Cerebral metastases in extrapulmonary cell carcinoma. Implications for the use of prophylactic cranial irradiation. Strahlenther Onkol. 2012;188:478-482. [PMID: 22418588 DOI: 10.1007/s00066-012-0084-5]

Small cell bladder cancer: should we consider prophylactic cranial irradiation?

Purpose:

To describe the clinical characteristics, treatment patterns, and outcomes in patients with small cell bladder cancer at our institution, including those who received prophylactic cranial irradiation (PCI) for the prevention of intracranial recurrence.

Materials and Methods:

Patients with small cell bladder cancer treated at a single institution between January 1990 and August 2015 were identified and analyzed retrospectively for demographics, tumor stage, treatment, and overall survival.

Results:

Of 44 patients diagnosed with small cell bladder cancer, 11 (25%) had metastatic disease at the time of presentation. Treatment included systemic chemotherapy (70%), radical surgery (59%), and local radiation (39%). Six patients (14%) received PCI. Median overall survival was 10 months (IQR 4 – 41). Patients with extensive disease had worse overall survival than those with organ confined disease (8 months vs. 36 months, respectively, p = 0.04). Among those who received PCI, 33% achieved 5 - year survival.

Conclusion:

Outcomes for patients with small cell bladder cancer remain poor. Further research is indicated to determine if PCI increases overall survival in small call bladder cancer patients, especially those with extensive disease who respond to chemotherapy.

Ion Channels in Brain Metastasis

Breast cancer, lung cancer and melanoma exhibit a high metastatic tropism to the brain. Development of brain metastases severely worsens the prognosis of cancer patients and constrains curative treatment options. Metastasizing to the brain by cancer cells can be dissected in consecutive processes including epithelial-mesenchymal transition, evasion from the primary tumor, intravasation and circulation in the blood, extravasation across the blood-brain barrier, formation of metastatic niches, and colonization in the brain. Ion channels have been demonstrated to be aberrantly expressed in tumor cells where they regulate neoplastic transformation, malignant progression or therapy resistance. Moreover, many ion channel modulators are FDA-approved drugs and in clinical use proposing ion channels as druggable targets for future anti-cancer therapy. The present review article aims to summarize the current knowledge on the function of ion channels in the different processes of brain metastasis. The data suggest that certain channel types involving voltage-gated sodium channels, ATP-release channels, ionotropic neurotransmitter receptors and gap junction-generating connexins interfere with distinct processes of brain metastazation.

Extrapulmonary small cell carcinoma of lymph node: Pooled analysis of all reported cases

AIM

To study clinical outcomes and management of lymph nodes extrapulmonary small cell carcinoma (LNEPSCC).

METHODS

Herein, we perform a systematic search of published literature in the PubMed and EMBASE databases for studies describing LNEPSCC. For uniformity of reporting, LNEPSCC was staged as limited if it involved either single lymph node station or if surgery with curative intent had been undertaken. The disease was staged extensive if it involved two or more lymph node regions.

RESULTS

The systematic literature review yielded eight descriptions (n = 14) involving cervical, submandibular and inguinal lymph nodes. Eleven (64.7%) patients had limited disease (LD) and six (35.3%) had extensive disease (ED) at presentation. Chemotherapy (n = 6, 35.3%) or surgery (n = 4, 23.5%) were the most common form of treatment given to these patients. Complete response was achieved in 12 (70.6%) of the patients. Median (interquartile range) progression free survival and overall survival was 15 (7-42) mo and 22 (12.75-42) mo respectively. Of the three illustrative cases, two patients each had ED at presentation and achieved complete remission with platinum based combination chemotherapy.

CONCLUSION

LNEPSCC is a rare disease with less than 15 reported cases in world literature. Surgical resection with curative intent is feasible in those with LD while platinum based combination chemoradiation is associated with favorable outcomes in patients with ED. Prognosis of LNEPSCC is better than that of small cell lung cancer in general.

Controversies in small cell carcinoma of the head and neck: Prophylactic cranial irradiation (PCI) after primary complete initial remission

Small cell carcinoma of head and neck region (SmCCHN) represents a rare entity and its management remains a significant clinical challenge. Complete initial response to primary therapy poses a difficult and controversial scenario for radiation oncologists. Prophylactic cranial irradiation (PCI) has long been established in the management of small cell lung cancer; however, its role in SmCCHN is still called into question. The rationale behind PCI lies in the eradication of possible micro-metastatic brain disease, which is often documented in this type of cancer. No randomized trials on this topic are available. This review, based on 20 retrospective studies, addresses the controversies in the use of PCI in SmCCHN management.

Current approaches for prophylactic cranial irradiation in extrapulmonary small cell carcinoma

BACKGROUND

Small cell lung cancer (SCLC) patients, who have achieved complete or partial response after chemotherapy, should be followed with prophylactic cranial irradiation (PCI). PCI for extrapulmonary small cell carcinoma (EPSCC) is not routinely recommended. The purpose of this review is to discuss all aspects of PCI in management of EPSCC.

SCOPE

The PubMed database and the database of online abstracts of the American Society of Oncology (ASCO), ASCO Genitourinary (GU) Cancers meetings and clinical trials were searched up to 15 October 2013 using the following search keywords: 'SCC or EPSCC of each organ site and prophylactic cranial radiotherapy'. The language of screened abstracts and manuscripts was limited to English. The papers which included the largest case series and data of cases about prophylactic cranial radiotherapy and/or were published in the last 10 years were selected.

FINDINGS

Many single center studies showed low incidence of brain metastasis in patients with esophageal small cell carcinoma (SCC). Due to the low incidence of brain metastasis, PCI is not recommended for esophageal SCC. Genitourinary, colorectal, small bowel and appendix cranial metastatic SCCs are extremely rare. Therefore, PCI is not recommended. The frequency of brain metastasis of prostate small cell carcinoma is much higher (16-19%) compared to other counterparts of EPSCC. PCI can be performed in selected cases of prostate SCC. High rates (41%) of brain metastasis develop in head and neck SCC. PCI should be considered for patients with head neck SCC.

CONCLUSION

In the literature, the brain metastasis incidence of EPSCC might vary from 1.7% up to 40%. In many patients with ESPCC, PCI is not recommended. However, we have to keep in mind that primary head and neck and prostate SCC are exceptions due to the high incidence of cranial metastasis; PCI should be recommended for these patients on an individual basis.

Ionizing radiation, ion transports, and radioresistance of cancer cells

The standard treatment of many tumor entities comprises fractionated radiation therapy which applies ionizing radiation to the tumor-bearing target volume. Ionizing radiation causes double-strand breaks in the DNA backbone that result in cell death if the number of DNA double-strand breaks exceeds the DNA repair capacity of the tumor cell. Ionizing radiation reportedly does not only act on the DNA in the nucleus but also on the plasma membrane. In particular, ionizing radiation-induced modifications of ion channels and transporters have been reported. Importantly, these altered transports seem to contribute to the survival of the irradiated tumor cells. The present review article summarizes our current knowledge on the underlying mechanisms and introduces strategies to radiosensitize tumor cells by targeting plasma membrane ion transports.

The first survival score for patients with brain metastases from small cell lung cancer (SCLC)

OBJECTIVE

Survival scores can help physicians select appropriate treatment for patients with brain metastasis. Primary tumors have different biological behavior justifying separate scoring systems for different tumors. In this study, a survival score was developed for patients with brain metastasis from SCLC.

METHODS

Data of 172 patients receiving whole-brain radiotherapy alone for brain metastasis from SCLC were included. Patients were assigned to a test (N=86) or a validation group (N=86). In the test group, Karnofsky Performance Score, number of brain metastases, and extracranial metastasis were associated with survival and included in the score. Scores for each factor were obtained from the 6-month survival rate divided by 10. According to the total scores, which represented the sum of the three scores, three prognostic groups were formed.

RESULTS

6-Month survival rates in the test group were 3% for 5-8 points, 40% for 9-12 points, and 89% for 15 points (p<0.001). In the validation group, 6-month survival rates were 3%, 41%, and 89% (p<0.001). The comparisons between the three prognostic groups of the test group and the validation group did not show significant differences.

CONCLUSIONS

This new score appears valid and reproducible. It can be used to personalize the treatment to patients with brain metastasis from SCLC.