Jan Willem Arends

A multivariate analysis of pathologic prognostic indicators in large bowel cancer

A multivariate analysis of the pathologic data of 350 patients with primary colorectal cancer was performed. In addition to conventional parameters such as shape and size of the primary tumor, central node involvement, angioinvasive growth, grade, and stage, new variables such as the immunoreactivity patterns of carcinoembryonic antigen (CEA), CA 19‐9, mucin, serotonin, secretory component (SC), and the DNA index were tested for their potential prognostic value. Every variable except CA 19‐9, serotonin, and DNA showed significant prognostic information in univariate analysis. However, in the multivariate analysis stage was the predictive factor with the highest hazard ratio, but absence of central node involvement, tumors with diameters between 3.5 cm and 6 cm, exophytic tumor growth, well‐differentiated tumors, tumors with CEA immunoreactivity, absence for staining with serotonin, and diploid tumors also were included in the relative risk model. Thus, the afore mentioned variables appear to play a role in the establishment of a prognostic index.

Regression analysis of prognostic factors in colorectal cancer after curative resections

The clinical, laboratory, and pathologic data of 310 patients who had curative resections were prospectively collected and analyzed in a multiple step wise regression model. Although several factors (i.e., venous invasion) were of importance in univariate analysis, the following conclusions reflect the outcome and relative importance of the regression analysis only. Blood loss as an initial symptom and duration of symptoms were associated with a better prognosis. Location of the primary tumor, age, and sex did not appear to have prognostic value. Observations during operation such as palpable lymph nodes, fixity to adjacent organs, and tumor spill were related to a diminished tumor-free survival. Laboratory data (hemoglobin, leukocytes, ESR, GGTP, SGOT, SGPT, LDH, total protein, CEA) were tested for their potential prognostic values. Only a preoperative low protein level or an elevated CEA level were associated with an increased risk of death due to recurrent tumor. The histopathologic features (stage and grade), with the exception of venous invasion, were of relative importance in the determination of prognosis. The aforementioned variables can be included in a prognostic index on the base of which high-risk groups suitable for adjuvant studies can be identified.

Molecular interactions in the Vogelstein model of colorectal carcinoma

For about a decade, the model proposed by Fearon and Vogelstein has been the paradigm of the genetic alterations involved in the development of colorectal carcinoma. During this time, much information has become available on the function of the key genes in this model, as well as on their interactions. This review examines the impact of this new knowledge on the Vogelstein model. It is concluded that the model as such still stands and with a few modifications could even be strengthened in that, contrary to the original proposal, the order of genetic events seems to be essential. Crucial molecular events include derangement of the Wnt‐ and defects in the transforming growth factor β (TGFβ)‐signalling pathways, which exert a synergistic effect on the cell cycle. Finally, with loss of p53 function, several checks and balances are disrupted, which paves the way to gross chromosomal aberrations and aneuploidy. Copyright

A detailed analysis of K-ras point mutations in relation to tumor progression and survival in colorectal cancer patients

Point mutations in codon 12, 13, and 61 of the K‐ras gene are an early event in tumorigenesis of colorectal cancer, but the impact of number, type, and position of such mutations on the progression of adenomas as well as the clinical behaviour of colorectal carcinomas is not clearly established. A series of 35 adenomas and 117 carcinomas at various stages was subjected to single‐strand conformation polymorphism (SSCP) to analyse type, position and number of exon‐I K‐ras point mutations and to relate the results with patients survival. From our data we conclude that the number of K‐ras point mutated tumors shows a trend to increase with tumor progression. The number of multiple K‐ras point mutations, however, significantly increases with stage. Most mutations occur in the 1st or 2nd base of codon 12, whereas point mutations in the 3rd base are rare. In adenomas mutations, particularly G‐T transversions, in the K‐ras gene could indicate a propensity to malignant transformation. G‐A transitions and G‐C transversions of the second base are associated with metastasized tumors. Regarding survival, patients with K‐ras point mutated tumors did worse than their non‐mutated counterparts. G‐A transitions in the 1st and 2nd base and G‐C transversions in the 2nd base were associated with a poor prognosis as compared with G‐T transversions in both the 1st and 2nd base. Patient survival therefore is related to the occurrence and type, but not the location, of K‐ras point mutations.

Type IV collagen immunoreactivity in colorectal cancer: Prognostic value of basement membrane deposition

Using antibodies to type IV collagen, basement membrane (BM) deposition at the tumor‐stromal border was studied in 163 cases of colorectal carcinomas. Immunoreactivity was scored semiquantitatively as moderate/extensive versus limited BM deposition and correlated with Dukes stages and survival data. Cases with limited BM deposition showed an overall significant shorter survival and were overrepresented in Dukes Stages C/D. Stratification of the cases, for limited versus moderate/extensive BM deposition and Dukes Stages A/B and C/D, showed that in Dukes Stages C/D, cases with moderate/extensive BM deposition reached a plateau phase in the survival curve after 2 years. Cases with limited BM deposition showed a continuous downward course on the survival curve. The results suggest that imntu‐nostaining of BM in cases in Dukes C differentiates tumors with relatively high invasive and metastatic capacity from tumors with low invasive and metastatic capacity.

EB/RP gene family encodes tubulin binding proteins

Mutations in the adenomatous polyposis coli (APC) gene are linked to the dysplastic transformation of colorectal polyps and represent an early step in the development of colorectal tumors. Ninety‐four percent of all mutations result in the expression of a truncated APC protein lacking the C‐terminal region. The C‐terminal region of the APC protein may have a tumor suppressor function as its absence appears to be linked to the development of dysplastic lesions. Recently, we discovered and characterized a protein called RP1 which binds specifically to the C‐terminal region of the APC protein. We show now that RP1 and the other known members of the EB/RP family (EB1 and RP3) also bind directly to tubulin, both in vitro and in vivo. Immunohistochemical analyses reveal a distinct staining pattern during interphase as well as an association of RP1/EB1 with mitotic microtubule structures. The previously described puncta of the APC protein at the leading edge of membrane protrusions contact microtubule fibers that contain RP1 or EB1. Int. J. Cancer 81:275–284, 1999.

Adhesion of human endometrial fragments to peritoneum in vitro

OBJECTIVEnTo evaluate the adhesion of endometrial fragments obtained during the proliferative phase of the menstrual cycle to fresh human peritoneum obtained during abdominal surgery.nnnDESIGNnA prospective, descriptive, morphologic and cell biologic study.nnnSETTINGnTertiary care university medical center.nnnPATIENT(S)nSix female volunteers.nnnINTERVENTION(S)nAfter endometrial biopsies performed during diagnostic laparoscopy, endometrial fragments were generated by enzymatic digestion and mechanical separation. Peritoneum was obtained during abdominal operations for benign indications.nnnMAIN OUTCOME MEASURE(S)nAdhesion of endometrial fragments was studied by histologic examination and scanning and transmission electron microscopy.nnnRESULT(S)nAfter incubation, the mesothelium was intact in some areas, whereas in other areas mesothelial cells were damaged or absent. Adhesion of endometrial fragments was observed only at locations where the basement membrane was exposed. In areas largely denuded of mesothelial cells, endometrial fragments spread over the basement membrane to form monolayers.nnnCONCLUSION(S)nHuman peritoneum is suitable for studying the adhesion of endometrial fragments. Intact mesothelium prevents the adhesion of endometrial fragments, suggesting that trauma to the mesothelial lining is a prerequisite for endometrial cell adhesion.

Distribution pattern and marker profile show two subpopulations of reserve cells in the endocervical canal.

A previous immunophenotyping study in the fetal uterine cervix provided evidence for the existence of 2 subpopulations of reserve cells, one giving rise to glandular epithelium and the other to squamous epithelium (5). In this study, we investigated whether the adult uterine cervix also harbors different populations of reserve cells on the basis of their marker profile and distribution pattern. Sagittal sections from 10 normal uteri, comprising the region from ectocervix to lower uterine cavity, were histologically examined and immunostained for p63, bcl-2 and cytokeratins (CKs) 5, 7, 8, and 17. The endocervical canal consists of three regions, that is, a part lined with squamous epithelium, a part lined with endocervical cells and a part lined with tubal type epithelial cells. Histologically, we found reserve cells in all 10 investigated cervices, with an abundancy in the area beneath the endocervical columnar epithelium close to the squamo-columnar junction, and high in the endocervical canal where the invaginations consist of tubal type epithelium. In between, an area lined with endocervical columnar cells without reserve cells was identified. No reserve cells were detected in the endometrial epithelium. We defined the end of the endocervix as the point where the surface of the cervical canal and the invaginations are completely lined with tubal type epithelium. From this point, reserve cells were no longer found. Reserve cells show strong expression for p63, CKs 5 and 7, and moderate expression for bcl-2. CK17 is strongly expressed in the reserve cells at the squamo-columnar junction and to a lesser extent in the reserve cells close to the endometrium. Endocervical columnar cells usually express CKs 7 and 8 and sporadically also p63 and CK5. CK17 was only found in endocervical cells in the vicinity of CK17-positive subcolumnar reserve cells. Tubal-type epithelium was present in all samples and contained bcl-2, along with CKs 5, 7, and 8. As a result, bcl-2 and CK5 expression distinguishes tubal epithelium from endocervical columnar cells. We conclude that reserve cells are present in all investigated cervices along the entire cervical canal. The concentration of subglandular reserve cells is highest close to the squamo-columnar junction and in the upper third of the cervix. The marker profile of reserve cells is the same in all parts of the cervix, except for CK17, which shows a decreasing gradient from distal to proximal, indicating a subpopulation of distal reserve cells as progenitor for squamous and columnar epithelium, and proximal reserve cells that can serve as progenitor cells for columnar epithelium.

Evaluation of a menstrual cup to collect shed endometrium for in vitro studies

OBJECTIVEnTo evaluate whether a menstrual cup is a suitable instrument to collect antegradely shed endometrium for in vitro studies.nnnDESIGNnA prospective, descriptive, cell biological and immunohistochemical study.nnnSETTINGnTertiary care university medical center.nnnPATIENT(S)nNine female volunteers with regular cycles.nnnINTERVENTION(S)nMenstrual effluent was collected with a menstrual cup. Experience with the menstrual cup was described. Cytospin specimens, frozen sections, and cultures were prepared from the obtained menstrual tissue.nnnMAIN OUTCOME MEASURE(S)nThe acceptability of the menstrual cup. The presence and viability of endometrial tissue was evaluated using immunohistochemical staining and culture outcome.nnnRESULT(S)nAll women except one described the menstrual cup as acceptable. Menstrual effluent contained single cells, clumps of cells, and glandlike structures. After 5 days of culture, the endometrial tissue appeared to be viable. Immunohistochemistry showed positive staining for vimentin in most cytospin specimens, in all cryostat specimens, and in 10 of 17 cultures. Cytokeratin 18 stained most cytospin specimens, all cryostat specimens, and 10 of 17 cultures. Positive staining for BW495/36 was observed in most cytospin specimens, all cryostat specimens, and 11 of 17 cultures.nnnCONCLUSIONnA menstrual cup in an acceptable instrument to collect antegradely shed menstrual tissue. Menstruum contains viable endometrial tissue that can be used for in vitro studies of endometrium and endometriosis.

Classification of gastric carcinoma using the goseki system provides prognostic information additional to TNM staging

Due to the high variability of the epidemiology, genetics, morphology, and biologic behavior of gastric carcinoma, many classification systems are in use, e.g., the World Health Organization (WHO) classification; tumor differentiation; the criteria of Ming, Mulligan, and Laurén; and the recently introduced Goseki classification. In the authors opinion, the TNM staging is the most valuable classification system, with a prognostic value for survival.