Retrospective histochemical study of mucosubstances in adenocarcinomas of the gastrointestinal tract

3'-sulfated LewisA/C: An oncofetal epitope associated with metaplastic and oncogenic plasticity of the gastrointestinal foregut

Metaplasia, dysplasia, and cancer arise from normal epithelia via a plastic cellular transformation, typically in the setting of chronic inflammation. Such transformations are the focus of numerous studies that strive to identify the changes in RNA/Protein expression that drive such plasticity along with the contributions from the mesenchyme and immune cells. However, despite being widely utilized clinically as biomarkers for such transitions, the role of glycosylation epitopes is understudied in this context. Here, we explore 3'-Sulfo-Lewis A/C, a clinically validated biomarker for high-risk metaplasia and cancer throughout the gastrointestinal foregut: esophagus, stomach, and pancreas. We discuss the clinical correlation of sulfomucin expression with metaplastic and oncogenic transformation, as well as its synthesis, intracellular and extracellular receptors and suggest potential roles for 3'-Sulfo-Lewis A/C in contributing to and maintaining these malignant cellular transformations.

The Histochemical Alterations of Mucin in Colorectal Carcinoma Quantified by Two Efficient Algorithms of Digital Image Analysis

The practical use of knowledge on the diagnostic-prognostic role of polysaccharide components of mucins in colorectal cancer (CRC) has been difficult, due to the number of histochemical (HC) reaction types, as well as lack of standard methods of computer-assisted analysis of tissue expression of these molecules. Using two algorithms of digital image analysis (by application of Image-Pro Premier and our originally designed program Filter HSV), we evaluated the expression of polysaccharides in tissue samples of CRC patients (n = 33), and fragments of normal colorectal tissue from the same patients (control) using periodic acid Schiff reaction (PAS) (neutral mucins) and alcian blue staining (AB) (acidic mucins). Our results indicate lower expression of the PAS+ and AB+ mucins in CRC, as compared to the control samples. The higher expression of PAS+ polysaccharides was detected in flat tumors than in protruded CRC, while higher AB+ mucins expression was a feature of mucinous CRC subtypes. Positive correlation between mutual PAS+ and AB+ expression, as well as correlations with glucose concentration (PAS+ mucins), and hemoglobin level (AB+ mucins) were observed exclusively in unchanged colorectal samples (control). Both algorithms of digital image analysis (smart segmentation and Filter HSV) work properly and can be used interchangeably in daily practice of pathologists, as useful tools of quantitative evaluation of HC reaction in both normal and cancerous tissues.

Histochemical Study of Mucinous Ovarian Cystomas of Intestinal and Mixed Types: O-Acetylated Sialomucin Content in Relation to Biologic Behavior

The subgroup of mucinous ovarian cystomas of intestinal type containing site 8 O-acetylated sialomucins and its relation to malignant behavior were studied. Of 75 mucinous cystomas of the ovary from the files of the Institute of Pathological Anatomy and Histology (University of Genoa), 54 were endocervical, 19 were mixed, and 2 were intestinal. As regards their histologic pattern, the 54 mucinous endocervical cystomas were benign, whereas the 19 mixed type group included 8 benign, 5 borderline and 6 malignant; the 2 intestinal type tumors were borderline. According to histochemical investigations, the frequency of tumors with goblet cells containing site 8 O-acetylated sialomucins (positive to PB/KOH/PAS) was 47% In the mixed type cystomas and 100% in the intestinal type cystomas. Twenty-five percent of benign mixed cystomas, 60 % of borderline mixed cystomas, and 67 % of mixed cystadenocarcinomas were positive to PB/KOH/PAS. One hundred percent of the borderline cystomas of intestinal type were positive. Our results confirm that among mucinous ovarian cystomas, those containing intestinal type epithelium are the most likely to fall within the borderline or malignant categories. Moreover, of all ovarian cystomas of intestinal type, those characterized by site 8 O-acetylated sialomucins seem to be more aggressive and, in general, to have a more malignant behavior than the mucinous cystic tumors of müllerian or endocervical type.

DNA content in human colon cancer and non-neoplastic adjacent mucosa

DNA content was determined by flow cytometry in a series of 51 paired fresh tissue samples of primary colorectal carcinomas and the respective non-neoplastic adjacent mucosa in order to assess the relationship between DNA ploidy and the most commonly used prognostic factors. Aneuploidy was observed in 70.6% of the tumors and more than one aneuploid peak was present in 3.9%. Aneuploid tumor frequency was higher in left (93.3%) and right colon (64.7%) cancers than in rectal carcinomas (60.0%), and multiple aneuploid clones were detected more frequently in men than in women and in patients with advanced disease (Dukes stage D). Non-neoplastic mucosa adjacent to aneuploid tumors showed aneuploidy in 4 out of 51 samples (7.8%). The mucosa adjacent to diploid cancers had only diploid characteristics. Polidy did not correlate with histological abnormalities.

These findings suggest that DNA content as determined by flow cytometry needs further study with adequate follow-up to evaluate possible correlations with relapse-free and overall survival. Furthermore the aneuploidy of non-neoplastic mucosa provides evidence for a field defect in mucosa adjacent to colorectal cancer and supports the concept that this alteration may be of influence on carcinogenesis.

Mucinous (colloid) adenocarcinomas secrete distinct O-acylated forms of sialomucins: a histochemical study of gastric, colorectal and breast adenocarcinomas

AIMS

Mucinous (colloid) adenocarcinomas represent a distinct group of tumours defined by the presence of large amounts of extracellular mucins. By using histochemical methods, we analysed mucins secreted by mucinous versus non-mucinous adenocarcinomas and looked for differential secretion profiles.

METHODS AND RESULTS

Sixty-four adenocarcinomas were studied (23 colorectal, 17 gastric, and 24 breast tumours). Thirty-two tumours were of the colloid type. The following methods were applied to paraffin tissue sections: (i) Alcian blue (pH 2.5) and periodic acid-Schiff (PAS); (ii) high iron diamine and Alcian blue (pH 2.5); (iii) periodic acid borohydride, potassium hydroxide, and PAS; (iv) periodic acid-thionine Schiff, potassium hydroxide, and PAS; and (v) periodic acid-borohydride and PAS. Most adenocarcinomas secreted acidic mucins, with sialomucins predominating over sulfomucins, except for non-mucinous adenocarcinomas of the breast which showed predominant neutral mucins. All mucinous adenocarcinomas contained C9-O-acyl sialic acid as mono, di(C8,C9)-, or tri(C7,C8,C9)-O-acyl forms. Acidic mucins secreted by the majority of non-colloid adenocarcinomas consisted of non-O-acylated sialomucins.

CONCLUSIONS

C9-O-acylation of sialic acid is a characteristic feature of mucinous adenocarcinomas and can be readily detected by histochemical methods.

Precursors of gastric carcinoma: a critical review with a brief description of early (curable) gastric cancer

Gastric adenocarcinoma is among the most common malignancies worldwide. Its etiopathogenesis is complex and, as yet, incompletely understood; however, diet, infection with Helicobacter pylori, and genetic factors are involved. It may be classified into two main types, intestinal and diffuse. The intestinal type has decreased in incidence, whereas the diffuse tumors as well as those confined to the cardia are increasing. Numerous conditions, such as gastritis, gastric atrophy, and intestinal metaplasia (IM), are associated with intestinal type gastric cancer in retrospective studies, but only epithelial dysplasia has a positive predictive value for malignancy. These precursor conditions and lesions are analyzed for their clinicopathological significance in this review, which concludes with a brief summary of curable (early) forms of gastric cancer.

Abnormal DNA ploidy and proliferative patterns in superficial colonic epithelium adjacent to colorectal cancer

Superficial colonic cells were taken from normal-appearing mucosa at 2, 5, and 10 cm proximal and distal to colorectal cancer margins in 37 patients. The DNA ploidy and proliferative pattern of each sample were determined using flow cytometry. In 11 patients, histology of mucosal sections from the same sites also was analyzed. We found a higher frequency of aneuploidy than previously reported in mucosa up to 10 cm from a colorectal cancer; 62% (23/37) of the primary cancers were aneuploid, and of these, 48% (11/23) were associated with adjacent aneuploid mucosa. The mucosa adjacent to the 14 diploid cancers had only diploid characteristics. The proliferative activity (as reflected by synthetic (S) phase fraction) of aneuploid cancers (21.1 +/- 2.0% SEM) and aneuploid mucosa as far as 10 cm away (21.2 +/- 2.1% SEM) was higher than in normal controls (10.2 +/- 0.7% SEM) (P less than 0.0005). Parallel cytology excluded shed cancer cells as an explanation for these findings. Histology showed diffuse, generally mild and reactive, mucosal abnormalities in eight of 11 patients. Ploidy did not correlate with histologic abnormalities. The findings of aneuploidy and high S-phase fraction in uninvolved superficial mucosa provide evidence for a field defect in mucosa adjacent to colorectal cancer and support the concept that the large bowel mucosa behaves as a unit in carcinogenesis.

Mucin histochemistry of virus-induced duodenal adenomas in guinea fowl

The type of mucoproteins in virus-induced duodenal adenomas in guinea fowl were compared with those in the normal duodenal mucosa. The mucin-producing cells in the latter contained a mixture of acid and neutral mucins. Neutral and sulphomucins prevailed in the crypts and in the lower part of the villi, while the amount of the sialomucins increased progressively toward the tip of the villi. In the adenomas, goblet cells were more numerous and were unevenly distributed. In their mucin profile the deeply located tumor glandular structures resembled normal crypts and lower parts of the villi and superficial portions of the adenomas were similar to the upper part of the villi. Qualitative changes in the mucin secretion with deviation from the normal vertical distribution of mucin types were rarely observed. The histochemical study carried out supplemented the histological characterization of the virus-induced duodenal adenomas and contributed to the elucidation of some aspects of their histogenesis.

Regional distribution of glycoconjugates in normal, transitional and neoplastic human colonic mucosa. A histochemical study using lectins

Regional distribution of glycoconjugates in normal and neoplastic colonic mucosa was studied by means of eight lectins: Dolichos biflorus (DBA), Glycine max (SBA), Triticum vulgare (WGA), Arachis hypogaea (PNA), Griffonia simplicifolia-I (GS-I), Canavalia ensiformis (Con A), Limax flavus (LFA), and Ulex europaeus-I (UEA-I). The lectin binding patterns were examined in 40 normal colonic mucosa (NM) (12 proximal (P) and 28 distal (D], 38 carcinomas (15 P and 23 D), and 31 transitional mucosa (TM) (9 P and 22 D). Sections of NM located 5 cm and 10 cm distant from the tumour and sections from the resection margins (more than 10 cm from the tumour) of the surgical specimens were also studied in 19 cases (6 P and 13 D). In NM, regional differences between the proximal and distal colon were detected with most lectins. DBA, SBA and LFA bound mainly to the goblet cell mucin of the distal colon, while GS-I and UEA-I labelling predominated in proximal colonic mucosa. The lectin reactivity in carcinomas was: DBA 26%, SBA 63%, PNA 95%, GS-I 66%, UEA-I 76%, WGA 100%, Con A 92% and LFA 42%. No regional differences were observed in the lectin patterns of proximal and distal colonic carcinomas nor was any relationship detected between lectin reactivities and Dukes stage, size or histological type of tumours. Transitional mucosa of both the proximal and distal colon showed an increase in PNA-binding and loss of DBA and SBA. LFA and UEA-I reactivity in proximal TM was similar to that observed in proximal NM. Distal TM showed a decrease in LFA labelling and the appearance of UEA-I reactivity in goblet cell mucin in 5 cases (23%). The reactivity of the other lectins was as with NM. The only change in normal mucosa distant from tumours was a focal increase in PNA reactivity in 4 cases. These findings suggest that carcinomas from different colonic regions have a more uniform distribution of carbohydrates than the respective NM.

Mucin profiles in ulcerative colitis with dysplasia and carcinoma

Mucin secretion was assessed in Crohn's colitis, in ulcerative colitis with regeneration, dysplasia and carcinoma and in non-colitic adenocarcinoma. The high iron diamine-alcian blue (HID-AB) and periodate borohydride-saponification periodic acid Schiff (PB-KOH-PAS) techniques were used to demonstrate sulphomucins and sialomucins, and O-acylated sialomucins respectively. There was mucosal hyperplasia and increased sialomucin secretion in Crohn's disease, quiescent and active ulcerative colitis. In colitis with carcinoma inflamed mucosa away from the tumour had increased sialomucins as had colitis with dysplasia. They did not differ statistically from each other or from colitic controls without cancer. Dysplastic crypts frequently secreted sulphomucins and the increased sialomucins were in transitional-like glands in the surface fronds or adjacent to the dysplasia. A comparative study of the HID-AB technique gave total correct qualitative allocation of individual quantitatively assessed crypts. Routine HID-AB staining did not aid the recognition of dysplasia in ulcerative colitis. With the PB-KOH-PAS technique colorectal adenocarcinoma showed a significant diminution in O-acylated sialomucins compared with its adjacent mucosa. Mucosal dysplasia in ulcerative colitis displayed a similar trend in O-acylated sialic acid variants, differing with respect to age-and sex-matched colitic controls. The PB-KOH-PAS technique may be of help in assessing mucin secretion in ulcerative colitis as a guide to the evolution of malignancy.

Nippostrongylus brasiliensis: histochemical changes in the composition of mucins in goblet cells during infection in rats

Changes in the quality of mucins in jejunal goblet cells were investigated during an infection with Nippostrongylus brasiliensis in rats. At 10 days after infection, when proliferative activity in the crypts is excessive and both crypts and villi are characterized by hyperplasia of goblet cells, the histochemical composition of the population of goblet cells in comparison with controls shows a marked increase in crypt and villous goblet cells containing neutral mucins. At 15 days after infection both crypts and villi display a significant increase in goblet cells containing acid mucin and decrease in goblet cells containing neutral mucin. The acid mucins in crypt and villous goblet cells on day 15 appear to be sulphomucins predominantly, whereas in controls sialomucin-containing goblet cells dominate both in the crypts and on the villi. These experiments establish that the explusion of N. brasiliensis from the intestine of the rat coincides not only with quantitative, but also with remarkable qualitative changes in the histochemical composition of mucins in goblet cells.

Histochemical changes in the composition of mucins in goblet cells during methotrexate-induced mucosal atrophy in rats

Changes in the composition of mucins in jejunal goblet cells were investigated histochemically after a single intraperitoneal injection of methotrexate in rats (40 mg methotrexate/kg body weight). At 48 h after injection of methotrexate, when mitotic activity in the crypts approximates to zero, an almost complete disappearance of mucin-containing goblet cells can be observed. At 96h, when proliferative activity in crypts is excessive, neutral mucin- and sialomucin-containing goblet cells dominate in the crypts, whereas in controls the crypts display sulphomucin-containing goblet cells. At 144h neutral mucin- and sulphomucin-containing goblet cells dominate in the crypts. Both at 48 and 96h after injection of methotrexate a significant decrease in the number of villous goblet cells takes place, whereas with respect to the quality of the mucins in the goblet cells no difference can be found in comparison with control rats. At 144h the villi have recovered from the preceding temporary decrease of goblet cells. The histochemical composition of the population of goblet cells is still aberrant and shows goblet cells containing neutral mucins and sulphomucins principally, whereas in controls sialomucin-containing goblet cells dominate on the villi. The established changes in the composition of mucins in goblet cells cannot be attributed to methotrexate-induced malnutrition, as pair-fed control rats clearly demonstrate. Our results clearly demonstrate that conspicuous quantitative as well as qualitative changes in the synthesis of mucins in goblet cells occur during the hyporegenerative and hyperregenerative phase of methotrexate-induced mucosal atrophy.

Histochemical study of mucosubstances in carcinoma of gastric remnant

Twenty patients with carcinoma of the gastric remnant after surgery for benign disease have been studied. The histologic and histochemical data on gastric mucosa surrounding the carcinoma have been compared with data from 60 biopsy samples taken from gastric stumps without carcinoma in an age-and sex-matched group. There was a high incidence of intestinal metaplasia in the gastric stumps (24 of 60); it was even higher in the cases with a carcinoma (17 of 18). Intestinal metaplasia Type III, which is closely related to the carcinoma in a stomach not surgically treated, was rare in cases of cancer in the gastric stump (1 in 18). This finding is correlated to the high frequency of the diffuse type of carcinomas that occur in the gastric stump (15 of 20), which are rarely associated with intestinal metaplasia. Therefore, identifying intestinal metaplasia types does not always point to the fact that affected patients will also be at high risk for cancer in their gastric remnant.

Histochemical procedures for the simultaneous visualization of neutral sugars and either sialic acid and its side chain O-acyl variants or O-sulphate ester. I. Methods based upon the selective periodate oxidation of sialic acids

Five new methods, based upon the selective oxidation of sialic acid residues with 0.4 mM periodic acid in approximately 1 M hydrochloric acid at 4 degree C for 1 h (PA), have been devised for the simultaneous visualization of neutral sugars and either sialic acid and its side chain O-acyl variants or O-sulphate ester. In the first of these, the selective periodate oxidation-borohydride reduction-saponification-selective periodate oxidation-Thionin Schiff-saponification-borohydride reduction-periodic acid-Schiff (PA-Bh-KOH-PA-T-KOH-Bh-PAS) technique, sialic acids with O-acyl substituents at C7, C8 or C9 (or which have two of three side chain O-acyl substituents) stain blue while neutral sugars with periodate-sensitive vicinal diols (hexose, 6-deoxyhexose, and N-acetylhexosamine) stain magenta. The second method, the saponification-selective periodate oxidation-Thionin Schiff-saponification-borohydride reduction-periodic acid-Schiff (KOH-PA-T-KOH-Bh-PAS), stains all sialic acids blue and neutral sugars magenta. In the third procedure, the selective periodate oxidation-Thionin Schiff-borohydride reduction-periodic acid-Schiff-saponification (PA-T-Bh-PAS-KOH) method, sialic acids without side chain substituents (or which have an O-acyl substituent at C7) stain blue and neutral sugars stain magenta. In the fourth method, the saponification-selective periodate oxidation-borohydride reduction-Alcian Blue pH 1.0-periodic acid-Schiff (KOH-PA-Bh-AB1.0-PAS) technique, O-sulphate esters stain aquamarine blue and neutral sugars stain magenta. In all of these techniques mixtures of the components stain in various shades of purple.(ABSTRACT TRUNCATED AT 250 WORDS)

Monoclonal antibodies to human colorectal epithelium: markers for differentiation and tumour characterization

A panel of monoclonal antibodies (MAbs) has been obtained, directed against determinants of normal human colorectal epithelium. BALB/c mice were immunized and boosted with mucosal scrapings and cell membrane preparations from normal large intestine. In one case boosting was also performed with HT29 colon carcinoma cells. Hybridoma supernatants were screened immunohistochemically on frozen sections of normal colorectal epithelium, leading to the selection of 12 MAbs which recognized determinants of the major epithelial cell lineages. These antibodies fall into two groups: group 1 antibodies react with mucus constituents, with or without other cell components; group 2 antibodies react only with non-mucus components of cells. The normal tissue distribution of the antibody panel has been characterized immunohistochemically. Three of the mucus-reactive group-1 antibodies, PR.4D4, PR.5D5 and PR.3A5, and also PR.1A3 of group 2, have a very restricted distribution. In all 4 cases, their reactivity outside the gastrointestinal tract is mainly confined to tracheal epithelium. A series of benign and malignant colorectal tumours has been studied with the antibody panel. The antibodies of group 1, and PR.1A3 from group 2, show a marked heterogeneity in their reactions with malignant cells and seem to be defining patterns of functional differentiation, independently of standard histological criteria. The reactivity of 6 colorectal carcinoma cell lines has also been assessed with the antibodies. The group-1 antibodies and PR.1A3 identify those cell lines which have retained some capacity for differentiation.

Histochemical and proliferative changes preceding the onset of spontaneous gastric adenocarcinoma in Mastomys natalensis

The histochemical and proliferative changes preceding spontaneously developing gastric adenocarcinoma were examined in Mastomys natalensis. The stomachs of 86 inbred animals from the DWZ strain were examined between 1 and 24 months of age. Two thirds of the animals had a small solitary ulcer in the middle of the lesser curvature which was observed by the first month of age. With increasing age, more and more dysplastic glands invading the submucosa were seen around the ulcer and eventually adenocarcinoma was observed after 12 month. Histochemical alterations included increased intracellular peanut lectin and Concanavalin A binding sites in the gastric pits and the development of lectin binding sites and of acid glycoproteins in the surface epithelium. Using 3H thymidine and autoradiography increased labelling and mitotic indices with extension of the progenitor area to the mucosal surface were observed around the ulcer. The coexistence of these histochemical and histokinetic alterations may represent an early sign of malignant potential in the gastric mucosa.

Intestinal metaplasia and its variants in the gastric mucosa of Portuguese subjects: a comparative analysis of biopsy and gastrectomy material

The incidence and prevalence of intestinal metaplasia (IM) of three types were investigated in 1,041 endoscopic biopsy specimens collected from patients with gastric abnormalities in 1981 and 1982. Intestinal metaplasia was classified as type I (complete), type II (incomplete, sulfomucin-negative), or type III (incomplete, sulfomucin-positive). Intestinal metaplasia, found in 244 biopsy specimens (23%), was prevalent in gastric carcinoma (65%), compared with the incidence of 18.4 per cent in benign conditions. The sulfomucin-negative types I and II were more common than type III and were present in both benign conditions (98 per cent) and carcinoma (64 per cent). In contrast, type III IM was seen in only 12 per cent of IM-positive biopsy specimens, 90 per cent of which (26 of 29) were from patients with carcinoma. The high specificity of type III IM (98 per cent) might be acceptable for screening purposes, but its sensitivity of 36 per cent for gastric carcinoma is low. Two main factors would seem to account for the low sensitivity, as shown in the comparative analysis of IM types in gastrectomy specimens and the previous biopsy specimens from 93 patients: 1) sampling and 2) the association of type III IM with gastric carcinoma of the intestinal type but not with diffuse gastric carcinoma. The data thus confirm a significant relation between incomplete sulfomucin-secreting IM (type III) and gastric carcinoma of the intestinal type (P less than 0.001). This variant of IM should be considered a risk factor, and its presence in a biopsy specimen should prompt close surveillance.

Krukenberg tumors of the ovary. Ultrastructural, histochemical and immunohistochemical studies of 15 cases

The ultrastructural, histochemical, and immunohistochemical characteristics of 12 classical signet ring cell Krukenberg tumors (CKT) and three tubular Krukenberg tumors (TKT) were evaluated and related to their possible influence on the ovarian stroma. In CKT, single signet ring cells predominated over lumen-forming cells and contained ultrastructural and histochemical characteristics similar to goblet cells in colonic and ovarian mucinous adenocarcinomas. In TKT, lumen-forming nonsecretory and secretory signet ring cells were prominent. Rare argentaffin cells were found in TKT but not in CKT. Cells in both CKT and TKT produced neutral and sialomucins. The stroma contained extracellular mucin, hypertrophied stromal fibroblasts and myofibroblasts, and in two cases stromal lutein cells with steroidogenic type ultrastructure. It appears that Krukenberg tumors are made up exclusively of intestinal type cells. Based on cell differentiation, TKT is better differentiated than CKT. Hypertrophy and hyperplasia of ovarian stromal cells may occur in response to malignant growth and/or the extracellular mucinous products of malignant cells and may play a role in the control of tumor invasiveness. None of the 15 cases were immunohistochemically positive for chorionic gonadotropin, placental lactogen, or luteinizing hormone. These hormones are suspected to be related to stromal luteinization in KT.

O-acylated sialic acid variants in mucinous tumours of the ovary

O-acylated sialic acid variants (site 8) can be demonstrated histochemically by the PB/KOH/PAS method. They are secreted by goblet cells of the lower gastrointestinal tract, by colorectal adenocarcinomas, and by their metastases. Since the metastases are positive only when the primary tumour is positive, O-acylated sialomucins can be considered to be specific markers of colorectal adenocarcinomas if identified in metastases of a tumour of unknown origin. In our histochemical study we evaluated 29 mucinous cystomas of the ovary (23 benign and 6 malignant). We found that six cases were positive to PB/KOH/PAS. The positivity was observed in a limited number of cells and only in areas which presented an intestinal type epithelium. It was also more evident in malignant cystomas than in benign ones. We therefore think that the PB/KOH/PAS positivity can not only be considered a marker of colorectal adenocarcinomas, but also of all neoplasms which originate from an intestinal epithelium or appear to an "intestinal type epithelium".

Carcinoma of the stomach in young persons

The clinical and morphologic characteristics of gastric carcinoma occurring in young persons were studied retrospectively and compared with a control group of older individuals. Immigrants from high-risk countries were found to have a higher incidence of the disease. There was a significantly longer delay in diagnosis and a significantly shorter survival when the disease in young individuals was compared with the control group. However, this difference in survival was due to a larger number of clinically advanced tumors and disappeared when the groups were matched stage for stage. As expected, diffuse carcinomas were the commonest morphologic type seen in young persons. In contrast with other studies, carcinomas in young people were found to produce larger amounts of sulphomucins than those occurring in older people. However, in the adjacent nonneoplastic epithelium, sulphomucin production and incomplete metaplasia was seen less commonly in the younger age group. These mucins' secretion patterns were more closely related to the histologic type of neoplasm than to the age of the patient.

Intestinal metaplasia in endoscopic biopsy specimens of gastric mucosa

A total of 1412 consecutive cases of endoscopic gastric biopsy, carried out over a four year period, were reviewed and specimens were examined histochemically to determine the prevalence of intestinal metaplasia and its variants. Three types were characterised: complete intestinal metaplasia and two classes of incomplete intestinal metaplasia (type IIa and type IIb) depending on the absence or presence, respectively, of sulphomucins within mucin secreting columnar cells. Type IIb intestinal metaplasia was significantly more common in patients with gastric carcinoma (p less than 0.001) and in those with dysplasia (p less than 0.001) than in patients with benign gastric pathology. No such association was found with either type I or type IIa intestinal metaplasia. In addition to those present in the columnar cells of type IIb intestinal metaplasia, sulphomucins were also commonly found in goblet cells of all three types of metaplasia. The presence of sulphomucins in goblet cells, however, was not significantly associated with gastric carcinoma or dysplasia. The significance of the different types of intestinal metaplasia in relation to the pathological findings is discussed.

Sialomucins in the assessment of dysplasia and cancer-risk patients with ulcerative colitis treated with colectomy and ileo-rectal anastomosis

The clinical notes and histology of 374 patients treated by colectomy and ileo-rectal anastomosis for ulcerative colitis were reviewed. Only those with definite diagnosis of ulcerative colitis and follow-up rectal biopsies were included (171 cases). Morphology and patterns of mucin secretion were investigated to assess whether abnormal mucin with predominance of sialomucins is a useful indicator of malignancy-risk. Carcinoma has developed in six patients and 'precancer' in seven. The results show coexistence of dysplasia and sialomucin even in the absence of inflammation in all but three biopsies; in contrast the presence of both dysplasia and normal mucin profile was found in less than 1%. A significant correlation was noted between an inflamed mucosa and the development of cancer or precancer, the presence of sialomucins and the appearance of dysplasia. Sialomucins showed a greater sensitivity in detecting cancer than dysplasia (75% versus 30%). However, dysplasia was notably more specific (94% compared with 50%), hence its greater predictive value as indicator of malignancy (50% as against 15% for a positive sialomucin result). Mucin stains on routine fixed paraffin-embedded tissue provide a simple screening method to sharpen the assessment of dysplasia and cancer-risk in patients with ulcerative colitis despite the limitations referred to above. The lack of definite evidence of dysplasia in four patients who developed malignancy without premalignant changes in the rectal biopsies emphasises the need for frequent multiple biopsies in patients with an ileo-rectal anastomosis for ulcerative colitis.

Histochemical and morphologic studies of mucosa bordering rectosigmoid carcinomas: comparisons with normal, diseased, and malignant colonic epithelium

Surgically obtained rectosigmoid mucosa ("transitional" mucosa, TM) adjacent to eight primary carcinomas was compared with diseased mucosa (DM) from eight patients without primary carcinoma and mucosa from two normal control subjects by mucin histochemical and morphologic techniques. No differences were found between TM and DM that might have suggested premalignant changes unique to TM. An excess of sialidase-susceptible sialomucins was found in both TM and DM, as was loss of the sulfomucin-sialomucin gradient usually found between normal crypts and surface cells. Increased sialic acid in TM and DM may represent a nonspecific response to injury or inflammation and has been found in other epithelia under similar circumstances. Sialidase also induced substantial reduction of periodic acid-Schiff (PAS) staining, probably due to loss of sialic acid since no other sugars were released during sialidase digestion, as determined by thin-layer chromatography analysis of post-digestion supernatants. Carcinomas generally showed more staining with PAS than with basic dyes; PAS staining was minimally reduced by diastase and sialidase but markedly reduced by phenylhydrazine interposition, suggesting that some type of neutral glycoprotein was responsible. Finally, it was found that overreliance on the high-iron diamine-Alcian blue technique as a single procedure is unwise; this procedure should be accompanied by the use of singly applied dyes, especially high-iron diamine, together with other enzymatic and staining procedures.

Mucin profiles in the mucosa adjacent to large bowel non-adenocarcinoma neoplasias

Morphological features and mucin secretion patterns were investigated in the colonic mucosa adjacent to or overlying mesenchymal or primary epithelial neoplasias, other than adenomas and adenocarcinomas. The material included 15 cases of non-adenocarcinoma tumours examined during 1978-1981. Increased sialomucins and morphological features similar to those described in the so-called 'transitional' mucosa adjacent to primary colorectal adenocarcinomas were observed in only two cases. In contrast our previous studies have demonstrated 'transitional' profiles in 98% of adenocarcinomas.

Sialomucins and carcinoembryonic antigen in the evolution of colorectal cancer

We have explored the merit of a simultaneous study of sialomucin content and carcinoembryonic antigen (CEA) expression in the identification of early malignancy in adenomas. One hundred and thirteen colorectal adenomas were investigated by histochemical and immunocytochemical techniques. We compared adenomas from 'high risk' patients having synchronous carcinoma and 'low risk' groups with incidental polyps only. Twenty-three metaplastic and eight inflammatory polyps were also included. Our data suggest that size and dysplasia are not always closely related and that synchronous adenomas seem to carry a higher malignant potential than incidental polyps irrespective of size. The degree of O-acylation of sialic acids appears to be a sensitive indicator of early malignant change: loss of O-acylation was seen in all II adenomas with highly atypical foci ('focal carcinoma') but noted in only four of the remaining polyps with lower grade dysplasia (P less than 0.005). By contrast the intensity of staining for CEA was a gradual phenomenon and showed no statistically significant increase with the onset of malignancy. Inflammatory polyps showed staining characteristics similar to normal mucosa. Metaplastic polyps, however, revealed increased expression of CEA and reduced O-acylation with increased size which may reflect a disorder of growth and differentiation. Finally, by comparing these profiles of staining with those of normal mucosa, 'transitional' mucosa adjacent to carcinoma and carcinoma, we further illustrate a progression of changes occurring in colonic mucosa in carcinogenesis.

Histochemical identification of side chain substituted O-acylated sialic acids: the PAT-KOH-Bh-PAS and the PAPT-KOH-Bh-PAS procedures

Two new methods, based on the original periodic acid-Thionin Schiff-saponification-periodic acid-Basic Fuchsin Schiff (PAT-KOH-PAS) technique of Culling et al. (1976), have been devised for the histochemical identification of side-chain O-acylated sialic acids. In the first of these, the periodic acid-Thionin Schiff-saponification-borohydride reduction-periodic acid-Basic Fuchsin Schiff (PAT-KOH-Bh-PAS) procedure, the specificity of the original PAT-KOH-PAS technique was improved by: (a) extending, when necessary, the initial period of periodate oxidation, (b) increasing the period of exposure to Thionin Schiff reagent from 30 min to 4 h, (c) using a Thionin Schiff reagent prepared by a different method, (d) interposing a borohydride reduction step between the saponification and PAS steps and, (e) extending the period of oxidation in the final PAS step from 10 to 30 min. In the second procedure, the periodic acid-phenylhydrazine-Thionin Schiff-borohydride reduction-periodic acid-Basic Fuchsin Schiff (PAPT-KOH-Bh-PAS), based on the periodic acid-phenylhydrazine-Schiff (PAPS) technique of Spicer (1961), blue Thionin Schiff staining was confined to sialic acid residues with oxidizable side chain vicinal diols by interposing a treatment with 0.5% (w/v) aqueous phenylhydrazine hydrochloride for 2 h at room temperature between the initial periodic acid oxidation and the Thionin Schiff steps of the PAT-KOH-Bh-PAS procedure. These procedures are discussed within the general framework of the methods available for the histochemical identification of side-chain O-acylated sialic acids.

Cancer surveillance after ureterosigmoidostomy: colonic microscopic changes

Ureterosigmoidostomy (U-S) is a procedure for diversion of the urinary stream. U-S is associated with a manyfold-increased risk for subsequent development of colonic carcinoma close to the sites of ureteral entry into the sigmoid colon. A surveillance program for colonic carcinomas in U-S patients includes colonoscopic examination of the colon to at least 60 cm and random biopsies of the sigmoid colon distal to the ureteral orifices. In eight patients, a change from sulphomucin to a variable admixture with sialomucin was found in the histologically unremarkable colonic mucosae. When the urinary stream was shunted away from the U-S site in two patients, the mucosal mucin was composed of sulphomucin which is present in normal sigmoid colons. The effect of urine admixed with feces in the sigmoid colon is nonspecific as judged by alterations of the mucosal mucin composition. The U-S patient deserves periodic examinations to detect colonic carcinoma but the histological examination of colonoscopically unremarkable mucosae is not currently contributory toward this surveillance effort.

Gastric cancer: problems in histogenesis

Intestinal metaplasia in the mucosa adjacent to a gastric carcinoma suggests that some carcinomas of the stomach might arise from metaplastic mucosa, as well as the existence of a gastric cancer with morphological features resembling intestinal mucosa. In this study, the extent of intestinal metaplasia of adjacent mucosa, the type of intestinal metaplasia (complete or incomplete), the degree of tumour differentiation, the type and quantity of mucins secreted by neoplastic cells and morphological features of the tumours were evaluated in 59 cases of gastric carcinoma. An analysis of the findings suggests that a carcinoma may arise in the stomach with features of association with incomplete metaplasia and histochemical and histological patterns which mimic carcinomas of the large intestine.

Histochemical characterization of different types of intestinal metaplasia in gastric mucosa

The histochemical patterns of mucosubstances in 1.010 intestinal metaplasia (IM) foci in stomachs removed during surgery for benign ulcer and carcinoma has been studied. Two kinds of IM were characterized: the complete and the incomplete types, with the first one subdivided in Small intestine Type I, Small intestine Type II, and Colonic type, based on their similarity of mucosubstances, with those found in normal small intestine and colon, and the second one divided in two groups, depending on the presence or absence of sulfomucins. The incomplete type with sulfomucins was significantly more frequent in patients with carcinoma than in benign ulcer cases (P less than 0.001) as well as, in stomachs bearing intestinal type of carcinoma than in stomachs with diffuse type of carcinoma (P less than 0.005). The significance of the different types of IM, in relation to the gastric pathologic findings is discussed.

Adenosquamous carcinoma of the stomach: histological, histochemical and ultrastructural observations

The histochemical and ultrastructural features of an adenosquamous carcinoma of the stomach have been studied. Both the adenomatous and the squamous component of the tumour showed malignant characteristics. Elements which were considered as undifferentiated cells on light microscopy showed ultrastructural features of poorly differentiated squamous cells. No intermediate cells, sharing squamous and glandular aspects, were found by electron microscopical examination. The adenomatous component exhibited histochemical and ultrastructural features of the intestinal type of gastric carcinoma and the mucosa surrounding the tumour showed a colonic type of intestinal metaplasia. A possible histogenesis from a totipotential undifferentiated cell is considered.

Neutral mucin content of gastric carcinomas as a diagnostic aid in the identification of secondary deposits

A simple quantitative method used in conjunction with the diastase digestion-Alcian blue-PAS (D-AB-PAS) technique was employed in a retrospective study of 135 gastrectomy carcinomas, and in a range of 57 unrelated metastatic adenocarcinoma cases of confirmed origin, to determine what proportion of malignant cells/glands contained neutral mucin only, as against acidic mucin or mixtures of both acid and neutral types. Fifty of the gastrectomy cases (37%) showed a high neutral mucin content of 71% or more, this feature being more evident in the diffuse (D) type of tumour. The metastatic adenocarcinoma cases comprised 35 of non-gastric origin of which eight (23%) had a high neutral mucin content of 71% or more, compared to 10 out of 22 cases of gastric origin (45%) having a neutral mucin content of 71% or more. It was felt significant that seven out of these 10 gastric cases were of the D type of tumour. The secondary adenocarcinoma of uncertain (unconfirmed) origin contained a group of cases with deposits of probable gastric origin of which more than half showed a high proportion of cells which contained neutral mucin only. The helpfulness of these findings is discussed.

Mucin secretion in inflammatory bowel disease: correlation with disease activity and dysplasia

When rectal biopsies from 65 patients with ulcerative colitis and 20 patients with Crohn's disease was stained for mucins, an abnormal pattern (excess of sialomucins) was seen in about half of them. This is in contrast with 65 cases of non-specific proctitis where the mucin pattern of rectal biopsies was normal in all except one case. The abnormal mucin secretion in patients with ulcerative colitis was apparently related to the activity, duration, and extent of the disease. All biopsies with dysplasia showed predominant sialomucin staining except one. All biopsies showing sialomucins during remission also had dysplasia, while during active disease a number of biopsies had increased sialomucins without the evidence of dysplasia. It is not known if such cases will subsequently develop morphological atypia.

Tumor markers in carcinoma and premalignant states of the stomach in humans

Tissue sections taken from areas of carcinoma, areas of intestinal metaplasia in stomachs bearing carcinoma are areas of intestinal metaplasia in stomachs showing atrophic gastritis only were examined for eight markers: a tumour-derived colon-specific antigen (tCSA), carcinoembryonic antigen (CEA), alpha-fetoprotein (AFP), pregnancy-specific beta-glycoprotein 1 (SP1), human placental lactogen (HPL), human beta chorionic gonadotrophin (beta-HCG), transferrin (TF) and ferritin (FE). In terms of the number of markers demonstrated in each of the three categories, there is a close similarity between the cells of adenocarcinoma and cells of intestinal metaplasia in cases of cancer, but not to similar metaplastic cells in atrophic gastritis cases. In addition, it appears that the presence of tCSA and SP1 is closely linked to carcinoma, though only approximately half of such cases contain these markers. It would also appear that there are two types of morphologically identical intestinal metaplasia, one related to cancer, the other not. No difference was found between so-called intestinal type and diffuse-type carcinomas.

The mucin profiles of normal gastric mucosa, intestinal metaplasia and its variants and gastric carcinoma

Human gastrectomy specimens, including 48 carcinomas and 25 selected benign cases showing extensive intestinal metaplasia (IM), were examined in detail histologically and histochemically. IM was classified into complete (type I), incomplete without sulphomucins (type IIA) and incomplete with sulphomucins (type IIB). Type IIB was associated with 'intestinal' but not 'diffuse' cancers (P less than 0.01) or benign lesions (P less than 0.01). The mucin profiles of IIB IM were similar to 'intestinal' cancers with sulphomucins predominating over N-acetylsialomucins. O-acetylsialomucins were not seen in IIB IM or tumours but were observed in complete or type I IM. These findings suggest a histogenic link between incomplete IM secreting sulphomucins (or 'colonic' metaplasia) and 'intestinal' cancers of the human stomach.