli). The FNA of the shoulder was initially interpreted as nodular fasciitis due to the clinical presentation of a rapidly growing mass; an aspirate from the deep musculoaponeurotic region was believed to reveal a low grade sarcoma. The FNA diagnosis of musculoaponeurotic fibromatosis in a patient with familial polyposis coli suggested the diagnosis of Gardner's syndrome. Cytologically the aspirates consisted of groups of loosely cohesive, bland-appearing, spindle-shaped cells having oval to elongated nuclei and cytoplasmic tags. Individual spindle cells and rare inflammatory cells were also present. The aspirate of fibromatosis coli also contained degenerating skeletal muscle cells. Tissue confirmation was obtained in four cases. We believe that FNA is a useful procedure for the initial and recurrent diagnosis of fibromatoses and in the separation of fibromatoses from other benign and malignant soft tissue lesions. A discussion of other entities that enter into the cytologic differential diagnosis, such as mesenchymal repair, fasciitis and spindle cell types of sarcoma, is presented. From our experience we believe that the clinicopathologic features can suggest the diagnosis of fibromatosis, but histologic confirmation is recommended.

Fine needle aspiration of metastatic and hematologic malignancies clinically mimicking pancreatic carcinoma.

The fine needle aspiration (FNA) cytology findings in 19 cases of hematopoietic and metastatic neoplasms that radiographically mimicked primary pancreatic carcinoma are reported. These cases represented 11% of 176 malignant diagnoses in a series of 304 pancreatic FNAs. The cytologic diagnoses included 7 non-Hodgkin's lymphomas, 2 Hodgkin's lymphomas, 6 small cell carcinomas (4 lung, 1 gallbladder, 1 skin), 3 squamous cell carcinomas (2 cervix, 1 esophagus) and 1 hepatocellular carcinoma. In six cases the pancreatic lesion was the initial presentation of malignant disease. These included five lymphomas, which probably involved peripancreatic lymph nodes, and a metastatic small cell carcinoma of pulmonary origin. Recognition of unusual morphologic features of pancreatic carcinoma raised the possibility of extrapancreatic malignancies. Electron microscopy and immunocytochemistry performed on FNA specimens were helpful in selected cases. The FNA diagnosis of hematopoietic and metastatic neoplasms that clinically mimic pancreatic carcinoma prompts appropriate clinical studies and treatment and eliminates the need for open pancreatic biopsy and/or resection.

Alveolar cell carcinoma presenting as malignant pericardial effusion: diagnosis by electron microscopy.

The cytologic, immunocytochemical, and ultrastructural findings in a 68-year-old man who presented with a malignant pericardial effusion are reported. Radiologic studies failed to identify a primary neoplasm over the next 6 months. Ultrastructural examination of a repeat pericardiocentesis fluid specimen revealed cells with intranuclear tubular inclusions and cytoplasmic lamellar bodies typical of alveolar cell carcinoma. Review of the chest radiographs showed nonresolving patchy infiltrates in the upper lobe of the left lung clinically thought to represent pneumonia; in retrospect, however, these were consistent with the pneumonic form of alveolar cell carcinoma.

Neuroendocrine carcinoma of the oral cavity.

We report the clinical and pathologic features of a small cell neuroendocrine carcinoma arising in the oral cavity of a 63-year-old man. The tumor stained positively with neuron-specific enolase and had dense core granules ultrastructurally. Chemotherapy ordinarily given for pulmonary small cell carcinoma induced a clinical remission. When the tumor recurred 8 mo later, focal squamous differentiation was present within the neuroendocrine carcinoma. The patient died 2.5 yr after presentation.

Asbestos bodies in pulmonary hilar lymph nodes.

Asbestos bodies (AB) have long been recognized in light microscopic (LM) sections of pulmonary hilar lymph nodes (LN) from patients with asbestos-related diseases, but the presence of AB on LM has not been correlated with the lung AB burden. The purpose of the present study was to determine whether AB in histologic sections of LN are indicative of heavy lung asbestos burdens. Twenty cases (17 with asbestosis, 15 with carcinoma of the lung, and two with malignant pleural mesothelioma) with at least one AB on a hilar LN section were identified. Bleach digestion of lung tissue in 15 cases demonstrated a median of 24,000 AB/g by LM and 44,000 AB/g by scanning electron microscopy. Digestion of hilar nodes demonstrated 21,800, 15,500, and 3,200 AB/g by LM in three cases which had lung burdens of 22,000, 481,000, and 5470 AB/g, respectively. A fourth LN specimen contained 322,000 AB/g in a case with no lung available to digest. Mean AB lengths in the LN in three cases were 48, 45, and 27 microns. Fourteen control cases of men over 50 without known asbestos exposure or asbestos-related disease had no AB in LN sections even after staining for iron. Among fourteen patients with parietal pleural plaques and an elevated lung asbestos body content, AB were observed in iron-stained LN sections in only two cases. These two patients had 3240 and 610 AB/g lung tissue, respectively (normal range 0 to 20 AB/g). We conclude that the finding of AB on a histologic section of hilar LN is generally indicative of a heavy lung AB burden.(ABSTRACT TRUNCATED AT 250 WORDS)

Microprobe analysis of chlorpromazine pigmentation.

We describe the histochemical, ultrastructural, and microanalytical features of a skin biopsy specimen obtained from a patient with chlorpromazine pigmentation. Golden-brown pigment granules were present in the dermis, predominantly in a perivascular arrangement. The granules stained positively with the Fontana-Masson stain for silver-reducing substances and negatively with Perl's stain for iron. Electron microscopy revealed dense inclusion bodies in dermal histiocytes, pericytes, endothelial cells, and Schwann cells, as well as lying free in the extracellular matrix. These "chlorpromazine bodies" were quite dense even in unosmicated, unstained ultrathin sections, indicating that the pigmentation is related, at least in part, to the inclusions. Microprobe analysis of the chlorpromazine bodies revealed a striking peak for sulfur, which strongly suggests the presence of the drug or its metabolite within these inclusions.

Biochemical and ultrastructural differences between muco-epidermoid and carcinoid tumors of the bronchus.

Bronchial adenomas have been classified into three types: carcinoid tumors, cylindromas (adenoid cystic carcinomas), and mucoepidermoid tumors. Studies from our laboratory have demonstrated that the quantitative measurement of monoamine oxidase (MAO) in homogenates of carcinoid tumors of foregut origin is different than the activity enzymes in other tumors of neural crest origin. In this study we compared the biochemical composition of 12 bronchial carcinoid tumors with the biochemical composition of a rare mucoepidermoid adenoma of the bronchus. Electron microscopy revealed that some cells of the mucoepidermoid adenoma contained mucin and tonofilaments; none of the cells contained neurosecretory granules. The MAO activity of the bronchial carcinoid tumors was much higher than the MAO activity of the mucoepidermoid adenoma. Thus, there are distinctive ultrastructural and biochemical differences in these two types of bronchial adenomas.

Cartilaginous variant of congenital adenomatoid malformation of the lung.

We report the occurrence of an unusual variant of congenital adenomatoid malformation (CAM) of the lung in a 16-year-old male. Abundant cartilage in the walls of malformed bronchioles, an extremely rare finding in CAM, distinguishes this lesion from the usual forms. We present the roentgenographic, computed tomographic, and pathologic features of this lesion as well as its embryologic implications. In addition, two similar cases are reviewed, one of which has been briefly discussed in a previous publication. Cartilaginous CAM should be distinguished from another lesion with abundant cartilage, the so-called pulmonary hamartoma.