Elevation in serum uric acid levels predicts favourable response to erlotinib treatment in patients with metastatic non-small-cell lung cancer

WHAT IS KNOWN AND OBJECTIVE

Erlotinib is a small molecule tyrosine kinase inhibitor which blocks the activation of epidermal growth factor receptor (EGFR), a transmembrane receptor that is upregulated in many cancer types. Inhibition of angiogenesis with consequent impairments in intratumoral microcirculation is one of the mechanisms through which EGFR inhibition halts the progression of cancer. A consequence of impaired microcirculation is intratumoral hypoxia, which results in increases in serum uric acid levels. The goal of this study was to investigate the relationship between serum uric acid levels and response to erlotinib in metastatic non-small-cell lung cancer (NSCLC).

METHODS

A total of 56 patients with metastatic non-small-cell lung cancer who received erlotinib for a duration of at least 3 months were included in this retrospective cohort study. Demographic characteristics, progression status, baseline serum uric levels and 3-month serum uric acid levels were recorded and analysed.

RESULTS AND DISCUSSION

Of the study population, 21 (37.5%) were female and 35 (62.5%) were male patients. No significant difference in above demographic characteristics was observed among exitus, survivor with progression and survivor without progression groups. Patients who responded favourably to erlotinib with no progression of their disease had significantly increased uric acid levels at 3-month follow-up (P = .01). Such a correlation was not observed if the patient was exitus (P = .47) or had progressed on erlotinib therapy (P = .19).

WHAT IS NEW AND CONCLUSION

In conclusion, this study is the first to demonstrate significant increases in serum uric acid levels in patients with metastatic NSCLC who responded favourably to erlotinib and had no progression under erlotinib therapy. Further studies are required to confirm and characterize serum uric acid as a novel biomarker in predicting the outcome in those with metastatic NSCLC.

Level of pleural invasion effects on prognosis in lung cancer

Objective:

To analyze the extent of visceral pleural invasion (VPI) and its effect on survival along with its place in determining the T descriptor in TNM staging in our patients.

Methods:

A total of 233 patients underwent lung resection. The data were retrospectively analyzed in terms of sex, age, histopathologic type, stage of the tumor, extent of VPI, and survival. Patients who had neoadjuvant chemotherapy or chemoradiotherapy, distant metastasis, parietal pleural invasion, and operative mortality were excluded.

Results:

The median follow-up was 59 months (range 4–126). The extent of VPI was PL0 in 119 (65.7%) patients, PL1 in 47 (26%) patients, and PL2 in 15 (8%) patients. The median survival rates were 65 (range 43–96) months for PL0, 54 (range 37–72) months for PL1, and 39 (range 12–69) months for PL2. The 5-year overall survival rates were 74.7% for PL0, 77.8% for PL1, and 53.3% for PL2. There were statistically significant differences in overall survival among PL0, PL1, and PL2 ( p = 0.03). In subgroup analysis, the difference was insignificant in PL0 vs PL1 ( p = 0.81), but significant in PL0 vs PL2 ( p = 0.02) and PL1 vs PL2 ( p = 0.04) groups.

Conclusions:

This study emphasizes that the presence of VPI is related with poor prognosis independent of lymph node positivity, histologic subtypes, and tumor size. As the study shows, PL0 and PL1 have similar survival rates and these two groups may be considered as VPI (−) patients whereas PL2 disease affects survival outcomes.