Pathologic Features of Hereditary Non-Polyposis Colorectal Cancer

In hereditary non-polyposis colorectal cancer (HNPCC) patients, the cancer frequently arises in the proximal colon and is often multiple (synchronous or metachronous). Pathologic differences seem to exist between hereditary and sporadic large bowel cancer, but the data are not uniform. Many authors reported that the following histologic features are often present in HNPCC: 1) mucinous histotype, 2) poorly differentiated tumors, 3) presence of peritumoral lymphocytic infiltrate, with Crohn's-like lymphoid reaction. Such features have also been found in apparently sporadic colorectal cancer with, but not in sporadic colorectal cancer without DNA replication errors. Many studies have suggested that adenoma plays a main role in HNPCC carcinogenesis, and that the “adenoma-carcinoma sequence” may be the pathway to cancer in HNPCC as in sporadic colorectal cancer. Moreover, HNPCC adenomas show an early onset, villous component, high-grade dysplasia, and positivity for DNA replication errors more frequently than sporadic adenomas. Such data suggest that the adenoma-carcinoma sequence is accelerated in HNPCC and that surveillance in these patients should therefore be strict to avoid cancer development.

Osteogenic Sarcoma of the Breast. A Case Report

A case of primary osteogenic sarcoma of the breast is reported. It should be distinguished from carcinoma with extensive osseous metaplasia. The results of light and electron microscopy including an immunohistochemical study are presented. Immunohistochemical and ultrastructural studies proved that the lesion, in the absence of epithelial differentiation, was a primary osteogenic sarcoma of the breast rather than a carcinoma with extensive osseous metaplasia. Diagnosis may be delayed because the tumor is confused clinically and mammographically with a calcific fibroadenoma.

Lack of Prognostic Value of p53 Protein Expression in Node-Negative Breast Cancer

Aims and background

The association of p53 protein accumulation and prognosis in node-negative breast cancer patients has been alternately demonstrated and denied in literature reports, and opinions on the use of p53 expression as an indicator of high risk of recurrence and as a guide for adjuvant therapy are controversial.

Study design

The association of p53 protein accumulation with prognosis was retrospectively evaluated in a series of 221 node-negative breast cancer patients treated with surgery alone and followed up for a minimum of 10 years. p53 accumulation was determined by immunohistochemistry on archive material, and classified into four grades of increasing immunostaining.

Results

No association was observed between p53 and age or pT category, whereas a significant association with nuclear grade was found (P = 0.0014). Univariate and multivariate analysis of 10-yr disease-free and overall survival showed a significant and independent prognostic association for tumor size (pT category) and nuclear grading but not for p53 expression, whatever grade grouping was used.

Conclusions

We did not find any evidence supporting the use of p53 immunostaining in current practice as an independent prognostic indicator or as a discriminant factor for adjuvant treatment of node-negative breast cancer patients.

Posterior wall as atypical localization of left atrial myxoma : Diagnosis and management

Atrial myxomas are the most common benign cardiac neoplasms. Although the majority occur in the left atrium (LA) and are attached to the interatrial septum (75-80 % of cases), they can arise from any part of the LA and the cardiac chambers. We report the case of a 65-year-old woman who presented with features of worsening dyspnea and persistent headache. During transthoracic echocardiography, a suspected cardiac myxoma was found arising from the posterior wall of the LA.

Serrated and microtubular colorectal adenomas in Italian patients. A 5-year survey

Colorectal adenomas from 1552 Italian patients were histologically classified into tubular (TAs), tubulo-villous (TVAs), villous (VAs), serrated (SAs) and microtubular (MTAs). The purpose was to compare the results to those in 3135 colorectal adenomas from Swedish patients. Of the 1552 adenomas, 827 (53%) were TAs, 352 (23%) TVAs, 196 (12%) VAs, 102 (7%), SAs and 14 (0.9%) MTAs. The remaining 61 (4%) were of combined phenotypes (COMBAs). The percentage of VA (considered as the most important dysplastic precursor of colorectal cancer) was higher in Florence than in Stockholm. Notably, the incidence of colorectal cancer in males was also higher in Florence (78.6/10(5)) than in Stockholm (57.2/10(5)). Notwithstanding, the highest rate of submucosal invasion (7%) was found among SAs. The diameter of the largest section was used to define the size of the largest adenoma in individual patients. Of the 1380 neoplasias measuring < or =12 mm, only 0.9% (n=13) had invasive carcinomas, but as many as 8.1% (n=14) of the 172 neoplasias measuring > or =13 mm. SAs and MTAs are special adenoma phenotypes with particular morphological and cell proliferative attributes at variance from those of TAs, VAs or TVAs. In the light of the present results, it is proposed that SAs and MTAs are included in future reports of colorectal adenomas in order to compare their frequency worldwide.

Gastric carcinomas of intestinal type concur with distant changes in the gastric mucosa. A multicenter study in the Atlantic basin

Population studies in the Pacific Basin showed that gastric carcinomas of intestinal type often concur with distant mucosal changes (DMCs). In the present work, the presence of DMCs was investigated in populations dwelling in the Atlantic Basin. A total of 1737 gastrectomy specimens were reviewed: 627 in New York, 435 in Reykjavik, 198 in Buenos Aires, 186 in Florence, 174 in London and the remaining 117 in Stockholm. A total of 17,282 sections were carefully scrutinized. The following DMCs were investigated: intramucosal glandular cysts, gastric cells with ciliated metaplasia, with large or small mucus negative vacuoles, and extensive intestinal metaplasia (IM). The highest frequencies of DMCs were found in Florence for specimens with intestinal type carcinoma: 41.3% had intramucosal cysts, 22.4% had cells with ciliated metaplasia, 12.9% cells with large vacuoles, and 50.9% had high IM. The highest frequency of gastric cells with small vacuoles was recorded in New York (9.1%), also in specimens with intestinal type carcinoma. Significantly lower DMCs percentages were found in specimens with carcinomas of diffuse type, and miscellaneous gastric diseases. The occurrence of DMCs was not influenced to a significant degree by the number of sections available per gastrectomy. Since environmental factors trigger the evolution of intestinal type carcinomas and as DMCs also occurred in specimens without carcinoma-although at a significantly lower rate--it is conceivable that DMCs are also evoked by environmental factors (before a gastric carcinoma ensues). DMCs were found in specimens having intestinal carcinomas either in the cardia, the corpus or the antrum. Thus, DMCs seem to provide the adequate "soil" for the development of gastric carcinomas of intestinal type, independently of the future localization of that tumor in the stomach.

Ultrastructural features of solid/trabecular areas in differentiated thyroid carcinoma

The presence of areas exhibiting a solid/trabecular pattern of growth within an otherwise differentiated thyroid carcinoma represents a source of controversy as regards its proper classification and biologic and prognostic significance. The aim of the current study was to investigate the ultrastructural features of solid/trabecular areas in differentiated thyroid carcinoma and to compare those features with the submicroscopic profile of differentiated, poorly differentiated (insular), and undifferentiated (anaplastic) variants of thyroid cancer. The study series included differentiated carcinoma with solid/trabecular areas (3 cases), conventional papillary carcinoma (4 cases), follicular variant of papillary carcinoma (4 cases), poorly differentiated (insular) carcinoma (3 cases), and undifferentiated (anaplastic) carcinoma (3 cases). It was found that the solid/trabecular areas in differentiated carcinoma and poorly differentiated (insular) carcinoma share similar ultrastructural features and overall retain, even if attenuated, many of the submicroscopic attributes of differentiated carcinomas. In particular, nests of neoplastic cells were observed showing a highly developed cytosecretory apparatus and the presence of numerous abortive/rudimentary follicles, and intercellular and intracellular (intracytoplasmic) lumina/canaliculi of variable morphology. The study supports the hypothesis that the solid/trabecular areas do not merely represent an architectural pattern but rather should be regarded as the expression of a process of reduced differentiation similar to that of poorly differentiated (insular) carcinoma.

Prognostic significance of microsatellite instability in sporadic mucinous colorectal cancers

We investigated the prognostic significance of microsatellite instability (MI) in 50 consecutive patients with sporadic mucinous colorectal cancer who had undergone only surgery. We evaluated MI and the pathological features with a possible prognostic value for each tumor, and the effect of the examined parameters on patients' outcome was statistically analyzed (univariate and multivariate analysis). All patients were followed-up for a minimum of 72 months or until death; in evaluating survival, only deaths of colorectal cancer were considered. DNA extracted from tumor sections and the corresponding normal tissue was analyzed by polymerase chain reaction at six microsatellite loci: D2S123, D3S1611, D3S49, D5S107, BAT26, BAT40. Alterations at two or more loci were detected in 36% of cases (MI+ tumors). MI+ and MI- cancers differed significantly in the pattern of growth, and most MI+ tumors showed an expanding type of growth (72.2%, P = .005). At univariate analysis, improved survival rate was significantly associated with MI, as well as with the following parameters: expanding cancer growth, Dukes stage, and absence of venous invasion. Nevertheless, at multivariate analysis, only the pattern of cancer growth and Dukes stage were independent prognostic factors, whereas the effect on survival of MI and venous invasion was found to be negligible. In our study, MI+ and MI- cancers differ only on the pattern of growth; therefore, our data suggest that the better survival rate in mucinous cancers with genomic instability is strictly related to their less aggressive type of growth.

Expression of transforming growth factor beta isoforms in osteosarcoma variants: association of TGF beta 1 with high-grade osteosarcomas

Studies on osteosarcoma cell lines point to the potential importance of transforming growth factor beta (TGF beta) as an autocrine factor which controls the growth of human osteosarcomas. To define further the role of TGF beta isoforms in these neoplasms, a series of 27 osteosarcomas was studied using immunohistochemical, mRNA in situ hybridization, and reverse transcriptase-polymerase chain reaction (RT-PCR) techniques. All 14 central high-grade osteosarcomas, two telangiectatic osteosarcomas, and one high-grade surface osteosarcoma showed cytoplasmic immunoreactivity for TGF beta 1, -2, and -3. The expression of TGF beta 1 was moderate or diffuse in 14 cases (82.3 per cent), while low expression was detected in only three cases (17.7 per cent). For TGF beta 2 and -3, only moderate or diffuse staining was observed. Low-grade parosteal and periosteal osteosarcomas showed low or undetectable levels of TGF beta 1, while TGF beta 2 and -3 were moderately or diffusely expressed. Finally, three dedifferentiated parosteal osteosarcomas were diffusely positive for TGF beta 1, -2, and -3 in the high-grade component, while in the low-grade component, available for analysis in two of these cases, TGF beta 1 was demonstrated in a few neoplastic cells, and TGF beta 2 and -3 maintained a diffuse distribution. Statistical analysis of these data showed that high-grade osteosarcomas had a significantly higher expression of TGF beta 1 than low-grade osteosarcomas, while levels of TGF beta 2 and -3 were comparable in the two groups (p < 0.001; p = 0.3; p = 0.3, respectively; Fisher's exact test). Similarly, mRNA levels of TGF beta 1 detected by in situ hybridization were significantly higher (p = 0.04, Fisher's exact test) in high-grade osteosarcoma variants, while no differences were found for TGF beta 2 and -3 mRNA (p = 1.0; p = 0.2, respectively; Fisher's exact test). In addition, mRNA analysis performed by RT-PCR in seven cases (five high-grade and two low-grade osteosarcomas) confirmed the presence of high levels of TGF beta 1 in high-grade osteosarcomas, while low-grade tumours had low or absent mRNA expression. In conclusion, this positive association suggests that TGF beta 1 may be involved in determining the aggressive clinical behaviour of high-grade osteosarcomas.

Immunohistochemical detection of c-fos and c-jun expression in osseous and cartilaginous tumours of the skeleton

The products of c-fos and c-jun proto-oncogenes form the heterodimeric complex AP-1 (activator protein 1), which play an important part in the control of bone cell proliferation and differentiation and in the development of bone tumours. We examined the expression of c-fos and c-jun in a series of 52 primary skeletal neoplasms, using an immunohistochemical method on formalin-fixed, paraffin-embedded sections. The expression of c-fos and c-jun was restricted to bone-forming lesions, while cartilaginous tumours were devoid of immunoreactivity. In benign osteoblastic lesions moderate c-fos and c-jun expression was found in 2 cases (18.1%). The highest levels of c-fos and c-jun expression were detected in high-grade central osteosarcomas (7 of 15 cases with moderate/diffuse expression) while 1 telangiectatic osteosarcoma, 2 low-grade central osteosarcomas, 1 low-grade periosteal osteosarcoma and 7 low-grade parosteal osteosarcomas were either negative or had low expression. The high-grade component of a dedifferentiated parosteal osteosarcoma showed diffuse immunoreactivity for both oncoproteins. Comparison of c-fos and c-jun expression by histological grade showed that high-grade osteosarcomas had a significantly higher expression of both oncoproteins than did low-grade osteosarcomas (P = 0.01, Fisher's exact test). Thus, c-fos and c-jun overexpression may be implicated in the development of high-grade osteosarcomas, but they appear to have little or no relevance for the development of low-grade osteosarcomas and cartilaginous skeletal neoplasms.

Effects of tumor necrosis factor-alpha and interleukin-6 on fluid-phase permeability and ammonia diffusion in CNS-derived endothelial cells

BACKGROUND

Proinflammatory cytokines tumor necrosis factor-alpha (TNF-alpha) and interleukin-6 (IL-6) play an important role in the blood-brain barrier breakdown present in several neurological diseases including multiple sclerosis and AIDS. However, the specific effects of these cytokines on central nervous system-derived endothelial cells (CNS-EC) is not fully understood. In this study the effects of TNF-alpha and IL-6 were tested on different permeability mechanisms of CNS-EC.

METHODS

Central nervous system endothelial cells were isolated from human brain and retina and cultured in vitro in a transwell system. Fluid-phase endocytosis and transcytosis, absorptive-mediated endocytosis, and ammonia diffusion were measured with specific methods. Endothelial cells were studied with electron microscopy for the ultrastructural effects of cytokine stimulation.

RESULTS

Fluid-phase endocytosis and transcytosis were significantly increased by TNF-alpha and IL-6. This effect was dose dependent and reversible. The ammonia diffusion rate was also significantly increased by TNF-alpha. Absorptive-mediated endocytosis was not enhanced by TNF-alpha. Ultrastructural analysis of cytokine-treated CNS-EC confirmed the alterations in permeability showing an increase in endocytotic activity and a decrease in tight junctions.

CONCLUSIONS

The proinflammatory cytokines IL-6 and TNF-alpha induce specific changes in the morphology and permeability of CNS-EC. These alterations can be important in many diseases characterized by increased cytokine production.

Primary signet-ring cell carcinoma of the colon and rectum

PURPOSE

Colorectal signet-ring cell carcinoma (SRCC) is uncommon; discordant data have been previously reported about clinicopathologic features. Thirty-four cases of primary colorectal SRCC were retrospectively reviewed to clarify controversies.

METHODS

Primary colorectal SRCC was diagnosed when the following criteria were satisfied: 1) the tumor was primary; 2) histologic material was adequate; 3) signet-ring cell represented more than 50 percent of the cancer.

RESULTS

We identified 34 cases (1.1 percent) of 2,995 consecutive large bowel cancers collected at the Institute of Anatomic Pathology of Florence between 1985 and 1993. Patients ranged in age from 31 to 89 (mean, 63.5; median, 65) years; 19 were male, and 15 were female (male:female = 1.3:1). Fifteen tumors were located in the proximal colon, 11 in the rectum, and 8 in the distal colon. The gross shape was infiltrative in 24 cases and exophytic in 10; only 6 cases (17.6 percent) showed features of linitis plastica. Most cancers (61.8 percent) were Stage C, 29.4 percent were Stage B, and distant metastases were present in only three cases (8.8 percent). No Stage A case was found. Prognosis was extremely poor, and overall five-year survival rate was 9.1 percent. Survival was influenced significantly by tumor stage (P < 0.01).

CONCLUSIONS

Comparison of our data with the literature showed many differences that could be related to different applied diagnostic criteria. We underlined the importance of histology as reproducible criterion for diagnosis of primary colorectal SRCC.

Mesothelioma as a risk indicator of asbestos exposure: the role of the pathologist

Malignant mesothelioma is an uncommon tumour, which has become an important epidemiological marker for exposure to asbestos. This tumour is characterised by a wide range of microscopic features which may be classified in three histologic patterns: epithelial, mesenchimal and mixed or biphasic. Histochemical staining is often necessary to distinguish mesothelioma from carcinoma. As regards immunohistochemistry, only the use of a combination of antibodies significantly decreases the risk of false-negative results. Analytic electron microscopy techniques may also be useful, permitting the evaluation of the cumulative fiber burden in the target organ.

Accuracy and reliability of frozen section diagnosis in a series of 672 nonpalpable breast lesions

Frozen section (FS) diagnosis was routinely performed in a large series of nonpalpable breast lesions from 1977 through 1991. The original FS diagnoses of 672 patients were classified in four categories (1 = benign lesion, 2 = in situ carcinoma, 3 = invasive carcinoma, 4 = deferred diagnosis) and compared with the diagnoses obtained at review of the permanent paraffin sections to estimate the accuracy of FS. A review of the mammographic pattern of the lesion was also performed. Frozen section diagnostic conclusion was deferred to permanent paraffin sections in only 22 cases (3.3%). Benign or malignant (grouping in situ and invasive carcinomas) FS diagnoses were accurate in 623 of 650 cases (95.8%). Overall, the prevalence of malignant lesions was 44.8% with a benign/malignant ratio of 1.2. The diagnosis was modified on the basis of permanent sections in 27 cases (4.2%) with three false positives and 24 false negatives. Sensitivity and specificity of FS diagnoses were 91.7 and 99.2%, respectively. When the comparison between FS and histologic diagnoses was analyzed according to the mammographic pattern, sensitivity among patients with microcalcifications as the only alteration was lower (88.8%) than among patients with opacities (94.9%). On the basis of these results, FS is to be considered a feasible and reliable diagnostic procedure in nonpalpable breast lesions, particularly in cases excised because of a mammographic opacity that is identifiable on gross examination of the surgical specimen.

[Intraoperative histological study of nonpalpable lesions of the breast]

The intraoperative frozen section technique has proven to be valid and accurate in the diagnosis of palpable breast lesions, while its use in non-palpable lesions of the breast has been recently discussed. In order to estimate the accuracy of frozen section technique in non-palpable breast lesions we reviewed our series of 672 cases of non-palpable lesions examined intraoperatively between January 1977 and December 1991. Frozen section diagnoses were compared with diagnoses obtained at review of the permanent paraffin sections. A review of the mammographic pattern of each lesion was also carried out. Frozen section diagnosis was replaced by permanent paraffin sections in 22 cases (3.3%). Benign or malignant (in situ and invasive carcinomas) frozen section diagnoses were accurate in 623 of 650 cases (95.8%). Frozen section diagnosis was modified on the basis of permanent sections in 27 cases (4.2%), with 3 false positives and 24 false negatives. Sensitivity and specificity of frozen section technique were 91.7% and 99.2%, respectively. Comparing frozen section and definitive diagnosis according to the mammographic pattern, sensitivity was lower in patients with microcalcifications as the only alteration (88.8%) compared with patients with opacities (94.9%). On the basis of our results the frozen section technique in non-palpable breast lesions is to be considered a valid and reliable diagnostic procedure, particularly in lesions detectable at mammography as an opacity and identifiable on gross examination of the surgical specimen.

Expression of retinoblastoma protein in human breast cancer: an immunohistochemical study

The product of the human retinoblastoma gene (pRb) is a nuclear phosphoprotein that is thought to function as a tumor suppressor. Heterogeneous expression of the Rb gene product contributes to the genesis of a diverse group of human neoplasma such as breast, prostate, small cell lung, bladder carcinomas and leukemia. The clinical importance of Rb function demands a reproducible Rb immunohistochemical assay to distinguish Rb+ from Rb- tumor cells. We report an immunohistochemical study to detect Rb protein in a series of 50 invasive breast cancers. Our results support the hypothesis that the Rb gene functions as both a cell growth factor and a tumor suppressor.

Prognostic value of proliferating cell nuclear antigen in lymph node-negative breast cancer patients

BACKGROUND

The prognostic value of proliferating cell nuclear antigen (PCNA) has been demonstrated in recent studies of human tumors including breast cancer.

METHODS

PCNA immunoreactivity was assessed retrospectively in a consecutive series of 173 lymph node-negative primary breast cancer cases. The PCNA grade was determined according to estimated quartiles of nuclear immunostaining, and its association to disease-free and overall survival was studied.

RESULTS

PCNA grade was associated significantly with nuclear grade. On univariate analysis, PCNA grade was associated significantly with both 5-year relapse-free survival rate (Grades 1-2 = 78%; Grades 3-4 = 52%; P = 0.0117) and overall survival. On multivariate analysis, T category and PCNA were associated independently and significantly with both relapse-free and overall survival. Nevertheless, the magnitude of the association of PCNA grade to prognosis was low (relative risk of recurrence in patients with PCNA Grades 3-4 versus Grades 1-2 = 2.13), and only 24% of all relapses or 28.8% of all cancer deaths observed at 5 years occurred in patients with PCNA Grades 3-4.

CONCLUSIONS

The predictive value of the relationship of PCNA grade to prognosis was too low to be of value as an independent prognostic indicator.

Prognostic significance of c-erbB-2 expression in node negative breast cancer

The prognostic value of c-erbB-2 oncogene expression was studied retrospectively in a consecutive series of 230 node negative breast cancers, followed-up for at least 7 years after primary treatment. The expression of c-erbB-2 oncoprotein was determined on formalin-fixed paraffin-embedded tissue, using a monoclonal anti-c-erbB-2 antibody by the avidin-biotin immunoperoxidase method. Positive immunostaining was observed in 20.9% of cases, whereas strong diffuse positivity was recorded only in 8.7% of cases. C-erbB-2 gene product showed no association to T category or nuclear grade. A significant association of c-erbB-2 expression to prognosis was observed only for cases showing a strong diffuse immunostaining, but such an association was no longer statistically significant at multivariate analysis adjusting for other prognostic factors such as T category and nuclear grading. C-erbB-2 expression is of no value to predict the clinical course of node negative patients in the current practice.

Prognostic significance of accessory cells and lymphocytes in nasopharyngeal carcinoma

Forty-five consecutive biopsy specimens of nasopharyngeal carcinoma (NPC) and 10 biopsies of healthy nasopharyngeal mucosa obtained from non-cancer patients were investigated by immunohistochemical methods. Monoclonal (B2, T1) and policlonal antibodies (against S-100 protein and lysozyme) with reference to infiltrating lymphocytes and accessory cells (monocytic/macrophagic and dendritic cells) were used. Variable population densities of dendritic cells (S100+) were demonstrated in 22 out of the 45 cases (49%) of NPC; the distribution of these cells was typically within the cancer nests. Monocytic/macrophagic cells (Lys+) were found along the tumor margins and interspersed among the tumor cells in 14 out of 45 (31%) cases. No significant statistical correlation between density of accessory cells and histological type of NPC (classified according to Micheau criteria) was found. Cases with a moderate to marked density of dendritic and monocytic/macrophagic cells survived longer than those with a slight one (mean survival of 63%, 67% and 29%, 27% respectively). In NPC tissues T-lymphocyte infiltration was prevalent. In contrast, B cells were numerous and T cells rare in normal control tissues. The intensity of T-cell infiltration was significantly high in cases with a marked density of S-100+ cells, according to the ability of these cells to present antigens to sensitized T-cells. This study suggests a prognostic significance for reactive cells infiltrating NPC, which means longer survival for cases associated with marked infiltration density of accessory cells.

Cingulin, a specific protein component of tight junctions, is expressed in normal and neoplastic human epithelial tissues

Cingulin is a 140-kd protein localized on the cytoplasmic face of avian tight junctions. The expression of cingulin in human normal and neoplastic colonic tissue has been investigated with an antiserum against chicken cingulin. Human cingulin shares its apparent molecular mass and localization with avian cingulin. In normal colonic epithelium, villous adenomas, and differentiated adenocarcinomas, cingulin staining is observed in the junctional region of the polarized cells lining the surface, the crypts, and the glandular lumina. In poorly differentiated adenocarcinomas, labeling also is observed at the interface between cancer tissue and stroma, or in clumps of malignant cells, forming a pattern that highlights the presence of small, compressed lumina. The cingulin content of four adenocarcinomas, estimated by immunoblotting and densitometry, was higher than that of the normal tissue (150% to 230%). Cingulin was detected in a metastasis from a colon adenocarcinoma but not in nonepithelial tissues and neoplasias, suggesting that cingulin may be a useful marker in the characterization of colonic and probably other epithelial neoplasias.

Gastric cancer in a high-risk area in Italy. Histopathologic patterns according to Lauren's classification

Two thousand five hundred forty cases (1628 males and 912 females) of primary gastric cancer (GC) histologically diagnosed in gastroscopic biopsy or resected specimens, occurring from 1973 to 1982 in a high risk area in Italy (Florence), were reviewed. According to Lauren's criteria, 1587 (62.5%) were classified as intestinal type, 624 (24.6%) as diffuse type and 329 (12.9%) as mixed unclassified. The intestinal type is more frequent in males and increases in both sexes with advancing age; conversely for the diffuse type. In the two 5-year periods (1973-1977 and 1978-1982) the intestinal type shows a reduction over time more evident in females than in males, in contrast to the increasing trend for the diffuse type. In males, the distribution of Lauren's histologic types is stable over time for resected specimens, whereas there is a significant reduction of intestinal type for biopsy specimens. In females, both for resected and biopsy specimens there is a reduction of the intestinal type and an increase of the diffuse type from the first to the second period. For a subgroup of 297 subjects two different specimens were available (gastroscopic biopsy and surgical); sensitivity and positive predictive value, for biopsy specimen as compared with the resected one, in the diagnosis for Lauren's histologic types were calculated. An excess of diagnoses in the mixed/unclassified category for biopsy material was evident (positive predictive value = 44.3%). However, for the two main histologic types, the biopsy appears a quite reliable indicator of the final diagnosis on surgical material (intestinal: ppv = 88.6%; Diffuse: ppv = 87.0%). The study supports the hypothesis that the reduction in GC mortality in the Province of Florence in recent years may be associated with a moderate reduction in the frequency of the intestinal type.

Gastric cancer in a high-risk area in Italy. Histopathologic patterns according to Lauren's classification

Two thousand five hundred forty cases (1628 males and 912 females) of primary gastric cancer (GC) histologically diagnosed in gastroscopic biopsy or resected specimens, occurring from 1973 to 1982 in a high risk area in Italy (Florence), were reviewed. According to Lauren's criteria, 1587 (62.5%) were classified as intestinal type, 624 (24.6%) as diffuse type and 329 (12.9%) as mixed unclassified. The intestinal type is more frequent in males and increases in both sexes with advancing age; conversely for the diffuse type. In the two 5-year periods (1973-1977 and 1978-1982) the intestinal type shows a reduction over time more evident in females than in males, in contrast to the increasing trend for the diffuse type. In males, the distribution of Lauren's histologic types is stable over time for resected specimens, whereas there is a significant reduction of intestinal type for biopsy specimens. In females, both for resected and biopsy specimens there is a reduction of the intestinal type and an increase of the diffuse type from the first to the second period. For a subgroup of 297 subjects two different specimens were available (gastroscopic biopsy and surgical); sensitivity and positive predictive value, for biopsy specimen as compared with the resected one, in the diagnosis for Lauren's histologic types were calculated. An excess of diagnoses in the mixed/unclassified category for biopsy material was evident (positive predictive value = 44.3%). However, for the two main histologic types, the biopsy appears a quite reliable indicator of the final diagnosis on surgical material (intestinal: ppv = 88.6%; Diffuse: ppv = 87.0%). The study supports the hypothesis that the reduction in GC mortality in the Province of Florence in recent years may be associated with a moderate reduction in the frequency of the intestinal type.

Morphological precursors of hepatocellular carcinoma: a morphometrical analysis

Morphometrical analysis of different types of liver cells was performed in cases of chronic active hepatitis (CAH), liver cirrhosis (LC), and hepatocellular carcinoma (HCC). The area and a form factor (form AR) of nuclei and cytoplasms were determined, and the nucleo-cytoplasmic ratio (N/C) was calculated in normal hepatocytes, HBsAg-positive cells, large dysplastic cells, cancer cells and in a liver cell population identifiable as "small dysplastic cells" (small cells). The nucleo-cytoplasmic ratio of the small cells and of the neoplastic cells was roughly the same and the highest. Large dysplastic cells showed a small nucleo-cytoplasmic ratio, almost comparable with that of normal hepatocytes and similar to that of HBsAg-positive cells. Since cellular precursors of liver cancer are expected to have a nucleo-cytoplasmic ratio similar to that of neoplastic cells, our morphometrical evaluation indicates small cells as the true precancerous cells; liver cell dysplasia (large dysplastic cells), as described by Anthony et al., should not be considered as a true preneoplastic change.

Papillary carcinoma of the thyroid. A clinicopathologic study of 241 cases treated at the University of Florence, Italy

A clinicopathologic study of 241 cases of papillary thyroid carcinoma treated at the University of Florence Medical School, Florence, Italy is presented. The features of greatest prognostic value were patient's age at presentation, small tumor size, total encapsulation, extrathyroid extension, multicentricity, and presence of distant metastases. The prognosis of the disease was not influenced by the pattern of tumor growth, presence of solid areas, initial presence or subsequent development of cervical lymph node metastases, type of initial thyroid operation, performance of neck dissection, or prophylactic administration of radioactive iodine. It is concluded that conservative thyroid surgery in the form of lobectomy, without neck dissection or prophylactic administration of iodine 131 (131I), constitutes adequate therapy for most cases of papillary thyroid carcinoma. More extensive therapy should be considered for older patients and for those in whom the tumor exhibits extrathyroid extension or easily detectable multicentricity.

Anaplastic thyroid carcinoma. A study of 70 cases

Seventy cases of anaplastic thyroid carcinomas studied at the Universities of Florence (Italy) and Minnesota are presented. Three morphologic patterns were seen: spindle, giant cell, and squamoid, sometimes in combination. Ultrastructurally, evidence of epithelial differentiation was seen in most but not all cases studied. Immunohistochemically, a stain for cytokeratin using a monoclonal antibody was found the most useful adjunct to diagnosis. Unexpected positivity for carcinoembryonic antigen (CEA) was found in several squamoid tumors. The alleged frequent positivity of this tumor type for thyroglobulin and calcitonin was not confirmed. A third of the tumors were associated with a better differentiated component, of which, presumably, they represented a dedifferentiation. The extremely aggressive behavior of anaplastic thyroid carcinomas was confirmed amply in this series: all of the patients in whom follow-up information was available died of their tumor. Small cell tumors should not be included into the anaplastic category, since they invariably belong to other groups, i.e., malignant lymphoma, medullary carcinoma, and poorly differentiated ("insular") carcinoma.

Poorly differentiated ("insular") thyroid carcinoma. A reinterpretation of Langhans' "wuchernde Struma"

Twenty-five cases of a distinctive type of thyroid carcinoma are presented. The key microscopic features are: formation of solid clusters ("insulae") of tumor cells containing a variable number of small follicles; small size and uniformity of the tumor cells; variable, but consistently present mitotic activity; capsular and blood vessel invasion; and frequent necrotic foci, sometimes leading to the formation of "peritheliomatous" structures. Metastases to regional lymph nodes, lung, and bones are common, and these often lead to the patients' death. We view this tumor as a poorly differentiated carcinoma, situated morphologically and biologically in an intermediate position between the well-differentiated (papillary and follicular) and the totally undifferentiated thyroid tumors. We believe that it is closely related, if not identical, to the tumor type described by Langhans in 1907 as "wuchernde Struma."

Papillary carcinoma of the thyroid. A discussion of its several morphologic expressions, with particular emphasis on the follicular variant

Papillary carcinoma of the thyroid has been classically defined on the basis of the presence and even the predominance of papillary formations within the tumor. Changes in this traditional concept have evolved along two separate but related lines. The first is the realization that well-differentiated tumors having a papillary component, however minimal, will exhibit the behavior of papillary carcinoma even in the presence of extensive areas with a sclerosing, solid, or follicular pattern of growth. The second is an increased reliance on cytologic criteria (particularly the ground-glass nucleus) rather than architectural features for the identification of papillary carcinoma. Through the use of these criteria in association with various clinical features, evidence is put forward in support of the concept of a follicular variant of papillary carcinoma, i.e., a tumor type in which papillae are nil or absent but which still belongs by cell type and clinicopathologic behavior to the group of papillary carcinomas.