Melanosis coli in patients with colon cancer.

INTRODUCTION: Melanosis coli is a benign lesion affecting the mucosa of the large intestine. There is a relationship between the presence of melanosis and anthraquinone laxative use. Melanosis coli is also observed in patients with colon cancer, but there is doubt whether these two conditions are related. AIM: To analyze the correlation between melanosis and colon cancer. MATERIAL AND METHODS: We analyzed retrospectively 436 patients undergoing colon cancer surgery. There were 246 women and 190 men. Patients were divided into three age groups: under 50 years, between 51 and 65 years, and over 66 years. We analyzed sections of the cancer and intestinal mucosa from the tumor's proximal (2-5 cm) and distal (8-10 cm) zone. RESULTS: Melanosis coli was present in 52 patients, which represents 11.9% of patients with colon cancer. More often it was present in women. The most common location of melanosis and colon cancer was the terminal part of the large intestine. In patients below 50 years of age in both sexes melanosis coli did not occur. In men, melanosis was more common in the age group over 66 years. Intensity of pigmentation was higher in the tumor's distal zone. CONCLUSIONS: The incidence of melanosis coli increases with age, similar to that of colon cancer. Melanosis was not present inside tumors, in almost half of the cases it was not present in the proximal zone, and the degree of pigmentation increased in distal zone. The cause-effect relationship between melanosis coli and colon cancer remains uncertain.

[Adenomatoid tumors of the testis and epididymis]. / Guzy adenomatoidalne jadra i najadrza.

The authors report 8 adenomatoid tumors treated in the Urology Department of the Medical Academy of Warsaw by organ sparing surgery during 1985-2003. Microscopic and immuno-histochemic investigations confirmed their benign character and histiogenesis. Follow-up of 6 treated patients, over 5-15 years did not reveal recurrence of the neoplasm. Two patients were treated this year and are under medical observation.

Venous outflow system in rabbit gastric mucosa.

The purpose of this work was to compare the organisation of the gastric mucosal venous system in larger animals, exemplified by rabbits, with that of the rat and the hamster which we have described previously. Rabbits were given atropine and hexamethonium followed by intravital ligation of all veins draining the stomach, causing strong hyperaemia. The distribution of vessels was studied in the non-mounted mucosa, in mounts of mucosa cleared in light mineral oil and in paraffin or semi-thin plastic sections. We found that blood from rabbit gastric mucosa is drained by collecting venules, running from the subepithelial layer towards the muscularis mucosae. The collecting venules join the paramuscular vessels parallel and adjacent to the muscularis mucosae. Neighbouring venules form numerous arcade-like connections and gradually enlarge. Two venules and an arteriole form triplets initially situated at the luminal face of the muscularis mucosae and gradually passing onto its abluminal surface. In rats vascular triplets were absent and the collecting venules drained into paramuscular vessels joining submucosal veins. In hamsters both connections between paramuscular vessels and submucosal veins and the passing of vascular triplets across muscularis mucosae were observed. Contraction/relaxation of the muscularis mucosae may regulate the amount of blood in the venous system of the mucosa and change the intramucosal pressure, affecting movement of the tissue fluid and, indirectly, the function of the gastric cells.

Vessels involved in the venous outflow from glandular mucosa of hamster stomach.

Blood from the glandular part of hamster gastric mucosa is drained by collecting venules, running from the subepithelial layer towards lamina muscularis mucosae. To visualise vessels involved in the venous outflow, hamsters were exposed to atropine and subjected to intravital ligation of portal vein, causing strong hyperaemia. Distribution of vessels and their connections were studied a) in translucent, flat preparations of the glandular stomach, b) in thick sections of glandular mucosa cleared in the mineral oil, and c) in semi-thin plastic or paraffin sections. Collecting venules were drained by single vessels running parallel to the lamina muscularis mucosae (paramuscular venules), which, in turn, joined submucosal veins through openings in muscularis mucosae. Moreover, some collecting and paramuscular venules discharged into venules belonging to vascular triples composed of two venules and arteriole. The triplets were also parallel to muscularis mucosae. Triplets did not form connections with submucosal veins but passed on the abluminal surface of muscularis mucosae. Thus, some structural elements involved in venous outflow from glandular gastric mucosa differ from those in rats, in which vascular triplets were absent and all collecting venules drained into single paramuscular vessels. Contraction/relaxation of muscularis mucosae may regulate the amount of blood present in the venous system of the mucosa and the diameter of venules. Rhythmical changes of the latter could cause changes in intramucosal pressure, affecting movement of tissue fluid in the mucosa and thus the function of gastric cells.

Collecting and paramuscular venules in glandular mucosa of rat stomach.

Blood from the rat gastric mucosa is drained by collecting venules running from the subepithelial layer towards the lamina muscularis mucosae. Details of their structure were studied in translucent, flat strips of the glandular stomach, in thick sections of glandular mucosa cleared in mineral oil and in semi-thin plastic sections. The number and dimensions of collecting venule outlets revealed in flat strips of gastric mucosa increased after administration of atropine and papaverine and intravital ligation of the portal vein in comparison with that of intact animals or animals with intravitally ligated portal vein but without administration of relaxing agents. In hyperemic mucosa short venules running parallel to the lamina muscularis mucosae (paramuscular venules) and draining collecting venules were distinctly visible. Saccular outlets equipped with triangular protrusions usually intervened between these vessels, probably directing blood flow. Collecting venules were straight, curved, extended or two-armed. Furthermore, numerous collecting venules contained circumscribed dilatations (sacculi) connected with the lumen of the collecting venule. Connection of paramuscular and submucosal veins occurred within the muscularis mucosae. Thus, contraction of the muscularis mucosae might control the outflow of venous blood from the gastric mucosa. Conceivably, alternate contraction and relaxation of muscularis mucosae could cause expansion and collapse of collecting venules which, in turn, would facilitate the movement of glandular content to the surface of the stomach and/or movement of interstitial fluid between cells.