Metastasis of rectal cancer to lymph nodes and tissues around the autonomic nerves spared for urinary and sexual function

Voiding dysfunction after pelvic colorectal surgery

Bladder dysfunction following colorectal surgery may be related to extirpative procedures in the region of the pelvic autonomic plexus. The most common etiology is from autonomic disruption during abdominoperineal or low anterior resections. Contemporary technical modifications have allowed surgeons to achieve oncologic control while preserving the autonomic nerves that innervate the bladder and sexual organs. Although these modifications have resulted in a significant decrease in the incidence of postoperative bladder dysfunction, bladder dysfunction continues to be a source of significant morbidity after surgery. In this patient population, symptoms are not reliable for accurate diagnosis. The use of urodynamics provides objective measurements of bladder and outlet function and are paramount in providing an accurate diagnosis and in recommending treatments. Follow-up and treatment are highly individualized based on urodynamic findings, patient expectations, patient abilities, and family support. This article provides an overview of pertinent neuroanatomy, diagnosis, urodynamic interpretation, and treatment related to bladder dysfunction following pelvic colorectal surgery.

The developmental anatomy of the human superior hypogastric plexus: A morphometrical investigation with clinical and surgical correlations

The superior hypogastric plexus (SHP) is the part of the autonomic nervous system, which is responsible for the sympathetic innervation of pelvic organs and extrapelvic genitals in humans of both sexes. The SHP also functions as the anatomic pathway for the major part of visceral sensitive fibers originating from pelvic viscera. In this study, the morphology of the SHP was analyzed through anatomical dissections performed both in human adult and fetal cadavers. A computerized morphometrical investigation of the SHP was also performed and the resulting quantitative data statistically assessed. The comparison between fetal and adult SHP revealed that in the male group there was a developmental increase of six times (in height) and of about five times (in width); while in the female group, there was a developmental increase of 3.5 times both in height and width values. In addition, the distance from the superior border of the SHP to the bifurcation of the common iliac arteries presented a developmental increase of about six times in the male group, and about four times in the female group. We propose an original morphological classification with six types, based upon the anatomical arrangement of the nervous fibers in this autonomic plexus.

Rationale of pelvic autonomic nerve preservation in rectal cancer surgery based on immunohistochemical study

PURPOSE

Previous studies revealed that the incidence of cancer cell involvement along the pelvic autonomic nerves ranged from 4 to 14%. However, patients' profiles and methodologies differed among the studies. This study was conducted to clarify the incidence of cancer cell involvement in and around the pelvic autonomic nerves immunohistochemically.

METHODS

Immunohistochemical staining was performed on pelvic autonomic nerve specimens resected from 17 patients with p-Stage I-III lower rectal cancers. Antibodies used were pan-cytokeratin (AE1/AE3) for staining cancer cells, S-100 for autonomic nerves, and D2-40 for lymphatic vessels. Lymphatic permeation around the pelvic autonomic nerves was defined as present when AE1/AE3-positive cells were detected in D2-40-stained lymphatic vessels. The presence of metastasis to the interstitial tissue or contaminants was also recorded.

RESULTS

TNM staging was stage I in 1, stage II in 5, and stage III in 11 cases, respectively. No cases had lymphatic permeation or metastasis to the interstitial tissue in and around the pelvic autonomic nerves. Cancer cell contaminants were seen in four cases (23%). In three cases (18%), metastatic nodes were located at the root of the middle rectal artery, very close to the pelvic autonomic nerves.

CONCLUSIONS

Cancer cell involvement was not seen in and around the pelvic autonomic nerves, suggesting that complete pelvic autonomic nerve preservation may be feasible, unless nerves are invaded by the tumor. In some cases, however, metastatic nodes were seen very close to the nerves. Meticulous lymph node dissection along the pelvic autonomic nerves is mandatory.

Infralevator lymphatic drainage of low-rectal cancers: preliminary results

BACKGROUND

Some low-rectal cancers may spread into or recur in the inguinal lymph nodes despite optimal resection of the primary tumor. Hence, we hypothesized that lymphatic drainage of low-rectal malignancies may be inhomogeneous and that an extramesorectal route may be involved in at least some cases. The idea of our preliminary study was to analyze the potential lymphatic drainages in low-rectal cancer patients.

METHODS

The first stage of the experiment included two consecutive low-rectal adenocarcinoma patients (free from inguinal lymph node metastases), in whom the lymphatics of the primary tumor were traced with Patentbalu dye. During the second stage the records of 206 consecutive low-rectal cancer patients were analyzed for presence of inguinal lymph node metastases.

RESULTS

An evaluation of specimens from two rectal cancer patients revealed extramesorectal lymphatic drainage of the primary tumor besides the mesorectal route. An analysis of 206 patients revealed six cases of inguinal node metastases. Median age of patients was 55 years. They were all diagnosed with rectal adenocarcinoma, T3 or T4 tumors with G2 or G3 grade.

CONCLUSION

The demonstration of an alternative route of lymphatic drainage suggests that more radical surgical procedures are necessary for successful treatment of low-rectal cancers.

The incidence of lateral pelvic side-wall nodal involvement in low rectal cancer may be similar in Japan and the West

BACKGROUND

There is an East-West divide with regard to the frequency, significance and management of lateral pelvic side-wall nodes associated with low rectal cancer. In Japan, removal of nodes is considered essential in curative treatment of selected patients. In the West, involved nodes are generally considered as metastatic disease. There may be international differences in rectal cancer behaviour.

METHODS

A review of relevant studies was undertaken using PubMed, Cochrane Library and personal archives of references; further cross-referencing was conducted. Historical developments, relevant anatomy and reports on lateral pelvic lymphadenectomy (LPLD) were identified. Outcomes following LPLD were assessed.

RESULTS

The low rectum has lateral lymphatic drainage. Enhanced pelvic imaging techniques suggest that some patients with low rectal cancer have lateral pelvic lymph node involvement. However, there is no universal agreement on the definition of either the rectum or low rectal cancer. Selective use of LPLD has led to good outcomes in Japan. An alternative strategy might be neoadjuvant therapy for involved lateral nodes.

CONCLUSION

Pelvic imaging and correlation with pathological findings are crucial in the assessment of lateral pelvic side-wall nodes. East and West should combine their experience of preoperative staging, surgical treatment and pathological assessment of low rectal cancer.

Oncologic results of laparoscopic D3 lymphadenectomy for male sigmoid and upper rectal cancer with clinically positive lymph nodes

BACKGROUND

Many Japanese surgeons routinely perform extended D3 lymph node dissection for the treatment of advanced rectosigmoid cancer with a view to achieving better tumor control. However, the application of a laparoscopic approach to perform D3 lymphadenectomy has been challenging. This phase 2 prospective study aimed to explore the oncologic results of this surgical approach.

METHODS

The study was conducted during a 6-year period, in consideration of median follow-up time being >3 years. The study subjects were tumor, node, metastasis system stage III rectosigmoid cancer staged by clinical images. The extent of D3 dissection and the postoperative lymph node mapping were according to the guidelines of the Japanese Society for Cancer of the Colon and Rectum. Patients were stratified according to the histopathologically proved highest level of involved lymph nodes and placed into N0, N1, N2, and N3 groups. The primary end points of the study were the estimated time to recurrence and 5-year recurrence rate of cancer after laparoscopic D3 dissection.

RESULTS

The estimated 5-year recurrence rate (20% in the N0 group [n = 10]; 25% in N1 [n = 44]; 33.3% in N2 [n = 30]; and 42.8% in N3 [n = 14]), time to recurrence (mean [95% confidence interval] 59.8 [42.6-76.9] months in the N0 group; 56.8 [48.3-65.2] months in N1; 46.8 [37.5-56.1] months in N2; and 43.9 [28.3-59.4] months in N3), and recurrence patterns were without significant difference (all P values >.05) among N0, N1, N2, and N3 groups. Therefore, by laparoscopic wide anatomic dissection, patients with lymph node involvement could be treated as well as those without lymph node metastasis. Laparoscopic D3 dissection facilitated the collection of more lymph nodes (mean +/- standard deviation, 27.4 +/- 4.2) for histopathologic examination. Mapping of dissected lymph nodes showed that 18.2% (16 of 88) patients had skip lymph node metastasis. D3 dissection facilitated upstaging of cancer (from N0 to N3) in five patients (5.1%). However, this procedure resulted in transient voiding dysfunction in 77.5% patients and loss of ejaculatory function in 91.7%. By laparoscopic approach, the D3 lymph node dissection was safely performed through small wounds, resulting in quick functional recovery and only moderate blood loss (324.8 +/- 44.5 mL), but at the expense of a long operation time (294.4 +/- 34.8 minutes).

CONCLUSIONS

The good short-term oncologic results and quick convalescence mean that the laparoscopic D3 dissection may be recommended for patients with stage III rectosigmoid cancer who could accept the genitourinary dysfunction.

Feasibility of autonomic nerve-preserving surgery for advanced rectal cancer based on analysis of micrometastases

Background

Autonomic nerve preservation has been advocated as a means of preserving urinary and sexual function after surgery for rectal cancer, but may compromise tumour clearance. The aim of this study was to determine the incidence of micrometastasis in the connective tissues surrounding the pelvic plexus.

Methods

The study included 20 consecutive patients who underwent rectal surgery with bilateral lymph node dissection for advanced cancer. A total of 78 connective tissues medial and lateral to the pelvic plexus and 387 lymph nodes were sampled during surgery. All connective tissue samples and 260 lymph nodes were examined for micrometastases by reverse transcriptase–polymerase chain reaction (RT–PCR) after operation. All patients were followed prospectively for a median of 36·0 months.

Results

Of 245 histologically negative lymph nodes, 38 (15·5 per cent) were shown by RT–PCR to harbour micrometastases. However, micrometastases to tissues surrounding the pelvic plexus were detected in only two (3 per cent) of 78 tissues, that is in two of 20 patients. Clinical follow-up showed that the two patients had a poor prognosis owing to distant metastases.

Conclusion

Autonomic nerve-preserving surgery may be feasible for advanced rectal cancer, but study of more patients positive for micrometastases is required.

The assessment of urinary function following extended lymph node dissection for colorectal cancer

AIMS

The aim of the current study is to demonstrate whether the effects of extended systematic lymph-node dissection (ESLND) on urinary dysfunctions differ from those of curative radical surgery (CRS) only for rectal cancer.

METHODS

We present data about our patients who underwent rectal resection for rectal cancer over 5 years. One hundred and seventy patients with rectal cancer were reviewed with respect to surgical procedures and post-operative urinary problems.

RESULTS

We performed CRS on 146 patients and CRS+ESLND on 24 patients, and analysed the incidence of post-operative urinary dysfunction in both groups. Urinary incontinence rates were 39 and 58%, urinary retention rates were 4 and 16%, for the patients from CRS group and CRS+ESLND group, respectively.

CONCLUSIONS

We conclude that the addition of ESLND to CRS does not increase the frequency of post-operative urinary dysfunction, apart from an increased risk of urinary retention.

Ganglions et cancer du rectum

Nodal invasion is a major prognostic factor of rectal cancer. Lymphatic extension of rectal cancer usually involves the mesorectal nodes then the inferior mesenteric chain but in 14% of patients, particularly with cancer of the lower rectum, metastasic nodes can be observed in the internal or lumboaortic chains situated beyond the usual territory of nodal dissection. On average, 30 nodes are examined on a proctectomy specimen, but with wide interindividual variation. The tumor can be adequately staged if at least 15 nodes are examined with little risk of not recognizing nodal metastasis. Metastatic nodes of rectal cancer are almost always small, more than 90% measuring less than 10 mm and 70% less than 5 mm. The number of invaded nodes and the total number of examined nodes are prognostic factors for survival. Hypofrationated preoperative radiotherapy does not alter the nodal status but a long radiotherapy protocol (45 Gy over 5 weeks) reduces significantly the total number of nodes examined without changing the number of metastasic nodes. Micrometastases (measuring less than 2 mm), identified by immunohistochemistry or gene amplification, can be detected in 25 to 70% of nodes considered metastasis-free at the usual microscopic examination. The prognostic value of these micrometastases remains to be established. The first node draining the tumor (sentinel node), which can be detected rapidly with dye infusion, appears to provide a good picture of the nodal status, the risk of finding an invaded node if the sentinel node is metastasis-free is less than 5%.

Regeneration of hypogastric nerve using a polyglycolic acid (PGA)-collagen nerve conduit filled with collagen sponge proved electrophysiologically in a canine model

The hypogastric nerve (HGN) is a sympathetic nerve in the peritoneal cavity and controls urinary and seminal functions. In this study, the regeneration of HGN was determined by using a new type of an artificial nerve conduit, polyglycolic acid (PGA)-collagen nerve conduit filled with collagen sponge in two dogs. A PGA-collagen nerve conduit (diameter=2 mm) was interposed in a 10 mm gap of the right HGN. The regeneration of the HGN was evaluated electrophysiologically 8 months after the operation. The intraluminal pressure of spermatic duct and the bladder neck were elevated 80 mmHg and 25 mmHg respectively by the stimulation across the regenerated HGN. The prostate contraction was also elicited. The responses diminished after the excision of the regenerated portion of HGN. These results proved the regeneration of HGN and this nerve conduit will be great help for patients who suffer from urinary and seminal disturbances.

Afferent and efferent lymph-collecting vessels of the submandibular nodes with special reference to the lymphatic route passing through the mylohyoid muscle

BACKGROUND

Although metastasis of cancer in the oral region to the submandibular node is well described, there has been no anatomic representation of lymph vessels penetrating the oral floor and draining into the node.

MATERIALS AND METHODS

Ninety specimens were obtained from formalin-fixed, donated cadavers. Histologic observations using serial sections followed the macroscopic observations.

RESULTS

In 19 of 90 specimens, we found afferent collecting lymph vessels exiting from the mylohyoid surface and draining into the preglandular submandibular node. In 3 of the 19 specimens, collecting vessels passing through the narrow muscle gap with or without arteries, veins, and nerves were identified histologically. The postglandular submandibular node was not evident in the drainage route.

CONCLUSIONS

Although it carries a low incidence, because of the direct lymphatic route or pathway between the oral region and preglandular submandibular node, the pathologically positive supraomohyoid node sometimes seems to be found even in elective neck dissection. However, we speculate that sentinel node investigation would reveal the much more critical role of the jugulodigastric node not only as the actual sentinel node but also as the common terminal node along the various drainage routes from the oral region.

Does perifascial rectal excision (i.e. TME) when combined with the autonomic nerve-sparing technique interfere with operative radicality?

OBJECTIVE: The lymphatic drainage from the rectum was studied to evaluate if the autonomic nerve sparing dissection may interfere with the operative radicality and might result in metastatic lymph nodes being overlooked and left in situ. PATIENTS AND METHODS: 50 consecutive patients had an extended extrafascial rectal excision resection for cancer. In 19 of the 50 patients activated carbon particles (CH40) were injected preoperatively into the rectum. The autonomic nerves with surrounding connective tissue were serially dissected from the resected specimen, carefully sliced at 5-mm intervals and collected for histological study. Lymph nodes along the axial and lateral drainage routes were examined, and the inclusion of CH40 in the nodes was microscopically studied according to the site of CH40 injection. RESULTS: Lymph nodes within the connective tissue along the dissected autonomic nerves were demonstrated in 47 of the 50 cases. Two of 50 cases had positive nodes along preaortic plexus or pelvic plexus, and a case with nodal involvement along the pelvic plexus had poor prognosis in spite of nerve excision. CH40 when injected into the rectum above the peritoneal reflection was demonstrated in the vast majority of the axial nodes, while in only one lymph node along the preaortic plexus when injected in the rectum above the peritoneal reflection. On the other hand when injected in the rectum below the peritoneal reflection, CH40 was demonstrated both in axial and lateral nodes as well as in lymph nodes along bilateral pelvic plexuses, right hypogastric nerve, superior hypogastric plexus, preaortic plexus and mesenteric plexus as well. CONCLUSIONS: When located above the peritoneal reflection a rectal carcinoma will spread preferentially along the upper axial route, while a carcinoma located below the peritoneal reflection will also spread laterally and along the autonomic nerves. It was inferred that lymphatic flow along the autonomic nerves came up from the rectum below the peritoneal reflection mainly through a so-called lateral ligament but its clinical significance was negligible. Therefore doing TME with autonomic nerve preservation does not imply a less radical surgery from the point of lymphatic spread.

Perineural invasion in pancreatic cancer

INTRODUCTION

Perineural invasion is regarded as a factor associated with local recurrence of pancreatic cancer.

AIM

To examine perineural invasion of pancreatic cancer pathologically and clinically.

METHODOLOGY

In 24 cases of surgically resected pancreatic cancer, correlations among the degree of perineural invasion, differentiation, interstitial connective tissue, lymph node metastasis, and survival rate were examined. Consecutive 5-microm serial sections (n = 1072) were made in six cases that showed characteristic mode of perineural invasion.

RESULTS

Perineural invasion was observed in 17 cases (70.8%; ne0-7; ne1-6; ne2-9; and ne3-2 cases). Perineural invasion was absent in three of five cases of papillary carcinoma, but was observed in 12 of 14 cases of moderately differentiated carcinoma. The survival rate for ne0 was better than that of the other groups, with the 3-year survival rate being 57.1%. Perineural cancer glands had developed discontinuously in two cases.

CONCLUSIONS

Perineural invasion is an important prognostic factor in pancreatic cancer, increasing as the cancer becomes undifferentiated. Even if there are no cancer cells at the margin of the pancreas at the time of surgery, the cancer cells may spread further to the noncancerous pancreas or retroperitoneum. Sufficient dissection of the neural plexus or intraoperative radiation may be required.

Lateral ligament: its anatomy and clinical importance

Since Miles proposed abdominoperineal excision as a radical surgery for rectal cancer in 1908, surgeons have recognized the lateral ligament in the pararectal space of their patients and attached clinical importance to it, although anatomists did not describe any such configuration in cadavers. By analyzing an experience of 421 lower rectal cancer cases at the Cancer Institute Hospital in Tokyo, discussion of the lateral ligament was focused on its relationship to the fascial arrangements in the pelvis, the pelvic autonomic nervous system, and the lymphatic drainage of the rectum. The lateral ligament is not an anatomical term, but a clinical or surgical one. It exists in a living pelvis as a condensation of connective tissue around the middle rectal artery and is divided into two segments by the inferior hypogastric nerve plexus inside it and the visceral endopelvic fascia around it. The lateral ligament is a pathway of blood vessels and nerve fibers toward the rectum and lymphatic vessels from the lower rectum toward the iliac lymph nodes. Therefore, the lateral ligament plays a critical role in surgery for lower rectal cancer in two respects: the anatomic extent of resection for curing rectal cancer, and the preservation of sexual function.

Autonomic nerve plexus involvement and prognosis in patients with rectal cancer

BACKGROUND

A detailed knowledge of the fundamental basis for cancer involvement of the autonomic nerve plexus and the outcome of patients with such cancer foci is important when considering nerve-preserving surgery for rectal cancer.

METHODS

Extrarectal autonomic nerve plexuses were obtained from 61 patients with advanced rectal cancer who were undergoing extended resection of the rectum with the associated nervous system. The specimens were sectioned totally so that any indirect cancer involvement of the extrarectal autonomic nerves and/or the surrounding tissue could be detected.

RESULTS

Autonomic nerve plexus involvement was observed in nine patients: none of 25 with Dukes A/B, six of 28 with Dukes C and three of eight with Dukes 'D' lesions. Five of 26 patients with nodal involvement in the pararectal area had such foci, and four of eight patients with nodal involvement further from the primary tumour. Furthermore, of the nine patients with nerve plexus involvement, seven had extranodal cancer deposits in the mesorectum. The 3-year survival rate of patients with nerve plexus involvement was 33 per cent, while it was 83 per cent in those without such disease.

CONCLUSION

Nerve plexus involvement was observed in direct proportion to the extent of cancer spread to the mesorectum, and the prognosis of patients with such disease was unfavourable. Further investigation is needed to better identify those patients who would clearly benefit from an en bloc resection of the autonomic nerves.