Preoperative serum carbohydrate antigen 19-9 levels predict early recurrence after the resection of early-stage pancreatic ductal adenocarcinoma

BACKGROUND

Pancreatic ductal adenocarcinoma (PDAC) is a serious disease with a poor prognosis. Only a minority of patients undergo surgery due to the advanced stage of the disease, and patients with early-stage disease, who are expected to have a better prognosis, often experience recurrence. Thus, it is important to identify the risk factors for early recurrence and to develop an adequate treatment plan.

AIM

To evaluate the predictive factors associated with the early recurrence of early-stage PDAC.

METHODS

This study enrolled 407 patients with stage I PDAC undergoing upfront surgical resection between January 2000 and April 2016. Early recurrence was defined as a diagnosis of recurrence within 6 mo of surgery. The optimal cutoff values were determined by receiver operating characteristic (ROC) analyses. Univariate and multivariate analyses were performed to identify the risk factors for early recurrence.

RESULTS

Of the 407 patients, 98 patients (24.1%) experienced early disease recurrence: 26 (26.5%) local and 72 (73.5%) distant sites. In total, 253 (62.2%) patients received adjuvant chemotherapy. On ROC curve analysis, the optimal cutoff values for early recurrence were 70 U/mL and 2.85 cm for carbohydrate antigen 19-9 (CA 19-9) levels and tumor size, respectively. Of the 181 patients with CA 19-9 level > 70 U/mL, 59 (32.6%) had early recurrence, compared to 39 (17.4%) of 226 patients with CA 19-9 level ≤ 70 U/mL (P < 0.001). Multivariate analysis revealed that CA 19-9 level > 70 U/mL (P = 0.006), tumor size > 2.85 cm (P = 0.004), poor differentiation (P = 0.008), and non-adjuvant chemotherapy (P = 0.025) were significant risk factors for early recurrence in early-stage PDAC.

CONCLUSION

Elevated CA 19-9 level (cutoff value > 70 U/mL) can be a reliable predictive factor for early recurrence in early-stage PDAC. As adjuvant chemotherapy can prevent early recurrence, it should be recommended for patients susceptible to early recurrence.

Sentinel Lymph Node Biopsy in Patients Who Have Negative Conversion of Axillary Lymph Node after Neoadjuvant Chemotherapy for Node Positive Breast Cancer

Background: Sentinel lymph node biopsy (SLNB) after neoadjuvant chemotherapy (NAC) has been currently debatable. It is possible that the tumor response to chemotherapy may alter the lymphatic drainage thus causing lower SLN identification rate and higher false negative rate. Further, the response of NAC can be different in each lymph nodes. It is doubtful whether SLNB can accurately predict axillary lymph node (ALN) status after NAC. The aim of this study to determine the identification rate, the false-negative rate, and the accuracy of SLNB after NAC for node positive breast cancer.Patients and Methods: A prospective study was initiated to evaluate the results of SLNB after NAC. From January 2007 to April 2009, 81 patients with positive axillary lymph nodes enrolled from two institutions after IRB-approved. They received NAC and then evaluated negative conversion of metastatic lymph node with both PET and breast US. All of them underwent ALN dissection after SLNB with subareolar intradermal injection technique using radioisotope. We evaluated the identification rate, false negative rate, accuracy of SLNB according to the response of chemotherapy in axillary lymph nodes (negative conversion group or remaining positive group).Results: Before the NAC, 31 patients had multiple axillary lymph node metastasis and 50 patients had single metastasis. After NAC 44 cases (54.3%) turned into negative node and 37 cases (45.7%) remained positive nodes. Total identification rate was 80.2% (65 of 81), false negative rate was 19.0% (8 of 42) and accuracy was 87.7% (57 of 65). In negative conversion group showed 84.1% (37 of 44) of identification rate, 21.1% (4 of 19) of false negative rate, 89.2% (33 of 37) of accuracy. In remaining positive group revealed 75.7% (28 of 37) of identification rate, 17.4% (4 of 23) of false negative rate, 85.7% (24/28) of accuracy. There was no statistical significant difference of identification rate, false negative rate, accuracy of SLNB among the two group after NAC (p=0.343, p=0.534, p=0.478, respectively).Conclusion: This study showed relatively low detection rate and accuracy, high false-negative rate of SLNB, even if the positive nodes changed to negative node after NAC. Thus sentinel lymph node biopsy after NAC for node positive breast cancer should be cautious. Since this study had small number of negative conversion patients, further larger prospective studies are required for more proper conclusion.

Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 1022.

Immunobead RT-PCR versus regular RT-PCR amplification of CEA mRNA in peripheral blood

PURPOSE

The reverse transcription polymerase chain reaction (RT-PCR) amplification of tumor-specific mRNA has been used for the detection of cancer cells in peripheral blood. More recently, an immunomagnetic isolation and reverse transcription polymerase chain reaction (immunobead RT-PCR) was developed which has reportedly significant advantages over the previous RT-PCR analysis. In our study, we compared these two methods using a model set of peripheral blood containing tumor cells under standardized conditions.

MATERIAL AND METHODS

In order to compare the false positive rate, normal peripheral blood samples from five volunteers were analyzed by both methods. A model set of peripheral blood containing tumor cells was established by adding SNUC4 human colon cancer cells to peripheral blood collected from normal volunteers not showing any nonspecific bands upon electrophoresis of the PCR products. RT-PCR amplification of carcinoembryonic antigen (CEA) mRNA was done with total RNA and mRNA prepared from this model sample. In immunobead RT-PCR analysis, mRNA was prepared from the cells isolated with anti-CEA antibody-coated magnetic beads or anti-Ber-EP4 antibody-coated magnetic beads before the RT-PCR analysis.

RESULT

The immunobead RT-PCR yielded no non-specific band, while the regular RT-PCR using total RNA did show non-specific band formation in all five samples. When mRNA rather than total RNA was used, nonspecific bands were formed in three of the five samples. Immunobead RT-PCR allowed the detection of 10(1) tumor cells in 1 ml of peripheral blood. The regular RT-PCR analysis had a detection limit of 10(2) tumor cells in 1 ml of peripheral blood.

CONCLUSION

The immunobead RT-PCR proved to be more sensitive and specific than the regular RT-PCR at least in our model system.

The DNA replication-related element (DRE)-DRE-binding factor (DREF) system may be involved in the expression of the Drosophila melanogaster TBP gene

The TATA box binding protein (TBP) is a general transcription factor required for initiation by all three eukaryotic RNA polymerases. Previously, we found that the promoter region of the Drosophila melanogaster TBP gene contains three sequences similar to the DNA replication-related element (DRE) (5'-TATCGATA). In the present study, we found that the DRE-like sequences are also present in the promoter of the Drosophila virilis TBP gene, suggesting a role for these sequences in TBP expression. Band mobility shift assays revealed that oligonucleotides containing sequences similar to the DRE of D. melanogaster TBP gene promoter form specific complexes with a factor in a Kc cell nuclear extract and with recombinant DRE-binding factor (DREF). Furthermore, these complexes were either supershifted or diminished by monoclonal antibodies to DREF. Transient luciferase assays demonstrated that induction of mutations in two DRE-related sequences at positions -223 and -63 resulted in an extensive reduction of promoter activity. Thus, the DRE-DREF system appears to be involved in the expression of the D. melanogaster TBP gene.

Determination of residue specificity in the EF-hand of troponin C for Ca2+ coordination, by genetic engineering

Utilizing protein engineering of troponin C (TnC), combined with the physiology of skinned fibers, the present study sought to delineate the mechanisms for metal ion coordination and sensitivity in the sites (EF-hands) that execute the Ca2+ switch for contraction. A total TnC-encoding gene comprising multiple target sequences for restriction enzymes was synthesized, furnishing a pliant molecular handle to manipulate sites I and II in the NH2 terminus of the protein. Of the six positions (X, Y, Z, -Y, -X, and -Z) essential for metal ion chelation in a typical EF-hand, invariably the X position has aspartate, and -Z position has glutamate. In the X position of site II, mutation of aspartate for either glutamate (gamma-carboxylate) or asparagine (same side chain length as aspartate) yielded functionally inactive proteins with concomitantly diminished Ca2+ binding capacity. Similarly, in -Z position (site I), neither aspartate nor glutamine were compatible in exchange for the conserved glutamate. In contrast, for the Y coordinate of site II, a preference for asparagine comparable to that for wild-type aspartate was detected, but glutamate was impermissible. Evidently, physicochemical and steric factors both are critical in governing the mechanism for metal ion chelation in TnC in a physiological milieu. Furthermore, the findings manifest that the quaternary structure of hydrated TnC restrains the EF-hands during on-off operation of the Ca2+ switch.

[Analytical diagnosis in colposcopy by subdivision of abnormal findings]

Abnormal findings of Colposcopy (Colp) were classified in contrast with histology. Varieties of colposcopic abnormal findings appear in more advanced changes in cervical diseases; single in squamous metaplasia, dysplasia and some Ca in situ, double in Ca in situ and microinvasive Ca, triple microinvasive and advanced carcinoma. Atypical vessels are frequently encountered in invasive carcinoma. Circular extension of abnormal figures around external os indicated the following correlation: Within 1/4-2/4 in dysplasia, 2/4-3/4 in Ca in situ and microinvasive Ca, 3/4-4/4 in microinvasive and invasive Ca. In squamous metaplasia and dysplasia, the white epithelia were flat on the surface, comparatively clear in the white part and less elevated. On the other hand, in carcinoma in situ, corresponding to the pathological area, they were rough on the surface, unclear in the white part and highly elevated. Compared with squamous metaplasia and dysplasia, carcinoma in situ in punctation revealed more surface elevation and unclear white part. Characteristic histological figures are dot types in the metaplasia and dysplasia, nest-like types in the carcinoma in situ and atypical vessel transition types in the microinvasive carcinoma. Complete types of mosaic were observed more in metaplasia, slight dysplasia and carcinoma in situ, while the incomplete types were common in moderate and severe dysplasia. Microinvasive carcinoma mosaic revealed more incomplete types and atypical vessel transition types. As for surface elevation and unclear white part, the same tendency was noticed as in punctation and white epithelium.(ABSTRACT TRUNCATED AT 250 WORDS)