Prophylactic cranial irradiation in lung cancer

Research progress in the treatment of small cell lung cancer

Small cell lung cancer (SCLC) accounts for approximately 10-15% of all lung cancers. No significant improvement has been made for patients with SCLC in the past several decades. The main progresses were the thoracic radiation and prophylactic cranial irradiation (PCI) that improved the patient survival rate. For patients with limited disease and good performance status (PS), concurrent chemoradiotherapy (CCRT) followed by PCI should be considered. For extensive disease, the combination of etoposide and platinum-based chemotherapy remains the standard treatment and consolidative thoracic radiotherapy is beneficial for patients who have a significant respond to initial chemotherapy. However, the prognosis still remains poor. Recently, efforts have been focused on molecular targets and immunotherapy. But numerous molecular targets methods have failed to show a significant clinical benefit in patients with SCLC. It is anticipated that further development of research will depend on the on-going trials for molecular targeted therapy and immunotherapy which are promising and may improve the outcomes for SCLC in the next decade.

The Current Role of Radiotherapy in the Treatment of Small Cell Lung Cancer

Radiotherapy has been shown to play a key role in the management of small cell lung cancer. There are well-established data in the literature for the use of concurrent chemoradiotherapy for stage I-III disease, although key questions remain over the timing of radiation, the optimal dose/fractionation and particularly once versus twice daily treatment, the use of elective nodal irradiation and drug combinations. Data for the use of thoracic radiation in stage IV disease, after chemotherapy, have recently become available and are leading to a change in practice. Prophylactic cranial irradiation has been shown to be of use in both stage I-III and stage IV disease, although uncertainties surround its use in the elderly population and the use of brain imaging before treatment. This overview will address the current available evidence and focus on areas for future research.

Identification of breast cancer patients with a high risk of developing brain metastases: a single-institutional retrospective analysis

Background

The objective of this study was to identify breast cancer patients with a high risk of developing brain metastases who may benefit from pre-emptive medical intervention.

Methods

Medical records of 352 breast cancer patients with local or locoregional disease at diagnosis were retrospectively analysed. The brain metastasis-free survival was estimated using the Kaplan-Meier method and patient groups were compared using the log rank test. The simultaneous relationship of multiple prognostic factors was assessed using Cox’s proportional hazard regression analysis. The Fisher exact test was used to test the difference of proportions for statistical significance.

Results

On univariate analysis, statistically highly significant unfavourable risk factors for the brain metastasis-free survival were negative ER status, negative PR status, and triple negative tumor subtype. Young age at diagnosis (≤35 years) and advanced disease stage were not statistically significant (p = 0.10). On multivariate analysis, the only independent significant factor was the ER status (negative ER status; hazard radio (95% confidence interval), 5.1 (1.8-14.6); p = 0.003). In the subgroup of 168 patients with a minimum follow-up of 24 months, 49 patients developed extracranial metastases as first metastatic event. Of those, 7 of 15 (46.6%) with a negative ER status developed brain metastases compared to 5 of 34 (14.7%) with a positive ER status (Fisher exact test, p = 0.03). The median time interval (minimum-maximum) between the diagnosis of extracranial and brain metastases was 7.5 months (1-30 months).

Conclusions

Breast cancer patients with extracranial metastasis and negative ER status exhibited an almost 50% risk of developing brain metastasis during their course of disease. Future studies are highly desired to evaluate the efficacy of pre-emptive medical intervention such as prophylactic treatment or diagnostic screening for high risk breast cancer patients.

Benefits of postoperative radiotherapy in multimodality treatment of resected small-cell lung cancer with lymph node metastasis

AIM

The purpose of this study is to evaluate the role of postoperative radiotherapy (PORT) in resected small-cell lung cancer (SCLC).

METHODS

This study retrospectively analyzed 143 patients with completely resected SCLC in our institution between 1996 and 2011. The primary endpoint was overall survival (OS). The log-rank test and Cox regression model were used to evaluate the factors influencing local-regional recurrence (LRR) and OS.

RESULTS

The median OS for the entire population was 34 months, and the 5-year OS rate was 34.6%. In multivariate analysis, age, surgical procedure, pathology stage, adjuvant chemotherapy and distant relapse were significant factors for survival. For the whole population, PORT had no effect on OS, with a median OS of 40 months in the PORT group versus 27 months in the non-PORT group (p = 0.260). However, in patients with N1 disease, the median OS were 40 months in the PORT group versus 14 months in the non-PORT group (p = 0.032). The corresponding OS in N2 patients were 35 months versus 17 months, respectively (p = 0.040). Similarly, PORT significantly reduced the LRR in patients with positive lymph node. For patients with N1 disease, the 3-year LRR rate was 0.0% in the PORT group versus 14.3% in the non-PORT group (p = 0.037). The corresponding LLR rate in N2 patients was 4.2% versus 56.6% (p < 0.001).

CONCLUSION

PORT significantly reduced LRR and improved OS in patients with regional metastasis SCLC. We suggest supplementing PORT in the multimodality treatment of resected SCLC with lymph node metastasis.

Neurologic complications of lung cancer

Neurologic complications of lung cancer are a frequent cause of morbidity and mortality. Tumor metastasis to the brain parenchyma is the single most common neurologic complication of lung cancer, of any histologic subtype. The goal of radiation therapy and in some cases surgical resection for patients with brain metastases is to improve or maintain neurologic function, and to achieve local control of the brain lesion(s). Metastasis of lung cancer to the spinal epidural space requires urgent evaluation and treatment. Early diagnosis and modern surgical and radiotherapy techniques improve neurologic outcome for most patients. Leptomeningeal metastasis is a less common but ominous occurrence in patients with lung cancer. Lung carcinomas can also occasionally metastasize to the brachial plexus, skull base, dura, or pituitary. Paraneoplastic neurologic disorders are uncommon but important complications of lung carcinoma, and are generally the presenting feature of the tumor. Paraneoplastic disorders are believed to be caused by an autoimmune humoral or cellular attack against shared "onconeural" antigens. The most frequent paraneoplastic disorders in patients with lung cancer are Lambert-Eaton myasthenic syndrome, and multifocal paraneoplastic encephalomyelitis, both mainly occurring in association with small-cell lung carcinoma. There is a variety of other paraneoplastic disorders affecting the central and peripheral nervous systems. Some affected patients have a good neurologic outcome, while others are left with severe permanent neurologic disability.

Brain metastasis as an isolated late recurrence in small-cell lung cancer

The brain is one of the most common sites of metastasis of small-cell lung cancer (SCLC). In this study, we reported 6 cases with isolated brain relapse of SCLC ≥1 year after the completion of the initial treatment for SCLC. Of the 6 patients, 2 had a solitary brain metastasis and 4 had ≥2 brain metastatic sites. The metastases were identified during a regular check-up computed tomography (CT) scan and were successfully treated. The median interval from the initial diagnosis to the development of brain metastasis was 16 months (range, 13-30 months). All patients received whole-brain irradiation and achieved a complete response. Only one patient developed disturbances of the higher cerebral function. The median interval from whole-brain irradiation to death or last follow-up was 33 months (range, 8-90 months). To the best of our knowledge, these are the first reported cases with isolated brain relapse of SCLC. Although a rare finding, clinicians should be alert on the possibility of such recurrence, particularly in patients who refused prophylactic cranial irradiation.

Isolated solitary brain metastasis as a relapse of small cell lung cancer

The brain is one of the most common sites for the metastasis of small cell lung cancer (SCLC). The present study describes two cases of an isolated solitary brain metastasis as a relapse of SCLC, which occurred more than one year after the completion of the initial successful treatment for SCLC. The tumors were identified during a regular check-up computed tomography (CT) scan and were successfully treated. To the best of our knowledge, this is the first study to report the cases of two patients with an isolated solitary brain metastasis as a relapse of SCLC. Although extremely rare, the possibility of such recurrences should be considered, particularly in patients who have refused prophylactic cranial irradiation.

[Present role of prophylactic cranial irradiation]

Prophylactic cranial irradiation (PCI) plays a role in the management of lung cancer patients, especially small cell lung cancer (SCLC) patients. As multimodality treatments are now able to ensure better local control and a lower rate of extracranial metastases, brain relapse has become a major concern in lung cancer. As survival is poor after development of brain metastases (BM) in spite of specific treatment, PCI has been introduced in the 1970's. PCI has been evaluated in randomized trials in both SCLC and non-small cell lung cancer (NSCLC) to reduce the incidence of BM and possibly increase survival. PCI reduces significantly the BM rate in both limited disease (LD) and extensive disease (ED) SCLC and in non-metastatic NSCLC. Considering SCLC, PCI significantly improves overall survival in LD (from 15 to 20% at 3 years) and ED (from 13 to 27% at 1 year) in patients who respond to first-line treatment; it should thus be part of the standard treatment in all responders in ED and in good responders in LD. No dose-effect relationship for PCI was demonstrated in LD SCLC patients so that the recommended dose is 25 Gy in 10 fractions. In NSCLC, even if the risk of brain dissemination is lower than in SCLC, it has become a challenging issue. Studies have identified subgroups at higher risk of brain failure. There are more local treatment possibilities for BM related to NSCLC, but most BM will eventually recur so that PCI should be reconsidered. Few randomized trials have been performed. Most of them could demonstrate a decreased incidence of BM in patients with PCI, but they were not able to show an effect on survival as they were underpowered. New trials are needed. Among long-term survivors, neuro-cognitive toxicity may be observed. Several approaches are being evaluated to reduce this possible toxicity. PCI has no place for other solid tumours at risk such as HER2+ breast cancer patients.

Menadione : sodium orthovanadate combination eliminates and inhibits migration of detached cancer cells

Exposure of cancer cells to anticancer agents in cultures induces detachment of cells that are usually considered dead. These drug-induced detached cells (D-IDCs) may represent a clinical problem for chemotherapy since they may survive anoikis, enter the circulation, invade other tissues and resume proliferation, creating a metastasis, especially in tissues where the bioavailability of anticancer agents is not enough to eliminate all cancer cells. In this study we evaluated the antiproliferative effect of menadione : sodium orthovanadate (M : SO) combination on A549 lung cancer cells as well as the ability of M : SO to induce cell detachment. In addition, we followed the fate and chemosensitivity of M : SO-induced detached cells. Using transwell chambers, we found that a fraction of the M : SO-induced detached cells were viable and, furthermore, were able to migrate, re-attach, and resume proliferation when re-incubated in drug-free media. The total elimination of A549 detachment-resistant cells and M : SO-induced detached cells were successfully eliminated by equivalent M : SO concentration (17.5 μM : 17.5 μM). Thus, M : SO prevented cell migration. Similar results were obtained on DBTRG.05MG human glioma cells. Our data guarantee further studies to evaluate the in vivo occurrence of D-IDCs, their implications for invasiveness and metastasis and their sensitivity to anticancer drugs.

Factors affecting the risk of brain metastasis in small cell lung cancer with surgery: is prophylactic cranial irradiation necessary for stage I-III disease?

PURPOSE

The use of prophylactic cranial irradiation (PCI) in small cell lung cancer (SCLC) with surgical resection has not been fully identified. This study undertook to assess the factors affecting the risk of brain metastases in patients with stage I-III SCLC after surgical resection. The implications of PCI treatment for these patients are discussed.

METHODS AND MATERIALS

One hundred twenty-six patients treated with surgical resection for stage I-III SCLC from January 1998-December 2009 were retrospectively analyzed to elucidate the risk factors of brain metastases. Log-rank test and Cox regression model were used to determine the risk factors of brain metastases.

RESULTS

The median survival time for this patient population was 34 months, and the 5-year overall survival rate was 34.9%. For the whole group, 23.0% (29/126) of the patients had evidence of metastases to brain. Pathologic stage not only correlated with overall survival but also significantly affected the risk of brain metastases. The 5-year survival rates for patients with pathologic stages I, II, and III were 54.8%, 35.6%, and 14.1%, respectively (P=.001). The frequency of brain metastases in patients with pathologic stages I, II, and III were 6.25% (2/32), 28.2% (11/39), and 29.1% (16/55) (P=.026), respectively. A significant difference in brain metastases between patients with complete resection and incomplete resection was also observed (20.5% vs 42.9%, P=.028). The frequency of brain metastases was not found to be correlated with age, sex, pathologic type, induction chemotherapy, adjuvant chemotherapy, or adjuvant radiation therapy.

CONCLUSIONS

Stage I SCLC patients with complete resection had a low incidence of brain metastases and a favorable survival rate. Stage II-III disease had a higher incidence of brain metastases. Thus, PCI might have a role for stage II-III disease but not for stage I disease.

Outcome of small cell lung cancer (SCLC) patients with brain metastases in a routine clinical setting

BACKGROUND

Small cell lung cancer (SCLC) represents approximately 13 to 18% of all lung cancers. It is the most aggressive among lung cancers, mostly presented at an advanced stage, with median survival rates of 10 to12 months in patients treated with standard chemotherapy and radiotherapy. In approximately 15-20% of patients brain metastases are present already at the time of primary diagnosis; however, it is unclear how much it influences the outcome of disease according the other metastatic localisation. The objective of this analysis was to evaluate the median survival of SCLC patients treated by specific therapy (chemotherapy and/or radiotherapy) with regard to the presence or absence of brain metastases at the time of diagnosis.

PATIENTS AND METHODS

All SCLC patients have been treated in a routine clinical practice and followed up at the University Clinic Golnik in Slovenia. In the retrospective study the medical files from 2002 to 2007 were review. All patients with cytological or histological confirmed disease and eligible for specific oncological treatment were included in the study. They have been treated according to the guidelines valid at the time. Chemotherapy and regular followed-up were carried out at the University Clinic Golnik and radiotherapy at the Institute of Oncology Ljubljana.

RESULTS

We found 251 patients eligible for the study. The median age of them was 65 years, majority were male (67%), smokers or ex-smokers (98%), with performance status 0 to 1 (83%). At the time of diagnosis no metastases were found in 64 patients (25.5%) and metastases outside the brain were presented in 153 (61.0%). Brain metastases, confirmed by a CT scan, were present in 34 patients (13.5%), most of them had also metastases at other localisations. All patients received chemotherapy and all patients with confirmed brain metastases received whole brain irradiation (WBRT). The radiotherapy with radical dose at primary tumour was delivered to 27 patients with limited disease and they got 4-6 cycles of chemotherapy. Median overall survival (OS) of 34 patients with brain metastases was 9 months (95% CI 6-12) while OS of 153 patients with metastases in other locations was 11 months (95% CI 10-12); the difference did not reach the level of significance (p = 0.62). As expected, the OS of patients without metastases at the time of primary diagnosis turned out to be significantly better compared to the survival of patients with either brain or other location metastases at the primary diagnosis (15 months vs 9 and 11 months, respectively, p < 0.001).

CONCLUSIONS

In our investigated population, the prognosis of patients with extensive SCLS with brain metastases at the primary diagnosis treated with chemotherapy and WBRT was not significantly worse compared to the prognosis of patients with extensive SCLC and metastases outside the brain. In extensive SCLC brain metastases were not a negative prognostic factor per se if the patients were able to be treated appropriately. However, the survival rates of extensive SCLC with or without brain metastases remained poor and novel treatment approaches are needed. The major strength of this study is that it has been done on a population of patients treated in a routine clinical setting.

Therapy and prophylaxis of brain metastases

Metastases of various tumors to the brain account for the majority of brain cancers, and are associated with a poor prognosis. The most common primary sites are lung, breast, skin, kidney and colon; 10-40% of cancer patients develop brain metastases during the course of the disease. The incidence of brain metastasis appears to be rising; reasons may include better therapies for the systemic disease with longer survival of cancer patients but lower efficiency against brain metastases. In this article, we will discuss the conventional treatment with surgery, radiosurgery, radiotherapy and chemotherapy, but also new directions in the management of solid brain metastases. While general therapeutic nihilism should be avoided, it is important to recognize that the number of brain metastases, the extent of the systemic disease and also the tumor type have to be taken into account when choosing individual treatment regimens. Finally, special emphasis will be put on established and future approaches to prevent the disease. We thus aim to provide a framework for treating patients with different presentations of brain metastases, and to highlight important avenues for research.

Neurological complications of systemic cancer

Neurological complications of systemic cancer-those arising outside the nervous system-can be distressing, disabling, and sometimes fatal. Diagnosis is often difficult because different neurological disorders may present with similar signs and symptoms. Furthermore, comorbid neurological illnesses, common in elderly patients with cancer, can complicate diagnosis. Early diagnosis and aggressive treatment can improve neurological symptoms and can substantially enhance a patient's quality of life. We approach the problem of neurological complications of systemic cancer as would a neurologist: first by identifying the anatomical area or areas that are affected (ie, brain, spinal cord, peripheral nerve), then by evaluating the diagnostic approach, considering the symptoms and signs and including appropriate laboratory tests, and finally, by recommending treatment. We focus on disorders that are difficult to diagnose, need neurological consultation, and for which effective treatments exist.

Prophylactic cranial irradiation in patients with small-cell lung cancer: the experience at the Institute of Oncology Ljubljana

Background

Prophylactic cranial irradiation (PCI) has been used in patients with small-cell lung cancer (SCLC) to reduce the incidence of brain metastases (BM) and thus increase overall survival. The aim of this retrospective study was to analyze the characteristics of patients with SCLC referred to the Institute of Oncology Ljubljana, their eligibility for PCI, patterns of dissemination, and survival.

Patients and methods

Medical charts of 357 patients with SCLC, referred to the Institute of Oncology Ljubljana between January 2004 and December 2006, were reviewed to determine characteristics of patients chosen for PCI. The following data were collected: age, gender, performance status (PS), extent of the disease, smoking status, type of primary treatment with outcome, haematological and biochemical parameters, PCI use, and finally brain metastases (BM) status at diagnoses and after treatment.

Results

PCI was performed in 24 (6.7%) of all patients. Six (25%) patients developed brain metastases after they were treated with PCI. Brain was the only site of metastases in 4 patients, two progressed to multiple organs. Median overall survival of patients with PCI was 21.9 months, without PCI 12.13 months (p = 0.004). From the collected data there were good prognostic factors: age under 65 years, limited disease (LD), performance status, normal levels of lactate dehydrogenase (LDH) and normal levels of C-reactive protein levels (CRP). Other prognostic factors did not show statistical significant values.

Conclusions

Survival of patients with LD, who have had PCI, was significantly better than those who had not. We decided to perform PCI in patients with LD, in those with complete or near complete response, and those with good performance status (≥ 80). We did not use PCI in extended disease (ED). The reason for that shall be addressed in the future. Doses for PCI were not uniform, therefore more standard approach should be considered.