Prognostic factors of small-cell lung cancer in Okayama Lung Cancer Study Group Trials

The landscape of small cell lung cancer metastases: Organ specificity and timing

BACKGROUND

Early metastasis is a hallmark of small cell lung cancer (SCLC). However, the mechanisms and resulting patterns of SCLC dissemination are unclear. Our aim was thus to investigate the organ specificity and timing of blood-borne metastases in a comprehensive large cohort of SCLC patients.

METHODS

In this retrospective non-interventional cross-sectional study of 1009 Caucasian SCLC patients, we investigated the correlation between the distinct locations of the primary tumor and metastatic sites.

RESULTS

The onset of bone (p < 0.001), brain (p < 0.001), and pericardial (p = 0.02) metastases were late events, whereas adrenal gland (p = 0.005) and liver (p < 0.001) metastases occurred earlier. No significant difference was found in the distribution of early versus late metastases when comparing central and peripheral primary tumors. Patients with bone metastases had a higher than expected likelihood of having liver metastases, while brain metastases tended to appear together with adrenal gland metastases. Pleural and both lung and pericardial metastases also tended to co-metastasize together more frequently than expected if metastatic events occurred independently. Notably, patients with central primary tumors had decreased median overall survival (OS) compared to those with peripheral tumors, although this tendency does not appear to be significant (p = 0.072).

CONCLUSION

Our results are suggestive for particular site- and sequence-specific metastasis patterns in human SCLC. SCLC bone metastases tend to appear together with liver metastases, while brain metastases occur together with adrenal gland metastases. Better understanding of metastasis distribution patterns might help to improve the diagnosis and therapeutic decision-making in SCLC patients.

Gustave Roussy Immune Score and Royal Marsden Hospital Prognostic Score Are Prognostic Markers for Extensive Disease of Small Cell Lung Cancer

Background

The Royal Marsden Hospital prognostic score (RMH score) and the Gustave Roussy immune score (GRIm-score) were developed in order to select more suitable patient for phase I trials. Lactate dehydrogenase (LDH) and serum albumin concentration are common risk factors to these two systems. As the third risk factor, the RMH score and the GRIm-score adopt number of metastatic sites and neutrophil-to-lymphocyte ratio (NLR), respectively. We aimed to investigate whether these two systems are also useful for extensive disease of small cell lung cancer (ED-SCLC).

Methods

We retrospectively collected 128 patients who had initiated platinum-based chemotherapy at our hospital between September 2007 and March 2018. We divided our patients into low (score 0 - 1) and high (2 - 3) score groups, and compared overall survival (OS) and progression-free survival (PFS) between them. Multivariate Cox proportional hazard analyses found prognostic factors of survival times.

Results

Regarding GRIm-score, OS was significantly shorter in high score group than in low score group (median 6.1 vs. 11.4 months, P < 0.01), while no significant difference was observed in PFS (median 4.7 vs. 5.0 months, P = 0.12). Both OS (median 6.9 vs. 12.4 months, P < 0.01) and PFS (median 4.4 vs. 5.4 months, P = 0.01) were significantly shorter in high RMH score group than in low group. Multivariate analyses detected both high GRIm-score (hazard ratio (HR) 1.80, 95% confidence interval (CI) 1.20 - 2.72, P < 0.01) and high RMH score (HR 1.93, 95% CI 1.27 - 2.92, P < 0.01) as independent worse prognostic factors of OS, and then only high RMH score (HR 1.53, 95% CI 1.04 - 2.25, P = 0.03) as independent worse prognostic factor of PFS.

Conclusions

Both RMH score and GRIm-score are useful as independent prognostic factors of OS in ED-SCLC. However, only RMH score is an independent prognostic factor of PFS.

Prognostic value of pretreatment serum lactate dehydrogenase level in patients with solid tumors: a systematic review and meta-analysis

Although most studies have reported that high serum lactate dehydrogenase (LDH) levels are associated with poor prognosis in several malignancies, the consistency and magnitude of the impact of LDH are unclear. We conducted the first comprehensive meta-analysis of the prognostic relevance of LDH in solid tumors. Overall survival (OS) was the primary outcome; progression-free survival (PFS) and disease-free survival (DFS) were secondary outcomes. We identified a total of 68 eligible studies that included 31,857 patients. High LDH was associated with a HR for OS of 1.48 (95% CI = 1.43 to 1.53; P < 0.00001; I² = 93%), an effect observed in all disease subgroups, sites, stages and cutoff of LDH. HRs for PFS and DFS were 1.70 (95% CI = 1.44 to 2.01; P < 0.00001; I² = 13%) and 1.86(95% CI = 1.15 to 3.01; P = 0.01; I² = 88%), respectively. Analysis of LDH as a continuous variable showed poorer OS with increasing LDH (HR 2.11; 95% CI = 1.35 to 3.28). Sensitivity analyses showed there was no association between LDH cutoff and reported HR for OS. High LDH is associated with an adverse prognosis in many solid tumors and its additional prognostic and predictive value for clinical decision-making warrants further investigation.

Specific organ metastases and survival in small cell lung cancer

The aim of our retrospective study was to evaluate the clinicopathological features associated with distant metastasis from small cell lung cancer (SCLC). We reviewed patients diagnosed with SCLC metastasis at the time of presentation between 1999 and 2010. Among the consecutive 251 SCLC patients diagnosed, 152 (60.6%) patients had distant metastasis, of which 20.3, 18.3, 15.5, 10.0 and 6.0% of patients had liver, bone, brain, lung and adrenal gland metastasis, respectively. In a multivariate analysis using Cox's proportional hazards model, we identified that liver, bone and brain metastasis as well as the presence of pleural and/or pericardial fluids were unfavorable prognostic factors. However, lung, adrenal gland and extrathoracic lymph node metastasis were not statistically significant prognostic factors. With regard to the treatment of SCLC patients, particularly those with liver, bone and brain metastasis or pleural and/or pericardial fluids, we should take the metastasizing organs into consideration.

Treatment and outcomes for elderly patients with small cell lung cancer

It is estimated that approximately half of the 500 000 people diagnosed with lung cancer worldwide every year are aged >70 years. Thus, this disease represents a major problem in the elderly and one that will indeed increase as the median age of the population increases. For small cell lung cancer (SCLC), which accounts for approximately 20% of cases of lung cancer, the primary treatment is chemotherapy and in the majority of cases the primary aim is to control the disease which generally would have spread beyond the lungs at the time of presentation. A small number of 'standard' chemotherapy regimens (combined with radiotherapy for patients with limited disease) have been shown to improve survival and quality of life and are widely used. Much of the work investigating the relationship between age and treatment outcomes has been based on clinical trial data and may itself be inherently biased due to trial eligibility criteria excluding elderly patients. However, there is no good evidence that elderly patients fare worse with treatment than their younger counterparts in terms of response rates and survival. Nevertheless with increasing age comes increasing concomitant illnesses which may account for the widely observed increases in drug toxicity, and this may be the primary consideration in selecting the treatment option. Thus for many elderly patients, carboplatin/ etoposide may be the treatment of choice because it is perhaps the least toxic of the standard regimens. Whatever regimen is chosen, the key to treatment effectiveness seems to be to deliver the first 3 or 4 cycles without delay or dosage reduction. Although palliation of symptoms remains a major goal in the treatment of all patients with SCLC there is a dearth of data on whether elderly patients are equally well palliated as their younger counterparts. There is no good evidence that age per se should be a factor in deciding whether patients should receive standard treatment rather than a more gentle approach, and more elderly patients should be included in clinical trials. The key areas where more information is required regarding the treatment and outcomes of elderly patients with SCLC are the assessment of palliation, and comprehensive reviews of all patients diagnosed with the disease, not just those included in trials.