Accuracy of the non-sentinel node risk score (N-SNORE) in patients with cutaneous melanoma and positive sentinel lymph nodes: a retrospective study

BACKGROUND

Sentinel node (SLN) biopsy in patients with melanoma permits identification of those at risk for further metastases in non-sentinel lymph nodes (NSLN). However, a mere 20% of SLN-positive patients have metastases in NSLN. Therefore we need criteria to predict NSLN-positivity. A new score system known as the non-sentinel risk score, (N-SNORE) based on five clinical and pathological characteristics (gender, regression in primary melanoma, proportion of SNs containing melanoma, perinodal lymphatic invasion, and SN tumor burden), was first published in 2010. In this study, the accuracy of N-SNORE was validated in melanoma patients with positive SLN.

METHODS

A total of 106 melanoma patients with positive SLN, who had undergone complete lymph node dissection (CLND) subsequently, were included in the study. The N-SNORE was calculated in all patients, and the risk was compared to the frequency of NSLN metastases. Statistical analysis of the data was performed.

RESULTS

Thirteen patients were at very low risk for NSN metastasis (score 0), 63 patients at low risk (score 1-3), 19 at intermediate risk (score 4-5), 6 at high risk (score 6-7), and 5 at very high risk (score >8). NSLN positivity rates for these 5 risk groups were 7.7%, 18.2%, 21.1%, 33.3%, and 80%, respectively. According to Fisher's exact test, the contingency coefficient was .322; the p-value was .025.

CONCLUSION

An increasing N-SNORE was clearly correlated with a higher risk of NSLN positivity. Based on the p-value and the contingency coefficient, the overall accuracy of the N-SNORE was proven on statistical calculation.

EGFR and HER2 inhibition in pancreatic cancer

The aim of this study was to investigate the effect of lapatinib, a selective inhibitor of EGFR/HER2 tyrosine kinases, on pancreatic cancer cell lines both alone and in combination with chemotherapy. Two cell lines, BxPc-3 and HPAC, displayed the greatest sensitivity to lapatinib (IC(50)<2 μM). Lapatinib also demonstrated some activity in three K-Ras mutated pancreatic cancer cell lines which displayed resistance to erlotinib. Drug effect/combination index (CI) isobologram analysis was used to study the interactions of lapatinib with gemcitabine, cisplatin and 5'deoxy-5'fluorouridine. Concentration-dependent anti-proliferative effects of lapatinib in combination with chemotherapy were observed. To evaluate the potential effect of lapatinib in pancreatic cancer tumours, and to identify a subset of patient most likely to benefit from lapatinib, expression of EGFR and HER2 were investigated in 72 pancreatic cancer tumour specimens by immunohistochemistry. HER2 membrane expression was observed in only 1 % of cases, whereas 44 % of pancreatic tumours expressed EGFR. Based on our in vitro results, lapatinib may provide clinical benefit in EGFR positive pancreatic ductal adenocarcinoma.