Sphincter-sparing treatment for distal rectal adenocarcinoma

BACKGROUND

Studies suggest that the anal sphincter can be preserved in some patients with distal rectal adenocarcinoma (DRA), but this has not been validated in any prospective multi-institutional trial.

METHODS

To test the hypothesis that the anal sphincter can be preserved in some patients with DRA, the Cancer and Leukemia Group B and collaborators reviewed 177 patients who had T1/T2 adenocarcinomas < or = 4 cm in diameter, which encompassed < or = 40% of bowel wall circumference, and were < or = 10 cm from the dentate line. Of the 177 patients, 59 patients who were eligible for the study had T1 adenocarcinomas and received no further treatment; 51 eligible T2 patients received external beam irradiation (5400 cGY/30 fractions 5 days/week) and 5-fluorouracil (500 mg/m2 IV d1-3, d29-31) after local excision.

RESULTS

At 48 months median follow-up, 6-year survival and failure-free survival rates of the eligible patients are 85% and 78% respectively. Three patients died of unrelated disease. Two patients were treated for second primary colorectal tumors; both remain disease free (NED). Another eight patients died of disease, four with distant recurrence only. One T1 patient is alive with distant disease. Two T1 and seven T2 patients experienced isolated local recurrences; all underwent salvage abdominoperineal resection (APR). After APR, one T1 and four of seven T2 patients were NED at the time of last visit (2-7 years). One T1 patient died of local and distant disease. Three of seven T2 patients died with distant disease.

CONCLUSIONS

We conclude that sphincter preservation can be achieved with excellent cancer control without initial sacrifice of anal function in most patients. After local recurrence, salvage resection appears effective, but longer follow-up time of local and distant disease-free survival is advised before extrapolation to patients with T3 primaries.

Surgical margin in hepatic resection for colorectal metastasis: a critical and improvable determinant of outcome

OBJECTIVE

To update the analysis of technical and biologic factors related to hepatic resection for colorectal metastasis in a large single-institution series to identify important prognostic indicators and patterns of failure.

SUMMARY BACKGROUND DATA

Surgical therapy for colorectal carcinoma metastatic to the liver is the only potentially curable treatment. Careful patient selection of those with resectable liver-only metastatic disease is crucial to the success of surgical therapy.

METHODS

Two hundred forty-four consecutive patients undergoing curative hepatic resection for metastatic colorectal carcinoma were analyzed retrospectively. Variables examined included sex, stage of primary lesion, size of liver lesion(s), number of lesions, disease-free interval, ploidy, differentiation, preoperative carcinoembryonic antigen level, and operative factors such as resection margin, use of cryotherapy, intraoperative ultrasound, and blood loss.

RESULTS

Surgical margin, number of lesions, and carcinoembryonic antigen (CEA) levels significantly control prognosis. Patients with only one or two liver lesions, a 1-cm surgical margin, and low CEA levels have a 5-year disease-free survival rate of more than 30%. Disease-free interval, original stage, bilobar involvement, size of metastasis, differentiation, and ploidy were not significant predictors of recurrence. The pattern of failure correlates with surgical margin. Routine use of intraoperative ultrasound resulted in an increased incidence of negative surgical margin during the period examined.

CONCLUSIONS

Surgical resection or cryotherapy of hepatic metastasis from colorectal cancer is safe and curable in appropriately selected patients. Biologic factors, such as number of lesions and carcinoembryonic antigen levels, determine potential curability, and surgical margin governs the patterns of failure and outcome in potentially curable patients. Optimization of selection criteria and surgical resection margins will improve outcome.

Evaluation of common breast problems: guidance for primary care providers

The evaluation of common breast problems requires an assessment of the patient's risks and symptoms and a thorough physical examination. When indicated, appropriate imaging studies should be done, the patient should be referred to a surgeon or a breast specialist, and operative interventions should be used.

The National Cancer Data Base report on gastric cancer

BACKGROUND

Previous Commission on Cancer studies from the National Cancer Data Base (NCDB) have examined time trends in stage of disease, treatment patterns, and survival for selected cancers. The most current (1991) data for gastric cancer are described here.

METHODS

Three Calls for Data have yielded a total of 16,992 case reports of gastric cancer for 1985, 1986, and 1991, from hospital cancer registries across the U.S.

RESULTS

Gastric cancer was the 15th most frequent cancer reported to the NCDB. The proportion of all reported cancers that were gastric in the two time intervals studied were essentially the same. In 1991, 20.8% of the cases were reported in minorities. Only 46% of gastric cancer cases were staged by the American Joint Committee on Cancer (AJCC) system in 1985 to 86, compared with 77% in 1991. More advanced stages were reported for younger patients, but less advanced stages were noted in the Asian population. Of all patients reported, 41.4% had no reported cancer-directed surgery, 41.1% had partial or hemigastrectomy, and 6.7% had total gastrectomy. More extensive surgery was associated with patients with Stage III disease than with Stages I and II, as might be expected. Survival after treatment remained poor (5-year relative survival; 43% for Stage I, 37% for Stage II, 18% for Stage III, and 20% for Stage IV).

CONCLUSION

Improvements in treatment will emerge allowing survival to serve as a better guide for the quality of care in the future. In the interim, the frequency of American Joint Committee on Cancer staging in patient charts and the fraction of patients with Stages I and II as opposed to Stages III and IV disease (as a measure of prompt diagnosis) may serve as measure of how quickly these cancers are being diagnosed.

Wound recurrence following laparoscopic colon cancer resection. Results of the American Society of Colon and Rectal Surgeons Laparoscopic Registry

INTRODUCTION

Multiple case reports have suggested that laparoscopic resection of colon cancer may alter the pattern or incidence of cancer recurrence. All reports lack a significant denominator to evaluate the incidence of surgical wound recurrence. We hypothesized that wound recurrence incidence is not increased by laparoscopic resection of colon cancer.

METHODS

A prospective registry was initiated under the auspices of The American Society of colon and Rectal Surgeons, American College of Surgeons, and Society of American Gastrointestinal Endoscopic Surgeons in 1992. Patients having laparoscopic colon resection were voluntarily entered and followed until June 1995. Recurrences were evaluated by the primary surgeon and reported to the registry.

RESULTS

A total of 504 patients treated for cancer were identified in the registry. A minimum follow-up of one year was obtained for 480 of 493 evaluable patients (97.4 percent). Wound recurrence was identified in five patients (1.1 percent). Recurrence status was unknown in 18 patients (3.8 percent).

CONCLUSION

Wound recurrence rates appear to be low. Although length of follow-up is limited, patterns of recurrence from previous studies suggest that 80 percent of recurrences should have occurred within one year. Given the limitations of a Phase II study, the hypothesis that recurrence rate is low is supported. However, prospective randomized trials are needed to establish if any difference in wound recurrence rates after laparoscopic or open resection of colorectal cancer exists.

The National Cancer Data Base. Report on colon cancer

BACKGROUND

Commission on Cancer data from the National Cancer Data Base (NCDB) report time trends in stage of disease, treatment patterns, and survival for patients with selected cancers. The most current data (1993) for patients with colon cancer are described.

METHODS

Five calls for data yielded 3,700,000 cases of cancer for the years 1985 through 1993 from hospital cancer registeries across the U.S., including 36,937 cases of colon cancer from 1988 and 44,812 from 1993.

RESULTS

Interesting trends are as follows: (1) the elderly ( > 80 years) present with earlier stage disease than younger patients; (2) the National Cancer Institute recognized cancer centers have more patients with advanced disease than other types of hospitals; (3) all ethnic groups have generally similar stages of disease at presentation, except for African-Americans who have a slightly higher incidence of Stage IV disease; (4) the proximal migration of the primary cancer continues with 54.7% of primary colon cancer arising in the right colon in 1993 compared with 50.9% in 1988; (5) an interaction between grade and stage of cancer seems present; and (6) patients with Stage III colon cancer who received adjuvant chemotherapy had a 5% improvement in 5-year relative survival.

CONCLUSIONS

The NCDB data are useful for reporting what cancer treatments are being administered and what outcomes are occurring in the U.S. The data suggest an important biologic role for grade of cancer. They also suggest that African-Americans and other ethnic groups have the same outcome as non-Hispanic whites but that access to medical care may still be less. Finally, the utility of adjuvant therapy for Stage III colon cancer may just be beginning to be appreciated.

The National Cancer Data Base. Report on colon cancer

BACKGROUND

Commission on Cancer data from the National Cancer Data Base (NCDB) report time trends in stage of disease, treatment patterns, and survival for patients with selected cancers. The most current data (1993) for patients with colon cancer are described.

METHODS

Five calls for data yielded 3,700,000 cases of cancer for the years 1985 through 1993 from hospital cancer registeries across the U.S., including 36,937 cases of colon cancer from 1988 and 44,812 from 1993.

RESULTS

Interesting trends are as follows: (1) the elderly ( > 80 years) present with earlier stage disease than younger patients; (2) the National Cancer Institute recognized cancer centers have more patients with advanced disease than other types of hospitals; (3) all ethnic groups have generally similar stages of disease at presentation, except for African-Americans who have a slightly higher incidence of Stage IV disease; (4) the proximal migration of the primary cancer continues with 54.7% of primary colon cancer arising in the right colon in 1993 compared with 50.9% in 1988; (5) an interaction between grade and stage of cancer seems present; and (6) patients with Stage III colon cancer who received adjuvant chemotherapy had a 5% improvement in 5-year relative survival.

CONCLUSIONS

The NCDB data are useful for reporting what cancer treatments are being administered and what outcomes are occurring in the U.S. The data suggest an important biologic role for grade of cancer. They also suggest that African-Americans and other ethnic groups have the same outcome as non-Hispanic whites but that access to medical care may still be less. Finally, the utility of adjuvant therapy for Stage III colon cancer may just be beginning to be appreciated.

The National Cancer Data Base. Report on colon cancer

BACKGROUND

Commission on Cancer data from the National Cancer Data Base (NCDB) report time trends in stage of disease, treatment patterns, and survival for patients with selected cancers. The most current data (1993) for patients with colon cancer are described.

METHODS

Five calls for data yielded 3,700,000 cases of cancer for the years 1985 through 1993 from hospital cancer registeries across the U.S., including 36,937 cases of colon cancer from 1988 and 44,812 from 1993.

RESULTS

Interesting trends are as follows: (1) the elderly ( > 80 years) present with earlier stage disease than younger patients; (2) the National Cancer Institute recognized cancer centers have more patients with advanced disease than other types of hospitals; (3) all ethnic groups have generally similar stages of disease at presentation, except for African-Americans who have a slightly higher incidence of Stage IV disease; (4) the proximal migration of the primary cancer continues with 54.7% of primary colon cancer arising in the right colon in 1993 compared with 50.9% in 1988; (5) an interaction between grade and stage of cancer seems present; and (6) patients with Stage III colon cancer who received adjuvant chemotherapy had a 5% improvement in 5-year relative survival.

CONCLUSIONS

The NCDB data are useful for reporting what cancer treatments are being administered and what outcomes are occurring in the U.S. The data suggest an important biologic role for grade of cancer. They also suggest that African-Americans and other ethnic groups have the same outcome as non-Hispanic whites but that access to medical care may still be less. Finally, the utility of adjuvant therapy for Stage III colon cancer may just be beginning to be appreciated.

Ubiquitin fusion proteins are overexpressed in colon cancer but not in gastric cancer

A cDNA clone (AF3) encoding the ubiquitin A gene 52 amino acid extension fusion protein (UbA52) was isolated from a subtracted cDNA library of human colorectal carcinoma minus adjacent normal mucosa. In Northern hybridization the mRNA signal for UbA52 was greater in surgical samples of colonic carcinoma (T) than in paired adjacent normal (N) tissues in 24 of 29 cases (T/N = 3.4 +/- 0.5, P < 0.01). An oligonucleotide probe specific for only the 52 amino acid extension confirmed the overexpression of UbA52. In contrast, there was no overexpression of UbA52 mRNA in gastric cancer samples (n = 7, T/N = 1.0 +/- 0.3). The mRNA of several ribosomal proteins, and of another ubiquitin A gene fusion protein, UbA80, with an 80 amino acid extension of ribosomal protein S27a, have been reported to be over-expressed in colon cancer, but not as yet at the protein level. Using rabbit antisera to the ribosomal protein component S27a we demonstrate over-expression of S27a at the protein level in colonic (n = 5), but not gastric (n = 6) carcinomas. Therefore it is likely that both UbA80 and UbA52 are overexpressed in colon cancer, but not in gastric cancer.

Management and survival of patients with adenocarcinoma of the colon and rectum: a national survey of the Commission on Cancer

BACKGROUND

The Commission on Cancer (COC) of The American College of Surgeons periodically reviews criteria for evaluation of the care of patients with cancer related to diagnosis, treatment, rehabilitation, and follow-up. The COC annually performs a national survey of practices for several cancer sites.

STUDY DESIGN

Data collection forms for carcinoma of the colon and rectum were field-tested and then forwarded to participating hospitals. The study included a long-term survey to permit evaluation of five-year survival rates and a short-term survey to review current practices and time trends. Specific questions were asked concerning disease presentation, preoperative evaluation, surgical treatment, postoperative care, use of adjuvant therapy, and disease status at the last follow-up examination.

RESULTS

A total of 39,502 reports from 943 hospitals were analyzed, including 12,682 patients with carcinoma of the colon diagnosed in 1983, 16,527 patients with carcinoma of the colon diagnosed in 1988, 4,597 patients with carcinoma of the rectum diagnosed in 1983; and 5,696 patients with carcinoma of the rectum diagnosed in 1988. Patterns of care, including changes in presentation, diagnostic and therapeutic management, and survival rates, are presented. Specific data showing results for various ethnic groups are also included.

CONCLUSIONS

The distribution of cases by anatomic site was consistent with a hypothesis of rightward migration of colon carcinoma. Colon and rectal carcinomas in African-Americans were reported in more advanced stages and with corresponding decreases in survival rates. Some patterns of nonoptimal diagnostic use were noted. The increasing use of sphincter-sparing surgical alternatives for carcinoma of the rectum was evident. Adjuvant therapy was not widely used during this period. This study suggests evolving patterns of evaluation, increased preservation of continence, and improved but varying survival among ethnic groups. It further suggests that survival as measured across these 943 hospitals may be lower than that attained at some individual centers.

Laparoscopic Bowel Surgery Registry. Preliminary results

Laparoscopic surgery has evolved rapidly since 1989. The American Society of Colon and Rectal Surgeons, the Society of American Gastrointestinal Endoscopic Surgeons, and the American College of Surgeons Commission on Cancer jointly sponsored a registry to identify as early as possible the patterns of practice and acute complications of laparoscopic colectomy.

METHODS

Cases were voluntarily registered by community and academic surgeons. Information was entered in the EPI-5 database.

RESULTS

One thousand fifty-six cases were contributed by 118 surgeons; 763 patients were completed laparoscopically. The most common indication for surgery was cancer in 453 patients. The right colon (n = 364) and sigmoid (n = 294) were most frequently resected. Respondents felt adequate cancer resections were performed. Although several unique complications were noted, intraoperative complications were similar in type and frequency to open cases.

CONCLUSION

Laparoscopic colorectal surgery can be performed with acceptable complications. It remains unclear if this approach is adequate for long-term management of colon and rectal cancer.

The National Cancer Data Base report on gastric cancer

BACKGROUND

Previous Commission on Cancer studies from the National Cancer Data Base (NCDB) have examined time trends in stage of disease, treatment patterns, and survival for selected cancers. The most current (1991) data for gastric cancer are described here.

METHODS

Three Calls for Data have yielded a total of 16,992 case reports of gastric cancer for 1985, 1986, and 1991, from hospital cancer registries across the U.S.

RESULTS

Gastric cancer was the 15th most frequent cancer reported to the NCDB. The proportion of all reported cancers that were gastric in the two time intervals studied were essentially the same. In 1991, 20.8% of the cases were reported in minorities. Only 46% of gastric cancer cases were staged by the American Joint Committee on Cancer (AJCC) system in 1985 to 86, compared with 77% in 1991. More advanced stages were reported for younger patients, but less advanced stages were noted in the Asian population. Of all patients reported, 41.4% had no reported cancer-directed surgery, 41.1% had partial or hemigastrectomy, and 6.7% had total gastrectomy. More extensive surgery was associated with patients with Stage III disease than with Stages I and II, as might be expected. Survival after treatment remained poor (5-year relative survival; 43% for Stage I, 37% for Stage II, 18% for Stage III, and 20% for Stage IV).

CONCLUSION

Improvements in treatment will emerge allowing survival to serve as a better guide for the quality of care in the future. In the interim, the frequency of American Joint Committee on Cancer staging in patient charts and the fraction of patients with Stages I and II as opposed to Stages III and IV disease (as a measure of prompt diagnosis) may serve as measure of how quickly these cancers are being diagnosed.

Effect of membrane free fatty acid alterations on the adhesion of human colorectal carcinoma cells to liver macrophages and extracellular matrix proteins

Epidemiologic studies have linked diets high in animal fat with colon carcinogenesis. A number of animal tumor models have shown that diets rich in omega-3 fatty acids inhibit colon carcinogenesis while diets rich in omega-6 fatty acids promote tumor growth. This study examines whether modification of the membrane fatty acid composition of both moderately (CX-1) and poorly differentiated (MIP-101 and Clone A) human colorectal carcinoma cells alters their interaction with Kupffer cells and extracellular matrix proteins (collagen type IV, fibronectin and laminin). The cells were treated with 15-16 micrograms/ml of docosahexanoic acid (22:6, omega 3) or linoleic acid (18:2,omega 6). Gas chromatography showed significant alterations in the membrane fatty acid composition of the human colorectal cancer cell lines. Binding assays were performed by measuring adherence of 51Cr-labelled tumor cells to Kupffer cell monolayers or to immobilized proteins. Omega-3 treatment significantly decreased the Kupffer cell binding of only the CX-1 line while omega-6 treatment decreased binding of all three cell lines. In contrast both omega-3 and omega-6 treatment of MIP-101 cells decreased binding to the extracellular matrix proteins with the omega-6 effect being more pronounced. These results indicate that the binding characteristics of the colon cancer cells to both Kupffer cells and extracellular matrix proteins may be determined in part by the membrane fatty acid composition. Decreased adherence to extracellular matrix proteins may lead to increased cell motility and invasiveness. Since Kupffer cell binding precedes tumor cell phagocytosis and killing, decreased binding may improve tumor cell survival.

Clinical highlights from the National Cancer Data Base: 1995

The National Cancer Data Base, a joint project of the American Cancer Society and the American College of Surgeons Commission on Cancer, provides a mechanism for periodic assessment of hospital-based cancer patient care. From the National Cancer Data Base's annual summary, health care professionals can evaluate trends in patient care to make more efficient treatment decisions. This article provides a first look at highlights of the 1995 annual summary.

Biopsy of lesions of the colon, rectum, and anus

Most lesions of the colon, rectum, and anus can be biopsied only by using an endoscopic device. Adequate patient and bowel preparation, close communication with the pathologist, and meticulous handling and documentation of the specimen are required to ensure an accurate histologic diagnosis. Although somewhat controversial, most investigators agree that all but the smallest neoplasms of the colon and rectum should be excisionally biopsied when possible, incisionally biopsied when excision is not feasible, and destroyed if they are multiple, small, and not suspected of malignancy. Future studies will focus on the cellular biologic characteristics of the biopsy specimen to define more accurately the appropriate treatment plan and prognosis for patients.

The National Cancer Data Base report on colorectal cancer

BACKGROUND

Previous Commission on Cancer studies have examined time trends in stage of disease, treatment patterns, and survival for colorectal cancer. Reported herein are the most current 1993 National Cancer Data Base (NCDB) data on colorectal cancer.

METHODS

Two "calls for data," one in 1990 and one in 1991, have yielded a total of 71,560 colon cancer reports and 33,409 rectal cancer reports from hospital registries across the country.

RESULTS

For colon cancer, continuation of the time trend toward proximal migration was reported. For both colon and rectal cancer, American Joint Committee on Cancer staging was used increasingly as the standard of appropriate cancer diagnosis. Increased use of multimodal treatment was reported for both colon and rectal cancers. African-American and non-Hispanic white, low-income patients were reported to have later stages of both colon and rectal cancers.

CONCLUSIONS

The NCDB provides a useful longitudinal perspective on the diagnosis and treatment of colon and rectal cancers.

Human ribosomal protein L37 has motifs predicting serine/threonine phosphorylation and a zinc-finger domain

Ribosomal protein L37 mRNA is overexpressed in colon cancer. The nucleotide sequences of human L37 from several tumor and normal, colon and liver cDNA sources were determined to be identical. L37 mRNA was approximately 375 nucleotides long encoding 97 amino acids with M(r) = 11,070, pI = 12.6, multiple potential serine/threonine phosphorylation sites and a zinc-finger domain. The human sequence is compared to other species.

Intraoperative ultrasound imaging of the liver at the time of colorectal cancer resection

OBJECTIVES

To evaluate the accuracy of intraoperative ultrasound (IOUS) liver imaging at the time of primary colorectal cancer resection, which might eliminate incurable patients from adjuvant chemotherapy trials or permit earlier resection of curable metastases.

DESIGN

A prospective trial of routine IOUS liver imaging during resections of primary colorectal cancer. The rate of detection of occult metastases by IOUS imaging alone and the false-negative rate over 22.7 months of follow-up were determined.

SETTING

A tertiary care referral center in Boston, Mass.

PATIENTS

Fifty-five patients undergoing 56 operations for colorectal carcinoma between May 1990 and June 1992.

MAIN OUTCOME MEASURES

The rate of detection, by IOUS imaging alone, of otherwise occult hepatic metastases, the total number of patients with metastases detected at any time during follow-up, and the rate of false-negative findings on IOUS imaging and direct examination.

RESULTS

Occult hepatic metastases were detected by IOUS imaging alone in 5% of patients. Restriction of IOUS imaging to patients with T3 or T4 lesions or recurrent cancers would have identified all metastases and increased the detection rate to 10%. Occult metastases were detected by IOUS imaging alone in 12.5% of patients with T3, N0 lesions. The rate of false-negative findings on IOUS imaging was 13% overall, 0% for patients with T1 or T2 lesions, 3% for patients with node-negative findings, and 7% for patients with T3, N0 lesions.

CONCLUSIONS

The small increment in the detection of occult metastases by IOUS liver imaging does not warrant its use in all patients with colorectal cancer. Selective use in patients with T3 or T4 lesions or recurrent cancers increased the incremental gain in detection. The observed frequency of occult metastases in patients with T3, N0 lesions is sufficient to impact on results of adjuvant chemotherapy trials. Longer follow-up in more patients is needed to determine whether a negative IOUS study is an additional favorable prognosticator in patients with T1 and T2 lesions and node-negative findings.

Clinical highlights from the National Cancer Data Base: 1994

The National Cancer Data Base, a joint project of the American Cancer Society and the American College of Surgeons Commission on Cancer, provides a mechanism for periodic assessment of hospital-based cancer patient care. From the National Cancer Data Base's annual summary, health care professionals can evaluate trends in patient care to make more efficient treatment decisions. This article provides a first look at highlights from the 1994 annual summary.

The National Cancer Data Base. A mechanism for assessment of patient care

BACKGROUND

A mechanism for cancer patient care assessment was created. Data evaluations will enable clinicians and hospital staffs to appraise trends and compare their results with state, regional, and national figures.

METHODS

Data are collected annually on all forms of cancer from all parts of the country, including patient characteristics, tumor characteristics, first-course treatment, and follow-up.

RESULTS

Data for one or more years were received from a total of 1071 hospitals. This large, convenience sample of United States cancers included approximately 220,000 cases from 1985, 272,000 cases from 1988, and 409,000 cases from 1990. The seven most commonly reported cancers were breast, lung, prostate, colon, cervix, bladder, and rectum. In a 1993 National Cancer Data Base (NCDB) Annual Review, several disease categories and special subjects were analyzed, including colorectal, breast, and prostate cancer, melanoma, cancer in children and adolescents, cancer in hispanics, time trends in TNM staging, as well as NCDB data quality and hospital participation.

CONCLUSIONS

A multipurpose partnership between the NCDB and the Cancer Liaison Physician Network of the Commission on Cancer will be formed at the state and local level to promote NCDB participation as well as to disseminate the NCDB clinical findings. Additional sites will be covered in Annual Reviews, and highlights of those reports will be provided to Liaison Physicians of the Commission who are actively involved in the care of cancer patients to inform them of the latest findings.

The impact of intraoperative ultrasonography on surgery for liver neoplasms

To analyze the effect of IOUS on surgical decision making, we performed a retrospective study of 45 patients who had exploratory laparotomy and IOUS for liver neoplasms. Preoperative lesion detection was compared with intraoperative findings. The effect of IOUS on the choice of surgical procedure was analyzed. Preoperative imaging detected 67% of lesions, 78% when combined with surgical inspection and palpation, and 97% were recognized by IOUS. Surgery was modified in 23 of 45 cases (51%); 19 of those 23 cases (83%) were based on IOUS findings alone. IOUS demonstrated superior lesion detection over noninvasive preoperative liver imaging, and IOUS significantly affected surgical decision making.

Role of staging laparoscopy in the treatment of hepatic malignancy

Despite current radiologic imaging capabilities, 40% to 70% of patients with primary or metastatic hepatic malignancies are found to have unresectable disease at the time of laparotomy. The present study evaluates the use of laparoscopy in the staging of hepatic malignancy. Twenty-nine patients underwent staging laparoscopy prior to a planned laparotomy for resection of a hepatic malignancy that was deemed resectable by computed axial tomographic scan and ultrasonography. Twelve patients had primary hepatic malignancies, and 17 had metastatic malignancies. Laparoscopy demonstrated evidence of unresectability in 48% (14 of 29) of patients studied. Four patients had unsuspected cirrhosis, and 10 had unresectable or extrahepatic metastatic disease. Patients who underwent laparoscopy alone had shorter mean hospital lengths of stay than historical controls who underwent laparotomy alone. We conclude that diagnostic laparoscopy should precede laparotomy for planned resection of hepatic malignancies.

Localization of tumor-associated glycoprotein DF3 in normal, inflammatory, and neoplastic lesions of the colon

BACKGROUND

The expression of DF3 was assessed by a monoclonal antibody in normal, inflammatory, and neoplastic conditions in the large bowel.

METHODS

Using immunohistochemistry, expression was examined in formalin-fixed paraffin-embedded biopsy and resection samples of 19 normal colonic mucosal specimens, 49 inflammatory lesions, 34 adenomas, and 38 primary colonic adenocarcinomas. In addition, Western blots of normal colonic mucosa and adenocarcinoma were examined.

RESULTS

DF3 expression was detected in 84% of the adenocarcinomas with coarse membrane staining, intense positivity of luminal secretions, and focal cytoplasmic and intracytoplasmic vacuole staining. Nine of 32 areas of transitional mucosa revealed reactivity along apical membranes in crypt cells. Five adenomas containing carcinoma revealed DF3 positivity in the malignant areas only, whereas the remaining 29 were negative. Staining was membrane, luminal, and intracytoplasmic. Two examples of active ulcerative colitis revealed focal reactivity along the apical membrane of crypt cells. No other areas of staining were noted, including 12 cases containing dysplasia. Four of 10 other inflammatory lesions also revealed similar membrane reactivity in crypt cells. Normal colonic mucosa was nonreactive. Examples of normal colonic mucosa were negative for DF3 by Western blot analysis, whereas two carcinoma samples that reacted immunohistochemically were positive.

CONCLUSIONS

DF3 is not detectable in normal colonic tissues. It is expressed focally and predominantly along the apical membrane of crypt cells in some inflammatory lesions and in the transitional mucosa of primary adenocarcinomas. Most adenocarcinomas of the colon and adenomas with foci of invasive carcinoma demonstrate reactivity in the cytoplasm and luminal secretions.

Preoperative and postoperative combination chemotherapy for potentially resectable gastric carcinoma

BACKGROUND

Median survival of patients with local-regional gastric carcinoma is 10 months. Resection of the primary tumor and regional lymph nodes, with tumor-free margins (curative resection), has been the most effective treatment for local-regional gastric carcinoma. However, median survival of patients with curative resection of gastric carcinoma is 24 months, and the 5-year survival rate is about 20%. A single institution pilot study has established the feasibility of administering two courses of chemotherapy preoperatively and three courses postoperatively. In another study, a 15% pathologically documented complete response (pathologic complete response) has been reported in unresectable gastric carcinoma treated with etoposide, doxorubicin, and cisplatin.

PURPOSE

Our purpose was to increase the curative resection rate in potentially resectable gastric carcinoma and to delay or eliminate micrometastases and thus improve survival. We also evaluated clinical and pathologic response to chemotherapy.

METHODS

Forty-eight previously untreated patients with potentially resectable gastric carcinoma received a chemotherapy regimen (EAP) consisting of etoposide (120 mg/m2 intravenously over a 2-hour period on days 4, 5, and 6), doxorubicin (20 mg/m2 as a 10-minute intravenous infusion on days 1 and 7), and cisplatin (40 mg/m2 as a 1-hour intravenous infusion on days 2 and 8). Patients received three courses of chemotherapy before resection, and responding patients received two courses postoperatively. Clinical and pathologic response rates, toxicity, patterns of treatment failure, and survival times were assessed.

RESULTS

A median of three courses (range, 1-5) of preoperative therapy was administered; six (12%) of the 48 patients had clinical complete response, and nine (19%) had partial response. Forty-one (85%) underwent surgery; 37 (90%) of these 41 (77% of the 48 patients) had a curative resection. There were no pathologic complete responses. Median survival for all patients is 15.5 months (range, 2-29+ months). Therapy was discontinued because of the toxic effects in one patient before surgery and in six patients after surgery. Doses were reduced in 37 patients (77%), mainly because of hematologic toxicity. Nineteen (40%) were hospitalized because of toxic effects, including 15 patients who developed fever with neutropenia. Grade 3 or 4 nausea and vomiting occurred in 15 patients and grade 3 or 4 diarrhea in seven patients. One death was directly related to chemotherapy.

CONCLUSIONS

These data support that administration of preoperative and postoperative chemotherapy for local-regional gastric carcinoma is feasible in a multi-institutional setting. Our findings demonstrate that this EAP regimen is modestly active but is associated with substantial toxicity.

IMPLICATIONS

Use of preoperative chemotherapy in resectable gastric carcinoma merits further evaluation, but more effective drug regimens will be required before a controlled trial is initiated.

Nucleotide and deduced amino acid sequence of human ribosomal protein L18

Ribosomal protein L18 mRNA is overexpressed in human colorectal cancer compared to normal colon tissue. We report the nucleotide sequence of human L18 cDNA derived from a normal colon source. There were no mutational changes in segments of L18 cDNA derived from two tumor sources. The L18 cDNA was 690 base pairs long and predicts a single open reading frame of 564 nucleotides, encoding 188 amino acids with a M(r) = 21,621, it is homologous to rat L18 and Xenopus laevis L14.

Prothymosin-alpha mRNA expression correlates with that of c-myc in human colon cancer

Prothymosin alpha (PT-alpha) is a nuclear protein involved in cell proliferation. Transcription of PT-alpha has been reported to be regulated by the c-myc gene in vitro. We identified PT-alpha as being overexpressed in a human colon cancer minus normal mucosa subtraction cDNA library. Northern blot (messenger RNA) analysis showed that both PT-alpha and c-myc genes were overexpressed in human colorectal cancers compared with adjacent normal tissues. Immunohistochemical studies for PT-alpha and c-myc supported these findings. There was no correlation between PT-alpha or c-myc messenger RNA expression and Dukes' stage of colorectal cancer; or between either of these two and actin messenger RNA expression. There was, however, a significant correlation between the PT-alpha expression and c-myc expression (P < 0.001). These findings support the hypothesis that PT-alpha gene transcription may be associated with, and possibly under the control of, the c-myc gene in human colorectal cancers.

Gastric and hepatocellular carcinomas do not overexpress the same ribosomal protein messenger RNAs as colonic carcinoma

The levels of a number of ribosomal protein mRNAs are reported to be increased in human colon cancer. We have assessed whether selected ribosomal protein mRNAs are overexpressed in other gastrointestinal malignancies, namely gastric and hepatocellular carcinomas. Subtracted complementary DNA libraries were generated from paired samples of human (a) colorectal carcinoma minus adjacent normal colonic mucosa and (b) hepatocellular carcinoma minus adjacent normal liver. Screening of approximately 3% of these library clones determined that ribosomal protein mRNAs encoding L18 and L37 (not previously reported) and P0 and S6 were overexpressed in one or the other library. Their complementary DNA inserts were then used as probes to evaluate their expression in a larger number of paired tumor/normal surgical samples of human colonic, gastric, and hepatocellular carcinomas, by Northern hybridization. The mRNA signal was greater in the colonic carcinoma than in paired adjacent normal colonic mucosa in 38 of 42 cases for P0 [tumor/normal (T/N) ratio = 3.0 +/- 0.3, mean +/- SE, P < 0.001] (G. F. Barnard, R. J. Staniunas, S. Bao, K. Mafune, J. L. Gollan, G. D. Steele, Jr., and L. B. Chen, Cancer Res., 52: 3067-3072, 1992), in 25 of 28 cases for L18 (T/N ratio = 3.7 +/- 0.5, P < 0.001), in 27 of 28 cases for L37 (T/N ratio = 5.3 +/- 0.4, P < 0.001), and in 24 of 28 cases for S6 (T/N ratio = 3.1 +/- 0.5, P < 0.01). The level of mRNA overexpression of L18 and S6 did not correlate with the Dukes' stage of disease. In hepatocellular carcinoma samples, using the same four ribosomal protein complementary DNA probes, only P0 mRNA was significantly increased (T/N ratio = 2.8 +/- 0.4, n = 6, P = 0.047). In gastric carcinoma samples, none of these mRNAs was increased (mean T/N ratios = 0.9-1.2, n = 6). Therefore, gastric and hepatocellular carcinomas do not overexpress the same ribosomal protein mRNAs as do colonic carcinoma.

The significance of carbonic anhydrase expression in human colorectal cancer

BACKGROUND

Carbonic anhydrase isoenzymes I and II are present in normal colorectal mucosa. This study aimed to determine if carbonic anhydrase is present in colorectal cancer and what is its potential clinical significance.

METHODS

The messenger RNA (mRNA) and protein expression of carbonic anhydrase isoenzyme I were analyzed in fresh specimens of colorectal adenocarcinoma by Northern and Western blots, respectively. The immunohistochemical expression was subsequently studied in a larger number of formalin-fixed surgical specimens.

RESULTS

All of 30 normal colon samples had a strong RNA hybridization signal. Only 4 of 39 paired colorectal cancer and none of 9 normal liver samples had detectable levels of carbonic anhydrase mRNA. Isoenzyme I protein expression showed similar results. In a separate group of patients, immunohistochemical studies showed that 16 of 96 colorectal tumors had positive staining cells. All positive tumors were well or moderately differentiated carcinomas (P < 0.05). When analyzed retrospectively, immunoreactive cases were more likely to be in a group with a good outcome (P < 0.01) and to lack vascular invasion (P < 0.01) than negative cases.

CONCLUSIONS

The majority of colorectal cancers do not express carbonic anhydrase isoenzyme I. The presence of any isoenzyme I-positive immunoreactive cancer cells may be associated with a more favorable outcome in colorectal cancer.

The prognostic significance of proliferating cell nuclear antigen in clinical gastric cancer

BACKGROUND

Proliferating cell nuclear antigen (PCNA) is an intranuclear protein that is closely linked to the cell cycle. This antigen can be detected in formalin-fixed specimens. We studied the expression of PCNA in primary gastric cancer to identify its significance as a prognostic factor.

METHODS

The avidin-biotin-peroxidase complex method was used for PCNA staining in sections from 138 patients with primary gastric cancer. All sections were formalin fixed and paraffin embedded. Two different sections were examined in each case.

RESULTS

The PCNA labeling index (PCNA-positive cells/1000 cells x 100) varied from 7.0% to 59.7%. There were significant differences in tumor size, morphologic type, depth of tumor invasion, lymphatic permeation, vascular permeation, and lymph node metastasis between the high (> or = 33.4) and low (< 33.4) PCNA labeling index groups. The 5-year survival rates of the high and low PCNA labeling index groups were 5.8% and 66.2%, respectively, a significant difference (p < 0.001). Multivariate analysis showed that the PCNA labeling index was an independent prognostic factor for gastric cancer.

CONCLUSIONS

Because PCNA immunostaining can be done in routine formalin-fixed paraffin-embedded sections, this could be a powerful tool for providing information about the prognosis of patients with gastric cancer.

Modulation of mdr-1 expression by a H-ras oncogene in a human colon carcinoma cell line

In an established colon differentiation model, introduction of a c-H-ras-1 oncogene into a poorly differentiated human colon carcinoma cell line (Clone A) results in changes associated with the acquisition of a more differentiated phenotype. Down-regulation of mdr-1 mRNA was shown to accompany ras-related differentiation events resulting in decreased Pgp synthesis and a significant reduction in membrane Pgp as detected by immunoprecipitation, Western-blot and FACS analysis. Consistent with these observations was a reduction in Pgp-mediated drug resistance associated with Clone-A ras transfectants, with no alteration in drug sensitivity being observed with non-MDR drugs in these cells. An alternative differentiation model involves exposure of Clone-A cells to sodium butyrate. Under these conditions, differentiation-related changes resulted in up-regulation of mdr-1 mRNA and Pgp synthesis, although no alteration in drug sensitivity was recorded. In agreement with this observation, the levels of membrane-associated Pgp remained unchanged throughout the period of exposure to sodium butyrate. This study shows that modulation of Pgp expression in colon differentiation is dependent upon the differentiation induction agent used.

Decreased expression of Mac-2 (carbohydrate binding protein 35) and loss of its nuclear localization are associated with the neoplastic progression of colon carcinoma

The Mac-2 lectin (carbohydrate binding protein 35) is a soluble, 32- to 35-kDa phosphoprotein that binds galactose-containing glycoconjugates. We report here that the colonic epithelium is a major site of Mac-2 expression in vivo based on immunohistochemistry of human tissue specimens. In this epithelium, proliferating cells at the base of the crypts do not express Mac-2 but its expression increases with differentiation along the crypt-to-surface axis. Mac-2 expression is concentrated in the nuclei of these differentiated epithelial cells. The progression from normal mucosa to adenoma to carcinoma is associated with significant changes in Mac-2 nuclear localization and expression. In all adenomas (9/9) and carcinomas (13/13) examined, Mac-2 was not present in the nucleus but was localized in the cytoplasm. Sequencing of Mac-2 cDNAs from normal mucosa and carcinoma revealed no specific mutations that could account for this loss of nuclear localization. We also observed a 5- to 10-fold decrease in Mac-2 mRNA levels in cancer compared to normal mucosa as well as a significant reduction in the amount of Mac-2 protein expressed. These observations suggest that Mac-2 exclusion from the nucleus and its decreased expression may be related to the neoplastic progression of colon cancer.

Ubiquitin-ribosomal protein S27a gene overexpressed in human colorectal carcinoma is an early growth response gene

One of the extension proteins on the carboxy terminus of ubiquitin was reported as the ribosomal protein S27a. We have cloned a gene which encodes this ubiquitin hybrid protein from a complementary DNA library of a human colon carcinoma cell line. Northern blot analysis of surgical specimens from colon cancer patients showed that these messenger RNA levels were higher in tumor tissue than in adjacent normal mucosa. Furthermore, to investigate the role of this novel ubiquitin hybrid gene in cellular growth control, the responsiveness of this gene to serum growth factors was examined. Within 30 min after serum or 12-O-tetradecanoylphorbol-13-acetate stimulation, its messenger RNA expression in rat fibroblast cells (Rat 1) was increased. Nuclear runoff transcription studies showed that the kinetics of induction of this gene is almost identical to that of protooncogene c-jun or c-fos, the known early growth response genes. Thus, this ubiquitin hybrid gene appears to be a novel early growth response gene overexpressed in human colon cancer and warrants further studies in the pathogenesis of colorectal carcinoma.

Human and murine Kupffer cell function may be altered by both intrahepatic and intrasplenic tumor deposits

The liver is the most common site of hematogenous metastases from colorectal carcinoma. Kupffer cells (KC), which line the hepatic sinusoids, may form the first line of defense against circulating tumor cells. The purpose of this study was to determine the effect of hepatic metastases and intra-abdominal tumor growth on KC binding of human colorectal carcinoma (HCRC) cells. MIP-101, a poorly metastatic cell line, and CX-1, a highly metastatic cell line, were injected intrasplenically into nude mice and KC were isolated by collagenase perfusion at varying intervals after injection. Conditioned media were collected from MIP-101, CCL 188 and CX-1 to determine their in vitro effect on KC function. KC from MIP-101 injected mice (14% liver metastases, 100% splenic tumors) bound a significantly greater number of MIP-101 and clone A cells than CX-1 cells in vitro. KC isolated from mice 5 weeks after CX-1 injection (100% liver metastases) also showed increased binding of MIP-101 and clone A cells compared to CX-1 cells. Similar results were obtained when tumor cell binding to normal human liver KC was compared to binding to KC from human livers from patients with hepatic metastasis from colorectal cancer. In contrast KC obtained from mice 3 weeks after CX-1 injection (44% liver metastases) showed significantly decreased binding of MIP-101 and clone A cells. The conditioned medium from CX-1 cells significantly decreased the in vitro binding of both MIP-101 and CX-1 by KC. These results indicate that the ability of KC to bind HCRC cells (which precedes phagocytosis and tumor cell killing) is a dynamic function and affected by concomitant tumor growth. HCRC cells may alter KC function via the production of specific tumor-derived soluble factors. In order to devise new and more effective therapeutic options in the treatment of liver metastases the nature of this tumor cell-KC interaction must be better understood.

[Cellular and molecular biological study of the laminin-binding protein and its clinical application]

Tumor invasion and metastasis involve the interaction between tumor cells and basement membrane, which is mediated in part by laminin receptors. To search for tumor-associated-genes which can be used as new markers in colon cancers with known poor prognosis, cDNA libraries from a colon cancer cell line and colonic tissues were constructed and screened. We selected a cDNA clone which encodes 32-kD laminin-binding protein (LBP-32), and showed increased mRNA expression of LBP-32 in colon carcinoma. This mRNA expression was also correlated with clinical tumor staging. Furthermore, to investigate the role of LBP-32 in cancer invasion and metastasis, cell adhesion assays and in vitro invasion assays were performed, using anti-sense RNA of LBP-32 to block the synthesis of LBP-32. Results showed that anti-sense RNA of LBP-32 inhibits tumor cell attachment and invasiveness in vitro in transfectants of a colon cancer cell line. These data suggest that LBP-32 may play an important role in colon cancer progression, and that LBP-32 may be used as a marker of biological aggressiveness. These findings also imply that laminin receptors may provide a target for novel therapeutic strategies: modulating LBP-32 expression by anti-sense RNA or monoclonal antibodies may have clinical application in colorectal cancer therapy.

Sucrase-isomaltase expression in chronic ulcerative colitis and dysplasia

Sucrase-isomaltase (SI) is a mucosal disaccharidase that is present in normal small intestine and fetal colon. It also has been noted in colonic adenomas and adenocarcinomas. We used a polyclonal antibody to human SI to investigate enzyme presence and utility in detecting dysplastic changes in chronic ulcerative colitis. Sections from 32 cases were reviewed for the presence or absence of active colitis and dysplasia. Immunostaining of these cases for SI was performed and the results were reported based on location of immunoreactivity (ie, membrane and cytoplasmic staining in superficial and crypt epithelial cells) and percentage of positivity. Of 81 sections examined, 48 were rated negative for dysplasia (23 inactive colitis, 20 active, and five probably negative) and 28 were rated positive (eight low grade and 20 high grade). Surface membrane staining of epithelial cells was noted in all 28 dysplastic slides and positive cases (sensitivity, 100%) but also in 29 of 48 negative sections (P less than .001). In contrast, cytoplasmic positivity was present in 25 of 28 dysplastic and in only two of 48 negative slides (P less than .0001). The presence of cytoplasmic staining of SI in the superficial or crypt cells revealed a sensitivity of 92% and a specificity of 94%. There were five additional sections rated as indefinite for dysplasia (probably positive or unknown); two showed staining patterns typical of negative slides and three showed positive staining patterns. Of the 18 samples of transitional mucosa next to areas of dysplasia, surface membrane staining of SI was seen in all samples and cytoplasmic staining was seen in 15. We conclude that membrane staining of SI can be detected in inflammatory, regenerative, and dysplastic mucosa in ulcerative colitis. Cytoplasmic staining, however, correlates strongly with the presence of dysplastic change and may help in its detection.

Increased expression of human ribosomal phosphoprotein P0 messenger RNA in hepatocellular carcinoma and colon carcinoma

To search for differentially expressed gene products in selected cancers of endodermal origin, cDNA libraries derived from mRNA in human hepatocellular carcinoma and adjacent grossly normal tissue were generated. From these parent libraries, subtracted cDNA libraries of tumor minus normal and normal minus tumor tissues were constructed. After screening these subtracted libraries by +/- hybridization, a cDNA clone that is overexpressed in hepatocellular carcinoma and encodes the human acidic ribosomal phosphoprotein P0 (P0) was identified. We then evaluated the expression of this phosphoprotein P0 in human colon carcinoma samples. Surgical specimens of primary tumors and liver metastases were examined by Northern hybridization of total RNA with one of 2 32P-labeled P0 probes. The mRNA level of the P0 was greater in primary colon carcinoma than in paired adjacent normal colonic epithelium in 36 of 38 cases; the mean tumor/normal ratio was 2.7 (range, up to 13). The tumor/normal ratio, when plotted against the Dukes' stage of disease, gave evidence for increasing P0 expression with increasing stage of colon carcinoma (P = 0.02). In all 8 cases of paired colon carcinoma metastatic to liver and 2 cases of paired primary hepatocellular carcinoma, the P0 mRNA level was greater in tumor than in adjacent normal liver tissue. The mean tumor/normal ratio was 4.0 (range, up to 11) for the colon cancers metastatic to liver and 4.2 for the primary hepatocellular carcinoma samples. These findings support a common increased expression of selected gene products in different tumors of endodermal origin and suggest that increased P0 expression, in line with certain other ribosomal proteins, may be associated with human colorectal cancer progression and biological aggressiveness.

Technical and biological factors in disease-free survival after hepatic resection for colorectal cancer metastases

Careful patient selection for hepatic resection of colorectal cancer metastases is essential to improve current poor results. Carcinoembryonic antigen level and number of metastases were significant preoperative prognostic indicators of 5-year disease-free survival in patients selected clinically for hepatic surgery. Surgical margin, weight of hepatic tissue resected, carcinoembryonic antigen level, and flow cytometry were significant postoperative prognostic indicators. Patients with a carcinoembryonic antigen level less than 200 ng/mL, 1-cm surgical margins, and less than 1,000 g of liver tissue removed had a greater than 50% estimated 5-year disease-free survival rate. If the metastases were diploid on flow cytometry, an additional survival advantage may have been gained. Inadequate surgical margins led to high rates of liver-only recurrence. Nonhepatic recurrence was unrelated to surgical margins. Intraoperative liver examination by ultrasound during primary colon cancer resection and adjuvant chemotherapy may offer earlier selection of biologically appropriate patients and improved outcome; both recommendations require clinical trials.

The integrin alpha 6 beta 4 is a laminin receptor

In this study, the putative laminin receptor function of the alpha 6 beta 4 integrin was assessed. For this purpose, we used a human cell line, referred to as clone A, that was derived from a highly invasive, colon adenocarcinoma. This cell line, which expresses the alpha 6 beta 4 integrin, adheres to the E8 and not to the P1 fragment of laminin. The adhesion of clone A cells to laminin is extremely rapid with half-maximal adhesion observed at 5 min after plating. Adhesion to laminin is blocked by GoH3, and alpha 6 specific antibody (60% inhibition), as well as by A9, a beta 4 specific antibody (30% inhibition). Most importantly, we demonstrate that alpha 6 beta 4 binds specifically to laminin-Sepharose columns in the presence of either Mg2+ or Mn2+ and it is eluted from these columns with EDTA but not with NaCl. The alpha 6 beta 4 integrin does not bind to collagen-Sepharose, but the alpha 2 beta 1 integrin does bind. Clone A cells do not express alpha 6 beta 1 as evidenced by the following observations: (a) no beta 1 integrin is detected in beta 1 immunoblots of GoH3 immunoprecipitates; and (b) no alpha 6 beta 1 integrin is seen in GoH3 immunoprecipitates of clone A extracts that had been immunodepleted of all beta 4 containing integrin using the A9 antibody. These data establish that laminin is a ligand for the alpha 6 beta 4 integrin and that this integrin can function as a laminin receptor independently of alpha 6 beta 1.

Etoposide, doxorubicin, and cisplatin chemotherapy for advanced gastric adenocarcinoma: results of a phase II trial

PURPOSE

A phase II study of etoposide, doxorubicin, and cisplatin (EAP) therapy in patients with advanced gastric carcinoma was performed in an attempt to confirm encouraging results reported by German investigators using an identical EAP regimen.

PATIENTS AND METHODS

Thirty-six consecutive, previously untreated patients with surgically unresectable, measurable gastric carcinoma were treated every 28 days with etoposide (120 mg/m2, days 4, 5, and 6), doxorubicin (20 mg/m2, days 1 and 7), and cisplatin (40 mg/m2, days 2 and 8). A total of 108 courses of treatment was given.

RESULTS

Therapy was associated with myelosuppression (median granulocyte nadir, 239/microL; median platelet nadir, 81,000/microL), which reached its maximum 14 days after the start of therapy and necessitated hospitalization after 24 of 108 (22%) treatment courses. Four of 36 (11%) patients died of treatment-related toxicity: three from sepsis and one from hemorrhage. Objective responses were observed in 12 of 36 (33%) patients; three (8%) patients experienced a clinical complete response. The median time to progression was 4 months for all 36 patients and 8 months for the 12 responding patients. Of the 13 patients with localized but unresectable disease, five subsequently underwent surgical resection; only one of these five was rendered disease-free.

CONCLUSION

The EAP regimen is highly toxic and results in response rates and survival times no better than those of more easily tolerated treatment programs.

Sialyltransferase activity and hepatic tumor growth in a nude mouse model of colorectal cancer metastases

Sialyltransferase activity (EC 2.4.99.6) was measured in the microsomal fraction of colorectal cancer cell lines using an assay based on the incorporation of [14C]CMP-sialic acid into asialofetuin. In the poorly differentiated lines MIP101 and Clone A, sialyltransferase activity had a Vmax of 0.36 and 0.31 nmol/mg protein/h, respectively, while the moderately differentiated to well-differentiated cell lines HT-29, CCL188, and CX-1 had Vmaxs of 2.46, 1.05, and 1.24 nmol/mg protein/h, respectively. All cell lines tested had a Km of 15.4 (+/- 0.7)(SD) mumol/liter. The better differentiated cells had higher levels of sialyltransferase activity, which correlated with their higher levels of sialic acid and their enhanced ability to form liver metastases in the nude mouse following intrasplenic injection compared to the poorly differentiated cell lines. Treatment of the cell lines with KI-8110, a CMP-sialic acid derivative which prevents incorporation of sialic acid into glycoconjugates, resulted in reduced formation of hepatic metastases by the colorectal carcinoma cell lines in the nude mouse model. It is suggested that reduced sialylation of adhesion molecules such as carcinoembryonic antigen may change the biology of the tumor cell, one consequence of which is the prevention of implantation of the cells into distant sites, resulting in a reduced incidence of metastases.

[Experimental liver metastases of human colonic cancer: correlation with degree of differentiation and CEA production]

The influence of cellular differentiation and CEA-production by colorectal tumor cells on experimental hepatic metastases was studied. Eight human colon cancer cell lines were injected into the spleen of athymic mice. The four poorly differentiated, non or low CEA producing cell lines were poorly metastatic to the liver. In contrast, the four well-differentiated cell lines which produce moderate to high levels of CEA were highly metastatic. We conclude in this animal model that poorly differentiated, non or low CEA producing colorectal cell lines have a lower metastatic potential compared to the well-differentiated, high CEA producing tumor cells.

Differences in messenger RNA expression of carcinoembryonic antigen in surgical specimens of colorectal carcinoma

Carcinoembryonic antigen (CEA) is the most widely used tumor marker for colorectal cancer. Plasma CEA levels have been variably associated with prognosis. Since plasma CEA level is multifactorial, CEA gene expression in tumors may provide one precise mechanism to evaluate its functional role. This study evaluated CEA expression at the messenger RNA (mRNA) level in 22 human colorectal carcinomas and their adjacent normal mucosae by Northern blot hybridization using a 32P-labeled CEA probe (a loop-domain specific cDNA, LV7). Both tumor and normal mucosa displayed three mRNA species of 4.0, 3.6, and 3.0 kb in length. The expression of 3.6-kb mRNA which encodes for CEA was dominant and it was correlated with another 4.0-kb CEA mRNA expression. The expression of 3.0-kb mRNA which encodes for nonspecific cross-reacting antigen was weak and not detectable in 8 of 22 colon tumors and 12 of 22 normal colon mucosae. In only one tumor, a 4.5-kb mRNA (which might encode for a new family member of CEA) was expressed. A two- to fourfold higher expression of CEA mRNA (3.6 kb) was observed in 11 of 22 colorectal tumors (2 of 9 proximal colon tumors and 9 of 14 rectosigmoid tumors) when compared with morphologically normal adjacent mucosae. Preoperative plasma CEA levels and Dukes' staging had no correlation with this CEA mRNA expression. CEA mRNA did not appear to correlate with metastasis because its expression in the primary colon cancers with metastases (Dukes' stage D tumor) was not always increased. These data also imply that factors other than mRNA expression in tumor might be important in regulating plasma CEA levels.

Regional differences in surgical management of breast cancer

Data voluntarily submitted to the NCDB by 597 hospitals throughout the US indicate marked variations in the type of surgery used for the treatment of breast cancer. Patients in New England with early stage breast cancer are much more likely to be treated with partial mastectomy than are patients in the East South Central or West North Central regions.

Metastatic potential of human colon cancer cell lines: relationship to cellular differentiation and carcinoembryonic antigen production

The relationship between cellular differentiation and carcinoembryonic antigen (CEA) production by human colorectal tumor cells and their ability to form hepatic metastases was studied. Eight human colon cancer cell lines were injected into athymic mice using different routes of administration to characterize their metastatic potential. The four poorly differentiated, non or low CEA producing cell lines were poorly metastatic to the liver after intrasplenic injection. After intraperitoneal implantation the same cell lines were highly tumorigenic, and subsequently metastatic to the liver. In contrast, the four moderate to well-differentiated cell lines that produced moderate to high levels of CEA were highly metastatic to the liver following intrasplenic injection. After intraperitoneal implantation they were less tumorigenic, and metastatic to the liver. We conclude that in this system poorly differentiated non or low CEA producing colorectal cell lines have a lower metastatic capacity compared to the well-differentiated high CEA producing colorectal cell lines. These data correlate directly with the pattern of metastatic spread and clinical course observed in patients with these tumors, suggesting that degree of differentiation and level of CEA production may play a role in development of site-specific metastases.