Inappropriate mucin production in gall bladder metaplasia and neoplasia--an immunohistological study

Gallbladder mucocele caused by intestinal metaplasia in lithiasic cholecystitis: A case report and literature review of a rare association

INTRODUCTION

Mucin hypersecretion promoted by intestinal metaplasia can lead to gallstone formation. The presence of large amounts of mucin induced by a change in biliary epithelium structure is called a mucocele, a usually benign condition studied among animals but rarely described in humans. This entity must be distinguished from hydrops, a condition secondary to an impacted gallstone in the cystic duct leading to an outlet obstruction and distension of the gallbladder.

PRESENTATION OF CASE

We report a case of a 51-year-old female with lithiasic cholecystitis showing areas of intestinal metaplasia associated with a mucocele. Laparoscopic cholecystectomy was performed with an uneventful postoperative course. Macroscopic findings revealed a dilated gallbladder filled with mucoid fluid. Signs of chronic and focally acute cholecystitis with areas of intestinal metaplasia were observed microscopically.

DISCUSSION

Lithiasic gallbladders can bear a gene that is found in goblet cells of intestinal metaplasia, leading to mucin hypersecretion. Metaplasia - a benign lesion often encountered on cholecystectomy specimens - can be the precursor of carcinoma. Mucin-producing gallbladder carcinoma is a very aggressive tumor that can appear as a mucocele. Consequently, preoperative computed tomography or magnetic resonance cholangiopancreatography should be performed in the presence of an unusual aspect on sonography.

CONCLUSION

Metaplastic changes in gallbladder epithelium associated with an overproduction of mucin and lithiasic cholecystitis reported in this case is a rarity. Malignancy is an alternative diagnosis of gallbladder mucocele that must be suspected whenever preoperative imaging of the gallbladder is atypical.

Sclerotherapy of Edematous Gallbladders with Different Agents

Different sclerosing agents were tried in experiments with 32 pigs to achieve ablation of gallbladders rendered edematous by mechanical lithotripsy with the Rotolith lithotriptor. In 16 pigs sclerotherapy was performed with 6% acetic acid, Carnoy's solution, 95% ethanol + 3% sodium-tetradecylsulfate (STS) and hot metrizoate, respectively. These animals were sacrificed immediately after the procedure. Histologic examination showed persistent surface epithelium and glandular epithelium in all specimens. In 6 pigs, the sclerotherapy was done with Carnoy's solution, 95% ethanol + 3% STS and hot metrizoate, respectively, and the pigs were killed 6 days later. Fibrosis of the gallbladder remnants was seen in these animals, but also remnants of surface and glandular epithelium. Hot metrizoate was used in another 10 pigs and these animals were sacrificed after 8 weeks. At histologic examination fibrosis was seen in the gallbladder remnants of 9 surviving animals, but also areas of preserved muscular layer, and development of mucinous cysts were found in more than 50% of the specimens. Thus, none of the sclerosants was able to produce a total ablation of the gallbladder mucosa.

Distribution of gland-like structures in human gallbladder adenocarcinomas possesses fractal dimension

BACKGROUND AND OBJECTIVES

Epithelial cells form tissue patterns of higher order such as gland-like structures. A question arises whether distribution of those patterns in adenocarcinomas is subject to certain regularity.

METHODS

Due to the pilot nature of this study, gallbladder adenocarcinomas were preselected by histopathological, immunohistochemical, and morphometric analysis to ensure relative homogeneity of the patterns analyzed. A box-counting method was applied to investigate a relationship between a number of gland-like structures and a radius of the expanding family of the concentric circles.

RESULTS

The coefficient of linear regression characterizing that relationship possesses noninteger value. It is 1. 585 (well-differentiated adenocarcinomas, standard deviation (SD) = 0.038, n = 100 sections), and 1.340 (moderately differentiated adenocarcinomas, SD = 0.044, n = 100 sections). While both nuclear area and nucleo-cytoplasmic ratio in those tissues remain within a similar range (Analysis of Variance (ANOVA), F(0) = 0.791 < F(alpha) = 3.84, P = 3 x 10(-3) and F(0) = 0.077 < F(alpha) = 3.84, P = 10(-6), respectively, for k = 20,000 cells, in which F(0) is a value of the test function, F(alpha) is a critical, limit value of the F-test at the constant confidence value alpha = 0.05), a difference of fractal dimension is significant (F(0) = 3.94 > F(alpha) = 0.693, n = 100 sections, P = 2 x 10(-3)). Also, variablity of fractal dimension between tumor sections is significant (moderately differentiated adenocarcinomas, F(0) = 1.9856 > F(alpha) = 1.4262, n = 100 sections, P = 0.189).

CONCLUSIONS

There is fractal regularity in distribution of gland-like structures in human gallbladder adenocarcinomas. Fractal dimension is a holistic parameter which can be applied to evaluate tumor grading in a quantitative manner.

Ultrastructural aspects of human gallbladder epithelial cells in cholelithiasis: production of anionic mucus

The surface epithelium of 28 gallbladders removed during elective cholecystectomies and pathology collection was studied ultrastructurally. Focusing on 10 of the 28 cases that were diagnosed as cholecystitis, we found that the epithelium displayed numerous apical mucous granules and bulging apical apices. Mucous granule changes included 1) hyperproduction of secretory granules of neutral type containing an electron-dense proteinaceous spherule, similar to that described in other mucus-producing glands of the digestive system, and 2) production of anionic, osmiophilic secretory mucus. Other alterations of the surface epithelial cells included the production of bizarre surface appendages resembling primitive cilia without axoneme and epithelial excrescences.

Metaplasia and precursor lesions of gallbladder carcinoma. Frequency, distribution, and probability of detection in routine histologic samples

BACKGROUND

Gallbladder diseases, especially cholelithiasis, are extremely frequent in Chile, and an increasing frequency of gallbladder carcinoma has been observed during the last decades. Hyperplastic and atypical epithelial lesions of gallbladder epithelium have been considered potential precursors of invasive carcinoma. The current study was designed to study the frequency, distribution, extension, and probability of routine detection of potentially preneoplastic changes of gallbladder epithelium.

METHODS

Epithelial changes were histologically studied by mapping gallbladders obtained at elective cholecystectomy for lithiasis in 162 Chilean patients.

RESULTS

Antral-type metaplasia was found in 95.1% of the cases, intestinal metaplasia in 58.1%, hyperplasia in 46.9%, dysplasia in 16%, and carcinoma in situ in 2.5%. A significant association of intestinal metaplasia with hyperplasia, intestinal metaplasia with dysplasia, and hyperplasia with dysplasia was found. Hyperplasia and dysplasia were also present in four cases with carcinoma in situ. Mean extension of the lesions (percentages of the sections in which the change was observed) was antral-type metaplasia (62.7%), intestinal metaplasia (25.3%), hyperplasia (24.1%), dysplasia (15.5%), and carcinoma in situ (9.7%). Antral-type and intestinal metaplasia were more extensive and more severe in patients older than 50 years of age. Hyperplasia was more extensive in cases in which it was associated with dysplasia and carcinoma in situ.

CONCLUSIONS

The extension of metaplasia seems to depend in part on the age of the patients. The association of intestinal metaplasia with hyperplasia and dysplasia agrees with the findings of other authors that relate metaplasia to gallbladder cancer. The epithelial lesions are focal or partially confluent, thus a single random histologic section will detect less than one third of the hyperplasias, dysplasias, and carcinomas in situ.

Intestinal mucin antigens in ulcerative colitis and their relationship with malignancy

The expression of two intestinal mucin-associated antigens large intestine mucin antigen (LIMA) and small intestine mucin antigen (SIMA) were investigated by indirect immunoperoxidase staining of rectal mucosa from patients suffering from ulcerative colitis with (n = 6) and without (n = 31) associated carcinoma and in noncolitic controls (n = 40). The aim was to assess the relationship between antigen patterns and malignant change. SIMA, which is localised predominantly in the small intestine, is virtually undetectable in the normal adult colonic mucosa. However, this antigen is present in the foetal colon and colonic carcinoma. LIMA is expressed in normal colonic mucosa, but absent from the small intestine. LIMA staining patterns were not significantly different among the three groups. In contrast, expression of SIMA was significantly higher in the patients who had developed carcinoma (6/6) than in the noncancer group (7/71) (P less than 0.001). The presence of SIMA was also significantly related to areas of dysplasia compared to normal (P = .03) or inflammation (P less than .05), but it did not differ from mucosa showing "indefinite" atypia. The finding of 31% SIMA-positive biopsies associated with severe inflammation in colitis with active disease, but no evidence of malignancy, is difficult to explain at the present stage. A followup study would be necessary to determine its significance. Perhaps the most important finding is the increased frequency of SIMA-positive foci in histologically normal mucosa in carcinoma patients compared with the noncancer group (P less than .001), suggesting a field change. These observations may be prove useful for the identification of patients who may be at risk of developing carcinoma.

The histogenesis of adenocarcinoma of the gallbladder

A prospective study of 277 cholecystectomy specimens for evidence of isolated epithelial dysplasia of gallbladder mucosa is presented. In addition, 15 cases of primary adenocarcinoma of the gallbladder are retrospectively reviewed with particular reference to the presence of metaplasia and dysplasia adjacent to the infiltrating tumor, in order to establish the relationship between metaplasia, isolated epithelial dysplasia, and adenocarcinoma of the gallbladder. Only one case of isolated epithelial dysplasia was found in the 277 cholecystectomy specimens, and this arose within focal incomplete intestinal metaplasia. In the 15 cases of adenocarcinoma of the gallbladder, benign antral and/or incomplete intestinal metaplasia was found adjacent to the tumor in 11 cases. In 10 cases, dysplasia of this metaplastic epithelium was found in continuity with the tumor. The authors conclude that the most common pathway to adenocarcinoma is via dysplasia of metaplastic gallbladder epithelium.

Intestinal metaplasia of the gallbladder: a morphologic and immunocytochemical study

The morphologic spectrum of intestinal metaplasia was studied in 49 gallbladders that had been excised because of cholelithiasis. Based on the absence or presence of endocrine cells, the cases of intestinal metaplasia were arbitrarily divided into two groups. The gallbladders from the first group (26 cases) contained isolated or small clusters of mature goblet cells, while those from the second group (23 cases), in addition to the goblet cells, contained argyrophil and argentaffin cells and, less frequently, Paneth cells and gland-like structures similar to colonic crypts. Pseudopyloric glands and superficial gastric-type epithelium were present in both groups. Argyrophil cells outnumbered argentaffin cells by a ratio of 4 to 1. By immunocytochemical methods serotonin-containing cells were found to be the most common endocrine cells. Other endocrine cells showed immunoreactivity for somatostatin, cholecystokinin, gastrin, and pancreatic polypeptide. The presence of gut endocrine cells and Paneth cells in the pseudopyloric glands suggests that these glands are also an integral component of intestinal metaplasia of the gallbladder. The findings support the hypothesis that cholelithiasis induces the appearance of a stem endodermal cell that, in turn, may differentiate into cells with mature intestinal or gastric phenotypes.

Spontaneous lesions of the mouse biliary tract

During the routine histological examination of 2400 aged mice from lifespan carcinogenicity studies a low prevalence of glandular metaplasia of the gall bladder and of the intra-hepatic bile ducts (all associated with cholelithiasis), cholecystitis, cholangitis, papillomatous hyperplasia, papilloma, intra-mural cysts, and focal epithelial ulceration was found. The lesions were found predominantly in female mice and were not treatment related.

An immunocytochemical study of the distribution of lysozyme, a1-antitrypsin and a1-antichymotrypsin in the normal and pathological gall bladder

We have studied the distribution of lysozyme (Ly), a1-antitrypsin (a1AT) and a1-antichymotrypsin ( a1AChy ) in the normal, chronically inflamed and neoplastic gall bladder mucosa using the peroxidase-anti-peroxidase (PAP) method. Ly was absent from the normal mucosa but it was found only in areas of glandular metaplasia of true antral type and in crypts of possible early metaplastic nature in cases of chronic cholecystitis. a1AT and a1AChy were also found in such metaplastic areas, but their presence was also observed immunohistochemically in areas of essentially normal and in non-metaplastic, chronically inflamed gall bladder mucosa. The possible local production of these substances by gall bladder epithelial cells is discussed. Ly, a1AT and a1AChy were also found in various histological types of adenocarcinoma of the gall bladder in varying degrees of frequency and intensity, unrelated to the histological type and invasiveness of the tumour.

Carcinoembryonic antigen in skin and related tumours as determined by immunohistological techniques

Common benign skin abnormalities and related tumours were investigated for the presence of carcinoembryonic antigen (CEA) using immunohistological techniques in formalin-fixed tissue. CEA could be detected in all 10 squamous cell carcinomas examined, a finding which contrasted with those in earlier reports. CEA was not seen in normal skin but was present in the skins of 12-18-wk-old fetuses. Hence, CEA can be considered to be a true oncofetal antigen for ectodermal tissue. The antigen was not detected in seborrheic keratoses but was present in all 10 cases of keratoacanthoma. CEA was found in only one out of 10 basal cell carcinomas, the tumour being metatypical (basosquamous) in type. CEA was also observed in the minority of cases of solar keratosis and Bowen's disease. If the presence of CEA in proliferating epidermal tissue is associated with malignant transformation, both solar keratosis and Bowen's disease are indeed premalignant lesions whilst keratoacanthoma is the non-metastasizing variant of squamous cell carcinoma. Finally, the absence of CEA in basal cell carcinoma may help to explain its 'reluctance' to spread by metastasis.

Carcinoembryonic antigen in normal, preneoplastic and neoplastic gallbladder epithelium

Carcinoembryonic antigen (CEA) was found in normal epithelium, premalignant lesions, and all histologic types of carcinomas of the gallbladder. Immunocytochemical staining for CEA was limited to the apical surface of normal epithelium. In premalignant lesions and in carcinomas, the staining was more extensive, occurring within the cytoplasm and gland secretions. These findings show that the presence and the pattern of distribution of CEA in normal and neoplastic gallbladder epithelium closely resemble that in other gastrointestinal epithelia.

Histogenesis of epithelial neoplasms of human gallbladder II. Classification of carcinoma on the basis of morphological features

The material consisted of 83 gallbladders with primary carcinoma. Non-malignant bordering mucosa was present in 37 specimens and in 34 of these (92%) it was metaplastic, mostly (78.4%) of antral type. In all but one case the bordering epithelium contained dyplasias of different degrees and thus the dysplasia had manifested in metaplastic epithelium. According to their degree of differentiation, the carcinomas were divided in three groups. In groups 1 and 2 the structure was intestinal. Group 1, which had the highest degree of differentiation, contained papillary and glandular structures. Group 2 contained similar glandular structures but, unlike group 1, no goblet and no enterochromaffin cells. In group 3 (anaplastic carcinomas) the mode of growth was infiltrative or solid. The amount of mucin decreased with the degree of differentiation. Histochemically, there were no differences between the groups, but the mucin was mainly non-sulphated acid mucin as in the metaplastic and dysplastic areas surrounding the tumour, thus differing from the normal gallbladder epithelium containing sulphated acid mucin. In 52 cases it was possible to investigate the superficial part of the tumour. The carcinoma structure was of a high degree of differentiation (group 1) in 29 (55.8%) cases, which all had structures of group 2 in the deeper layers. These results indicate that the structure of the carcinoma is not permanent, it dedifferentiates at the deeper invasive layers. In only two cases (3.8%) was the anaplastic structure of group 3 already on the surface without the intermediate stages of groups 1 and 2.

Inappropriate mucin production in endodermal carcinoma--one point of view

The mucosal lining cells in the gastrointestinal tract respond to a threatening situation by secreting mucins manufactured during foetal life and this secretion is considered to be an early manifestation of cytogenetic instability and which may be the first step in the process of malignant transformation. Using immunohistological techniques and specific antisera against SIMA (small intestinal mucin antigen), LIMA (large intestinal mucin antigen) and CEA (carcinoembryonic antigen) the presence of these mucin antigens was studied in resected specimens from colonic, gastric and gall bladder carcinomas as well as in mucinous tumours of the ovary. Inappropriate or oncofoetal mucins were present in the majority of endodermal carcinomas, in associated metaplastic epithelium and premalignant lesions such as polyps. These antigens were also demonstrated in normal histological epithelium at some distance from the tumour. These findings lead to a better understanding of the biological behaviour of preneoplastic lesions of endodermal tissues and will aid in developing sensitive diagnostic tests for the presence of these substances.

Mutagens: some possible health impacts beyond carcinogenesis

Considerable attention is currently being given to the roles of environmental and endogenous mutagens in tumor induction and in tumor progression through the abilities of mutagens to induce one or another kind of somatic mutation. It is proposed here that mutagens, also through induction of somatic mutations, initiate a spectrum of additional, much more common, focal lesions that are important to the human condition. While individually they are of relative insignificance and thus neglected by many clinicians, the functional attributes of these focal lesions have important impacts on human physiology and thus contribute substantially to the process of aging. Additionally, one individual focus may progress to an extent that it produces clinically recognizable symptoms and may even jeopardize the carrier's life. The ultimate and developed expression of these lesions is heterogeneous, is far removed in time from initial induction, and relies on additional host and environmental factors for expression; therefore, the possible role of somatic mutation is readily overlooked. The focal lesions reviewed are fibrous atherosclerotic plaques, senile cataracts, and metaplasias. Literature that implicates metaplasias as precursor or as predisposing lesions in the ultimate formation of gallstones, duodenal ulcers, and adenocarcinomas is summarized.

Intestine-associated antigens in ovarian tumours: an immunohistological study

The presence of 3 intestine-associated antigens, small intestine mucin antigen (SIMA), large intestine mucin antigen (LIMA) and carcinoembryonic antigen (CEA) was studied in the female genital tract and ovarian tumours by immunofluorescence. These antigens could not be detected in normal ovary, benign cysts of ovary, fallopian tube or endometrium, but both LIMA and CEA were present in endocervical glandular tissue. The antigenic cross-reactivity of endocervical and large bowel mucin may indicate a close embryological relationship between these organs during the cloacogenic stage. The 3 antigens could be demonstrated in mucinous tumours of the ovary but were absent in serous or mesonephroid tumours. In one of the 2 endometroid tumours CEA was the only detectable antigen. These observations confirm the presence of intestinal type of epithelium in cystic mucinous tumours of the ovary and explain the cross-reactivity of mucin of benign tumours of the ovary and mucin from colonic cancer, normal colonic mucosa and gastric mucosa as reported by earlier workers. In the process of malignant transformation the columnar epithelium of ovarian cystadenoma seems to behave in the same way as superficial gastric and gall bladder epithelium by forming inappropriate intestine-associated mucin substances. Our technique may provide a specific means for studies on the histogenesis of female genital tract tumours, particularly ovarian tumours. It can also be used in differentiating between benign and malignant variants of these tumours.