Mutations selected in the hepatitis C virus NS3 protease domain during sequential treatment with boceprevir with and without pegylated interferon alfa-2b.

Treatment with hepatitis C virus (HCV)-NS3-protease inhibitors lead to the selection of resistant variants. Viral kinetics and resistance profiles in patients who are re-treated with the same protease inhibitor are unknown. Viral kinetics and NS3-resistance mutations obtained by clonal sequencing of the NS3-protease were analyzed in nine HCV-genotype-1-infected nonresponder patients who were sequentially treated with boceprevir (400 mg t.i.d.) for 1 week, peginterferon-alfa-2b for 2 weeks and combination of the two for 2 weeks in varying order. In addition to predominant wild-type isolates, previously described boceprevir-resistant mutations (V36, T54, R155, A156, V170) were observed. Furthermore, two resistant mutations (Q41, F43) were detected for the first time in vivo. In three patients, mutations selected after initial treatment with boceprevir were re-selected during subsequent boceprevir exposure. However, mutational patterns after the first and second exposure to boceprevir were different in five patients. In one patient, a viral variant (V55A) known to reduce susceptibility to boceprevir was the predominant variant observed at baseline and throughout treatment and was associated with a shallow viral decline. Different resistance mutations were selected during treatment with boceprevir ± peginterferon. Sequential short-term dosing of boceprevir was not associated with accumulation of resistant variants but pre-existing variants may impair virologic response.

Nonstructural protein 3-4A: the Swiss army knife of hepatitis C virus.

Hepatitis C virus (HCV) nonstructural protein 3-4A (NS3-4A) is a complex composed of NS3 and its cofactor NS4A. It harbours serine protease as well as NTPase/RNA helicase activities and is essential for viral polyprotein processing, RNA replication and virion formation. Specific inhibitors of the NS3-4A protease significantly improve sustained virological response rates in patients with chronic hepatitis C when combined with pegylated interferon-α and ribavirin. The NS3-4A protease can also target selected cellular proteins, thereby blocking innate immune pathways and modulating growth factor signalling. Hence, NS3-4A is not only an essential component of the viral replication complex and prime target for antiviral intervention but also a key player in the persistence and pathogenesis of HCV. This review provides a concise update on the biochemical and structural aspects of NS3-4A, its role in the pathogenesis of chronic hepatitis C and the clinical development of NS3-4A protease inhibitors.

Review article: specifically targeted anti-viral therapy for hepatitis C - a new era in therapy.

BACKGROUND: Novel, directly acting anti-viral agents, also named 'specifically targeted anti-viral therapy for hepatitis C' (STAT-C) compounds, are currently under development. AIM: To review the potential of STAT-C agents which are currently under clinical development, with a focus on agents that target HCV proteins. METHODS: Studies evaluating STAT-C compounds were identified by systematic literature search using PubMed as well as databases of abstracts presented in English at recent liver and gastroenterology congresses. RESULTS: Numerous directly-acting anti-viral agents are currently under clinical phase I-III evaluation. Final results of phase II clinical trials evaluating the most advanced compounds telaprevir and boceprevir indicate that the addition of these NS3/4A protease inhibitors to pegylated interferon-alfa and ribavirin strongly improves the chance to achieve a SVR in treatment-naive HCV genotype 1 patient as well as in prior nonresponders and relapsers to standard therapy. Monotherapy with directly acting anti-virals is not suitable. NS5B polymerase inhibitors in general have a lower anti-viral efficacy than protease inhibitors. CONCLUSIONS: STAT-C compounds in addition to pegylated interferon-alfa and ribavirin can improve SVR rates at least in HCV genotype 1 patients. Future research needs to evaluate whether a SVR can be achieved by combination therapies of STAT-C compounds in interferon-free regimens.

Primary actinomycosis of the liver mimicking malignancy.

A 71-year old women presented with fever, a significant loss of body weight and abdominal pain in the upper right quadrant since approximately six months. Abdominal ultrasonography and magnetic resonance imaging (MRI) showed an irregularly shaped, inhomogeneous and hypointense lesion of the right liver lobe (6 x 8 cm in segment 7 and 8) with multiple satellite lesions. Irregular shape, hypovascular presentation during gadolinium enhancement, hypointensity in T 1-weighted images and dilation of peripheral bile ducts were suggestive for cholangiocarcinoma or metastasis. However, histological investigations revealed a rare case of primary actinomycosis of the liver which was successfully treated with antibiotics.

Gas chromatography/mass spectrometric identification of dopaminergic metabolites in striata of rats treated with L-DOPA.

The ex vivo identification of dopaminergic metabolites present in rat striata after (L-DOPA + benserazide) treatment is reported. The different metabolites have been identified as the trimethylsilyl derivatives in the striatal extracts by gas chromatography/mass spectrometry.

Mass spectral fingerprints of detergents in gasolines using electrospray ionization.

Mass spectral fingerprints of detergents in Austrian, Hungarian, Uruguayan, and Chilean gasolines have been obtained using electrospray ionization mass spectrometry. Polymers or copolymers were observed based on ether motifs (inter-peak spacings of 44, 58 and 72 u) in all samples. Austrian gasoline was found to also contain polymers based on isobutene-amine.

The role of putative intragenic control elements in c-fos regulation by calcium and growth factor signalling pathways.

Sequences in the transcribed region of the c-fos gene have been suggested to control c-fos induction following exposure of cells to mitogens or stimuli that increase intracellular calcium concentrations. Using a mutational analysis we show that putative regulatory elements present in the first intron of the human c-fos gene and the fos-intragenic-regulatory-element (FIRE) are not required for c-fos regulation by growth factor and calcium signalling pathways in AtT20 and PC12 cells. Removal of the c-fos first intron and the FIRE did not increase the basal level of c-fos mRNA and only moderately reduced the magnitude of calcium-induced transcription mediated by either the entire c-fos promoter or the cAMP response element (CRE). Intragenic mutations did not affect serum response element (SRE)-dependent gene expression induced by calcium signals but caused a superinduction of c-fos expression in nerve growth factor-stimulated PC12 cells. These results indicate that c-fos promoter elements, rather than intragenic sequences, are the principal targets of transcription-regulating signalling pathways. This suggests that CRE- and SRE-bound activators of transcription initiation may also enhance, in a signal-dependent manner, c-fos transcript elongation beyond promoter-proximal pause sites.

Detectable blood alcohol after a motor vehicle crash and screening for alcohol abuse/dependence.

OBJECTIVE: To determine the percentage of patients hospitalized after an alcohol-related motor vehicle crash (MVC) who underwent a screening evaluation for alcohol abuse/dependence and had a diagnosis of alcohol abuse/dependence. PATIENTS AND METHODS: Medical and emergency trauma records were reviewed retrospectively for 1994 through 1996 to identify patients who were hospitalized as a result of being involved in an MVC with any detected blood alcohol at the time of admission to a large midwestern Level I trauma center. The primary outcome measure was the performance of alcohol abuse/dependence screening by a psychiatrist or a chemical dependency counselor. A univariate analysis was performed to identify factors associated with the performance of alcohol abuse/dependence screening. The Fisher exact test and the 2-sample rank sum test were used in the analyses. RESULTS: Of the 294 study patients, 78 (26.5%) underwent a screening evaluation for alcohol abuse/dependence by a psychiatrist or a chemical dependency counselor during hospitalization, and 69 (88%) of the 78 patients screened had a diagnosis of alcohol abuse/dependence. Factors associated with the performance of alcohol abuse/dependence evaluation included a known prior history of alcohol abuse, suspicion of alcohol consumption documented by emergency department personnel, higher blood alcohol level at admission, and longer length of hospitalization (all P < .001). CONCLUSION: While the high rate of alcohol abuse/dependence may be explained partially by distinguishing factors in those screened, these findings suggest that routine alcohol abuse/dependence screening of persons presenting with a detectable blood alcohol level following an MVC may identify patients who would benefit from a chemical dependency intervention.

Frequency of noncontiguous lymph node involvement in patients with resectable nonsmall cell lung carcinoma.

BACKGROUND: This study was undertaken to investigate the patterns of lymph node spread and the frequency of involvement of noncontiguous lymph node stations in patients with nonsmall cell lung carcinoma who had complete surgical resection. METHODS: All patients who had surgical resection as their sole treatment for nonsmall cell lung carcinoma during the years 1987-1990 were reviewed. All patients were treated similarly. Generally, complete mediastinal lymph node dissection was performed after resection of the primary lesion and N1 lymph nodes. Patients were assessed for patterns of involvement of N1 and N2 lymph node stations. The frequency of noncontiguous involvement of lymph nodes (involvement of N2 lymph nodes without involvement of N1 lymph nodes) was determined. Patient and tumor characteristics were assessed to ascertain whether certain factors were likely to predict this noncontiguous pattern of lymph node spread. RESULTS: During the 4-year period of study, 336 patients with nonsmall cell lung carcinoma were managed with surgical resection alone. Of the 336, 100 had no involvement of lymph nodes, 108 had involvement of N1 lymph nodes only, 76 had involvement of N1 and N2 lymph nodes, and 52 had involvement of N2 lymph nodes only. Therefore, 52 of all 336 patients (15%) and 52 of 236 patients with lymph node involvement (22%) had noncontiguous lymph node spread. A review of the initial patient and tumor characteristics revealed that patients with a suggestion of enlarged mediastinal lymph nodes on preoperative computed tomography scans of the chest (compared with negative findings) and patients with T1 and T2 lesions (compared with T3 and T4) were more likely to have noncontiguous lymph node spread; the odds ratios (with 95% confidence intervals) were 2.18 (1.01-4.71) and 2.82 (1.36-5.84), respectively. CONCLUSIONS: Noncontiguous involvement of thoracic lymph nodes occurred in approximately 15% of patients who had complete surgical resection of nonsmall cell lung carcinoma. This factor suggests that lack of involvement of N1 lymph nodes does not rule out mediastinal involvement and provides important information for complete surgical staging.

Factors predicting patterns of recurrence after resection of N1 non-small cell lung carcinoma.

BACKGROUND: Although irradiation and chemotherapy are unproved adjuvant treatments for completely resected N1 non-small cell lung carcinoma, previous studies may have been diluted by the inclusion of low-risk patients. Risk factors in this situation, however, are not yet well defined. METHODS: One hundred seven consecutive patients with complete resection of N1 disease who received no other therapy were studied to identify factors independently predicting the risk of freedom from local recurrence (FFLR), freedom from distant metastasis (FFDM), and overall survival (OS). RESULTS: Twelve factors were assessed for a potential prognostic relationship with FFLR, FFDM, and OS. Regression analyses revealed that the factors independently associated with an improved outcome were positive bronchoscopic findings (FFLR, p = 0.005), a greater number of dissected N1 nodes (FFDM, p = 0.02), and a lesser T stage (OS, p = 0.01). Classification and regression tree analyses were then used to separate the patients into risk groups. CONCLUSIONS: Although these results require corroboration in further studies, they may aid the design of trials examining therapies used to decrease rates of local recurrence or distant metastasis.

Patients with stage I non-small cell lung carcinoma at postoperative risk for local recurrence, distant metastasis, and death: implications related to the design of clinical trials.

PURPOSE: Patients with pathologically staged American Joint Committee on Cancer stage I (T1 N0 or T2 N0) non-small cell lung cancer have a favorable prognosis after complete surgical resection compared with patients with more advanced stages. Benefits of adjuvant therapy in this setting are unproved. However, there may be subgroups of patients with stage I disease at high enough risk for local recurrence to prompt consideration of adjuvant or neoadjuvant radiation therapy. Likewise, there may be subgroups of patients at high enough risk for distant metastasis to justify the evaluation of chemotherapy. METHODS AND MATERIALS: From 1987 through 1990, 370 patients undergoing gross total resection of non-small cell lung cancer had stage I disease and received no chemotherapy or radiation therapy as part of their primary treatment. These patients were the subject of a retrospective review to separate patients into high-, intermediate-, and low-risk groups with respect to freedom from local recurrence (FFLR), freedom from distant metastasis (FFDM), and overall survival by using a regression tree analysis. RESULTS: The 5-year rates of FFLR, FFDM, and survival were 85%, 83%, and 66%, respectively. Regression analyses revealed that the factors independently predicting for a poorer FFLR rate included fewer than 15 lymph nodes dissected and pathologically evaluated (p = 0.002) and the presence of a T2 tumor (p = 0.04). Factors independently predicting for a poorer FFDM rate included a maximal dimension greater than 5 cm (p = 0.02) and nonsquamous histology (p = 0.03). Factors independently predicting for a poorer survival rate included fewer than 15 lymph nodes dissected and pathologically evaluated p = 0.001) and a maximal dimension greater than 3 cm (p = 0.003). Regression tree analyses were used to separate patients into risk groups. CONCLUSION: Incorporating the aforementioned factors into regression tree analyses, three risk groups were identified with respect to FFLR. Two each were identified for FFDM and for survival. For each of these three end-points, the differences in outcomes for each risk group were found to be both statistically and clinically significant. These risk groups may be useful in the future design of phase III trials evaluating the use of adjuvant chemotherapy and radiation therapy in the stage I setting.

Patterns of failure and overall survival in patients with completely resected T3 N0 M0 non-small cell lung cancer.

BACKGROUND: Previous studies of patients with surgically resected non-small cell lung cancer and chest wall invasion have shown conflicting results with respect to prognosis. Whether high-risk subsets of the T3 N0 M0 population exist with respect to patterns of failure and overall survival has been difficult to ascertain, owing to small numbers of patients in most series. METHODS AND MATERIALS: A retrospective review was performed to determine patterns of failure and overall survival for patients with completely resected T3 N0 M0 non-small cell lung cancer. From 1979 to 1993, 92 evaluable patients underwent complete resection for T3 N0 M0 non-small cell lung cancer. The following potential prognostic factors were recorded from the history: tumor size, location, grade, histology, patient age, use of adjuvant radiation therapy (18 of 92 patients), and type of surgical procedure (chest wall or extrapleural resection). RESULTS: The actuarial 2- and 4-year overall survival rates for the entire cohort were 48% and 35%, respectively. The actuarial local control at 4 years was 94%. Neither the type of surgical procedure performed nor the addition of thoracic radiation therapy impacted local control or overall survival. CONCLUSION: Patients with completely resected T3 N0 M0 non-small cell lung cancer have similar local control and overall survival irrespective of primary location, type of surgery performed, or use of adjuvant radiation therapy. Additionally, the tumor recurrence rate and overall survival found in this study support the placement of this group of patients in Stage IIB of the 1997 AJCC lung staging classification.

Probable alcohol abuse or dependence: a risk factor for intensive-care readmission in patients undergoing elective vascular and thoracic surgical procedures. Mayo Perioperative Outcomes Group.

OBJECTIVE: To determine whether alcohol abuse or dependence is a risk factor for perioperative complications, increased duration of hospital stay, and increased utilization of nursing resources in patients undergoing thoracic and vascular surgical procedures. MATERIAL AND METHODS: We conducted a prospective study of all adult patients who underwent an elective vascular or thoracic surgical procedure and who received postoperative care in an intensive-care setting. Patients were screened for alcohol abuse or dependence, and actual versus expected durations of stay were evaluated. The patients' medical records were reviewed for preoperative comorbidities and perioperative complications. Fisher's exact test and the rank sum test were used in the analyses. RESULTS: Of 321 study subjects, 290 were classified as nonalcoholic and 31 as probable alcoholic patients. Patients in the probable alcohol abuse group had a significantly increased rate of alcohol withdrawal (12.9% versus 1.7%; P = 0.006) in comparison with patients in the nonalcoholic group. Patients in the probable alcohol abuse group were readmitted to an intensive-care unit more frequently (19.4% versus 7.9%; P = 0.047) and required sedation more often (32.3% versus 13.5%; P = 0.014) than those in the nonalcoholic group. No significant differences were found between the two study groups in intensive-care unit and hospital durations of stay or in utilization of nursing resources. A dismissal diagnosis of alcoholism was recorded for only one of four patients who had a documented withdrawal episode among those categorized in the probable alcoholic group and for three of five patients with alcohol withdrawal symptoms categorized in the nonalcoholic group. CONCLUSION: Except for the occurrence of alcohol withdrawal syndrome, study patients classified in the probable alcohol abuse group did not have more medical or surgical perioperative complications than patients in the nonalcoholic group. They did have significantly more intensive-care setting readmissions. Patients with documented alcohol withdrawal episodes frequently were dismissed without a diagnosis of substance abuse or dependence.

Predictors of subclinical nodal involvement in clinical stages I and II non-small cell lung cancer: implications in the inoperable and three-dimensional dose-escalation settings.

PURPOSE: When mediastinal lymph nodes are clinically uninvolved in the setting of inoperable non-small cell lung cancer, whether conventional radiation techniques or three-dimensional dose-escalation techniques are used, the benefit of elective nodal irradiation is unclear. Inclusion of the clinically negative mediastinum in the radiation portals increases the risk of lung toxicity and limits the ability to escalate dose. This analysis represents an attempt to use clinical characteristics to estimate the risk of subclinical nodal involvement, which may help determine which patients are most likely to benefit from elective nodal irradiation. METHODS: From 1987 to 1990, 346 patients undergoing complete resection of non-small cell lung cancer underwent a preoperative computed tomographic scan revealing no clinical evidence of N2/N3 involvement. Multivariate regression and regression tree analyses attempted to define which patients were at highest risk for subclinical mediastinal involvement (N2) and which patients were at highest risk for subclinical N1 and/or N2 involvement (N1/N2). Immunohistochemical data suggest that the conventional histopathologic techniques used during this study somewhat underestimate the true degree of lymph node involvement; therefore, a third end point was also evaluated: N1 involvement and/or N2 involvement and/or local-regional recurrence (N1/N2/LRR). RESULTS: Regression analyses revealed that the following factors were independently associated with a high risk of more advanced disease: positive preoperative bronchoscopy (N2, p = 0.02; N1/N2, p < 0.0001; N1/N2/LRR, p < 0.001) and tumor grade 3/4 (N1/N2/LRR, p < 0.01). A regression tree analysis was then used to separate patients into risk groups with respect to N1/N2/LRR. CONCLUSION: In inoperable non-small cell lung cancer, the patients for whom mediastinal radiation therapy may most likely be indicated are those with a positive preoperative bronchoscopy, especially with large (> 3 cm) primary tumors.

Bronchial carcinoid tumors: importance of prognostic factors that influence patterns of recurrence and overall survival.

PURPOSE: To analyze bronchial carcinoid characteristics that might influence patterns of disease recurrence and overall survival in patients with these tumors. MATERIALS AND METHODS: In a retrospective review, the actuarial rates of local relapse, regional relapse, and overall survival were determined in patients who had undergone resection of bronchial carcinoid tumors. The evaluable files for 87 patients (50 male, 37 female; age range, 15-82 years) who underwent resection of bronchial carcinoid cancer at the authors' institution between 1980 and 1993 were reviewed for pathologic findings, extent of disease, and recurrence patterns after surgery. RESULTS: The actuarial 4-year overall survival, local control, and regional control rates in the entire cohort of patients were 89%, 92%, and 94%, respectively. Univariate analyses revealed that an atypical histologic pattern was the only tumor-related factor that substantially affected local and regional control. Atypical histologic pattern and tumor size were among the multiple factors that independently affected overall survival. CONCLUSION: Atypical histologic findings in patients who had undergone complete resection of bronchial carcinoid tumors were associated with increased local-regional disease recurrence and decreased survival compared with recurrence and survival in patients with typical histologic findings.

Effectiveness of postoperative irradiation in stage IIIA non-small cell lung cancer according to regression tree analyses of recurrence risks.

BACKGROUND: In the setting of grossly resected stage IIIA (N2 involvement) non-small cell lung carcinoma, the role of adjuvant postoperative thoracic radiation therapy (TRT) remains controversial. This study was initiated to subcategorize these patients into high-, intermediate-, and low-risk groups with respect to local recurrence and survival rates, and to determine whether there were certain subgroups of patients who were particularly likely or unlikely to benefit from postoperative TRT. METHODS: Two hundred twenty-four patients were studied. A regression tree analysis was used to separate patients who had undergone operation alone into groups that had a high, intermediate, or low risk of local recurrence and death. The effect of adjuvant postoperative TRT then was examined in each of these groups. RESULTS: The use of adjuvant postoperative TRT (compared with operation alone) was associated with an improvement in freedom from local recurrence and survival for patients who had an intermediate or high risk of local recurrence and death. However, the greatest level of improvement in freedom from local recurrence (p < 0.0001) and survival (p = 0.0002) associated with the use of adjuvant postoperative TRT was in the high-risk group. Similarly, but of lesser magnitude, the intermediate-risk group had improved freedom from local recurrence and survival rates with the use of adjuvant post-operative TRT (p = 0.002 and p = 0.01, respectively). For the low-risk group, the freedom from local recurrence and survival rates were not statistically different between the patients who received adjuvant postoperative TRT and those who underwent observation. CONCLUSIONS: Patients with non-small cell lung carcinoma involving ipsilateral mediastinal lymph nodes (stage IIIA) who undergo gross resection and who are at either high or intermediate risk for local recurrence and death are likely to benefit from adjuvant postoperative irradiation. The role of radiation therapy in low-risk patients is unclear. Prospective confirmation of these observations is warranted.

The impact of surgical adjuvant thoracic radiation therapy for patients with nonsmall cell lung carcinoma with ipsilateral mediastinal lymph node involvement.

BACKGROUND: Previous nonsmall cell lung carcinoma studies have shown that patients with ipsilateral mediastinal (N2) lymph node involvement who underwent surgical resection have a greater local recurrence rate than those with less lymph node involvement (N0, N1). Therefore, it was hypothesized that complete surgical clearance of subclinical lymph node disease is difficult in N2 patients and that adjuvant postoperative thoracic radiotherapy (TRT) may be beneficial. METHODS: A retrospective review was performed to determine the local recurrence and survival rates for patients with N2 disease undergoing complete surgical resection with or without adjuvant TRT. Between 1987 and 1993 at the Mayo Clinic, 224 patients underwent complete resection of N2 nonsmall cell lung carcinoma. More than one mediastinal lymph node station was sampled in 98% of patients; 39% then received adjuvant TRT (median dose, 50.4 grays). RESULTS: The median follow-up time was 3.5 years for the patients who were alive at the time of the analysis. The surgery alone versus surgery plus TRT groups were well balanced with respect to gender, age, histology, tumor grade, number of mediastinal lymph node stations dissected or involved, and involved N1 lymph node number. There were slightly more patients with right lower lobe lesions (compared with other lobes), patients with multiple lobe involvement, and patients with only one N2 lymph node involved in the surgery alone group. After treatment with surgery alone, the actuarial 4-year local recurrence rate was 60%, compared with 17% for treatment with adjuvant TRT (P < 0.0001). The actuarial 4-year survival rate was 22% for treatment with surgery alone, compared with 43% for treatment with adjuvant TRT (P = 0.005). On multivariate analysis, the addition of TRT (P = 0.0001), absence of superior mediastinal lymph node involvement (P = 0.005), and fewer N1 lymph nodes involved (P = 0.02) were independently associated with improved survival rate. CONCLUSIONS: This study, which to the authors' knowledge is the largest evaluating adjuvant TRT in N2 nonsmall cell lung carcinoma, suggests that adjuvant TRT may improve local control and survival.