Disappearance Curves for Tumor Markers after Resection of Intrathoracic Malignancies

Prognosis prediction of PDAC via detection of O-glycan altered extracellular vesicles in perioperative sera

Pancreatic ductal adenocarcinoma (PDAC) is a fatal malignancy due to the difficulty in diagnosis and poor prognosis because of the high recurrence rate, necessitating reliable biomarkers to improve the diagnosis and prognosis. However, the existing markers have limitations. We previously identified extracellular vesicles (EVs) recognized by O-glycan-binding lectins (Amaranthus caudatus agglutinin [ACA]) as a novel diagnostic biomarker for PDAC using an EV-counting system (ExoCounter). This retrospective study analyzed changes in ACA-positive EVs in perioperative PDAC serum and its association with prognosis using ExoCounter. Absolute EV levels in the pre- and postoperative sera of 44 patients who underwent curative pancreatectomy for PDAC were quantified using ExoCounter. The carbohydrate antigen 19-9 levels declined in most samples postoperatively, and presented no correlation with poor prognosis. In contrast, ACA-positive EVs increased in serum at 7 days postoperatively in 27 of 44 patients (61.4%). We therefore divided participants with ACA-positive EVs before and after surgery into elevation and decline groups. The overall survival (OS) and recurrence-free survival (RFS) of patients with higher ACA-positive EVs were significantly shorter than those with lower ACA-positive EVs (26.1 months vs. not reached, P = 0.018; 11.9 vs. 38.6 months, P = 0.013). Multivariable analysis revealed that ACA-positive EV elevation in postoperative serum was an independent prognostic factor for poor OS (hazard ratio [HR] = 3.891, P = 0.023) and RFS (HR = 2.650, P = 0.024). The detection of ACA-positive EVs in perioperative serum may be used to predict the prognosis of PDAC in the early postoperative period.

Postoperative Carbohydrate Antigen 19-9 Level as a Good Indicator of Ineffective Response to the Currently Recommended S-1 Adjuvant Chemotherapy for Pancreatic Ductal Adenocarcinoma: A Single-Center, Retrospective Study

PURPOSE

The intensity of adjuvant treatment for pancreatic ductal adenocarcinomas (PDACs) has not been stratified according to the risk after resection. This study was designed to identify patients with PDACs in whom the current S-1 adjuvant treatment is ineffective.

METHODS

This single-center, retrospective study included patients who underwent pancreatectomy for PDACs from 2009 to 2020 at Sendai Open Hospital and were receiving S-1 adjuvant treatment. The independent risk factors for recurrence and survival were determined by using a Cox proportional hazards regression model. The effects of S-1 adjuvant treatment and detailed patterns of recurrence were evaluated in patients with high-risk factors.

RESULTS

Overall, 118 patients with PDAC received S-1 adjuvant treatment. Postoperative nonnormalized carbohydrate antigen (CA19-9) was a predictive risk factor for recurrence (p < 0.010; hazard ratio [HR], 3.87; 95% confidence interval [CI], 2.26-6.62) and survival (p = 0.008; HR, 2.25; 95% CI, 1.24-4.11) after S-1 adjuvant treatment. In 24 patients with nonnormalized postoperative CA19-9, S-1 monotherapy was ineffective in preventing recurrence, even during the treatment period, compared with that noted in patients who did not receive adjuvant treatment. The recurrence rate during adjuvant treatment was 41.7%; in all cases, recurrence was caused by distant metastasis. The total recurrence rate was up to 95.8%, and distant recurrence was especially frequent.

CONCLUSIONS

The current S-1 adjuvant treatment regimen is ineffective for patients with postoperative nonnormalized CA19-9. The postoperative CA19-9 level may be a good indicator for further aggressive treatment. This study may lead to further discussions on intensity stratification of adjuvant treatments for PDAC.

Clinical perspectives on serum tumor marker use in predicting prognosis and treatment response in advanced non-small cell lung cancer

The optimal positioning and usage of serum tumor markers (STMs) in advanced non-small cell lung cancer (NSCLC) care is still unclear. This review aimed to provide an overview of the potential use and value of STMs in routine advanced NSCLC care for the prediction of prognosis and treatment response. Radiological imaging and clinical symptoms have shown not to capture a patient's entire disease status in daily clinical practice. Since STM measurements allow for a rapid, minimally invasive, and safe evaluation of the patient's tumor status in real time, STMs can be used as companion decision-making support tools before start and during treatment. To overcome the limited sensitivity and specificity associated with the use of STMs, tests should only be applied in specific subgroups of patients and different test characteristics should be defined per clinical context in order to answer different clinical questions. The same approach can similarly be relevant when developing clinical applications for other (circulating) biomarkers. Future research should focus on the approaches described in this review to achieve STM test implementation in advanced NSCLC care.

Postoperative serum squamous cell carcinoma antigen and carcinoembryonic antigen predict overall survival in surgical patients with esophageal squamous cell carcinoma

Background

Tumor markers are routinely used in clinical practice. However, for resectable patients with esophageal squamous cell carcinoma (ESCC), they are applied infrequently as their prognostic significance is incompletely understood.

Methods

This historical cohort study included 2769 patients with resected ESCC from 2011 to 2018 in a high-risk area in northern China. Their clinical data were extracted from the Electronic Medical Record. Survival analysis of eight common tumor markers was performed with multivariable Cox proportional hazards regressions.

Results

With a median follow-up of 39.5 months, 901 deaths occurred. Among the eight target markers, elevated postoperative serum SCC (Squamous cell carcinoma antigen) and CEA (Carcinoembryonic antigen) predicted poor overall survival (SCC HRadjusted: 2.67, 95% CI: 1.70-4.17; CEA HRadjusted: 2.36, 95% CI: 1.14-4.86). In contrast, preoperative levels were not significantly associated with survival. Stratified analysis also demonstrated poorer survival in seropositive groups of postoperative SCC and CEA within each TNM stage. The above associations were generally robust using different quantiles of concentrations above the upper limit of the clinical normal range as alternative cutoffs. Regarding temporal trends of serum levels, SCC and CEA were similar. Their concentrations fell rapidly after surgery and thereafter remained relatively stable.

Conclusion

Postoperative serum SCC and CEA levels predict the overall survival of ESCC surgical patients. More importance should be attached to the use of these markers in clinical applications.

Circulating Nucleic Acids as Novel Biomarkers for Pancreatic Ductal Adenocarcinoma

Despite considerable advancements in the clinical management of PDAC it remains a significant cause of mortality. PDAC is often diagnosed at advanced stages due to vague symptoms associated with early-stage disease and a lack of reliable diagnostic biomarkers. Late diagnosis results in a high proportion of cases being ineligible for surgical resection, the only potentially curative therapy for PDAC. Furthermore, a lack of prognostic biomarkers impedes clinician's ability to properly assess the efficacy of therapeutic interventions. Advances in our ability to detect circulating nucleic acids allows for the advent of novel biomarkers for PDAC. Tumor derived circulating and exosomal nucleic acids allow for the detection of PDAC-specific mutations through a non-invasive blood sample. Such biomarkers could expand upon the currently limited repertoire of tests available. This review outlines recent developments in the use of molecular techniques for the detection of these nucleic acids and their potential roles, alongside current techniques, in the diagnosis, prognosis and therapeutic governance of PDAC.

Prognostic Value of Carbohydrate Antigen 19-9 and the Surgical Margin in Extrahepatic Cholangiocarcinoma

Aim

The prognostic value of the perioperative carbohydrate antigen 19-9 (CA19-9) value and the prognostic relationship between the CA19-9 value and the surgical margin in extrahepatic cholangiocarcinoma (EHCC) have not been fully discussed.

Methods

A total of 390 patients who underwent curative resection for EHCC between 2002 and 2018 were retrospectively analyzed. According to the perioperative CA19-9 value, patients were divided into three groups: preoperative normal (Normal, n = 178), preoperative high and postoperative normal (Normalization, n = 155), and preoperative high and postoperative high (Nonnormalization, n = 57). Survival was analyzed according to the perioperative CA19-9 value and surgical margin.

Results

The optimal cutoff value of CA19-9 was 37 U/mL. Overall survival (OS) was significantly stratified according to the perioperative CA19-9 value. The 5-y OS rates in the Normal, Normalization, and Nonnormalization groups were 53%, 38%, and 23%, respectively (P < .001). Although the locoregional recurrence rate was comparable among the groups, the Normal group exhibited distant recurrence less frequently in comparison to the other groups. In the Normal group, the margin status had a significant impact on the OS (surgical resection with a negative margin [R0], 59% vs a microscopically positive margin [R1], 7% at 5-y, P < .001). In contrast, in the Normalization and Nonnormalization groups, the OS rate of the R0 and R1 resection groups did not differ to a statistically significant extent.

Conclusion

The perioperative CA19-9 value was related to the prognosis of resectable EHCC. A preoperative CA19-9 value of ≥37 U/mL reflected systemic disease. R0 resection did not affect the survival in this patient group.

Liquid Biopsy: A Distinctive Approach to the Diagnosis and Prognosis of Cancer

Cancer is a leading cause of morbidity and mortality worldwide. Over the past decades, the concept of precision cancer medicine has emerged as a novel approach in the field of oncology that aims to tailor the most effective treatment options to each individual cancer patient based on the genetic profile of the tumor of each individual patient. Recently, tissue biopsy has become an essential part of cancer care and is widely used to characterize the tumor. However, tissue biopsy techniques face different challenges due to their invasiveness, cost, time, and adversity in potential sampling due to tissue heterogeneity. To overcome these issues, a non-invasive approach has developed, which is known as liquid biopsy. It is a simple, fast, and worthwhile technique based on the analysis of circulating tumor DNA (which is a fraction of cfDNA), circulating tumor cells (CTCs), and other tumor-derived material in blood plasma. This review provides an overview of the concept of liquid biopsy and briefly discusses the role of ctDNA and CTC analysis as tools for early diagnosis and prognosis of cancer. In this review, we also speculate on the advantages of liquid biopsy as opposed to tissue biopsy and postulate that liquid biopsy may be a comprehensive approach to overcome the current limitations associated with costly, invasive, and time-consuming tissue biopsy.

Prognostic value of tumor markers and ctDNA in patients with resectable gastric cancer receiving perioperative treatment: results from the CRITICS trial

AIM

To evaluate the prognostic value of tumor markers in a European cohort of patients with resectable gastric cancer.

METHODS

We performed a post hoc analysis of the CRITICS trial, in which 788 patients received perioperative therapy. Association between survival and pretreatment CEA, CA 19-9, alkaline phosphatase, neutrophils, hemoglobin and lactate dehydrogenase were explored in uni- and multivariable Cox regression analyses. Likelihoods to receive potentially curative surgery were investigated for patients without elevated tumor markers versus one of the tumor markers elevated versus both tumor markers elevated. The association between tumor markers and the presence of circulating tumor DNA (ctDNA) was explored in 50 patients with available ctDNA data.

RESULTS

In multivariable analysis, in which we corrected for allocated treatment and other baseline characteristics, elevated pretreatment CEA (HR 1.43; 95% CI 1.11-1.85, p < 0.001) and CA 19-9 (HR 1.79; 95% CI 1.42-2.25, p < 0.001) were associated with worse OS. Likelihoods to receive potentially curative surgery were 86%, 77% and 60% for patients without elevated tumor marker versus either elevated CEA or CA 19-9 versus both elevated, respectively (p < 0.001). Although both preoperative presence of ctDNA and tumor markers were prognostic for survival, no association was found between these two parameters.

CONCLUSION

CEA and CA 19-9 were independent prognostic factors for survival in a large cohort of European patients with resectable gastric cancer. No relationship was found between tumor markers and ctDNA. These factors could potentially guide treatment choices and should be included in future trials to determine their definitive position.

TRIAL REGISTRATION

ClinicalTrial.gov identifier: NCT00407186. EudraCT number: 2006-00413032.

Increased circulating cytokeratin 19 fragment levels in preterm neonates receiving mechanical ventilation are associated with poor outcome

Invasive mechanical ventilation and oxygen toxicity are postnatal contributors to chronic lung disease of prematurity, also known as bronchopulmonary dysplasia (BPD). Cyfra 21-1 is a soluble fragment of cytokeratin 19, which belongs to the cytoskeleton stabilizing epithelial intermediate filaments. As a biomarker of structural integrity, Cyfra 21-1 might be associated with airway injury and lung hypoplasia in neonates. Serum Cyfra 21-1 concentrations for 80 preterm and 80 healthy term newborns were measured within 48 h after birth. Preterm infants with the combined endpoint BPD/mortality had significantly higher Cyfra 21-1 levels compared with those without fulfilling BPD/mortality criteria (P = 0.01). Also, severe RDS (>grade III) was associated with higher Cyfra levels (P = 0.01). Total duration of oxygen therapy was more than five times longer in neonates with high Cyfra 21-1 levels (P = 0.01). Infants with higher Cyfra 21-1 values were more likely to receive mechanical ventilation (50% vs. 17.5%). However, the duration of mechanical ventilation was similar between groups. The median Cyfra value was 1.93 ng/mL (IQR: 1.68-2.53 ng/mL) in healthy term neonates and 8.5 ng/mL (IQR: 3.6-16.0 ng/mL) in preterm infants. Using ROC analysis, we calculated a Cyfra cutoff > 8.5 ng/mL to predict BPD/death with an AUC of 0.795 (P = 0.004), a sensitivity of 88.9%, and a specificity of 55%. Mortality was predicted with a cutoff > 17.4 ng/mL (AUC: 0.94; P = 0.001), a sensitivity of 100%, and a specificity of 84%. These findings suggest that Cyfra 21-1 concentration might be useful to predict poor outcome in premature infants.

A Serum Level of Squamous Cell Carcinoma Antigen as a Real-Time Biomarker of Atopic Dermatitis

Background: Although serum levels of squamous cell carcinoma antigen (SCCA) are elevated in atopic dermatitis (AD), their clinical utility has not been fully elucidated. Methods: Thirty-three cases of AD who admitted to our hospital were analyzed. Results: Baseline characteristics on admission were as follows: median age 19 months [interquartile range (IQR), 12-52 months], median objective severity scoring of atopic dermatitis (O-SCORAD) 19.2 (IQR, 4.2-36.0), and median serum SCCA levels 3.2 ng/mL (IQR, 2.1-6.8 ng/mL). O-SCORAD significantly correlated with serum SCCA levels (rs = 0.865, P < 0.001). In 9 cases whose information before and after treatment was available (median interval, 3 days; IQR 2-5 days), median serum SCCA levels significantly decreased from 8.0 to 2.0 ng/mL (P = 0.008) after the treatment. Conclusions: Serum levels of total SCCA rapidly declined in response to the treatment and could be used as a real-time biomarker in childhood AD.

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.

A case of Trousseau's syndrome due to intrahepatic cholangiocarcinoma with an extremely high level of CA19-9

BACKGROUND

Trousseau's syndrome is a cancer-associated thrombosis. Trousseau's syndrome with cholangiocarcinoma is a rare condition with poor prognosis.

CASE PRESENTATION

A 59-year-old female was admitted to our hospital with abdominal pain, headache, and nausea. Abdominal enhanced computed tomography revealed liver tumor, splenic infarction, and bilateral renal infarction. Multiple acute cerebral infarctions were also detected by magnetic resonance imaging. Her preoperative serum levels of carbohydrate antigen 19-9 (CA19-9) and carcinoembryonic antigen (CEA) were > 120,000 U/mL and 589.6 ng/mL, respectively, which were extremely high. Histopathology after right hepatectomy revealed moderately differentiated adenocarcinoma consistent with intrahepatic cholangiocarcinoma. Her serum levels of CA19-9 were trending down to 9029.2 and 2659.8 U/mL at 1 and 3 weeks after surgery, respectively. However, at 7 weeks after surgery, her CA19-9 levels increased in the presence of positive imaging findings in the remnant liver, hilar lymph nodes, and peritoneal cavity. The initiation of combination chemotherapy including gemcitabine and cisplatin had a significant effect. The patient was doing well at 6 months after the surgery.

CONCLUSION

This rare case of Trousseau's syndrome due to cholangiocarcinoma suggests that extremely high CA19-9 levels might be a pathogenic factor of this syndrome.

CEA clearance pattern as a predictor of tumor response to neoadjuvant treatment in rectal cancer: a post-hoc analysis of FOWARC trial

BACKGROUND

The clinical factors that accurately predict the response to preoperative treatment in rectal cancer were yet unknown. The carcinoembryonic antigen (CEA) clearance pattern during neoadjuvant treatment has been developed and the predictive value explored in rectal cancer patients with elevated CEA levels (> 5 ng/mL).

METHODS

The training cohort was derived from the FOWARC prospective phase III trial, and 71/483 eligible patients were included. The validation cohort consisted of 75/587 consecutive rectal cancer patients from Xiangya Hospital between 2014 and 2015. The kinetic changes in serum CEA were measured at different time points during the neoadjuvant treatment. An exponential trend line was drawn using the CEA values. The patients were categorized into two groups based on the R² value of the trend line, which indicates the correlation coefficient between the exponential graph and measured CEA values: exponential decrease group (0.9 < R² ≤ 1.0) and non-exponential decrease group (R² ≤ 0.9).

RESULTS

In multivariate analysis, the patients in the CEA exponential decrease group had significantly high adequate rate of downstaging (ypT0-2N0M0), and pathologic complete response (pCR) rates after neoadjuvant treatment in the training cohort. The predictive values of the CEA clearance pattern for tumor downstaging and pCR were further confirmed in an independent validation cohort.

CONCLUSIONS

The CEA clearance pattern was an independent predictor of tumor response to neoadjuvant treatment in patients with rectal cancer. It might serve as an adjunct in the assessment of complete clinical response and guide individualized treatment strategies.

TRIAL REGISTRATION

NCT01211210.

Clinical Interest of Circulating Tumor DNA in Oncology

Genetic alterations in tumors, as predictor of response to targeted-therapies or as prognostic markers, are clinically relevant to determine adequate therapeutic management. Tumor biopsy is currently the golden standard for somatic alterations assessment, but this approach is invasive and does not consider tumor heterogeneity. In various body fluids like plasma, somatic mutations have been identified. Circulating tumor DNA (ctDNA) holds promises in tumor burden monitoring or malignancies early detection. Since allele frequencies of circulating somatic mutations are low, highly sensitive novel assays have been developed to allow the investigation of the tumor genome, leading to the emergence of the "liquid biopsy" concept. Despite these technological advances, other assays for identifying intratumor and intermetastases heterogeneity need to be developed. Before being applied to clinic, ctDNA analyses need to be harmonized and validated with well-powered, well-designed studies. One of the primary prerequisite to incorporation of ctDNA analysis in the follow-up strategy of malignancies is the checking of the concordance with golden standard detection methods, imaging, circulating proteins and biopsy. This review focuses on the clinical interest of ctDNA in solid tumors and hematological malignancies.

Application of liquid biopsy in bone and soft tissue sarcomas: Present and future

Bone and soft tissue sarcomas account for approximately 1% of adult solid malignancies and 20% of pediatric solid malignancies. Sarcomas are divided into more than 50 subtypes. Each subtype is highly heterogeneous and characterized by significant morphological and phenotypic variability. Currently, sarcoma characterization is based on tissue biopsies. However, primary and invasive tissue biopsies may not accurately reflect the current disease condition following treatment as is may cause marked changes to the tumor cells. Liquid biopsy offers an alternative minimally invasive approach to provide dynamic tumor information, allowing for the application of precision medicine in the treatment of sarcomas. Recently, there have been numerous blood-based tumor components identified by liquid biopsy in sarcomas, including circulating tumor cells, circulating cell-free nucleic acids, tumor-derived exosomes and metabolites in circulation. Here, we summarize the current evolving technologies and then elaborate on emerging novel concepts that may further propel the field of liquid biopsy in sarcomas. We address the applications in the context of our current knowledge about liquid biopsy in sarcomas and highlight the potential of translating these recent advances into the clinic for more effective management strategies for sarcoma patients.

Mutant KRAS Circulating Tumor DNA Is an Accurate Tool for Pancreatic Cancer Monitoring

BACKGROUND

Many new pancreatic cancer treatment combinations have been discovered in recent years, yet the prognosis of pancreatic ductal adenocarcinoma (PDAC) remains grim. The advent of new treatments highlights the need for better monitoring tools for treatment response, to allow a timely switch between different therapeutic regimens. Circulating tumor DNA (ctDNA) is a tool for cancer detection and characterization with growing clinical use. However, currently, ctDNA is not used for monitoring treatment response. The high prevalence of KRAS hotspot mutations in PDAC suggests that mutant KRAS can be an efficient ctDNA marker for PDAC monitoring.

SUBJECTS, MATERIALS, AND METHODS

Seventeen metastatic PDAC patients were recruited and serial plasma samples were collected. CtDNA was extracted from the plasma, and KRAS mutation analysis was performed using next-generation sequencing and correlated with serum CA19-9 levels, imaging, and survival.

RESULTS

Plasma KRAS mutations were detected in 5/17 (29.4%) patients. KRAS ctDNA detection was associated with shorter survival (8 vs. 37.5 months). Our results show that, in ctDNA positive patients, ctDNA is at least comparable to CA19-9 as a marker for monitoring treatment response. Furthermore, the rate of ctDNA change was inversely correlated with survival.

CONCLUSION

Our results confirm that mutant KRAS ctDNA detection in metastatic PDAC patients is a poor prognostic marker. Additionally, we were able to show that mutant KRAS ctDNA analysis can be used to monitor treatment response in PDAC patients and that ctDNA dynamics is associated with survival. We suggest that ctDNA analysis in metastatic PDAC patients is a readily available tool for disease monitoring.

IMPLICATIONS FOR PRACTICE

Avoiding futile chemotherapy in metastatic pancreatic ductal adenocarcinoma (PDAC) patients by monitoring response to treatment is of utmost importance. A novel biomarker for monitoring treatment response in PDAC, using mutant KRAS circulating tumor DNA (ctDNA), is proposed. Results, although limited by small sample numbers, suggest that ctDNA can be an effective marker for disease monitoring and that ctDNA level over time is a better predictor of survival than the dynamics of the commonly used biomarker CA19-9. Therefore, ctDNA analysis can be a useful tool for monitoring PDAC treatment response. These results should be further validated in larger sample numbers.

Tumor DNA: an emerging biomarker in head and neck cancer

Head and neck cancer (HNC) includes a diverse range of malignancies arising commonly from mucosal epithelia of the upper aerodigestive tract. Head and neck squamous cell carcinoma (HNSCC), the most common form of HNC, develops in the oral cavity, pharynx, and larynx and is associated with tobacco exposure, alcohol abuse, and infection with oncogenic viruses. Despite global advances in cancer care, HNSCC often presents with advanced disease and is associated with poor 5-year survival of ~50%. Genotyping tumor tissue to guide clinical decision-making is becoming commonplace in modern oncology, but in the management of HNSCC, tissue biopsies with cytopathology or histopathology remain the mainstay for diagnosis. Furthermore, conventional biopsies are temporally and spatially limited, often providing a brief snapshot of a single region of a heterogeneous tumor. In the absence of a useful biomarker, both primary and recurrent HNSCCs are diagnosed with conventional imaging and clinical examination. As a result, many patients are diagnosed with advanced disease. Tumor DNA is an emerging biomarker in HNSCC. DNA fragments are constantly being shed from tumors and metastatic lesions, and can therefore be detected in blood and other bodily fluids. Utilizing next-generation sequencing techniques, these tumor DNA can be characterized and quantified. This can serve as a minimally invasive liquid biopsy allowing for specific tumor profiling, dynamic tumor burden monitoring, and active surveillance for disease recurrences. In HNSCC, analysis of tumor DNA has the potential to enhance tumor profiling, aid in determining patient prognosis, and guide treatment decisions.

Prognostic value of carbohydrate antigen 19-9 in patients undergoing resection of biliary tract cancer

BACKGROUND

The clinical significance of abnormally high levels of carbohydrate antigen (CA) 19-9 after resection of biliary tract cancer (BTC) is not well established. The aim of this study was to determine the prognostic value of CA19-9 normalization in patients undergoing resection of BTC with curative intent.

METHODS

Patients with BTC undergoing resection with curative intent (1996-2015) were divided into those with normal preoperative CA19-9 level (normal CA19-9 group), those with an abnormally high preoperative CA19-9 level (over 37 units/ml) and normal postoperative CA19-9 level (normalization group), and those with an abnormally high preoperative CA19-9 level and abnormally high postoperative CA19-9 level (non-normalization group). Overall survival (OS) was analysed and predictors of OS were determined.

RESULTS

The normal CA19-9 group (180 patients) and normalization group (74) had better OS than the non-normalization group (58) (3-year OS rate 70·4, 73 and 31 per cent respectively; both P < 0·001). The normal CA19-9 and normalization groups had equivalent OS (P = 0·880). On multivariable analysis, factors associated with worse OS were lymph node metastases (hazard ratio (HR) 1·78; P = 0·014) and abnormally high postoperative CA19-9 level (HR 3·16; P < 0·001). In the normalization group, OS did not differ after R0 versus R1 resection (3-year OS rate 69 versus 62 per cent respectively; P = 0·372); in the non-normalization group, patients with R1 resection had worse OS (3-year OS rate 36 and 20 per cent for R0 and R1 respectively; P = 0·032).

CONCLUSION

Non-normalization of CA19-9 level after resection of BTC with curative intent was associated with worse OS. R1 resection was associated with a particularly poor prognosis when CA19-9 levels did not normalize.

Time to lowest postoperative carcinoembryonic antigen level is predictive on survival outcome in rectal cancer

This study was to investigate whether the time to the lowest postoperative CEA can predict cancer survival. We enrolled 155 rectal cancer patients in this retrospective and longitudinal cohort study. Deepness of response (DpR) of CEA refers to the relative change of the lowest postoperative CEA level from baseline, and time to DpR (TTDpR) refers to the time from surgery to the lowest postoperative CEA level. The median of TTDpR and DpR was 4.5 (range, 3.0-18.0) weeks and -67% (range, -99% to 114%) respectively. Patients with TTDpR </ = 4.5 weeks had better 3-year DFS (81.4% vs. 76.2%; P = 0.059) and OS (95.8% vs. 87.9%; P = 0.047) rate than patients with TTDpR >4.5 weeks. Using TTDpR as a continuous variable, the HR of DFS and OS was 1.13 (95% CI 1.06-1.22, P = 0.001) and 1.17 (95% CI 1.07-1.29, P = 0.001) respectively. On multivariate analysis, the predictive value of prolonged TTDpR remained [adjusted HRs: 1.12 (95% CI 1.03-1.21, P = 0.006) and 1.17 (95% CI 1.06-1.28, P = 0.001)]. These findings remained significant in patients with normal preoperative CEA. Our results showed prolonged TTDpR of CEA independently predicted unfavorable survival outcomes, regardless of whether preoperative CEA was elevated or not.

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.

Cell-free circulating tumor DNA in cancer

Cancer is a common cause of death worldwide. Despite significant advances in cancer treatments, the morbidity and mortality are still enormous. Tumor heterogeneity, especially intratumoral heterogeneity, is a significant reason underlying difficulties in tumor treatment and failure of a number of current therapeutic modalities, even of molecularly targeted therapies. The development of a virtually noninvasive “liquid biopsy” from the blood has been attempted to characterize tumor heterogeneity. This review focuses on cell-free circulating tumor DNA (ctDNA) in the bloodstream as a versatile biomarker. ctDNA analysis is an evolving field with many new methods being developed and optimized to be able to successfully extract and analyze ctDNA, which has vast clinical applications. ctDNA has the potential to accurately genotype the tumor and identify personalized genetic and epigenetic alterations of the entire tumor. In addition, ctDNA has the potential to accurately monitor tumor burden and treatment response, while also being able to monitor minimal residual disease, reducing the need for harmful adjuvant chemotherapy and allowing more rapid detection of relapse. There are still many challenges that need to be overcome prior to this biomarker getting wide adoption in the clinical world, including optimization, standardization, and large multicenter trials.

Developing biomarker-specific end points in lung cancer clinical trials

In cancer-drug development, a number of different end points have been used to establish efficacy and support regulatory approval, such as overall survival, progression-free survival (PFS), and radiographic response rate. However, these traditional end points have important limitations. For example, in lung cancer clinical trials, evaluating overall survival end points is a protracted process and these end points are most reliable when crossover to the investigational therapy is not permitted. Furthermore, although radiographic surrogate end points, such as PFS and response rate, generally correlate with clinical benefit in the setting of cytotoxic chemotherapy and molecular targeted therapies, novel immunotherapies might have atypical response kinetics, which confounds radiographic interpretation. In this Review, we discuss the need to develop alternative or surrogate end points for lung cancer clinical trials, and focus on several new biomarkers that could serve as surrogate end points, including functional imaging biomarkers, circulating factors (tumour proteins, DNA, and cells), and pharmacodynamic tumour markers. By enabling the size, duration, and complexity of cancer trials to be reduced, biomarker end points hold the promise to accelerate drug development and improve patient outcomes.

Elevated perioperative serum CA 19-9 levels are independent predictors of poor survival in patients with resectable cholangiocarcinoma

BACKGROUND AND OBJECTIVES

Identification of prognostic markers is important to establish a perioperative therapeutic strategy for resectable cholangiocarcinoma (CC). The aim of this study was to investigate whether perioperative serum carbohydrate antigen 19-9 (CA19-9) levels can predict survival of patients who underwent surgical resection for CC.

METHODS

The study included 106 patients who underwent surgical resection for CC. Serum CA19-9 levels were measured preoperatively after biliary drainage and postoperatively about 4 weeks after surgery. The association of clinicopathological factors (including perioperative serum CA19-9 levels) with overall survival (OS) was analyzed with univariate and multivariate analyses.

RESULTS

Differences in OS were significant between groups divided on the basis of two preoperative CA19-9 cutoff values (in U/ml) of 37 and 200 and three postoperative CA19-9 cutoff values (in U/ml) of 37, 100, and 200. In multivariate analysis, absence of postoperative adjuvant chemotherapy (P = 0.002), lymph node metastasis (P = 0.0002), preoperative CA19-9 (≥ 200 IU/ml) (P = 0.03), and postoperative CA19-9 (≥ 37 IU/ml) (P < 0.0001) were identified as independent predictors of poor OS.

CONCLUSION

Both pre- and postoperative serum CA19-9 levels predict the survival of patients with resectable CC, and may contribute to the establishment of a new therapeutic strategy.

Humoral autoimmune responses to insulin-like growth factor II mRNA-binding proteins IMP1 and p62/IMP2 in ovarian cancer

Ovarian cancer is one of the leading causes of cancer-related deaths among women. There is an urgent need of better approaches for the identification of appropriate biomarkers in the early detection of ovarian cancer. The aim of this study was to elucidate the significance of autoantibodies against insulin-like growth factor II mRNA-binding proteins (IMPs) in patients with ovarian cancer. In this study, autoantibody responses to two members (IMP1 and p62/IMP2) of IMPs were evaluated by enzyme-linked immunosorbent assay (ELISA), western blotting, and indirect immunofluorescence assay in sera from patients with ovarian cancer and normal human individuals. The results have demonstrated that both IMP1 and p62/IMP2 can induce relatively higher frequency of autoantibody responses in patients with ovarian cancer (26.5% and 29.4%) compared to normal individuals (P<0.01). Our preliminary data suggest that IMP1 and p62/IMP2 can stimulate autoimmune responses in ovarian cancer, and anti-IMP1 and anti-p62/IMP2 autoantibodies could be used as potential biomarkers in immunodiagnosis of ovarian cancer.

Liquid biopsies: genotyping circulating tumor DNA

Genotyping tumor tissue in search of somatic genetic alterations for actionable information has become routine practice in clinical oncology. Although these sequence alterations are highly informative, sampling tumor tissue has significant inherent limitations; tumor tissue is a single snapshot in time, is subject to selection bias resulting from tumor heterogeneity, and can be difficult to obtain. Cell-free fragments of DNA are shed into the bloodstream by cells undergoing apoptosis or necrosis, and the load of circulating cell-free DNA (cfDNA) correlates with tumor staging and prognosis. Moreover, recent advances in the sensitivity and accuracy of DNA analysis have allowed for genotyping of cfDNA for somatic genomic alterations found in tumors. The ability to detect and quantify tumor mutations has proven effective in tracking tumor dynamics in real time as well as serving as a liquid biopsy that can be used for a variety of clinical and investigational applications not previously possible.

Detection of a soluble form of CD109 in serum of CD109 transgenic and tumor xenografted mice

CD109, a glycosylphosphatidylinositol-anchored glycoprotein, is expressed at high levels in some human tumors including squamous cell carcinomas. As CD109 is reportedly cleaved by furin and its soluble form is secreted into culture medium in vitro, we hypothesized that CD109 could serve as a tumor marker in vivo. In this study, we investigated CD109 as a novel serum tumor marker using transgenic mice that overexpress mouse CD109 (mCD109-TG mice) and tumor xenografted mice inoculated with human CD109 (hCD109)-overexpressing HEK293 cells. In sera and urine of mCD109-TG mice, mCD109 was detected using western blotting. In xenografted mice, hCD109 secreted from inoculated tumors was detected in sera, using western blotting and CD109 ELISA. Concentrations of tumor-secreted CD109 increased proportionally as tumors enlarged. Concentrations of secreted CD109 decreased notably by 17 h after tumor resection, and became undetectable 48 h after resection. The half-life of tumor-secreted CD109 was about 5.86±0.17 h. These results indicate that CD109 is present in serum as a soluble form, and suggest its potential as a novel tumor marker in patients with cancers that express CD109.

CYFRA 21-1 as a disease severity marker for autoimmune pulmonary alveolar proteinosis

BACKGROUND AND OBJECTIVE

Serum markers, including Krebs von den Lungen (KL-6), surfactant protein (SP)-D, SP-A and carcinoembryonic antigen (CEA), are reported to reflect autoimmune pulmonary alveolar proteinosis (APAP) disease severity. We evaluated serum CYFRA21-1 levels as a marker of APAP.

METHODS

In addition to KL-6, SP-D and CEA, we prospectively measured serum CYFRA 21-1 levels in 48 patients with APAP, consecutively diagnosed between 2002 and 2010. Diagnostic usefulness of CYFRA 21-1 was determined from 68 patients with interstitial lung diseases by receiver operator characteristic curve analysis. We evaluated the association between these serum markers and other disease severity markers, including pulmonary function parameters, alveolar-arterial oxygen gradient, British Medical Research Council score reflecting shortness of breath, and disease severity score. CYFRA 21-1 localization in the lung was examined by immunohistochemistry.

RESULTS

Receiver operator characteristic curve demonstrated that CYFRA 21-1 effectively identified APAP. Serum CYFRA 21-1 levels at diagnosis were significantly associated with the measured disease severity parameters. Following whole lung lavage (n = 10) and granulocyte-macrophage colony-stimulating factor (GM-CSF) inhalation (n = 20), serum CYFRA 21-1 levels were significantly decreased. Responders (n = 11) to GM-CSF inhalation revealed significantly higher serum CYFRA 21-1 levels than non-responders (n = 9). Serum CYFRA 21-1 appeared to be a significant predictor of effectiveness of GM-CSF based on regression analysis. Immunohistochemistry showed that CYFRA 21-1 was localized on hyperplastic alveolar type II cells and lipoproteinaceous substances in alveoli.

CONCLUSIONS

Serum CYFRA 21-1 is a sensitive and useful serum marker for diagnosis and evaluation of disease severity of APAP, and may predict the response to GM-CSF inhalation.

High serum levels of both carcinoembryonic antigen and carbohydrate antigen 19-9 in a patient with sigmoid colon cancer without metastasis

Carcinoembryonic antigen (CEA) and carbohydrate antigen (CA)19-9 are well known as the most common tumor markers of colon cancer, and levels are used not only for preoperative assessment of extent and outcome of cancer, but also postoperative monitoring of recurrence. We encountered a patient with sigmoid colon cancer showing abnormally high serum levels of CEA (311.1 ng/ml) and CA19-9 (5731.2 U/ml) preoperatively. We could not detect any metastases on computed tomography (CT) or (18)F-fluorodeoxyglucose positron emission tomography/CT. Sigmoidectomy and lymph node dissection were performed. Pathological analysis revealed well-differentiated tubular adenocarcinoma of the sigmoid colon with cancer cells infiltrating to the subserosa, but no lymph node metastases. As of postoperative day 60, serum levels of CEA and CA19-9 were 3.4 ng/ml and 9.2 U/ml, respectively, without any further anti-tumor treatment. This represents a rare case of sigmoid colon cancer with high levels of tumor markers in sera that improved following sigmoidectomy without further anti-cancer treatment.

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 perioperative serum CA 19-9 levels in patients with resectable pancreatic cancer

BACKGROUND

Pancreatic cancer is one of the most deadly cancers, and serum carbohydrate antigen 19-9 (CA19-9) level has been reported to be a useful prognostic marker in pancreatic cancer. The purpose of this study was to determine which prognostic factor (preoperative or postoperative serum CA19-9 level) is more useful.

METHODS

Pre- and postoperative serum CA19-9 levels were measured in 109 patients who underwent surgical resection for pancreatic cancer between 1998 and 2009, and their relationships to clinicopathological factors and overall survival were analyzed with univariate and multivariate methods.

RESULTS

In univariate analysis, tumor location (P = 0.019), postoperative adjuvant chemotherapy (P < 0.001), residual tumor factor status (P < 0.001), UICC pT stage (P = 0.004), lymph node metastasis (P = 0.015), and UICC final stage (P = 0.015) were significantly associated with overall survival. Differences in overall survival were significant between groups divided on the basis of four postoperative CA19-9 cutoff values (37, 100, 200, and 500 U/ml) but not significant between groups divided on the basis of the same four preoperative CA19-9 cutoff values. Pre- to postoperative increase in CA19-9 level also was significantly associated with poor prognosis. In multivariate analysis, postoperative adjuvant chemotherapy (hazard ratio, 1.59; P = 0.004) and postoperative CA19-9 cutoff value of 37 U/ml (HR, 1.64; P = 0.004) remained independent predictors of prognosis.

CONCLUSIONS

Postoperative CA19-9 level is a better prognostic factor than preoperative CA19-9 level, and curative surgery for resectable pancreatic cancer should be tried regardless of the preoperative CA19-9 level.

Clinical significance of CEA and CA19-9 in postoperative follow-up of colorectal cancer

BACKGROUND

We evaluated the efficiency of CEA and CA19-9 as tools for diagnosing recurrence in the postoperative surveillance of colorectal cancer.

MATERIALS AND METHODS

A total of 227 patients who underwent curative resection for colorectal cancer between 1999 and 2003 at our hospital received complete follow-up according to the schedule determined prospectively. Using receiver operating characteristic (ROC) analysis, performance of postoperative values of CEA or CA19-9 for detecting recurrence was assessed.

RESULTS

The sensitivity (1.000) and specificity (0.978) of the postoperative values of CEA in the high preoperative CEA group were very high. Even in the normal preoperative CEA group, the area under the curve (AUC) of the ROC curve of CEA (0.740, 95% confidence interval [95% CI], 0.628-0.852) was significantly larger than 0.5 (P < 0.001). The postoperative values of CA19-9 showed high sensitivity (0.833) and specificity (0.900) in the high preoperative CA19-9 group, while the AUC of the ROC curve of the normal preoperative group was as small as 0.510 (95% CI, 0.376-0.644). In the high preoperative CA19-9 group, however, there was no significant difference between the AUC of CA19-9 (0.904, 95% CI, 0.786-1.000) and that of CEA (0.869, 95% CI, 0.744-0.994) (P = 0.334).

CONCLUSIONS

The measurement of CEA is an efficient way to detect recurrence. The efficiency of measuring CA19-9 for the purpose of detecting recurrence is low, especially in patients with a normal level of preoperative CA19-9. Even in patients with a high preoperative level of CA19-9, CEA might be able to fill the role of CA19-9.

Characterization of humoral responses of ovarian cancer patients: antibody subclasses and antigenic components

OBJECTIVES

Current antigen-based diagnostic assays for ovarian cancers rely on intravasation of specific aberrantly expressed proteins and their achieving detectable steady-state concentrations, resulting in their inability to truly detect small early lesions. In contrast, tumor antigen immunorecognition is observed following initial transformation events. Our objective was to characterize humoral antitumor responses in terms of IgG subclasses generated and tumor antigens recognized.

METHODS

For patients with benign and malignant ovarian disease, tumor-reactive IgG subclasses were characterized by Western immunoblotting. Antigen recognition patterns were analyzed by 2-dimensional electrophoresis and proteins exhibiting shared or stage-specific recognition were defined by mass spectrometry (MS) sequencing.

RESULTS

Sera from ovarian cancer patients exhibited significantly greater immunoreactivities than either controls or women with benign disease. While late-stage patients recognized more proteins at greater intensity, stage-specific differential recognition patterns were observed in the IgG subclasses, with the greatest recognition appearing in IgG2 subclasses. Immunoreactivity in IgG2 and IgG3 from stage I and II patients appears to be most intense with nuclear antigens >40 kDa, while, in stage III patients, additional immunoreactivity was present in the <40 kDa components. Stage III patients also exhibited similar reaction with membrane antigens <40 kDa. Two-dimensional electrophoresis revealed 32 stage-linked antigenic differences with 11 in early-stage and 21 in late-stage ovarian cancer.

CONCLUSIONS

Owing to the timing and stability of humoral responses, quantitation of IgG subclasses recognizing specific tumor antigens provides superior biomarkers for early cancer identification and allows for differentiation of benign versus malignant ovarian masses and early- and late-stage cancers.

Postoperative abdominal aspergilloma mimicking cervical cancer recurrence and diagnostic imaging, including F-fluorodeoxyglucose positron emission tomography, with false-positive findings

We present the case of a 39-year-old woman with a subfascial abscess. The patient had undergone radical hysterectomy for stage Ib1 cervical cancer. Six months after the surgery, she was found to have an elevated concentration of the serum squamous cell carcinoma antigen. Thereafter, she underwent magnetic resonance imaging and positron emission tomography-computed tomography. Magnetic resonance imaging revealed an irregular mass (diameter: 2 cm) in the abdominal wall. Increased (18)F-fluorodeoxyglucose uptake into the mass was observed on positron emission tomography. Therefore, we could not rule out the possibility of the peritoneal dissemination of cervical cancer, and we resected the mass. The mass was pathologically and microbiologically diagnosed as a subfascial aspergilloma. The lesion was located in the subfascial area where a drain was inserted at the time of the primary laparotomy.

Prognostic value of postoperative CEA clearance in rectal cancer patients with high preoperative CEA levels

PURPOSE

We determined the prognostic value of carcinoembryonic antigen (CEA) clearance after tumor resection with serial evaluation of postoperative CEA levels in rectal cancer.

METHODS

Between 1994 and 2004, we retrospectively reviewed 122 patients with rectal cancer whose serum CEA levels were measured on the preoperative day and postoperative days 7 and 30. Patients with preoperative CEA levels <5.0 ng/ml were excluded. An exponential trend line was drawn using the three CEA values. Patients were categorized into three groups based on R(2) values calculated through trend line, which indicates the correlation coefficient between exponential graph and measured CEA values: exponential decrease group (group 1: 0.9 < R(2) < or = 1.0), nearly exponential decrease group (group 2: 0.5 < R(2) < or = 0.9), and randomized clearance group (group 3: 0.5 < or = R(2)). We then analyzed the CEA clearance pattern as a prognostic indicator.

RESULTS

With a median follow-up of 57 months, the 5-year overall survival was 62.3% vs. 48.1% vs. 25% and the 5-year disease-free survival was 58.6% vs. 52.7% vs. 25% among groups 1, 2, and 3 (P = 0.014, P = 0.027, respectively) in patients with stage III rectal cancer. For those with stage II rectal cancer, the 5-year overall survival rate of group 1 was significantly better than groups 2 and 3 (88.8% vs. 74.1%, respectively, P = 0.021).

CONCLUSIONS

The postoperative pattern of CEA clearance is a useful prognostic determinant in patients with rectal cancer. Patients with a randomized pattern of CEA clearance after tumor resection should be regarded as having the possibility of a persistent CEA source and may require consideration of intensive follow-up or adjuvant therapy.

Concordant activity of transgene expression cassettes inserted into E1, E3 and E4 cloning sites in the adenovirus genome

BACKGROUND

Expression cassettes can be inserted at several positions into recombinant adenoviral genomes but the implications of this choice for transgene expression level have not been determined. Knowledge of the relative expression levels of transgenes inserted at different sites in the adenoviral genome is of particular significance for transgene expression monitoring approaches that rely on the concordant expression of a marker transgene inserted elsewhere in the viral genome.

METHODS

Three expression cassettes, each comprising a cytomegalovirus promoter driving one of three marker peptides [serum carcinoembryonic antigen (sCEA), beta subunit of human chorionic gonadotropin (betahCG) or human sodium iodide symporter (hNIS)], were inserted into E1, E3 or E4 cloning sites in a recombinant adenoviral vector backbone. High titer stocks of bicistronic adenoviral vectors coding for combinations of marker peptides were prepared. A panel of human cells of various lineages was infected with the vectors and expression ratios of the transgene-encoded proteins were analysed. Serum levels of the soluble proteins and hepatic uptake of radioactive iodine were also compared in vivo in nude rats after intravenous vector infusion.

RESULTS

High concordance of expression between the inserted transgenes was observed in all of the bicistronic vectors irrespective of whether the expression cassettes were placed in the E1, E3 or E4 regions. Concordance was maintained across multiple cell lineages. In vivo, in athymic rats, blood and urine levels of betahCG were highly concordant with serum levels of sCEA at all timepoints after intravenous infusion of the bicistronic vectors encoding both of these soluble markers. Hepatic radioiodine uptake was concordant with serum CEA concentration in mice infused with a bicistronic vector expressing CEA and NIS.

CONCLUSIONS

The expression level of a given transgene in an adenoviral vector genome can be accurately and quantitatively inferred from the expression of a marker protein encoded by a second transgene inserted elsewhere in the vector genome.

Lung Cancer - Clinical Implications

Karcinom pluća je najčešće maligno oboljenje kod muškog pola, a u žena na drugom mestu (nakon raka dojke). Klinička podela na nemikrocelularni (NSCLC) i mikrocelularni (SCLC) odražava različito biološko ponašanje i sledstveno razlike u terapijskom pristupu. Od velike važnosti bi bilo postojanje biomarkera koji bi omogućili razlikovanje ova dva tipa karcinoma pluća, naročito u slučajeva kada nije izvodljiva invazivna dijagnostika kao i u praćenju efekata terapije i ranom otkrivanju relapsa bolesti. Rezultati velikih retrospektivnih ili prospektivnih studija ukazuju na izvesnu vrednost specifičnih markera ili kombinacija ovih markera za dijagnostičke i diferencijalno dijagnostičke svrhe. Merenje četiri serum tumor markera, CYFRA 21-1, CEA, NSE i ProGRP ima opravdanja da bi se identifikovao vodeći marker i na taj način predpostavio verovatni histološki tip tumora. Serijska određivanja odgovarajućeg tumor markera može takođe biti od pomoći da se utvrdi kompletnost uklanjanja tumora i utvrdi relaps bolesti u okultnom kliničkom stadijumu.

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.

A case of serum CEA disappearance curve after resection of breast carcinoma

Carcinoembryonic antigen (CEA) elimination kinetics after tumor resection were measured in a case of breast cancer. A 45-year-old woman with a left breast carcinoma underwent surgery after neoadjuvant chemotherapy. The serum CEA level before surgery was 34.3 ng/ml. After sequential monitoring of serum CEA levels, postoperative serum CEA elimination kinetics were calculated using non-linear least square analysis with the fitting equation C(t)=(C0-Cp)exp(-kt)+Cp, where C(t) was the postoperative CEA level, t was the number days after surgery, C0 was the CEA level at postoperative time zero, Cp was the CEA at plateau, and k was the rate constant of elimination. Cp was calculated as 6.9 ng/ml, which was above the cut-off level and indicated residual malignancy. After adjuvant chemotherapy, CEA normalized to 1.8 ng/ml. In breast cancer patients with high preoperative serum CEA levels, our analytical method for CEA elimination might be useful for the detection of residual malignancies.

Elevation of CA 19-9 in giant hydronephrosis induced by a renal calculus

CA 19-9 is a tumor marker of pancreatic and gastrointestinal cancer. Elevation in nonmalignant disease is rare. The case of a patient with a partial staghorn calculus, giant hydronephrosis, and elevated CA 19-9 serum levels is presented. Open transperitoneal right-sided nephrectomy was performed. In immunohistochemical analysis, CA 19-9 was expressed in the renal tubular epithelium and the renal pelvis. During postoperative follow-up, the CA 19-9 levels returned to normal. Hydronephrosis might cause false-positive results when CA 19-9 measurement is used to screen for malignant disease. Posttreatment CA 19-9 levels of patients with hydronephrosis have to be monitored closely to safely exclude malignant disease.

Time course of carcinoembryonic antigen after resection of lung cancer: a predictor of recurrence

We investigated whether the early postoperative time course of carcinoembryonic antigen (CEA) level after resection of lung cancer could be used to predict patients' prognosis. Fifty-three lung cancer patients were included in this study. Postoperative serum CEA levels were calculated by means of non-linear least-squares fitting to the equation C(t) = (C(0)-C(p))exp(-kt) + C(p), where C(t) is postoperative CEA level, t is days after surgery, C(0) is CEA level at postoperative time 0, C(p) is CEA level at plateau, and k is the rate constant of elimination. Postoperative CEA production (P(p)) was calculated as C(p) multiplied by k. C(p) and P(p) represent the numbers of residual tumor cells after surgery. More residual tumor cells yield higher values of C(p) and P(p), and result in earlier recurrence.

RESULTS

Kinetic parameters could be obtained for 30 patients whose preoperative CEA levels were sufficiently elevated. Cutoff levels as predictors for recurrence were 1.1 ng/ml for C(p) and 0.9 ng/ml/day for P(p). The accuracy of prediction of recurrence using these cutoff levels was 79% with C(p) and 89% with P(p). A very poor prognosis was observed for patients with P(p) over 0.9 ng/ml/day.

CONCLUSION

Analysis of the time course of changes in CEA levels after resection of lung cancer appears to be useful for predicting patient prognosis. C(p) and P(p) are very precise predictors of recurrence.

Non-invasive in vivo monitoring of trackable viruses expressing soluble marker peptides

Noninvasive methods are needed to study the kinetic properties of viruses in living organisms. Oncolytic viruses are used increasingly for cancer therapy but there is currently no satisfactory way to measure efficiency of tumor transduction, changing levels of viral gene expression or the timing of virus elimination. We therefore generated trackable oncolytic measles viruses expressing inert (nonimmunogenic, nonfunctional and accurately measurable) soluble marker peptides. The marker peptides did not compromise virus replication. Ex vivo and in vivo kinetics of the trackable viruses could be easily followed by measuring the concentrations of virally encoded marker peptides in culture supernatant or in serum. When mice bearing human tumor xenografts were challenged with the trackable viruses, distinct kinetic profiles of marker-gene expression could be correlated with distinct therapeutic outcomes. Oncolytic viruses expressing inert soluble marker polypeptides should greatly facilitate the rational development of effective, individually tailored cancer virotherapy.