Disappearance Curves of Tumor Markers after Radical Surgery

A new staging system for postoperative prognostication in pancreatic ductal adenocarcinoma

The current TNM staging system for pancreatic ductal adenocarcinoma (PDAC) has revised the definitions of T and N categories as well as stage groups. However, studies validating these modifications have yielded inconsistent results. The existing TNM staging system in prognostic prediction remains unsatisfactory. The prognosis of PDAC is closely associated with pathological and biological factors. Herein, we propose a new staging system incorporating distant metastasis, postoperative serum levels of CA19-9 and CEA, tumor size, lymph node metastasis, lymphovascular involvement, and perineural invasion to enhance the accuracy of prognosis assessment. The proposed staging system exhibited a strong correlation with both overall survival and recurrence-free survival, effectively stratifying survival into five distinct tiers. Additionally, it had favorable discrimination and calibration. Thus, the proposed staging system demonstrates superior prognostic performance compared to the TNM staging system, and can serve as a valuable complementary tool to address the limitations of TNM staging in prognostication.

Importance of Normalization of Carbohydrate Antigen 19-9 in Patients With Intrahepatic Cholangiocarcinoma

Background

Although carbohydrate antigen 19-9 (CA19-9) is an established prognostic marker for intrahepatic cholangiocarcinoma (ICC) patients, the significance of elevated preoperative CA19-9 that normalized after resection remains unknown. This study aimed to investigate whether elevated preoperative CA19-9 that normalized after curative resection had an impact on prognosis among patients with ICC.

Methods

Patients who underwent curative resection for stage I to III ICC between 2009 and 2018 were identified. Patients were categorized into three cohorts: normal preoperative CA19-9, elevated preoperative CA19-9 but normalized postoperative CA19-9, and persistently elevated postoperative CA19-9. Overall survival (OS), recurrence-free survival (RFS), and hazard function curves over time were analyzed.

Results

A total of 511 patients (247 [48.3%] male; median age, 58 years) were included. Patients with elevated preoperative CA19-9 (n = 378) were associated with worse RFS and OS than those with normal preoperative CA19-9 (n = 152) (both p < 0.001). Patients with persistently elevated postoperative CA19-9 (n = 254) were correlated with lower RFS and OS than the combined cohorts with normal postoperative CA19-9 (n = 257) (both p < 0.001). The hazard function curves revealed that the risk of recurrence and mortality peaked earlier and higher in the elevated postoperative CA19-9 group than the other 2 groups. Multivariate analyses identified persistently elevated, rather than normalized, postoperative CA19-9 as an independent risk factor for shorter RFS and OS in ICC.

Conclusions

Elevated preoperative serum CA19-9 that normalizes after curative resection is not an indicator of poor prognosis in ICC. Patients with persistently elevated postoperative CA19-9 are at increased risk of recurrence and death.

A case of raised CA 19-9 in a patient with desmoplastic fibroblastoma of the upper limb

Carbohydrate antigen 19-9 (CA 19-9) is a tumor marker widely accepted as the most useful blood test in diagnosing and monitoring pancreatic cancer. However, CA 19-9 may also be raised in other conditions such as colorectal, hepatic, lung, and ovarian carcinoma as well as benign conditions such as hepatobiliary and pulmonary diseases. CA 19-9 is rarely elevated above 200 U/ml in benign conditions with values exceeding 1000 U/ml being highly suggestive of malignancy. The mechanism of secretion in both malignant and benign conditions remains unclear. Desmoplastic fibroblastoma (DF) is a benign soft tissue tumor. CA 19-9 has not been reported in association with DF previously. We present a case of raised serum CA 19-9 in a 71-year-old male attributed solely to DF in his left cubital fossa. The patient's CA 19-9 level rose from 56 U/ml at the time of presentation to 3763.8 U/ml over a period of 9 months. Post-DF excision, the CA 19-9 level decreased to 1464 U/ml at 1 month, 162.3 U/ml at 2.5 months, and 24U/ml, within normal range, at 7 months post-surgery. CA 19-9 levels continued to remain at 24 U/ml 1.5 years post-tumor excision. The CA 19-9 level in this patient was highly elevated which is unusual in association with a benign tumor. The rate of decrease in CA 19-9 level post-excision was in keeping with that reported after pancreatic cancer resections. This is the first case of DF in association with raised CA 19-9.

Circulating tumour DNA as a cancer biomarker

Measurement of genetically altered DNA shed from tumours into the circulation can potentially provide a new generation of blood-based cancer biomarkers. Compared with tissue DNA biomarkers which require surgery or biopsy, samples for circulating tumour DNA assays can be obtained with minimal inconvenience and at lower cost. Furthermore, in contrast to tissue, the use of circulating tumour DNA allows serial monitoring, faster delivery of results and potentially provides an integrative representation of genetic alterations across all tumour sites within a patient. In contrast to existing protein-based cancer biomarkers, all of which can be produced by benign disease, circulating tumour DNA biomarkers would be expected to be more specific for malignancy. Furthermore, unlike the available blood cancer biomarkers, circulating tumour DNA can be used to predict response to specific therapies, identify mechanisms of therapy resistance and detect potentially actionable mutations. One of the first circulating tumour DNA assays recommended for clinical use involves EGFR mutation testing for predicting response to EGFR tyrosine kinase inhibitors in patients with advanced non-small cell lung cancer, especially when tumour tissue is unavailable. In order to accelerate the introduction of circulating tumour DNA assays into routine clinical use, laboratory medicine staff will have to undergo training in the use of polymerase chain reaction and DNA sequencing. Furthermore, existing circulating tumour DNA assays will need to be simplified, standardized, shown to have clinical utility, be made available at reasonable costs and be reimbursable.

Perioperative Serum Carcinoembryonic Antigen Ratio Is a Prognostic Indicator in Patients With Stage II Colorectal Cancer

Purpose

The aim of this study was to evaluate whether the perioperative carcinoembryonic antigen (CEA) ratio could be used as a determinant for adjuvant therapy after curative surgery in stage II colorectal cancer.

Methods

Data for 119 patients with stage II colorectal cancer who underwent radical surgery between 2010 and 2013 were collected. The perioperative CEA ratio was defined as the postoperative/preoperative serum CEA level, and the patients were grouped according to their perioperative CEA ratios: high ratio (≥0.5) and low ratio (<0.5). Overall survival rates were calculated, and their prognostic significances were analyzed.

Results

The overall survival rates of the high and the low perioperative CEA groups were 68.2% and 86.8%, respectively (P = 0.033). In patients with normal preoperative CEA levels (<5 ng/mL), the high perioperative CEA ratio group showed a worse survival rate than the low perioperative CEA ratio group (71.7% vs. 100.0%, P = 0.007). In patients with high preoperative CEA levels (≥5 ng/mL), the high perioperative CEA ratio group showed a worse survival rate than the low perioperative CEA ratio group (33.3% vs. 75.0%, P = 0.036). In the multivariate analysis, perioperative CEA ratio (P = 0.046), age (P = 0.034), and venous invasion (P = 0.015) were independent prognostic factors for survival.

Conclusion

The perioperative CEA ratio is a prognostic indicator for stage II colorectal cancer. Patients with normal preoperative serum CEA levels might also be considered for adjuvant therapy if their perioperative CEA ratios are higher than 0.5.

Postoperative serum CEA and CA125 levels are supplementary to perioperative CA19-9 levels in predicting operative outcomes of pancreatic ductal adenocarcinoma

BACKGROUND

Carbohydrate antigen (CA19-9) is a well-established marker to monitor disease status after resection of pancreatic cancer. However, few serum markers have been reported to improve the prognostic ability of postoperative CA19-9, especially in patients with normal postoperative CA19-9.

METHODS

A total of 353 patients with pancreatic ductal adenocarcinoma treated by radical resection were reviewed retrospectively, and a prospective cohort including 142 patients with resectable pancreatic head carcinoma was analyzed as a validation cohort. Perioperative CA19-9 and postoperative serum markers (CEA, CA242, CA72-4, CA50, CA125, CA153, and AFP) were investigated.

RESULTS

Patients with postoperative normalization of CA19-9 had improved survival times (recurrence-free survival: 11.9 months; overall survival: 22.5 months) compared with those with decreased but still elevated postoperative CA19-9 (recurrence-free survival: 6.8 months, P < .001; overall survival: 13.5 months, P < .001) or those with increased postoperative CA19-9 (recurrence-free survival: 3.5 months, P < .001; overall survival: 7.9 months, P < .001), which was similar to those with consistently normal CA19-9 during perioperative periods (recurrence-free survival: 10.6 months, P = .799; overall survival: 24.1 months, P = .756). Normal postoperative CA19-9 levels were an independent indicator for a positive outcome after operation, regardless of preoperative CA19-9 levels. Elevated postoperative CEA and CA125 were identified further as independent risk factors for patients with normal postoperative CA19-9, while elevated postoperative CA125 and nondecreased postoperative CA19-9 were independent prognostic markers for patients with elevated postoperative CA19-9.

CONCLUSION

The postoperative monitoring of CEA and CA125 provided prognostic significance to the measurement of CA19-9 in pancreatic cancer after resection.

Prognostic impact of carcinoembryonic antigen and carbohydrate antigen 19-9 in stage IV colorectal cancer patients after R0 resection

BACKGROUND

Although preoperative carcinoembryonic antigen (pre-CEA) and carbohydrate antigen 19-9 (pre-CA 19-9) are reportedly prognostic indicators for colorectal cancer (CRC), the prognostic roles of postoperative CEA (post-CEA) and CA 19-9 (post-CA 19-9) shortly after surgery have not been clarified in patients with curatively resected stage IV CRC. The aim of this study was to evaluate the predictive abilities of post-CEA and post-CA 19-9.

METHODS

A total of 129 consecutive patients who had stage IV CRC and underwent R0 resection were retrospectively analyzed. Pre-CEA and post-CEA and CA 19-9 levels were measured within 1 mo before and 3 mo after surgery, respectively. Relapse-free survival (RFS) and overall survival were estimated using the Kaplan-Meier method, and multivariate analysis was performed using the Cox proportional hazards model.

RESULTS

Pre-CEA was elevated (≥5.0 ng/mL) in 73.6% of the patients and remained elevated after surgery in 32.7% of the patients. Elevated post-CA 19-9 (≥50 U/mL) was observed in 9.5% of the patients. Neither elevated pre-CEA nor elevated pre-CA 19-9 was significantly associated with RFS but both elevated post-CEA and elevated post-CA 19-9 were associated with markedly reduced RFS (P = 0.0002 and P = 0.0004, respectively). When considered in combination, post-CEA and post-CA 19-9 significantly stratified RFS and was an independent predictive factor for recurrence (P = 0.0035), as was lymphatic invasion (P = 0.0015). Post-CA 19-9 was the only evident independent predictive factor for overall survival (P = 0.0336).

CONCLUSIONS

In patients with stage IV CRC who underwent curative resection, the combination of post-CEA and post-CA 19-9 at 3 mo after surgery was a potent prognostic indicator for recurrence.

Normalization of CA19-9 following resection for pancreatic ductal adenocarcinoma is not tantamount to being cured?

BACKGROUND

Postoperative carbohydrate antigen 19-9 (CA19-9) is an independent predictor of survival for pancreatic ductal adenocarcinoma (PDAC), and more powerful than preoperative CA19-9. However, making decisions just dependent on postoperative CA19-9 may result in necessary treatments not being performed.

MATERIALS AND METHODS

A total of 178 patients with resected PDAC were eligible for this retrospective study, classified into two corresponding subgroups according to postoperative CA19-9. Prognostic significance of all clinicopathologic factors was evaluated by univariate and multivariate analyses.

RESULTS

Postoperative CA19-9, preoperative CA125 and lymph node status were independent predictors. Better predictive performances for overall survival (OS) and recurrence-free survival (RFS) were achieved by postoperative CA19-9 compared to preoperative CA125 and lymph node status. Particularly, preoperative CA125 was associated with poor OS (p<0.001 for the normalized CA19-9 patients, p=0.012 for the elevated) and RFS (p=0.005 for the normalized, p=0.004 for the elevated). Moreover, preoperative CA125 levels related with survival in double- negative patients.

CONCLUSIONS

Normalization of CA19-9 is not tantamount to be cured. Preoperative CA125 is a critical predictor for PDAC patients, especially in double-negative patients.

A critical review of the analytical approaches for circulating tumor biomarker kinetics during treatment

Changes in serum tumor biomarkers may indicate treatment efficacy. Traditional tumor markers may soon be replaced by novel serum biomarkers, such as circulating tumor cells (CTCs) or circulating tumor nucleic acids. Given their promising predictive values, studies of their kinetics are warranted. Many methodologies meant to assess kinetics of traditional marker kinetics during anticancer treatment have been reported. Here, we review the methodologies, the advantages and the limitations of the analytical approaches reported in the literature. Strategies based on a single time point were first used (baseline value, normalization, nadir, threshold at a time t), followed by approaches based on two or more time points [half-life (HL), percentage decrease, time-to-events…]. Heterogeneities in methodologies and lack of consideration of inter- and intra-individual variability may account for the inconsistencies and the poor utility in routine. More recently, strategies based on a population kinetics approach and mathematical modeling have been reported. The identification of equations describing individual kinetic profiles of biomarkers may be an alternative strategy despite its complexity and higher number of necessary measurements. Validation studies are required. Efforts should be made to standardize biomarker kinetic analysis methodologies to ensure the optimized development of novel serum biomarkers and avoid the pitfalls of traditional markers.

Impact of the post/preoperative serum CEA ratio on the survival of patients with rectal cancer

PURPOSE

This study demonstrated the usefulness of the post/preoperative serum carcinoembryonic antigen (CEA) ratio as a predictor of survival after surgery for stage III rectal cancer patients.

METHODS

One hundred and four patients with stage III rectal cancer who underwent surgery between 1991 and 2000 were enrolled. The ratio of the postoperative serum CEA value divided by the preoperative serum CEA value was defined as post/preoperative serum CEA ratio, and the patients were separated into two groups: post/preoperative serum CEA ratio ≤ 1 (n = 86) and >1 (n = 18).

RESULTS

The multivariate analyses demonstrated that the intraoperative blood loss, lack of a sphincter-saving procedure and a post/preoperative serum CEA ratio >1 were independent factors predicting a poor prognosis for the overall and disease-free survival. The overall and disease-free survival rates among patients with a high preoperative serum CEA level (>5 ng/ml) or patients with a high postoperative serum CEA (>5 ng/ml) were longer in patients with a post/preoperative serum CEA ratio ≤ 1, in comparison to those with a post/preoperative serum CEA ratio >1. Liver metastasis was observed more frequently in patients with a post/preoperative serum CEA ratio >1.

CONCLUSIONS

The post/preoperative serum CEA ratio may be a predictor of the prognosis after surgery for stage III rectal cancer patients.

Detection of perioperative cancer antigen 72-4 in gastric juice pre- and post-distal gastrectomy and its significances

Gastric carcinoma is one of the most common malignancies nowadays, and caner antigen 72-4 (CA 72-4) in gastric juice has been rarely studied. To compare CA 72-4 in gastric juice pre- and post-distal gastrectomy (DG) and analyze its possible significances, we selected 64 patients diagnosed with gastric carcinoma who underwent DG and collected their perioperative gastric juice samples whose contents of CA 72-4 were detected. We found that CA 72-4 in gastric juice pre-gastrectomy is significantly higher among patients in advanced stages and correlated with tumor TNM classification (P < 0.01), within which tumor size, levels of gastric wall invaded, and number of metastatic lymph nodes are significant influencing factors (P < 0.05); CA 72-4 in gastric juice post-gastrectomy is significantly higher than that pre-surgery (P < 0.01), and it is significantly correlated with tumor TNM classification and radical degree (P < 0.01), and regards the sum of distances from tumor to two cutting edges and the classification of cutting edge as significant impact factors (P < 0.05); nine patients whose CA 72-4 in gastric juice rose post-DG show features indicating poor prognosis; the difference of CA 72-4 in gastric juice between pre- and post-gastrectomy is significantly correlated with tumor TNM classification and radical degree (P < 0.05), and regards tumor size, levels of gastric walls invaded, the sum of distances from tumor to two cutting edges and the classification of cutting edge as significant influential factors (P < 0.05). We conclude that CA 72-4 in gastric juice pre- and post-gastrectomy can provide us with much information about tumor and radical gastrectomy and that CA 72-4 in gastric juice post-gastrectomy and the difference of CA 72-4 in gastric juice between pre- and post-gastrectomy may indicate prognosis.

Study on the mechanism causing elevation of serum CA19-9 levels in diabetic patients

Serum CA19-9 levels are often elevated in diabetic patients. To elucidate this mechanism, we investigated the metabolism of CA19-9 in diabetic patients without obvious cancer. Study 1 included 119 patients in whom HbA1c, glycated albumin (GA) and CA19-9 were measured at the time of hospital admission. Study 2 examined 6 patients with markedly elevated CA19-9 levels (≥100 U/mL). Their half-lives for HbA1c, GA, and serum CA19-9 were calculated using the data before and after diabetes treatment. Three diabetic patients with pancreatic cancer were also examined as controls. In Study 1, serum CA19-9 (logarithmically transformed value) was significantly correlated with fasting plasma glucose (FPG), HbA1c and GA. On multivariate analysis, GA and FPG, but not HbA1c, were significant explanatory variables for serum CA19-9. In Study 2, serum CA19-9 decreased together with HbA1c and GA after diabetes treatment. The calculated half-lives for HbA1c, GA, and serum CA19-9 were 33.8 days, 16.1 days, and 10.9 days, respectively. The half-life of serum CA19-9 was longer in the study patients than that reported in patients with malignant tumors. By contrast, in the diabetic patients with pancreatic cancer serum CA19-9 showed a marginal decrease after diabetes treatment. Taken all together, prolonged half-life of serum CA19-9 may contribute to the increase in serum CA19-9 levels in diabetic patients without obvious cancer.

Prognostic impact of postoperative serum CA 19-9 levels in patients with resectable pancreatic cancer

BACKGROUND

Perioperative serum carbohydrate antigen 19-9 (CA 19-9) level has been reported to be a useful prognostic marker in pancreatic cancer. The object of this study was to investigate the predictive factors for survival, including preoperative and postoperative serum CA 19-9 levels in patients with pancreatic cancer.

METHODS

Between 2003 and 2009, a total of 269 patients with pancreatic invasive ductal carcinoma underwent macroscopically curative resection, and pre- and postoperative (within 3 months after surgery) serum CA 19-9 levels were evaluated in all of them. The prognostic significance of clinicopathologic factors was evaluated by univariate and multivariate analyses.

RESULTS

Preoperative serum CA 19-9 levels were higher than normal (>37 U/ml, 38-4600 U/ml) in 218 of 269 patients. Of these, after surgery, serum CA 19-9 level returned to within a normal range in 136 patients (62%), whereas 82 patients (38%) remained in the higher-than-normal range. In univariate and multivariate analyses, node metastasis (P < 0.001) and postoperative CA 19-9 level (>37 U/ml) (P < 0.0001) were independent predictors for poor survival. Postoperative CA 19-9 level was higher in patients with microscopically positive surgical margin (P = 0.02). Hepatic recurrence and peritoneal dissemination were associated with postoperative higher CA 19-9 level.

CONCLUSIONS

Postoperative CA 19-9 level was associated with positive surgical margin and hepatic or peritoneal recurrence and may be a useful predictor for survival in patients with pancreatic cancer.

Pretreatment carbohydrate antigen 19-9 level indicates tumor response, early distant metastasis, overall survival, and therapeutic selection in localized and unresectable pancreatic cancer

PURPOSE

The use of chemoradiotherapy (CRT) for localized and unresectable pancreatic cancer has been disputed because of high probability of distant metastasis. Thus, we analyzed the effect of clinical parameters on tumor response, early distant metastasis within 3 months (DM(3m)), and overall survival to identify an indicator for selecting patients who would benefit from CRT.

METHODS AND MATERIALS

This study retrospectively analyzed the data from 84 patients with localized and unresectable pancreatic cancer who underwent CRT between August 2002 and October 2009. Sex, age, tumor size, histological differentiation, N classification, pre- and post-treatment carbohydrate antigen (CA) 19-9 level, and CA 19-9 percent decrease were analyzed to identify risk factors associated with tumor response, DM(3m), and overall survival.

RESULTS

For all 84 patients, the median survival time was 12.5 months (range, 2-31.9 months), objective response (complete response or partial response) to CRT was observed in 28 patients (33.3%), and DM(3m) occurred in 24 patients (28.6%). Multivariate analysis showed that pretreatment CA 19-9 level (≤400 vs. >400 U/ml) was significantly associated with tumor response (45.1% vs. 15.2%), DM(3m) (19.6% vs. 42.4%), and median overall survival time (15.1 vs. 9.7 months) (p < 0.05 for all three parameters).

CONCLUSION

For patients with localized and unresectable pancreatic cancer, pretreatment CA 19-9 level could be helpful in predicting tumor response, DM(3m), and overall survival and identifying patients who will benefit from CRT.

CA 19-9 level as indicator of early distant metastasis and therapeutic selection in resected pancreatic cancer

PURPOSE

In patients with pancreatic cancer treated with curative resection, we evaluated the effect of clinicopathologic parameters on early distant metastasis within 6 months (DM6m) to identify patients who might benefit from surgery.

METHODS AND MATERIALS

The study involved 84 patients with pancreatic cancer who had undergone curative resection between August 2001 and April 2009. The parameters of gender, age, tumor size, histologic differentiation, T classification, N classification, pre- and postoperative carbohydrate antigen (CA) 19-9 level, resection margin, and adjuvant chemoradiotherapy were analyzed to identify the risk factors associated with DM6m.

RESULTS

Of the 84 patients, locoregional recurrence developed in 35 (41.7%) and distant metastasis in 58 (69%). Of the 58 patients with distant metastasis, DM6m had developed in 27 (46.6%). Multivariate analysis showed that preoperative CA 19-9 level was significantly associated with DM6m (p<.05). Of all 84 patients, DM6m was observed in 9.1%, 50%, and 80% of those with a preoperative CA 19-9 level of ≤100 U/mL, 101-400 U/mL, and >400 U/mL, respectively (p<.001).

CONCLUSIONS

The preoperative CA 19-9 level might be a useful predictor of DM6m and to identify those who would benefit from surgical resection.

Failure of normalization of CA19-9 following resection for pancreatic cancer is tantamount to metastatic disease

BACKGROUND

Multidisciplinary therapy for pancreatic cancer involves radical resection followed by gemcitabine-based chemotherapy. Carbohydrate antigen 19-9 (CA19-9), when elevated preoperatively, is a useful marker to monitor disease status following resection. However, little has been reported on outcomes of patients in whom CA19-9 never normalizes. We hypothesize that failure of CA19-9 normalization within 6 months is prognostically equivalent to metastatic disease.

METHODS

From our pancreatectomy database, we identified 93 patients with pancreatic adenocarcinoma and elevated CA19-9 prior to resection with levels recorded postoperatively. Patients were grouped based on normalization or persistent elevation of CA19-9 at 6 months after resection. CA19-9 levels normalized (≤35 u/ml) after resection in 38 (41%) and remained elevated in 55 (59%). Clinicopathologic characteristics were compared using Student's t-test and contingency table analyses. Survival curves were constructed using Kaplan-Meier method and compared by log-rank analysis. Cox regression was used to determine predictors of survival.

RESULTS

The two groups had comparable clinicopathologic characteristics except for nodal status and perineural invasion, which were higher in patients with persistently elevated CA19-9. Persistent CA19-9 conferred shorter median overall survival of 10.8 months compared with 23.8 months in patients with normalization (p < 0.001), which persisted when controlling for nodal status. Multivariate analysis demonstrated persistently elevated CA19-9 as the sole statistically significant negative predictor of survival [hazard ratio (HR) 2.20, p = 0.002].

CONCLUSIONS

Persistent CA19-9 elevation after pancreatectomy correlates with shorter survival analogous to unresected or metastatic disease and should be regarded as persistent disease regardless of radiographic findings. These patients should be considered for accrual to clinical trials or initiation of alternative therapy.

Primary mucinous adenocarcinoma of renal pelvis with carcinoembryonic antigen production

We report a case of primary mucinous adenocarcinoma of the renal pelvis associated with carcinoembryonic antigen (CEA) production. A 48-year-old woman was incidentally found to have an elevated serum CEA level. A series of examinations revealed a fat-containing tumor in the left kidney and excluded tumors in other sites. Radical nephrectomy was performed, and the histopathologic examination revealed a mucinous adenocarcinoma that was strongly positive for CEA. Postoperatively, her serum CEA level gradually returned to the normal range, and she had had no recurrence by 9 months postoperatively.

Cytokeratin fragments in the serum: their utility for the management of oral cancer

Head and neck squamous cell carcinoma (HNSCC) is the sixth most common malignancy and is a major cause of cancer morbidity and mortality worldwide. Oral cancer is the most predominant malignancy in the Indian subcontinent due to the widespread habits of chewing tobacco and related products. Patients with oral tumours have a high risk of early locoregional relapse. Early detection of disease progression remains a challenging task mainly due to the lack of adequate early prognostic markers. CEA, SCC Ag, CA-125, serum cytokeratin (CK) fragments, Cyfra 21-1 (CK 19), TPS (CK 18), TPA (CK 8, 18, and 19) etc. are being used as serum markers for the prediction of prognosis of various malignancies. This review presents the available literature on serum CK markers in different malignancies evaluates their utility in the management of oral cancer, and identifies the lacunae which need to be addressed to develop sensitive and specific assays for early detection of recurrence, prognosis, and treatment monitoring.

New insights into the role of age and carcinoembryonic antigen in the prognosis of colorectal cancer

The aim of this study was to verify through relative survival (an estimate of cancer-specific survival) the true prognostic factors of colorectal cancer. The study involved 506 patients who underwent locally radical resection. All the clinical, histological and laboratory parameters were prognostically analysed for both overall and relative survival. This latter was calculated from the expected survival of the general population with identical age, sex and calendar years of observation. Univariate and multivariate analyses were applied to the proportional hazards model. Liver metastases, age, lymph node involvement and depth of bowel wall involvement were independent prognosticators of both overall and relative survival, whereas carcinoembryonic antigen (CEA) was predictive only of relative survival. Increasing age was unfavourably related to overall survival, but mildly protective with regard to relative survival. Three out of the five prognostic factors identified are the cornerstones of the current staging systems, and were confirmed as adequate by the analysis of relative survival. The results regarding age explain the conflicting findings so far obtained from studies considering overall survival only and advise against the adoption of absolute age limits in therapeutic protocols. Moreover, the prechemotherapy CEA level showed a high clinical value.

Onset of Liver Metastasis After Histologically Curative Resection of Pancreatic Cancer

PURPOSE

We assessed the possibility of predicting the time of onset of liver metastases by measuring the postoperative changes in serum carbohydrate antigen (CA)19-9 after curative resection of pancreatic cancers.

METHODS

Among 28 patients who underwent histologically defined curative resection of pancreatic cancer between 1984 and 1999, liver metastasis developed in 11 patients with elevated serum CA19-9 levels. We plotted the serum CA19-9 levels against time on a semilogarithmic graph. Over the linear part of the curve, the time when log[CA19-9] equaled zero was defined as the time of onset of liver metastases. The log[CA19-9] level doubling time was then calculated and evaluated in relation to the survival period.

RESULTS

The serum CA19-9 levels increased linearly in 10 of the 11 patients. The predicted time of onset of liver metastasis ranged from preoperative day 163.0 to postoperative day 27.1, being preoperative in eight patients. The doubling time until death correlated strongly with survival in the eight patients with maintained log[CA19-9] linearity.

CONCLUSION

The onset of liver metastases might be preoperative in patients with advanced pancreatic cancer. Therefore, neoadjuvant chemotherapy should be mandatory even if there is no sign of liver metastases.

Pattern of carcinoembryonic antigen drop after laparoscopic radiofrequency ablation of liver metastasis from colorectal carcinoma

BACKGROUND

Laparoscopic radiofrequency ablation (RFA) is being increasingly used for local control of hepatic metastasis from colorectal carcinoma (CRC). After surgical resection of colorectal liver metastasis, carcinoembryonic antigen (CEA) values fall within 2 weeks, making this a useful parameter to follow shortly after surgery. Little is known, however, about the expected pattern of the CEA drop after RFA.

METHODS

From September 1998 to October 2002, RFA to CRC liver metastasis was performed on 144 patients. A subset of 17 patients were studied who had no evidence of extrahepatic disease preoperatively, had all detectable tumor ablated intraoperatively, and who on long-term follow-up (up to 15 months) had no evidence of recurrent disease. Serum CEA was determined preoperatively, on the first postoperative day, at 1 week, and every 3 months afterwards. A computed tomography (CT) scan of the abdomen and pelvis was obtained every 3 months postoperatively.

RESULTS

Ten (58.8%) patients showed an increase in CEA on postoperative Day 1, averaging 38.3% compared with the preoperative value. CEA then fell to 50% of the preoperative value, on average, on Day 7 postoperatively and only reached its nadir at 3 months.

CONCLUSIONS

Unlike resection patients, those undergoing ablation show an initial rise in CEA, probably due to release from the ablated tissue. Although heating of RFA would be expected to destroy CEA, the initial rise and slow drop postoperatively argue for a release of immunoreactive CEA from the ablated zone. This slow decline in CEA indicates that several months should pass before assessing the extent of potential residual disease.

Clinical utility of cytokeratins as tumor markers

Cytokeratins, belonging to the intermediate filament (IF) protein family, are particularly useful tools in oncology diagnostics. At present, more than 20 different cytokeratins have been identified, of which cytokeratins 8, 18, and 19 are the most abundant in simple epithelial cells. Upon release from proliferating or apoptotic cells, cytokeratins provide useful markers for epithelial malignancies, distinctly reflecting ongoing cell activity. It appears that motifs in certain cytokeratins make them likely substrates for caspase degradation, and their subsequent release occurs during the intermediate events in apoptosis. The clinical value of determining soluble cytokeratin protein fragments in body fluids lies in the early detection of recurrence and the fast assessment of the efficacy of therapy response in epithelial cell carcinomas. The three most applied cytokeratin markers used in the clinic are tissue polypeptide antigen (TPA), tissue polypeptide specific antigen (TPS), and CYFRA 21-1. TPA is a broad spectrum test that measures cytokeratins 8, 18, and 19. TPS and CYFRA 21-1 assays are more specific and measure cytokeratin 18 and cytokeratin 19, respectively. By following patients with repeated testing during management, the oncologist may obtain critical information regarding the growth activity in symptomatic patients. Although their main use is to monitor treatment and evaluate response to therapy, early prognostic information particularly on tumor progression and metastasis formation is also provided for several types of cancers. Cytokeratin tumor markers can accurately predict disease status before conventional methods and offer a simple, noninvasive, cheap, and reliable tool for more efficient management.