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PubMed1981

Oophorectomy in women with carcinoma of the colon and rectum.

Carcinoma of the colon and rectum metastasizes readily to the ovaries, and oophorectomy during operation upon the colon and rectum remains an effective surgical technique for precluding subsequent oophorectomy and, thereby, diminishing the morbidity of carcinoma of the colon and rectum in women. This procedure does not significantly affect the survival rate. Carcinoma of the ovary has become the fourth most common lethal cancer in women. Usually, the tumor is diagnosed after the development of ascites, mass and weight loss. The five year survival rate remains about 30 per cent. The incidence of carcinoma of the ovary in women with carcinoma of the colon and rectum is roughly five times the incidence of carcinoma of the ovary, that would be expected by chance. We believe the aforementioned observations strongly expand and reinforce the original proponents of prophylactic oophorectomy performed upon women with carcinoma of the colon and rectum and that, therefore, oophorectomy should be an integral part of operation upon the colon and rectum in women.

Adenocarcinoma↗
PubMed1994

Metastases from carcinoma of the colon and rectum detected in small lymph nodes by the clearing method.

A study of regional lymph node metastases was performed using the clearing method in 322 patients with carcinoma of the colon and rectum (140 with carcinoma of the colon and 182 with carcinoma of the rectum) who had undergone surgical resection. The mean number of nodes examined per patient was 76.4 and the metastatic rate (patients with metastases divided by the total of patients) was 61.4 percent, with a metastatic incidence (nodes with metastases divided by the total of examined nodes) of 6.4 percent for carcinoma of the colon using the clearing method. For carcinoma of the rectum, the mean number of nodes examined was 73.7 with a metastatic rate of 57.1 percent and a metastatic incidence of 7.1 percent. In contrast, node analysis by the conventional manual method resulted in a mean of 18.1 nodes being examined, with a metastatic rate and incidence of 42.1 and 12.8 percent, respectively, for carcinoma of the colon. Manual examination of lymph nodes in carcinoma of the rectum resulted in a mean of 21.2 nodes being examined, with a metastatic rate and incidence of 50.0 and 16.8 percent, respectively. Compared with the manual method, the clearing method provided a greater number of nodes, a higher metastatic rate and a lower metastatic incidence. These differences may be explained by the detection of metastatic regional nodes smaller than 4 millimeters in maximum diameter by the clearing method. By TNM classification there were more pN3 than pN2 lesions. The five year survival rate after curative resection was 78.5 percent for pN1 lesions, 45.7 percent for pN2 lesions and 45.4 percent for pN3 lesions for carcinoma of the colon and 72.7 percent for pN1 lesions, 75.0 percent for pN2 and 53.9 percent for pN3 lesions for carcinoma of the rectum. There was no significant survival difference between the patients with pN1, pN2 and pN3 carcinomas. The presence of regional nodes metastases should be examined in detail. Therapies and prognosis of carcinoma of the colon and rectum should be discussed based on accurate staging.

Colonic Neoplasms↗
PubMedDate not supplied

Endometriosis of the rectum causing bowel obstruction: a case report.

A 42-year-old pre-menopausal woman complaining of lower abdominal pain was referred to our hospital. A barium enema showed rectal stenosis and colonoscopy revealed that the mucosa at the stenotic site was normal with no cancerous changes. Pelvic computed tomography demonstrated an adhesion between the rectum and uterus and a thickened rectal wall. The patient underwent exploratory laparotomy under a diagnosis of rectal stenosis. The rectum was found to be surrounded by inflammatory fibrous tissue, which caused the stenosis. As no dissection plane was discernible between the rectum and uterus, low anterior resection of the rectum and hysterectomy were performed. Histological examination showed that endometrial-type glands extended circumferentially around the rectum and invaded the rectal submucosal layer and subsequently, endometriosis of the rectum was diagnosed.

Adult↗
PubMed2005

Contribution of the pudendal nerve to sensation of the distal rectum.

BACKGROUND: Anal and rectal sensory mechanisms and pudendal nerve function are important in the control of faecal continence. The contribution of the pudendal nerve to sensation of the distal rectum was investigated. METHODS: Heat thresholds in the anal canal, distal and mid rectum were measured using a specially designed thermoprobe. Rectal sensory threshold volumes were measured using the balloon distension method. Needle electrodes were inserted into the external anal sphincter. Pudendal nerve block was performed through a perineal approach, and completeness assessed by loss of electromyographic activity. Heat and rectal volume thresholds were measured again following unilateral and bilateral pudendal nerve block. RESULTS: The technique was successful in four of six volunteers. Bilateral pudendal nerve block produced complete anaesthesia to heat in the anal canal (P = 0.029), but had no effect on heat thresholds in the distal or mid rectum. Rectal sensory threshold volumes were also unaffected by pudendal nerve anaesthesia. CONCLUSION: Anal canal sensation is subserved by the pudendal nerve, but this nerve is not essential to nociceptive sensory mechanisms in the distal or mid rectum. The transition between visceral control mechanisms in the lower rectum and somatic mechanisms in the anal canal may have functional importance in the initiation of defaecation and the maintenance of continence.

Adult↗
PubMed1996

Laparoscopically assisted resection of the lower rectum.

We report a new laparoscopic approach to the resection of the lower rectum which has been successfully used in the treatment of a patient with a small rectal carcinoid tumor. Under general anesthesia a pneumo-peritoneum was established with CO2 gas insufflation and the rectum was mobilized from the sacrum including division of the lateral ligaments under the direct view of the laparoscope. The bowel was divided between the sigmoid colon and the rectum using an endoscopic linear stapler, and the rectum was everted through the anal canal. The lower rectum was transected extracorporeally using a linear stapler and the rectal stump was then returned to the anatomical position. An anvil of a circular stapling device into the oral colon stump through a small skin incision on the left lower abdomen was introduced and the shaft of the device through the rectal stump via anus was inserted. The device was then re-approximated under laparoscopic view and fired. Our procedure described here is applicable to the lower rectal lesion as a minimally invasive, safe, and useful therapeutic tool.

Carcinoid Tumor↗
PubMed1993

The intramural pelvic nerves immunoreactive for calcitonin gene-related peptide in the rectum of normal and aganglionosis rat.

The distribution of calcitonin gene-related peptide-like immunoreactive (CGRP-LI) nerves was investigated immunohistochemically in the rectum of normal, capsaicin-treated and congenital aganglionosis rats. The rectum of the normal rat was densely supplied with both extrinsic and intrinsic nerves exhibiting CGRP-like immunoreactivity. Numerous CGRP-LI nerve fibres were seen in both the myenteric and submucous plexuses. Intrinsic CGRP-LI nerve cell bodies were sparsely found in both the ganglionated plexuses, while a large inflow of extrinsic CGRP-LI nerves was characteristically observed in the rat rectum. CGRP-like immunoreactive fibres were abundant in the intramural pelvic nerves which ascend proximally in the intermuscular zone and connect with the myenteric plexus of the rat distal bowel. As compared with CGRP-positive fibres, SP- or SK-positive fibres in the intramural pelvic nerves were far less frequent. The treatment with capsaicin in the neonatal period led to a marked depletion of CGRP-immunoreactivity in these extrinsic nerves as well as in the most terminal varicose fibres seen in the whole layers of the rectal wall. These findings suggest that the vast majority of CGRP-LI fibres in the intramural pelvic nerves are sensory in nature, and that the positive nerve fibres of extrinsic origin directly innervate each layer of the rat rectum. These CGRP-LI sensory fibres associated with the intramural pelvic nerves, may be of importance in the regulation of rectal and colonic function in normal rats. A dense innervation of CGRP-LI nerve fibres, some of which showed the varicose appearance, was also found in the rectum of congenital aganglionosis rats.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1994

Co-localization of nitric oxide synthase and vasoactive intestinal peptide immunoreactivity in neurons of the major pelvic ganglion projecting to the rat rectum and penis.

Nitric oxide synthase (NOS)- and vasoactive intestinal peptide (VIP)-immunoreactive neurons projecting to the upper rectum or penis were examined using retrograde tracing combined with immunohistochemistry in the major pelvic ganglion of male rats. Five days after injection of Fluoro-Gold (FG) into the upper rectum or penis, the major pelvic ganglion was treated with colchicine. FG injected into the upper rectum labelled many ganglion neurons in the major pelvic ganglion. Immunohistochemistry showed that 37% of FG-labelled neurons were immunoreactive for NOS and 33% for VIP. After injection of FG into the penis, 41% of FG-labelled neurons were immunoreactive for NOS and 25% for VIP. Serial cryostat sections stained for NOS and VIP, respectively, showed the co-localization of NOS and VIP in the ganglion cells projecting to the rectum and penis. In the major pelvic ganglion of the colchicine-treated animals, about 17% of the ganglion cells were immunoreactive for NOS and 32% were immunoreactive for VIP. These neurons were small in diameter (less than 30 microns). A histogram showing cell sizes in cross-sectional areas of NOS-immunoreactive neurons coincided with that of VIP-immunoreactive neurons. Most of the NOS- and VIP-immunoreactive neurons were less than 600 microns. These results indicate that small neurons containing both NOS and VIP in the major pelvic ganglion project to the rectum and penis. In the penile erectile tissues and enteric ganglia, NO and VIP may be released from the same axons and may act concomitantly on the target tissue.

Amino Acid Oxidoreductases↗
PubMed1987

Net ion fluxes and zero flux limiting concentrations in rat upper colon and rectum during anaesthesia-induced aldosterone liberation.

Thiobutabarbital anaesthetized and abdominally operated control rats develop high endogenous plasma levels of both aldosterone and corticosterone during the course of a 12 h experiment. This effect was used as a model for examining 'acute' steroid action (i) on net ion and water fluxes and (ii) on zero flux luminal limiting concentrations in rat upper colon (proximal 50% of large intestine) and rectum (distal 40%). Experiments of both kinds consisted of 8 independent 90 min measuring periods. (i) In rectum net fluxes of Na, K, osmolytes (sum of all solutes) and water started at low levels around zero, began to rise about 2 h after plasma levels of aldosterone had increased, and reached plateau values around the 6th hour of anaesthesia. In upper colon, fluxes of Na, K, Cl, and osmolytes were high from the beginning and did not vary significantly with time. (ii) At zero flux conditions limiting concentrations of Na in the hormonally unstimulated phase of the experiment were 20 +/- 3 mM in upper colon and 22 +/- 3 mM in rectum. After maximal endogenous aldosterone liberation zero flux concentrations were 5.2 mM in upper colon and 2.2 mM in rectum, corresponding to luminal fluid to plasma ratios (LF/P) of 0.040 and 0.016, respectively. Amiloride reduced the maximal Na gradient in rectum to a LF/P of 0.3 but was not effective in upper colon and did not prevent the stimulating effect of aldosterone in this segment. Under all experimental conditions zero flow concentrations of K were higher than consistent with a solely passive distribution, indicating simultaneous passive and active secretion in both segments. In contrast to the findings of others, the luminal fluid remained isoosmolar with plasma in all zero flux experiments.(ABSTRACT TRUNCATED AT 250 WORDS)

Aldosterone↗
PubMed1997

Pelvic anatomy and pathology is influenced by distention of the rectum: defecoperitoneography before and after rectal filling with contrast medium.

PURPOSE: The aim of the present study was to evaluate how distention of the rectum with contrast medium at defecoperitoneography affected pelvic anatomy, i.e., position, form, and size, of organs and pouch of Douglas. PATIENTS AND METHODS: Twenty-six female patients with a peritoneocele at defecoperitoneography were selected for the present study. Radiographs taken at the start, before, and after filling the rectum with contrast medium were compared. RESULTS: There was an obvious change in the position of the organs in the pelvis when the rectum was distended with contrast medium. The peritoneocele disappeared completely in 19 of the patients and was reduced in size in the remaining 7 patients, and the enterocele disappeared completely in 13 patients. The small bowel and vaginal portion of the uterus moved cranially. CONCLUSIONS: A distended rectum may conceal existing pathology, such as peritoneocele and enterocele, at defecoperitoneography. Defecoperitoneography should, therefore, include a radiograph before the rectum is filled. This radiograph shows the habitual anatomy of the patient in the sitting position and may demonstrate pathologic findings.

Adult↗
PubMed2000

Contribution to the surgical anatomy of the ligaments of the rectum.

PURPOSE: Many authors have discussed the presence and the importance of the lateral ligaments of the rectum. Our contribution aims at clarifying some aspects of surgical anatomy that help in the preservation of the urogenital functions and may influence the surgical practice. METHODS: From 1994 to 1998 we examined 27 fresh cadavers and five embalmed pelves. We performed all dissections with a technique similar to that used for the surgical mobilization of the rectum. RESULTS: The lateral ligaments of the rectum are trapezoid structures originating from mesorectum and are anchored to the endopelvic fascia; as lateral extensions of the mesorectum, they must be included in the surgical specimen. According to our results, three main structures can be recognized laterally to the rectum: 1) the lateral ligament, which does not contain important structures; 2) the inferior hypogastric plexus and the urogenital bundle; and 3) the lateral neurovascular pedicle of the rectum that comprises the nervi recti and the middle rectal artery, both running under the lateral ligament, although at different angles. CONCLUSION: At the point of insertion into the endopelvic fascia, the lateral ligaments run close to the urogenital bundle. Nevertheless, the dissection at its attachment is safe if the urogenital bundle is kept under visual control.

Cadaver↗
PubMed1996

Primary malignant melanoma of the rectum.

We present a case of primary malignant melanoma arising in the rectum of a 71-year-old woman who had presented with intermittent rectal bleeding following bowel movement 2 months previously. Digital and sigmoidoscopic examination of the rectum revealed a 3 x 2 x 1 cm exophytic tumor with a granular surface in the rectum 35 mm from the dentate line. No increased pigmentation was detected. Biopsy revealed degenerated mucosa accompanied by severe infiltration of inflammatory cells, but no malignant cells. The tumor and normal mucosa surrounding the tumor was excised 12 days after the biopsy. Light microscopy revealed the tumor to consist of malignant melanocytes and showed that the tumor was surrounded by normal mucosa. Immunohistochemical staining with antimelanoma antibody and HMB-45 substuntiated the diagnosis. Clinical and laboratory examination excluded the presence of melanoma at sites other than rectum. The patient refused an abdomino-perineal resection of the rectum and combination chemotherapy was performed. She died 18 months after the initial operation due to local recurrences and metastases to pelvic lymph nodes, liver, and lung.

Aged↗
PubMedDate not supplied

Is the rectum usually empty?--A quantitative study in subjects with and without diarrhea.

The authors have investigated the frequency with which the rectum contains feces by recording the presence or absence of fecal contamination of the membrane or of discoloration by feces of the contents of dialysis bags placed in the unprepared rectum for one hour. Feces were present in the rectum in 31 per cent of 32 studies in normal control subjects, in 49 per cent of 80 studies in obese subjects (P less than 0.05 from controls), in 36 per cent of 28 studies in patients with the irritable bowel syndrome, and in 31 per cent of 103 studies in patients with ulcerative proctocolitis, whether or not they had diarrhea. Fecal staining of the bag and its contents occurred much more frequently in 27 studies in subjects with various other diarrheal diseases (67 per cent, P less than 0.02 from controls), including eight with steatorrhea (87 per cent, P less than 0.02 from controls). The frequency with which feces were present was unaffected by age, sex, or time of day of the study. These results provide quantitative support for the assertion that in subjects without diarrhea the rectum is usually empty. In patients with diarrhea or steatorrhea and no distal large intestinal inflammation, however, the rectum usually does contain fecal material.

Adolescent↗
PubMed2005

Segmental heterogeneity of electrogenic secretions in human ascending colon and rectum.

AIMS: We have attempted to ascertain putative segmental differences in the secretory responses of the human ascending colon and rectum. METHODS: From the mucosal biopsy samples of two segments, the short-circuit current (I(sc)) and tissue resistance (R(te)) were compared under control conditions, as well as after the induction of secretion, using a modified Ussing chamber. We also performed semiquantitative reverse transcriptase-polymerase chain reaction (RT-PCR) to detect and quantify transport proteins. RESULTS: The spontaneous I(sc) in the ascending colon was found to be greater than that in the rectum (P<0.01), whereas isobutylmethylxanthine/forskolin and carbachol (CCh) induced a greater rise in I(sc) in the rectum than in the ascending colon (P<0.05). When coupled with indomethacin pretreatment, the increase in Delta I(sc) after the addition of CCh and forskolin was significant as compared to that observed without pretreatment (P<0.05). However, in the rectum, the secretory response to CCh and forskolin was abolished to a significant degree by indomethacin (P<0.05). Moreover, these indomethacin-induced changes were reversed by the addition of PGE2. Upon semiquantitative RT-PCR analysis, the amounts of cystic fibrosis transmembrane regulator, KCNQ1, and CLCA1 mRNAs were not found to be different between the two segments. CONCLUSION: There was a clear segmental heterogeneity with regard to electrogenic secretion in the human colon, and this difference can be explained by differences in the ascending colon and rectum.

1-Methyl-3-isobutylxanthine↗
PubMed1987

Incidence of fecal incontinence after coloproctostomy below five centimeters in the rectum.

Anastomosis of the descending colon to the rectum below 5 cm can result in fecal incontinence. We have reviewed 90 patients who underwent radical resection of the rectosigmoid colon with very low anastomosis that healed; 88 patients resumed defecation per anus. Indications for the resections were recurrent squamous cell carcinoma after total pelvic irradiation, adenocarcinoma of the endometrium with invasion of the mesentery of the rectosigmoid colon, endometriosis with low rectal involvement, and serous carcinoma of the ovary with invasion of the rectosigmoid mesentery and irradiation stenosis of the rectum. The rectum was transected at the level of the levator ani or below resulting in less than 5 cm of rectum above the anus. All patients had reanastomosis, coloproctostomy, with the end-to-end anastomosis stapler. All coloproctostomies were protected by proximal diverting colostomy if one of three conditions existed: (a) total pelvic irradiation; (b) significant diverticulitis or other inflammatory bowel disease; and (c) inadequate or unprepared bowel at the time of surgery. The proximal diverting colostomies were closed 8-16 weeks postoperatively after demonstrable healing of the anastomosis. Of the 90 patients, 88 eventually resumed defecation per anus after coloprotostomies and 5 (5%) required replacement of the colostomy for fecal incontinence. Eighty-three patients (92%) had successful reanastomosis, closure of the proximal colostomy, and defecation per rectum without fecal incontinence.

Aged↗
PubMed1992

Responses of the rectum and oesophagus of the snail Helix aspersa to purine nucleotides and nucleosides.

1. Purine compounds were examined for pharmacological activity in the rectum and oesophagus of the garden snail Helix aspersa. 2. In the rectum, adenosine, AMP, ADP and ATP (above 10 microM) and acetylcholine (above 1 nM) consistently caused concentration-dependent contractions. The slope of the dose-response curve for ADP in the rectum was significantly steeper than for the other purine compounds. The contractile responses to the nucleotides and acetylcholine, but not adenosine, were selectively potentiated by physostigmine (1 microM). Atropine (1 microM) and tubocurarine (30 microM) failed to block the responses to the purines or acetylcholine. 3. In the oesophagus, adenosine, AMP, ADP and ATP (above 10 microM) and acetylcholine (above 1 nM) caused concentration-dependent contractions that were antagonised by atropine (1 microM). Tubocurarine (30 microM) failed to block the responses to the purine compounds or acetylcholine. Physostigmine (1 microM) potentiated the responses to ADP and acetylcholine but not ATP, AMP or adenosine. 4. In both the rectum and the oesophagus, the synthetic analogues of purine compounds including 2-chloroadenosine, alpha,beta-methylene ATP and 2-methylthio ATP were inactive up to a concentration of 100 microM. 5. Electrical field stimulation of the rectum and oesophagus produced consistent contractions which were unaffected by atropine (1 microM), tubocurarine (30 microM) or physostigmine (1 microM). These responses were not modulated by any of the purine compounds or their stable analogues. 6. The responses obtained appear novel even within known invertebrate purinergic systems, suggesting a differentiation of purinoceptor subtypes in this species.(ABSTRACT TRUNCATED AT 250 WORDS)

Acetylcholine↗
PubMed2004

Lymph node metastasis in T1 adenocarcinoma of the colon and rectum.

The biology of colorectal cancer differs according to location within the large intestine. To evaluate the clinical significance of tumor location as a risk factor for lymph node metastasis (LNM), we performed a detailed pathological review of T1 adenocarcinomas of the colon and rectum. T1 adenocarcinomas of the colon and rectum treated by radical resection (n=428) were identified from prospective clinical databases at two institutions. Tumor location was assigned as right colon (cecum to transverse), left colon (splenic flexure to sigmoid), or rectum (0-18 cm from AV). Pathology slides were reviewed, extent of submucosal invasion (sm width, sm depth) was quantified using an optical micrometer, and morphologic features of the cancer and its infiltrating margin were recorded. The overall rate of LNM was 10%. On univariate analysis, LNM was significantly more common in the rectum (27/176, 15%) compared to the left colon (13/160, 8%, p=.04) or right colon (3/92, 3%, p=.003). However, on multivariate analysis, deep submucosal invasion and lymphovascular invasion were independent and significant risk factors, whereas tumor location was not. T1 colorectal cancers have a progressively higher risk of LNM as their location becomes more distal. However, the increasing rate of LNM observed in cancers of the left colon and rectum is explained by a higher prevalence of high-risk pathologic features. In early colorectal cancers, tumor morphology is the strongest clinical predictor of metastatic behavior.

Adenocarcinoma↗
PubMed2005

Comparison between CT-based volumetric calculations and ICRU reference-point estimates of radiation doses delivered to bladder and rectum during intracavitary radiotherapy for cervical cancer.

PURPOSE: To compare CT-based volumetric calculations and International Commission on Radiation Units and Measurements (ICRU) reference-point estimates of radiation doses to the bladder and rectum in patients with carcinoma of the uterine cervix treated with definitive low-dose-rate intracavitary radiotherapy (ICRT). METHODS AND MATERIALS: Between November 2001 and March 2003, 60 patients were prospectively enrolled in a pilot study of ICRT with CT-based dosimetry. Most patients underwent two ICRT insertions. After insertion of an afterloading ICRT applicator, intraoperative orthogonal films were obtained to ensure proper positioning of the system and to facilitate subsequent planning. Treatments were prescribed using standard two-dimensional dosimetry and planning. Patients also underwent helical CT of the pelvis for three-dimensional reconstruction of the radiation dose distributions. The systems were loaded with 137Cs sources using the Selectron remote afterloading system according to institutional practice for low-dose-rate brachytherapy. Three-dimensional dose distributions were generated using the Varian BrachyVision treatment planning system. The rectum was contoured from the bottom of the ischial tuberosities to the sigmoid flexure. The entire bladder was contoured. The minimal doses delivered to the 2 cm3 of bladder and rectum receiving the highest dose (DBV2 and DRV2, respectively) were determined from dose-volume histograms, and these estimates were compared with two-dimensionally derived estimates of the doses to the corresponding ICRU reference points. RESULTS: A total of 118 unique intracavitary insertions were performed, and 93 were evaluated and the subject of this analysis. For the rectum, the estimated doses to the ICRU reference point did not differ significantly from the DRV2 (p = 0.561); the mean (+/- standard deviation) difference was 21 cGy (+/- 344 cGy). The median volume of the rectum that received at least the ICRU reference-point dose was 2.1 cm3. In 66 (71%) of 93 cases, <5 cm3 was treated to this dose. However, for the bladder, the estimated doses to the ICRU reference point were significantly lower than the D(BV2) (p <0.001); the mean difference was 680 cGy (+/- 543 cGy). The median volume of the bladder that received at least the ICRU reference-point dose was 13.0 cm3. CONCLUSIONS: Our data suggest that the estimated dose to the ICRU rectal point may be a reasonable surrogate for the DRV2. However, this result may not be applicable to other treatment guidelines and ICRT applicator systems. In contrast, the dose to the ICRU bladder point does not appear to be a reasonable surrogate for the DBV2. Correlation with late complications are needed to define the role of three-dimensional dosimetry in treatment planning.

Brachytherapy↗
PubMed2005

Localized lymphoid hyperplasia of the rectum resembling polypoid mucosa-associated lymphoid tissue lymphoma: a report of three cases.

Histologically, benign lymphoid hyperplasia of the rectum is usually characterized by large lymphoid follicles with active germinal centers and by a narrow surrounding mantle zone and marginal zone (MZ). We report here three cases of benign lymphoid hyperplasia of the rectum associated with prominent marginal zone hyperplasia, which caused serious difficulty in the differential diagnosis from the polypoid type of mucosa-associated lymphoid tissue (MALT) lymphoma. Colonoscopy demonstrated small sessile polyps in all three cases. Histologically, the lesions were characterized by a hyperplastic germinal center and expanded MZs. The expanded MZs contained numerous monocytoid B-cells (MBC) and scattered large transformed B-cells. Initially, combined colonoscopic and histological findings strongly supported a diagnosis of polypoid MALT-type lymphoma of the rectum. However, there were neither colonized lymphoid follicles nor lymphoepithelial lesions in any of the three lesions. MBCs and large transformed B-lymphocytes were CD43- and bcl-2-. Moreover, immunohistochemical and genotypic studies proved the polytypic nature of the B-lymphocytes in all three lesions. The present cases indicated that benign lymphoid hyperplasia of the rectum should be included in the differential diagnosis for polypoid MALT-type lymphoma of the rectum.

Aged↗