Abstract
Clinical Features: Endometriosis usually becomes apparent in the reproductive years when the lesions are stimulated by ovarian hormones. Forty percent of the patient’s present symptoms in a cyclic manner, which are usually related with menses Pelvic pain, infertility and dyspareunia are the characteristic symptoms of the disease, but the clinical presentation is often non-specific [1].
Diagnosis and Investigations: A precise diagnosis about the presence, location and extent of rectosigmoid endometriosis is required during the preoperative workup because this information is necessary in the discussion with both the colorectal surgeon and the patient. Furthermore, almost all patients with intestinal endometriosis have lesions in multiple pelvic locations and it is difficult to know what symptoms are caused by the intestinal disease versus the pelvic disease.
Treatment: Treatment must be individualized, taking the clinical problem in its entirety into account, including the impact of the disease and the effect of its treatment on quality of life. Pain symptoms may persist despite seemingly adequate medical and/ or surgical treatment of the disease. In such circumstances, a multi-disciplinary approach involving a pain clinic and counselling should be considered early in the treatment plan.
Endometriosis is characterized by the presence of functional endometrial tissue consisting of glands and/ or stroma located outside the uterus [1], although implanted ectopically, this tissue presents histopathological and physiological responses that are similar to the responses of the endometrium [2].
Prevalence and Epidemiology
a) Reproductive lifestyle, especially a delay in childbearing
b) Poorly understood immunological factors
c) Some environmental factors, probably including exposure to a range of environmental toxins
d) Reproductive tract occlusion, such as an imperforate hymen.
Pathogenesis
Sampson’s Theory of Retrograde Menstruation
The implantation theory proposes that endometrial tissue passes through the fallopian tubes during menstruation, then attaches and proliferates at ectopic sites in the peritoneal cavity. Recent studies using laparoscopy have demonstrated that retrograde menstruation is a nearly universal phenomenon in women with patent fallopian tubes. Classic studies performed in the 1950s demonstrated viability of sloughed endometrial cells and the capacity to implant at ectopic sites. Patients with mullerian anomalies and obstructed menstrual flow through the vagina may have an increased risk of endometriosis. The anatomic distribution of endometriosis also provides evidence for Sampson’s theory [8].Coelomic Metaplasia Theory
The theory of coelomic metaplasia proposes that endometriosis may develop from metaplasia of cells lining the pelvic peritoneum. Iwanoff and Meyer are recognized as originators of this theory. A prerequisite of the coelomic metaplasia theory is that mesothelial cells lining the ovary and pelvic peritoneum contain cells capable of differentiating into endometrium. An attractive component of the coelomic metaplasia theory is that it can account for the occurrence of endometriosis anywhere mesothelium is found. This includes reports of endometriosis occurring in the pleural cavity. Pleural endometriosis could result from local metaplasia of pleural mesothelium. On the other hand, it could also result from transdiaphragmatic passage of peritoneal fragments of endometrium as well as vascular metastasis of endometrium. Coelomic metaplasia is thought to account for the rare occurrences of endometriosis reported in males. In these reports of endometriosis, the men were all undergoing estrogen therapy. Although coelomic metaplasia was a possibility, estrogen stimulation of mullerian rests could not be excluded. Likewise, the occurrence of endometrial carcinoma in males is thought to possibly arise from mullerian remnants. Still, further support for the coelomic metaplasia theory may be found in the study of benign and malignant epithelial ovarian tumors. Both are considered to be derivatives of germinal epithelium. The presence of ovarian surface endometriosis could be accounted for by this type of transformation [8].Induction Theory
The induction theory is an extension of the coelomic metaplasia theory. This theory proposes that menstrual endometrium produces substances that induce peritoneal tissues to form endometriotic lesions [8].Embryonic Rests Theory
Von Recklinghausen and Russell are credited with the theory that endometriosis results from embryonic cell rests. These embryonic rests, when stimulated, could differentiate into functioning endometrium. As described above, rare cases of endometriosis have been reported in men. Transformation of embryonic rests is a plausible explanation for this phenomenon [8].Lymphatic and Vascular Metastasis Theories
The lymphatic metastasis theory of endometriosis is often referred to as Hal ban’s theory. He reported that endometriosis could arise in the retroperitoneum and in sites not directly opposed to peritoneum. Sampson had also suggested that endometriosis could result from lymphatic and hematogenous dissemination of endometrial cells. An extensive communication of lymphatics has been demonstrated between the uterus, ovaries, tubes, pelvic and vaginal lymph nodes, kidney, and umbilicus. Metastasis of endometrial cells via the lymphatic system to these areas is therefore anatomically possible. These findings are consistent with a literature review showing a 6.7% incidence of lymph node endometriosis in 178 autopsy cases. Lymphatic and vascular metastasis of endometrium has been offered as an explanation for rare cases of endometriosis occurring in locations remote from the peritoneal cavity. In addition to pleural tissue, endometriosis has been reported in pulmonary parenchyma. Vascular or lymphatic metastasis may also explain cases of endometriosis that have been reported in bone, biceps muscle, peripheral nerves, and the brain [8].Composite Theory
Javert proposed a composite theory of the histogenesis of endometriosis which combines the implantation, vascular/ lymphatic metastasis, as well as a theory of direct extension of endometrial tissue through the myometrium. Along similar lines, Nisolle and Donnez have recently argued that the histogenesis of endometriosis depends on the location and ‘type’ of the endometriotic implant. For example, peritoneal endometriosis can be explained by the implantation theory. Ovarian endometriomas could be the result of coelomic metaplasia of invaginated ovarian epithelial inclusions. Rectovaginal endometriosis, which often resembles adenomyosis, could result from metaplasia of Mullerian remnants located in the rectovaginal septum. These composite theories are attractive in that they recognize a multifaceted mechanism of histogenesis. It seems logical that a disease with such variable manifestations may originate via several mechanisms [8].Altered Immunity
Alterations in immunologic response to retrograde menstruation have been implicated in the genesis and maintenance of the endometriotic lesion. This defective immunosurveillance may lead to decreased clearance of menstrual debris from the peritoneal cavity and may allow for attachment of ectopic endometrium to peritoneal surfaces. An abnormal immune response could also promote the persistence and growth of ectopic endometrial tissue [8].The “Neurologic Hypothesis”
It is a new concept in the pathogenesis of endometriosis: There is a close histological relationship between endometriotic lesions of the large bowel and the nerves of the large bowel wall. Endometriotic lesions seem to infiltrate the large bowel wall preferentially along the nerves, even at distance from the palpated lesion, while the mucosa is rarely and only focally involved [9].Pathology and Sites of Involvement
Sites
Endometriosis can be divided into intra- and extraperitoneal sites. In decreasing order of frequency, the intra-peritoneal locations are ovaries (30%), uterosacral and large ligaments (18%-24%), fallopian tubes (20%), pelvic peritoneum, pouch of Douglas, and gastrointestinal (GI) tract. Extra-peritoneal locations include cervical portio (0.5%), vagina and rectovaginal septum, round ligament and inguinal hernia sac (0.3%-0.6%), navel (1%), abdominal scars after gynaecological surgery (1.5%) and caesarian section (0.5%). Endometriosis rarely affects extraabdominal organs such as the lungs, urinary system, skin and the central nervous system [1]. Endometriosis affects the intestinal tract in 15% to 37% of patients with pelvic endometriosis [10], involvement have been reported from the small bowel to the anal canal, but more frequently the disease involves the rectum and the sigmoid colon (74%), followed by the rectovaginal septumn (12%), cecum (2%), and appendix (3%) . When the ileum is involved, the most common tract is the distal part. A full-thickness involvement of the colonic wall is infrequent since the mucosa is usually spared. One of the classic locations is the anterior rectal wall in the region of the pouch of Douglas. This can be single nodule or can simulate a cancer. Because of the invasive appearance, the disease can be mistaken for cancer [11].Gross and Microscopic Pathology of Bowel Endometriosis
The appearance and size of the implants are quite variable. Areas of endometriosis appear as raised flame-like patches, whitish opacifications, yellow-brown discoloration, translucent blebs, or reddish or reddish-blue irregularly shaped islands. The peritoneal surface may be scarred or puckered.The Microscopic Appearance
Of endometriotic tissue is similar to that of endometrium in the uterine cavity; the two major components of both are endometrial glands and stroma. Unlike endometrium, however, endometriotic implants often contain fibrous tissue, blood, and cysts (Figure 1(a) & 1(b)).
Figure 1(a): Low-power image of the colonic wall, with
a few endometrial glands and stroma embedded in the
muscular layer.
Figure 1(b): High-power view of the colonic wall, with
endometrial glands and stroma embedded in the smooth
muscle of the colon [12].
Link to Cancer
Figure 2(a): Rectal endometriod adenocarcinoma with
adjacent focus of endometriosis (hematoxylin-eosin, 20x).
a) the presence of both malignant and benign endometrial
tissue in the same organ.b) the demonstration of cancer arising in the tissue and not invading it from elsewhere.
c) the finding of tissue resembling endometrial stroma surrounding characteristic glands.
Years later, Scott suggested an additional qualification to complete Sampson’s criteria: the demonstration of microscopic benign endometriosis contiguous with the malignant tissue [10]. Endometriosis and its possible malignant changes should be taken into account in the differential diagnosis of intestinal masses in females. Also, clinical suspicion for malignancy should be aroused in patients with abdominal pain or rectal bleeding and a previous history of quiescent endometriosis. Recognition of these lesions is important because of the different management required by primary gastrointestinal neoplasms and by those arising from endometriosis. These differences may have significant clinical implications [10].
Clinical Features
Differential diagnosis [1]
a) irritable bowel syndrome,b) infectious diseases,
c) ischemic enteritis/colitis,
d) inflammatory bowel disease
e) neoplasm
f) Other causes of intestinal obstruction (Acute/chronic, small/large bowel)
Diagnosis and Investigations
Colonoscopy
Although endoscopic diagnosis of colonic endometriosis has been reported, the mucosa is usually normal or shows minimal mucosal abnormalities, friability, extrinsic process or fibroses stenoses [1]. Endoscopic biopsies usually yield insufficient tissue for a definitive pathologic diagnosis as endometriosis involves the deep layers of the bowel wall [14]. Endometriosis can induce mucosal changes without any specific pattern, which mimic findings of other diseases such as inflammatory bowel disease, ischemic colitis or neoplasm [1]. Colonoscopy is helpful to rule out colorectal malignancy [11].Double Contrast Barium Enema
Radiologically, lesions of endometriosis are either of constricting and polypoid type or both. On barium studies, radiographic findings caused by implants in the ileum are similar to those in the colon. Rectosigmoid or cecal endometriosis on double contrast barium enema studies is seen as an extrinsic mass with speculation and tethering of folds [1]. Shortening or flattening of the bowel wall, crenulation of the mucosa, or a combination of these factors [15], Double-contrast barium enema may be effective in determining the precise location of the endometriotic nodules, but it cannot clearly demonstrate the depth of parietal involvement. Furthermore, the experience of the radiologist in the diagnosis of bowel endometriosis remains a critical limit of this technique [13] (Figures 3 & 4(a & b)).
Figure 3: Thirty-four years old woman with suspected intestinal implants of endometriosis. A and B, Lateral A and oblique B
spot images show three endometriotic lesions exhibiting extrinsic mass effect with crenulation of contour and speculation that
are direct signs of infiltration of bowel wall (arrows). Small polypoid lesion (arrowhead) is benign tubular adenoma confirmed
at surgery [15].
Figure 4(a): Twenty-eight years old woman with suspected intestinal implants of endometriosis and finding of rectal
localization of intestinal endometriosis. DCBE image shows extrinsic mass effect and speculation (arrow) of rectal wall that
appears infiltrated [15].
Figure 4(b): Twenty-three years old woman with suspected intestinal implants of endometriosis. DCBE examination showing
pathologic pelvic process involving bowel serosa at rectosigmoid junction. Finding of extrinsic mass effect and speculation
(arrows) owing to poor wall distention after air insufflation suggesting wall infiltration [15].
Transvaginal Us
Transvaginal ultrasonography can be useful not only in the first-line exploration of the pelvic cavity, but also in diagnosing rectosigmoid endometriosis. However, relevant limitations of transvaginal ultrasonography consist in the impossibility of determining the exact distance of rectal lesions from the anal margin and of evaluating precisely the depth of rectal wall involvement. In addition, locations above the rectosigmoid junction might be beyond the field of view of a transvaginal approach and limited by the presence of air for a transabdominal approach [15]. Transvaginal us combines with rectal water contrast is more accurate than TVS in diagnosing rectal infiltration reaching at least the muscularis propria in women with rectovaginal endometriosis. However, this exam cannot determine whether the infiltration reaches the rectal submucosa. RWC-TVS may be more painful than TVS, therefore it could be used when TVS cannot exclude the presence of rectal infiltration in women with rectovaginal endometriosis [15] (Figure 5).
Figure 5: A large rectovaginal nodule infiltrating the bowel muscularis (indicated by the asterisk) demonstrated by Rectal
Water Contrast- Transvaginal Sonography (RWC-TVS) [16].
CT & MSCT
CT is not the primary imaging modality for evaluation of bowel endometriosis, although it can occasionally demonstrate a stenosing rectosigmoid mass. Multislice CT (MSCT) has a great potential for detecting alterations in the intestinal wall, especially if it is combined with enteroclysis (MSCTe). Biscaldi et al carried out a study on 98 women with symptoms suggestive of colorectal endometriosis and MSCTe identified 94.8% of bowel endometriotic nodules [1]. Biscaldi et al reported the usefulness of multislice CT combined with distention of the colon by rectal enteroclysis for bowel endometriosis. The sensitivity was 98.7% and specificity was 100% in identifying women with intestinal endometriosis. This method is thought to be very helpful for diagnosing intestinal endometriosis, but requires bowel preparation, such as the need for a low-residue diet for 3 d, drinking of 4-6 doses of a granular powder dissolved in 500 mL of water per dose and intravenous administration of iodinated contrast medium. This technique is thus inappropriate for patients with obstructive symptoms or allergy to iodinated contrast medium [3] (Figures 6 & 7).
Figure 6: Endometriotic nodule infiltration the muscular layer, A: Axial MSCTe image of the abdomen, the arrow indicates
the endometriotic nodule. The lesion is enhanced, and it infiltrates the bowel wall involving the muscular layer. B: Coronal
reconstruction demonstrating the extension of the sigmoid endometriotic nodule (indicated by the arrow) C: Formaldehydefixed
resected bowel segment, the endometriotic nodule of the sigmoid colon was previously demonstrated by MSCT [14].
Figure 7: Endometriotic nodule infiltration the muscular layer, A: Axial MSCTe image of the abdomen, the arrow indicates
the endometriotic nodule. The lesion is enhanced, and it infiltrates the bowel wall involving the muscular layer. B: Coronal
reconstruction demonstrating the extension of the sigmoid endometriotic nodule (indicated by the arrow) C: Formaldehydefixed
resected bowel segment, the endometriotic nodule of the sigmoid colon was previously demonstrated by MSCT [14].
Magnetic Resonance Imaging (MRI)
Magnetic resonance imaging (MRI) has a high sensitivity (77%- 93%) in the diagnosis of bowel endometriosis. The depth of rectal wall infiltration by endometriosis is poorly defined by MRI. A combination of MRI and rectal endoscopic ultrasonography (EUS) has recently been proposed. When retroperitoneal infiltration is present, it is mandatory to know if the bowel wall is involved in order to identify patients requiring bowel resection. Both rectal EUS sensitivity and negative predictive value range from 92% to 100%. The specificity and positive predictive value are rather poor, which are 66% and 64%, 83% and 94%, respectively, as reported in two different studies [1]. Imaging examination is thus essential for the preoperative diagnosis of intestinal endometriosis, but some reports have described preoperative confusion between this disease and cancer according to colonoscopy and CT with barium enema, particularly in patients with lesions involving the mucosal surface. In such patients, MRI is helpful for differential diagnosis. In a typical endometrial lesion, MRI showed signal hyperintensity on T1-weighted imaging and signal hypointensity on T2-weighted imaging. However, smooth muscle components are reportedly recognized frequently in endometrial lesions. In such lesions, as seen in the present case, MRI indicates signal hypointensity on both T1- and T2-weighted imaging, and differential diagnosis from other diseases such as cancer and gastrointestinal stromal tumor is thus difficult. In fact, Chapron et al reported that MRI specificity for deeply infiltrating endometriosis was 97.9%, but sensitivity was only 76.5% [3] (Figures 8 & 9).
Figure 8: T2- weighted axial view: fecal matter attached to the rectal wall, simulating thickening of the rectal wall [17].
Figure 9: T2- weighted sagittal (a) and axial (b) views.
Nodule of the rectosigmoid junction adhering to the posterior surface of the uterus [17].
Nodule of the rectosigmoid junction adhering to the posterior surface of the uterus [17].
Transrectal EUS
The involvement of the colon is difficult to detect because the implants rarely invade through the intestinal mucosa. For this reason, the rectal ultrasound is of primary importance to assess the rectal involvement [11]. Also, the depth of rectal wall infiltration by endometriosis is poorly defined by MRI. A combination of MRI and rectal endoscopic ultrasonography (EUS) has recently been proposed. When retroperitoneal infiltration is present, it is mandatory to know if the bowel wall is involved in order to identify patients requiring bowel resection [1]. Endoscopic ultrasonography is also a useful and noninvasive examination for the diagnosis of intestinal endometriosis. Sensitivity and specificity are reportedly about 97% for the diagnosis of rectal involvement in patients with known pelvic endometriosis. In addition, EUS-FNAB provides accurate tissue and may be the only procedure for correct preoperative diagnosis of intestinal endometriosis, but the overall specificity, sensitivity and accuracy of EUS-FNA for neoplasms of the gastrointestinal tract are reportedly 88%, 89% and 89%, respectively [3]. Among these examinations, it is considered that MRI and EUS (and/or EUS-FNAB) are the most useful examinations for intestinal endometriosis. However, it is important to perform valuable examinations for diagnosis of intestinal endometriosis, including radiological, histological and etiological examinations, as the condition basically involves a benign lesion requiring minimally invasive treatment [3] (Figure 10).
Figure 10: Rectal endoscopic ultrasonography showing a uterosacral endometriosis nodule (2 cm x 3 cm) with bowel infiltration.
P = probe, M = mucosa, SM = submucosa, MP = muscularis propria [18].
P = probe, M = mucosa, SM = submucosa, MP = muscularis propria [18].
7- Serum Markers
There is a great interest in the use of serum markers to diagnose endometriosis, but they are not sufficiently accurate for use in clinical practice. Cancer antigen CA-125 has been used to monitor the progress of endometriosis [16]. CA19-9 has a lower sensitivity than CA-125, and cytokine interleukin-6 may be more sensitive and specific than CA-125 [1]. Mol et al reported a systematic review of the diagnosis of endometriosis and concluded that serum CA125 level may be elevated in endometriosis, but this measurement had no value as a diagnostic tool compared to laparoscopy [3].Laparoscopy
Laparoscopy is a primary diagnostic and therapeutic tool providing the opportunity to explore the abdominal cavity and obtain biopsies. The magnified vision enables the surgeon to operate with the best possible exposure. Although it was once believed that intestinal endometriosis was best managed by hormonal regimens or surgical castration, the advent of laparoscopic surgery has dramatically changed this approach [11] (Table 2).Treatment
The Treatment of Uncomplicated Intestinal
Operative Technique
Postoperative Complications
a) Internal hemorrhage
b) Bowel fistula
c) Vaginal fistula
d) Retention of urine
e) Constipation
f) Abdominal wall hematoma
g) Ureteral injury and stenosis
h) Bladder perforation
i) Uterine perforation
j) Cystitis
k) Adynamic ileus
l) Mechanical bowel obstruction
m) Peritonitis
n) Peritoneal effusion
Outcome after Surgery
Read More Lupine Publishers Journal of Surgery Articles : https://surgery-casestudies-lupine-publishers.blogspot.com/
Read More Lupine Publishers blogger Articles: https://lupinepublishers.blogspot.com
No comments:
Post a Comment