Accurate specimen preparation and examination is mandatory to detect lymph nodes and avoid understaging in colorectal cancer

Reliability and Effectiveness of GEWF Solution in the Identification of Lymph Nodes in Specimens of Colorectal Carcinoma

Lymph node status is pivotal in the staging process of cancer. With regards to colorectal cancer, lymph node retrieval is always laborious. Sometimes, it is also a challenge to recover a minimum of 12 lymph nodes from the pericolorectal tissue. Among many proposed adjunctive solutions, GEWF solution (glacial acetic acid, ethanol, distilled water, and formaldehyde) has been introduced recently and suggested to be superior. To further evaluate its efficiency, the pericolorectal tissue, which has been reexamined extensively in the conventional condition, was refixed into GEWF solution in this study. More lymph nodes were found in 75% (n = 6) of the 8 experimental cases, and 50% (n = 4) of them had 12 or more yielded lymph nodes eventually. In addition, no adverse influences on the expressions of immunohistochemical and special stains were seen. These data support the reliability and effectiveness of GEWF solution in improvement of lymph node yield.

Lymph node harvest in colon cancer specimens depends on tumour factors, patients and doctors, but foremost on specimen handling

There are good indications that the number of lymph nodes found in the specimen after resections for colon cancer somehow has a bearing on prognosis. Many factors have been reported in the literature to influence lymph node retrieval. We wanted to assess these closer with special focus on the pathology handling process in our own practice. A range of international literature was reviewed to study what has been found to influence lymph node harvest. A questionnaire was sent to 13 renowned national and international institutions to explore their handling of the colon cancer specimens to obtain a histological diagnosis. A retrospective, hospital audit was undertaken to examine if the number of lymph nodes and staging after examinations of the specimens varied between individual pathologists. In the literature, tumour and patient characteristics, as well as the surgeon and the pathologist, are found to be influential, but it is difficult to ascertain which ones are truly essential. Fat solvents were found by several to increase the lymph node yield, although some also opposed this finding. Our questionnaire showed some variations in the routines of each Department. A junior pathologist was more likely to inspect the specimen first hand and not more than half employed specific lymph node detection strategies while three of 13 did not seek a minimum number of lymph nodes. Still every department had implemented a standard procedure for such examinations. The internal audit showed without doubt that the devotion of the pathologist secured significantly more lymph nodes from the specimen and this may also have detected more stage III cancers. Several tumour and individual patient characteristics, surgical approach and specimen handling may influence lymph node yield and theoretically, TNM staging. Our investigation specifically suggests that tissue handling by pathologists may be a prominent factor in lymph node harvest from colon cancer specimens.

The total mesorectal excision specimen for rectal cancer: a review of its pathological assessment

Total mesorectal excision (TME) refers to the surgical removal of the complete perirectal soft tissue envelope, using sharp instruments under direct vision, and has become the contemporary standard of care for patients with rectal cancer. Pathologists play a key role in the evaluation of these specimens, including the quality assurance of surgical performance, as well as evaluation of the circumferential radial margin (CRM). While the latter is the most significant predictor of local recurrence, the quality of the excised mesorectum is another important factor in assessing the risk of local recurrence in patients with a negative CRM. Since proper pathological assessment of the TME specimen provides important prognostic information, as well as critical feedback to surgeons regarding technical performance, it is important to have adequate guidelines for the macroscopic handling of these specimens. The CLASSICC study of the Medical Research Council in the United Kingdom, as well as the Dutch TME trial have introduced a new standard for the pathological assessment of TME specimens, including an approach that involves assessment in both the fresh and fixed states, at least 48 hours of fixation of an intact specimen, with observations made on both the external appearance and cross-sectional slices. This article reviews the pathological assessment of the TME specimen, including basic definitions, current international guidelines, an approach to evaluating the mesorectum and a discussion of special issues relating to margins, lymph node retrieval and effects of neoadjuvant therapy.

Number of lymph nodes examined and prognosis of TNM stage II colorectal cancer

The diagnosis of a lymph node-negative colorectal carcinoma should imply a good prognosis; however, the outcomes for TNM stage II patients remain variable. Few studies have examined the relationship of the number of lymph nodes examined to the prognosis of this stage. The aim of this study was to determine whether the number of lymph nodes examined has an effect on prognosis of a relatively large sample of patients undergoing curative surgery for stage II colorectal cancer at a single institution. Data on patients who underwent surgery for colorectal cancer between January 1980 and April 2000 were prospectively collected in a database. Patients with TNM stage II or stage III tumours who were treated with curative intent were removed. Patients over 80 years of age were excluded from the survival analysis. Survival comparisons were made using Kaplan-Meier curves and the log-rank test. Multivariate analysis was performed using a Cox regression model. A total of 625 cases of TNM stage II cases and, for comparison purposes, 415 stage III cases, were analysed. Lymph node retrieval in stage II cases was affected by the patient's age (P=0.04) and gender (P=0.02), tumour grade (P<0.0001), tumour site (P<0.0001), and necessity to carry out extended resection (P<0.0001). In stage III cases, lymph node retrieval was affected by patient age (P<0.0001), tumour grade (P=0.02), and tumour site (P=0.002). Decreased lymph node detection was associated with increasing hazard ratios among the 480 TNM stage II patients under 80 years of age, but not among the 345 patients with TNM stage III tumours. Five year survival rate for patients with stage III tumours with only 1-3 positive lymph nodes (52.6%) was similar to that of patients with stage II tumour who had nine or fewer lymph nodes examined (51.3%). These results demonstrate that the prognosis of TNM stage II colorectal cancer is dependent on the number of lymph nodes examined. Patients with few nodes examined have a poorer prognosis. It is possible that a smaller number of lymph nodes examined reflects a diminished immune response. It can be presumed that those patients with stage II tumour with only a few nodes examined should be offered postoperative chemotherapy on a routine basis.

Metastatic lymph node size and colorectal cancer prognosis

BACKGROUND

Colorectal cancer patients with lymph node metastasis constitute a heterogeneous population with variable prognoses. In this study, my colleagues and I propose a simpler lymph node (LN) staging system for colorectal cancer.

STUDY DESIGN

Four-hundred and twenty-three consecutive colorectal cancer patients were studied. Of these, 36 were excluded because another carcinoma was present. The remaining 387 patients entered the TNM staging analysis. In the survival analysis, 76 patients with distant metastasis were excluded and the remaining 311 patients (LN(-) = 204 and LN(+) = 107) were studied. The diameter of the largest metastatic LN (MLN) was measured on histopathological slides. After examination of various cutpoints and survival outcomes, patients with MLNs were classified into n1 (< or = 9 mm) and n2 (> or = 10 mm) groups, according to size of MLNs (n-stage).

RESULTS

Using disease-free survival (DFS) and overall survival (OS) as outcomes, patients were separated into significant prognostic groups by MLN size (univariate, p < 0.0001) (5-year survival, DFS: n0 = 91.5%, n1 = 62.2%, and n2 = 34.4%; OS: n0 = 85.1%, n1 = 63.5%, and n2 = 42.5%) and International Union Against Cancer/American Joint Committee on Cancer (UICC/AJCC) (N-stage) (univariate, p < 0.0001) (5-year survival, DFS: N0 = 91.5%, N1 = 60.5%, and N2 = 36.8%; OS: N0 = 85.1%, N1 = 65.3%, and N2 = 38.0%). But in patients with fewer than 15 LNs examined (n = 31), only the new nodal stage stratified patients into significant groups (OS: p = 0.003 and DFS: p = 0.001). Only the UICC/AJCC N-stage subcategories were further split into significant prognostic groups by MLN size (UICC/AJCC N1: DFS, p = 0.048 and OS, p = 0.11; N2: DFS, p = 0.04 and OS, p = 0.04). n-stage was an independent important factor both in the DFS and OS in multivariable analysis.

CONCLUSIONS

MLN size is a strong prognostic variable in colorectal carcinoma. This new metric may help clinicians treating colorectal cancer patients, but additional studies are required before clinical application.

Sentinel lymph node mapping in colon and rectal cancer: its impact on staging, limitations, and pitfalls

Sentinel lymph node (SLN) mapping has been widely applied in the staging of solid neoplasms including colon and rectal cancer. Since the first reported feasibility study in 1997, there have been numerous publications validating SLN mapping as a highly accurate and powerful upstaging technique for colon and rectal cancer. In addition to refining the technical aspects of this procedure, these studies have investigated the use of other tracers and operative techniques, while determining the indications, limitations, and pitfalls of SLN mapping in patients with colorectal cancers. This chapter reviews the rationale for performing SLN mapping for the accurate staging of colon and rectal cancers, and provides a brief review of the historical background of the development of the procedure. Landmark publications, which have contributed to the current status of the technique, are discussed. We will focus on the technical details of the procedure, and on the pathological evaluation of the specimen and the SLNs. The various tracers and techniques of SLN mapping in colon and rectal cancer will be discussed. We have performed SLN mapping in more than 240 consecutive patients over the past 7 years. The success rates for identifying at least one SLN for colon and rectal cancer were 100% and 90.6%, respectively. The accuracy rates were 95.8% and 100%, respectively. In terms of upstaging, 32.3% of colon cancer patients with nodal metastases and 16.7% of rectal patients with nodal metastases were upstaged by the detection of micrometastases found in the SLNs only. Finally, we will also discuss the current role as well as the future research directions for SLN mapping in colon and rectal cancer.

Nodal staging of colorectal carcinomas and sentinel nodes

This review surveys the staging systems used for the classification of colorectal carcinomas, including the TNM system, and focuses on the assessment of the nodal stage of the disease. It reviews the quantitative requirements for a regional metastatic work up, and some qualitative features of lymph nodes that may help in the selection of positive and negative lymph nodes. Identification of the sentinel lymph nodes (those lymph nodes that have direct drainage from the primary tumour site) is one such qualitative feature that is claimed to allow the upstaging of colorectal carcinomas via an oriented, enhanced pathological work up. Current evidence in favour of a change in the requisite of assessing as may lymph nodes as is possible, and concentrating the efforts on only a selected number of lymph nodes, is weak.

Hepatic resection for colorectal metastases: can preoperative scoring predict patient outcome?

A retrospective study was performed to define patient selection, safety, and efficacy of hepatic resection for colorectal metastases. The recently proposed preoperative clinical risk score (CRS) for selection of patients for surgery was also assessed. In all, 146 consecutive hepatic resections in 137 patients operated in the period between 1977 and 1999 were studied. Of these patients, 113 were classified into five CRS groups. Perioperative mortality was 1.4% (2 patients; no death in 120 patients operated after 1985) and morbidity was 38%. Five-year actuarial survival (perioperative mortality included) was 29% (median 37 months), and actual 5-year survival was 25% (17/69 patients). Patients operated after 1995 lived longer than those operated before 1995. Multiple regression analyses identified preoperative carcinoembryonic antigen CEA <100 mg/L, nodal status at resection of primary tumor, and R0 vs. R1/R2 resection as prognostic parameters. CRS grouping had prognostic importance. The relative risk (hazard rate) of tumor recurrence in patients with CRS 3-4 was 2.1, compared to that of patients with CRS 0-2. Five-year actuarial survival in the two groups was 12% and 40%, respectively. Fourteen of 15 long-term survivors (>5 years) classified by the CRS system had CRS of 2 or less. Resection for colorectal liver metastases is safe, and long-term survival rates are acceptable. CRS predicts patient outcome, but the clinical role in patient selection will have to be defined in prospective studies.

Is there a minimum number of lymph nodes that should be histologically assessed for a reliable nodal staging of T3N0M0 colorectal carcinomas?

BACKGROUND AND OBJECTIVES

Because of the existing controversy, we searched for a cutoff value for the number of lymph nodes (LNs) to be examined in order to establish a reliable node-negative stage in colorectal carcinomas (CRCs).

METHODS

From the SEER database, 8,574 T3N0M0 first, single, histologically confirmed, surgically treated CRCs, with at least 1 LN examined histologically, were considered. As a first approach, the relationships between number of examined LNs and 5- and 10-year overall survival (OS) rates, computed by the Kaplan-Meier method, were assessed. Next, multivariate analysis was performed; a proportional hazards model was fitted to the data and used to obtain a smoothed plot of the martingale residuals vs. the number of negative LNs.

RESULTS

Both OS rates displayed an improvement with an increase of number of LNs examined. The smoothed plot of the martingale residuals against the number of negative LNs was reasonably linear.

CONCLUSIONS

Both approaches suggest that there is no cutoff value for the number of LNs to be examined for an adequate nodal staging; for a reliable pN0 staging, as many LNs should be assessed as possible. However, qualitative features of lymph nodes (e.g., those identified by sentinel lymphadenectomy) may alter this recommendation.

The influence of nodal size on the staging of colorectal carcinomas

AIMS

The reliable identification of node negative colorectal carcinomas (CRCs) has often been linked to the histological examination of a minimum number of lymph nodes. The sizes of the lymph nodes, their metastatic status, and their number were investigated to establish whether these parameters are related, and whether their relation could help in determining the adequacy of staging.

METHODS

One thousand three hundred and thirty four negative lymph nodes, 189 metastatic lymph nodes, and 43 pericolonic/perirectal tumour deposits measuring > or = 3 mm from 60 node positive and from 63 node negative patients with CRC were assessed for size.

RESULTS

The mean size (SD) of these structures was 4.5 (2.7) mm. The lymph nodes were significantly larger in the CRCs with metastatic nodes (4.7 v 4.3 mm). Involved nodes were significantly larger than negative nodes (6.3 v 4.2 mm), despite the fact that the largest node was < or = 5 mm in one third of node positive CRCs. The examination of the seven largest nodes could have adequately staged 97% of node positive CRCs and 98% of all CRCs.

CONCLUSIONS

The nodal staging of CRCs is dependent not only on the number of lymph nodes investigated, but also on qualitative features of the lymph nodes assessed, including their size. Lymph nodes are not equivalent and any study neglecting this fact will give grounds for error in the recommendation of a minimum number of nodes for the reliable determination of node negative CRCs. Although pathologists should aim to recover all nodes, a negative nodal status based on only seven nodes can be reliable.

Patterns of lymphatic spread in rectal cancer. A topographical analysis on lymph node metastases

The presence of lymph node (LN) metastases is the most important prognostic factor in rectal cancer. The exact LN status can only be known when an extended lymph node dissection (LND) has been performed, a process not routinely performed. If the likelihood of LN metastases can be more accurately assessed preoperatively, then an optimal multimodality treatment plan can be established. 605 patients with primary rectal cancer operated upon with wide LND (D3 level) were analysed for LN metastases combining topographical localisation and morphological features of the tumour. More distal rectal tumours tend to more LN metastases and more lateral lymphatic spread. Tumours >or=3 cm show more LN metastases compared with those smaller than 3 cm. Depth of bowel wall invasion is strongly related to the presence of LN metastases. The peritoneal reflection has no discriminating role in the mode of spread. Intra-operative assessment by the surgeon for presence of LN metastases is not reliable. When localisation, depth of bowel wall invasion and diameter of a rectal tumour are known, a likelihood of LN metastases can be assessed pre-operatively, not intra-operatively.

GEWF solution

BACKGROUND

Lymph node status is an important prognostic factor in the staging of colorectal carcinoma. Several adjunctive solutions have been used to increase the yield of pericolic lymph nodes from colorectal cancer resection specimens.

METHODS

During 1998 at the Grey Bruce Regional Health Centre (Owen Sound, Ontario), 67 colonic resections were performed for colorectal cancer. Lymph nodes were identified using GEWF solution (glacial acetic acid, ethanol, distilled water, and formaldehyde) in 35 cases, and by the conventional method of sectioning, inspection, and palpation in 32 cases.

RESULTS

There were no significant differences between GEWF and non-GEWF cases with respect to patient age, length of resection, size of tumor, tumor histologic type, tumor differentiation, or depth of tumor penetration into the bowel wall. Use of GEWF led to a significant increase in the number of lymph nodes found (10.2 +/- 4.9 per case) compared with non-GEWF cases (6.8 +/- 3.9 per case) (P =.002). In GEWF cases 358 lymph nodes were identified, 82 with metastases, whereas in the non-GEWF cases 218 lymph nodes were found, 41 with metastases. The size of positive lymph nodes in the GEWF group (0.5 +/- 0.2 cm) was significantly smaller than in the non-GEWF group (0.7 +/- 0.4 cm) (P =.046). A greater percentage of positive lymph nodes in the GEWF cases (49/82, 60%) were 0.5 cm or smaller compared with the non-GEWF cases (17/41, 41%).

CONCLUSIONS

GEWF increases the yield of lymph nodes recovered from colorectal cancer specimens and may lead to improved staging of this cancer; it is inexpensive and simple to use.

Pathologic evaluation of sentinel lymph nodes in colorectal carcinoma

BACKGROUND

The identification of lymph node metastases in colorectal resection specimens is necessary for accurate tumor staging. However, routine lymph node dissection by the pathologist yields only a subset of nodes removed surgically and may not include those nodes most directly in the path of lymphatic drainage from the tumor. Intraoperative mapping of such sentinel lymph nodes (SLNs) has been reported in cases of melanoma and breast cancer. We applied a similar method to cases of colorectal carcinoma, with emphasis on the pathology of the SLNs.

METHODS

Eighty-three consecutive patients with colorectal carcinoma were evaluated after intraoperative injection of 1 to 2 mL of 1% isosulfan blue dye (Lymphazurin) into the peritumoral subserosa. Blue-stained lymph nodes were suture-tagged by the surgeon within minutes of the injection for identification by the pathologist, and a standard resection was performed. Designated SLNs were sectioned at 10 levels through the block; a cytokeratin immunostain (AE1) was also obtained. To evaluate the possibility that increased detection of metastases in the SLN might be solely due to increased histologic sampling, all initially negative non-SLNs in the first 25 cases were sectioned also at 10 levels.

RESULTS

Sentinel lymph nodes were identified intraoperatively in 82 (99%) of 83 patients and accounted for 152 (11.9%) of 1275 lymph nodes recovered, with an average of 1.9 SLNs per patient. A total of 99 positive lymph nodes (38 positive SLNs and 61 positive non-SLNs) were identified in 34 node-positive patients. The SLNs were the only site of metastasis in 17 patients (50%), while 14 patients (41%) had both positive SLNs and non-SLNs. Three patients (9%) had positive non-SLNs with negative SLNs, representing skip metastases. In patients with positive SLNs, 91 (19%) of 474 total lymph nodes and 53 (12%) of 436 non-SLNs were positive for metastasis. In patients with negative SLNs, 8 (1%) of 801 total lymph nodes and 8 (1.2%) of 687 non-SLNs were positive for metastasis. Multilevel sections of 330 initially negative non-SLNs in the first 25 patients yielded only 2 additional positive nodes (0. 6%). All patients with positive SLNs were correctly staged by a combination of 4 representative levels through the SLN(s) together with a single cytokeratin immunostain.

CONCLUSIONS

Intraoperative mapping of SLNs in colorectal carcinoma identifies lymph nodes likely to contain metastases. Focused pathologic evaluation of the 1 to 4 SLNs so identified can improve the accuracy of pathologic staging.

Sentinel lymph node mapping in colorectal cancer--a review

Sentinel lymph node (SLN) mapping has been found to be highly effective in correctly predicting the nodal status for melanoma and for breast cancer. This study shows that SLN mapping also is highly successful in colorectal cancer, posing minimal cost and no complications. The procedure accurately determines the presence or absence of nodal micrometastasis in more than 96% of cases. This article reviews the in vivo and ex vivo techniques for SLN mapping in colorectal cancer, along with its limitations and pitfalls.

Limitations with light microscopy in the detection of colorectal cancer cells

PURPOSE

The failure of light microscopy to predict individual patient survival accurately in pStage I and II colorectal carcinoma can hinder planning postoperative therapy and follow-up. This study was designed and conducted in two parts to assess the influence of relative sensitivity of the light microscope on the pathologist's ability to detect malignant cells in lymph nodes.

METHODS

The first part of the study examined the issue of sampling error as a fraction of the number of lymph node sections examined by asking the question, "Does increasing the number of sections (sampling) taken from the block increase tumor cell detection in a lymph node?" Three levels of five sections 4 to 5 microm thick separated by 15 to 20 microm were obtained from each of 494 blocks from 173 cases of pStage I and II colorectal carcinoma. A total of 1,721 lymph nodes were examined. Sections from each level were stained with hematoxylin and eosin and for the expression of cytokeratin. The second part of the study examined the relative sensitivity of the light microscope to detect tumor cells in a lymph node. To simulate lymph nodes, cell blocks were made that contained 10(6) or 10(7) mononuclear cells admixed with increasing numbers of SW480 tumor cells (0, 50, 10(2), 5 x 10(2), 10(3), and 5 x 10(3)). Three pathologists independently examined sections from ten control and ten experimental blocks.

RESULTS

Results from the first part of the study demonstrated cytokeratin-positive cells in 278 lymph nodes from 102 of 172 (59 percent) cases. These cells were identified in the first level in 177 (64 percent) as compared with the second or third level or both in 101 (36 percent) of the lymph nodes. Results from the second part of the study demonstrated an overall sensitivity of light microscopic examination of hematoxylin and eosin-stained sections to be approximately 23 percent, representing tumor cells correctly detected in 7 sections of the 30 sections containing tumor cells. The overall specificity was 87 percent or 26 sections correctly classified as lacking tumor cells of a possible 30. Immunohistochemical staining for cytokeratin expression improved sensitivity of the light microscope to detect tumor cells to 18 of 30 (60 percent) and the specificity to 30 of 30 (100 percent).

CONCLUSION

This study demonstrates several sources of variability that can induce errors in pathologic staging. These include 1) inadequate section, i.e., sampling, of lymph nodes, 2) use of only hematoxylin and eosin-stained sections, 3) samples with tumor cells below the level of detection sensitivity of the light microscope, and 4) observer variability.

Accurate lymph-node detection in colorectal specimens resected for cancer is of prognostic significance

PURPOSE

Lymph-node involvement is the most important prognostic factor in colorectal cancers. Many staging systems adopted node status as a parameter of tumor classification. However, the number of identified and positive glands varies across articles, depending on specimen examination. There is a consistent risk of substaging tumors and undertreating patients. Aim of this study was to investigate the prognostic significance of different pathologic methods.

METHODS

Eight hundred one patients who underwent curative resection of colorectal cancer entered the study and were divided into two groups. In Group 1 the specimen was "en bloc" fixed, and nodes were identified by sight and palpation. In Group 2 the mesentery of the excised specimen was dissected away from the bowel, stretched, and pinned to cork board. The mesenteric segment surrounding the origin of principal vessels was divided from the segment surrounding the colic vessels. All specimen segments were fixed, node identification being performed by sight and palpation. Examined and positive nodes were recorded, and metastatic rate and incidence was calculated in the two groups. Patients were classified with use of different staging systems. Survival rates were calculated, related to tumor stage, and compared statistically. Pathologic procedures were included in a multivariate analysis.

RESULTS

A significantly higher number of detected and positive nodes and metastatic rate (37.5 vs. 30.2 percent; P < 0.05) were observed in Group 2; 45.2 percent of Group 2 and 25.3 percent of Group 1 cases had more than three positive nodes (P < 0.05). In Group 2 several patients shifted from earlier to more advanced stages compared with Group 1 cases. Five-year and ten-year survival rates were significantly higher (P = 0.04) in Group 2 (81.5 and 77.2 percent) than in Group 1 (76.7 and 61.5 percent), mostly in patients with TNM Stage N0. Survival analysis related to Astler and Coller's and Tang's classifications confirmed such features. Higher rates of local recurrences and distant metastases were found in Group 1, particularly if related to node status (P < 0.05). Multivariate analysis demonstrated the pathologic method is an independent prognostic factor.

CONCLUSIONS

This study demonstrates the prognostic impact of specimen examination. Inaccurate methods could down-stage the tumor and exclude the patient from adjuvant therapies, with detrimental effects on the outcome of the case.

Prognostic factors in colorectal cancer. Literature review for clinical application

PURPOSE

Identification of prognostic factors is a primary basis for planning the treatment and predicting the outcome of patients with colorectal cancer. Reviewing studies from the literature performed using univariate and multivariate analyses and their own study, the authors critically discuss the prognostic value of the clinicopathologic parameters of the tumor.

METHODS

Among 853 patients with colorectal tumors seen at the Department of Clinical Surgery of the Catholic University of Rome, Italy, 690 cases that were curatively resected the study. Overall survival rate, related to the clinicopathologic variables, was calculated, and univariate and multivariate analyses were performed.

RESULTS

Five-year and ten-year overall survival rates were 70 and 55 percent, respectively. Univariate and multivariate analyses showed that node involvement, distant metastases, bowel obstruction, and patient gender are factors independently related to outcome.

CONCLUSIONS

Data from the literature and the present study suggest that only a few clinical parameters, particularly bowel obstruction, and some pathologic factors (tumor stage, vessels invasion, and tumor ploidy) are related to patient survival rate and are the most reliable prognostic criteria. In prospective clinical studies, any other new pathologic or molecular factors should be matched with these parameters to confirm their value in outcome prediction.

Intraoperative radiation therapy in integrated treatment of rectal cancers. Results of phase II study

PURPOSE

Risk of local recurrence of rectal cancer remains high despite extensive therapeutic strategies, many of which have been tried to achieve better local control (i.e., external beam radiation therapy (EBRT)). Recently, intraoperative radiation therapy (IORT) has been introduced in clinical protocols to boost the areas at risk of local recurrence.

METHODS

Between April 1990 and December 1995, 44 patients with "high risk" (T3,N0-2 primary tumors) extraperitoneal rectal tumors and 24 patients with "locally advanced" (2 T3,N3 and 11 T4,N0-3 primary tumors; 11 local recurrences) tumors entered a protocol that included preoperative EBRT (38 Gy), surgery plus IORT (10 Gy) in the high-risk group, and preoperative EBRT (45-48 Gy) and concomitant computerized tomography (5-fluorouracil plus mitomycin C), surgery plus IORT (10-15 Gy), and postoperative adjuvant computerized tomography (5-fluorouracil plus folinic acid) in the locally advanced group.

RESULTS

In the high-risk group, acute Grade 3 (Radiation Therapy Oncology Group scale) skin toxicity, attributable to preoperative treatment, involved one patient (2.2 percent); among locally advanced cases, Grade 3 hematologic toxicity was observed in one patient (4.1 percent). Treatment was discontinued in no patients. On average, IORT prolonged surgery by 48 minutes. There was no mortality. Four anastomotic leakages, one pelvic infection, and five wound infections were observed. No chronic IORT-related toxicity occurred. After mean follow-up periods of 28.3 and 25.9 months, 41 and 15 patients in the high-risk and locally advanced groups, respectively, are alive and disease-free. In one high-risk patient, an anastomotic recurrence occurred. In four patients with locally advanced tumors (1 T4 primary, 3 local recurrences) an unresectable tumor relapse developed locally. Distant metastases occurred in two high-risk patients and in eight patients with a locally advanced tumor. Three-year actuarial survival was 100 percent in both high-risk and locally advanced primary tumors and 68.2 percent in local recurrences.

CONCLUSIONS

Results of this study suggest that multimodal treatment (including IORT) in rectal cancer is safe, has no significant increase of mortality and morbidity, and also shows a trend for local improvement. A longer term follow-up and larger numbers of patients could demonstrate the therapeutic efficacy of IORT in rectal cancer.

Prognostic significance and surgical management of locoregional lymph node metastases in papillary thyroid cancer

We studied the records of 342 patients with papillary thyroid carcinoma out of a total of 728 thyroid cancer patients treated at the Medical School of Hannover (MHH) from 1972 through 1992. The comprehensive data-abstracting forms were designed, and the acquired information was coded, stored, maintained, and evaluated by the Clinical Cancer Registry of the MHH. A total of 160 patients (46.8%) initially had lymph node metastases (N1 status). The N status significantly influenced recurrence (p < 0.00001) and survival (p < 0.00001). Excluding other risk factors developed by univariate and multivariate analysis, such as high age (age > 45 years, p < 0.001), tumor invasion (T4 tumor, p < 0.005), and distant metastases (M1, p < 0.001), lymph node metastases remained an independent, highly significant prognostic marker for more aggressive papillary thyroid cancer. N1 status did not influence survival of patients with T4 tumor but did influence those with T1-T3 status (p < 0.001). The influence of N1 status remained significant in patients older (p < 0.001) and younger (p < 0.05) than 45 years of age. Systematic compartment-oriented dissection of lymph node metastases improved survival (p < 0.005, T1-T3) and recurrence (p < 0.00001, T1-T3) especially in patients with T1-T3 tumors. In conclusion, lymph node metastases with a significant incidence at a young age and male sex had a substantial effect on survival and recurrence especially in those with tumor status T1-T3. Systematic compartment-oriented dissection of the lymph node metastases results in better survival and a lower recurrence rate.