Endobronchial brachytherapy with curative intent: the impact of reference points setting according to the bronchial diameter

Endobronchial brachytherapy as definitive treatment for endobronchial metastasis after surgery of non-small cell lung cancer

Background

Endobronchial metastasis is a very rare type of recurrence after lung cancer surgery. Surgical intervention may be difficult to perform due to the postoperative reduction in the activities of daily living (ADL) and the invasiveness associated with redo surgery. In such cases, endobronchial brachytherapy (EBBT) plays an important role not only as a palliative treatment, but also as a definitive treatment with curative intent.

Case presentation

Three men (64, 69, and 74 years old) underwent combination therapy of external beam radiation therapy (EBRT) and EBBT for endobronchial metastasis after lobectomy of stage I–II non-small cell lung cancer (NSCLC): 2 cases of squamous cell carcinoma and 1 of adenocarcinoma. We used a special source-centralizing applicator for EBBT to avoid eccentric distribution of the radiation dose. Follow-up was considered to start from the end of brachytherapy. None of our patients experienced severe adverse events, and none needed extensive outpatient treatment. Local control was achieved in all cases by a bronchoscopic evaluation. All patients were alive after 31, 38, and 92 months of follow-up, respectively. In the adenocarcinoma patient, two metastases to the lung were discovered 3 years after EBBT, and the patient underwent partial wedge resection.

Conclusions

EBBT may be a promising treatment with curative intent for endobronchial metastasis after surgery of NSCLC.

Endobronchial brachytherapy combined with surgical procedure for synchronous multiple primary lung cancer: A case report

The management of synchronous multiple primary lung cancer is a challenge. In this report, we describe our experience in a patient with three synchronous multiple cancers. The first lesion was completely surgically removed, the second lesion received postoperative irradiation, and the third lesion was treated with radiotherapy alone. Radiation therapies were performed using a combination of external irradiation and endobronchial brachytherapy. Endobronchial brachytherapy is an effective radiation therapy for endobronchial tumors owing to its advantage of high-dose concentration. However, adverse events (AEs) such as hemoptysis or severe bronchitis are a problem. Thus, we have developed an applicator to keep the radioactive source in the center of the bronchial lumen. A total of 28 months after treatment, the patient had not experienced any relapses or AEs. Endobronchial brachytherapy using an applicator can be an alternative treatment for cases in which surgery is expected to lead to pulmonary dysfunction.

Modern development of high-dose-rate brachytherapy

Brachytherapy is an invasive therapy with placement of radiation source into or near the tumor. The difference between planning target volume and clinical target volume is minimal, and the dose out of the tumor reduces rapidly due to the inverse-square law. High-dose-rate brachytherapy enables three-dimensional image guidance, and currently, tumor dose as well as doses of the surrounding normal structures can be evaluated accurately. High-dose-rate brachytherapy is the utmost precision radiation therapy even surpassing carbon ion therapy. Biological disadvantages of high-dose rate have been overcome by the fractional irradiation. High-dose-rate brachytherapy is indispensable in the definitive radiation therapy of cervical cancer. Also in prostate cancer and breast cancer, high-dose-rate brachytherapy plays a significant role. Brachytherapy requires techniques and skills of radiation oncologists at the time of invasive placement of the radiation source into the tumor area. Education of young radiation oncologists is most urgent and important.

Role of bronchoscopy in management of central squamous cell lung carcinoma in situ

Squamous cell carcinoma in situ (SCIS) is the pre-invasive stage of squamous cell carcinoma. Early detection and management of SCIS can prevent further progression. Although surgery and external beam radiation therapy are treatment options for SCIS, smaller lesions can be easily managed by bronchoscopic modalities like photodynamic therapy (PDT), cryotherapy, mechanical debulking with biopsy forceps, electrocautery and argon plasma coagulation (APC). Endobronchial brachytherapy (EBBT) and lasers may be judiciously utilized in selected cases. Although, previous studies of treatment modalities may have inadvertently included cases of invasive carcinomas, the advent of new technologies like radial probe endobronchial ultrasound (RP-EBUS) and optical coherence tomography (OCT) can help accurately determine the of depth of invasion. Superficial extent can also be better demarcated with techniques like auto-fluorescence bronchoscopy and narrow band imaging (NBI). New drugs for PDT with deeper penetration and less phototoxicity are being developed. These advances hopefully will allow us to perform superior clinical trials in future and improve our understanding of diagnosis and management of SCIS.

Heat stress combined with lipopolysaccharide alter the activity and superficial molecules of peripheral monocytes

The purpose of this study was to focus on the underlying relationship between the hyperactivity for the peripheral monocytes and heat stroke by investigating the inflammatory oxidative activity of and the expression of superficial molecules. Peripheral blood samples were collected from 10 healthy adult volunteers. Human blood monocytes were isolated by density gradient centrifugation and sequent adherent culture. The objectives were divided into four groups: 43°C heat stress combined with lipopolysaccharide (LPS) group, 43°C heat stress group, LPS group, and control group. There were 10 cases in each group. An enzyme-linked immunosorbent assay (ELISA) test was used to measure the concentrations of supernatant inflammatory mediators (tumor necrosis factor alpha (TNF-α), interleukin-1β (IL-1β) and interleukin-10 (IL-10)). After loaded by 2,7-Dichlorodi-hydrofluorescein-diacetate (DCFHDA) fluorescent probe, intracellular reactive oxygen species (ROS) levels were determined by a flow cytometry. After fluorescent microspheres incubation, the phagocytosis of monocytes was observed under a fluorescent microscope. Respectively, the flow cytometry and Western blot were used to evaluate the level of triggering receptor expressed on myeloid cells-1 (TREM-1) and Toll-like receptor-4 (TLR-4) on the monocytes. Furthermore, the mRNA expression of TREM-1 and TLR-4 was detected by real-time polymerase chain reaction (RT-PCR). The heat stress combined with LPS stimulation promoted the peripheral monocytes to produce inflammatory mediators (TNF-α, IL-1β, and IL-10) and release ROS. Otherwise, such complex strike significantly suppressed the phagocytic activity of monocytes in peripheral blood. Moreover, the expression of TREM-1, TLR-4 and CD86 was measured by the flow cytometry on peripheral monocytes which were respectively promoted by the union of heat stress and LPS. The results of Western blot and RT-PCR demonstrated the similar kinetics on these superficial molecules (TREM-1, TLR-4, and CD86) stimulated by the combination of heat stress and LPS. The underlying mechanism of the dysfunction for the peripheral monocytes may be related to the abnormal expression of superficial molecules TREM-1, TLR-4, and CD86 on the monocytes induced by heat stress and LPS.