Surgical resection for lung cancer in the octogenarian

BACKGROUND: As the US population ages, clinicians are increasingly confronted with octogenarians with resectable non-small cell lung cancer. Earlier reports documented substantial risk for surgical resection in this age group. METHODS: We reviewed our surgical experience in octogenarians who underwent curative resection from 1990 to 2003. RESULTS: Sixty-one patients underwent resection: 46 lobectomies, 6 segmentectomies, 5 wedge resections, and 4 pneumonectomies. There was one perioperative death (1.6%). The overall complication rate was 38% with a major complication rate of 13%. The average postoperative length of stay was 7 days. Overall 5-year survival was 38%, and 82% for stage IA patients. Patients with more advanced disease had a significantly worse survival. CONCLUSIONS: Appropriately selected octogenarians with early stage disease should be offered anatomic surgical resection for cure. These patients can anticipate a long-term survival, and should not be denied an operation on the basis of age alone.     

PAX-5 expression in pulmonary neuroendocrine neoplasms: its usefulness in surgical and fine-needle aspiration biopsy specimens

The World Health Organization classification of lung tumors recognizes 4 histologic subtypes of pulmonary neuroendocrine carcinomas (NECs), which include typical carcinoids (TCs), atypical carcinoids (ACs), small cell carcinomas (SCCs), and large cell NECs (LCNECs). These tumors can be misclassified owing to morphologic parallels, indicating the necessity for adjunctive tests for correct classification. We evaluated immunohistochemical expression of PAX-5 in histologic and fine-needle aspiration (FNA) specimens of pulmonary NECs. Staining was stratified by intensity (0 to 3+) and percentage of cells stained as focal (<10%) or diffuse (=10%). PAX-5 expression was present in 29/37 (78%) of high-grade NECs (22/26 SCCs, 1/2 LCNECs, and 6/9 combined tumors) and none of 51 TCs and ACs; FNA specimens showed concordant staining. This study confirmed that PAX-5 is a useful marker in FNA and surgical specimens for the discrimination of low- to intermediate-grade NECs from high-grade NECs with 100% specificity and 79% sensitivity in surgical specimens.     

PLASMID MEDIATED DRUG RESISTANCE IN VIBRIO CHOLERAE 0139 BENGAL

Sixteen strains of Vibrio cholerae were isolated from cases of diarrhoea. Out of these, 12 (75%) were identified as Vibrio cholerae 0139 synonym Bengal and 4 (25%) as Vibrio cholerae El Tor by standard biochemical and serological tests. Modified CAMP reaction in sheep blood agar showed that 0139 produced moderate hemolysis, El Tor produced wider zone of hemolysis whereas Classical Vibrio cholerae produced no zone of hemolysis (CAMP negative). Break point minimum inhibitory concentration (MIC) by agar dilution method showed that all 0139 strains were resistant to ampicillin 8 mg/L, streptomycin 1 mg/L, chloramphenicol 8 mg/L, sulphamethoxazole 32 mg/L and trimethoprim 0.3-128 mg/L, 58.3% were sensitive to gentamicin 1 mg/L, and all were sensitive to norfloxacin 1 mg/L and cefotaxime 1 mg/L. Resistance to trimethoprim, sulphamethoxazole, ampicillin and gentamicin in 5 strains could be transferred to E coli K-12 by conjugation experiment at a rate of 5×10⁻⁶ to 4×10⁻³. Distinct plasmid bands of 35.8 mega daltons could be seen in agarose gel electrophoresis.KEY WORDS: CAMP test, Drug resistance, Plasmid, Vibrio cholerae 0139.     

Long-term outcome after resection for bronchial carcinoid tumors.

OBJECTIVES: We sought to determine the long-term survival of patients treated for bronchial carcinoid tumors and whether lesser resections have had an effect on outcomes. METHODS: We conducted a retrospective, multi-institutional review of patients treated surgically for primary bronchial carcinoid tumors since 1980. Operative approach, pathologic stage, histology, surgical complications, tumor recurrence, and long-term survival were assessed. RESULTS: There were 50 men and 89 women with a mean age of 52.2+/-17.4 and 58.9+/-13.3 years, respectively (P=0.021). Men were more likely to be current or former smokers than were women. Operations included lobectomy or bilobectomy in 110, pneumonectomy in four, wedge resection in 22, and bronchial sleeve resection only in three patients; resection was performed thoracoscopically in six patients. One patient died postoperatively. Stages were I, 121; II, nine; III, six; and IV, three. Typical carcinoid tumors were stage I in 100 and more advanced (stages II-IV) in nine, whereas atypical carcinoid tumors were stage I in 18 and more advanced in eight (P=0. 002). Median follow-up was 43 months (range 1-149) during which 21 (15%) patients died (four from recurrent cancer) and 19 patients (14%) were lost to follow-up. Recurrent cancer developed in 2/98 patients with typical and 5/25 patients with atypical subtypes (P<0. 001; log-rank test). The likelihood of recurrence was related to histological subtype (relative risk 7.9 for atypical carcinoid; 95% confidence interval 1.4-43.5). Five-year survival was 88% for stage I patients and was 70% for patients with more advanced stages. When stratified by stage, survival was related to age (relative risk=1.9 for a 10 year increase in age; 95% confidence interval 1.2-2.9) and possibly to the histological subtype, but not to patient gender, year of operation, or type of operation performed. CONCLUSIONS: Either major lung resection or wedge resection is appropriate treatment for patients with early stage typical bronchial carcinoid tumors. Survival is favorable for early stage tumors regardless of histological subtype. Local recurrence is more common among patients with atypical subtypes, suggesting that a formal resection may improve long-term outcome.     

Retrospective Study on Efficacy of Intermaxillary Fixation Screws

Background

We evaluated the efficacy of intermaxillary fixation (IMF) screws in the treatment of mandibular fractures.

Methods

Two hundred patients with mandibular fractures, treated by IMF using these screws, were evaluated by pre and postoperative panoramic radiographs. Clinical testing was carried out for vitality and abnormal mobility of teeth adjacent to the site of screw insertions. Other factors such as possible iatrogenic dental injuries, loss, breakage or screw cover by oral mucosa and postoperative occlusion were also studied.

Result

The most important complication noticed was iatrogenic damage to dental roots.

Conclusion

Use of intraoral cortical bone screws for IMF is a valid alternative to arch bars in the treatment of mandibular fractures. Iatrogenic injury to dental roots is the commonest problem which can be minimized by an experienced surgeon.Key Words: Intermaxillary fixation, Bone screws, Mandibular fractures, Iatrogenic injury     

Frequency and clinicopathologic correlates of KRAS amplification in non-small cell lung carcinoma

Background

Characterization of the non-small cell lung cancer (NSCLC) genome has suggested that KRAS amplification is one of the commonest molecular abnormalities in NSCLC. However, the prevalence and clinicopathologic significance of KRAS amplification, and its relationship with KRAS activating mutations have not been well-defined. The purpose of this study was to establish the prevalence of KRAS amplification in two separate, large NSCLC cohorts, to define the clinicopathologic features of KRAS-amplified NSCLC in a single uniformly treated cohort, and to investigate the interplay between KRAS amplification and KRAS mutation.

Methods

Fluorescence in situ hybridization was utilized to detect KRAS amplification on tissue microarrays constructed from a Swiss cohort of 538 NSCLCs and a series of 402 patients with NSCLC treated in a single institution in New York. DNA sequencing to detect KRAS codon 12 activating mutations was performed on a subset of tumors. Amplification and mutation status were compared with patient baseline characteristics, tumor characteristics, and overall- and disease-free survival.

Results

The prevalence of KRAS amplification was 13.7% in the Swiss cohort and 15.1% in the New York cohort. Among adenocarcinomas, KRAS amplification was associated with larger (mean size 2.8 ± 1.8 cm vs. 2.1 ± 1.3 cm, p = 0.003), less well-differentiated tumors (18% vs. 42%, p = 0.004) that were more likely to be invasive (95% vs. 77%, p = 0.004) and to exhibit angiolymphatic invasion (24% vs. 12%, p = 0.04). These differences were statistically significant within the subset of adenocarcinomas harboring activating KRAS mutations, suggesting a synergistic relationship between amplification and mutation. No significant association between KRAS amplification and nodal metastasis or survival was seen.

Conclusions

KRAS amplification is a common molecular alteration in NSCLC, characterizing ∼15% of tumors. This alteration is associated with indicators of local aggressiveness, and may act synergistically with KRAS mutations to promote tumor progression.