Treatment of recurrent disease in lung cancer

Targeted EGFR Nanotherapy in Non-Small Cell Lung Cancer

Non-small cell lung cancer (NSCLC) remains a leading cause of cancer-related mortality worldwide. Despite advances in treatment, the prognosis remains poor, highlighting the need for novel therapeutic strategies. The present review explores the potential of targeted epidermal growth factor receptor (EGFR) nanotherapy as an alternative treatment for NSCLC, showing that EGFR-targeted nanoparticles are efficiently taken up by NSCLC cells, leading to a significant reduction in tumor growth in mouse models. Consequently, we suggest that targeted EGFR nanotherapy could be an innovative treatment strategy for NSCLC; however, further studies are needed to optimize the nanoparticles and evaluate their safety and efficacy in clinical settings and human trials.

Economic Burden of Recurrence in Completely Resected Stage IB-IIIA Non-Small Cell Lung Cancer: A Retrospective Study Using Nationwide Claims Data of South Korea

INTRODUCTION

Although many patients with early stage non-small cell lung cancer (NSCLC) experience recurrence despite complete resection, few studies have reported on the corresponding economic burden. This study aimed to understand the economic impact of recurrence by measuring healthcare costs and resource utilization in patients with recurrent stage IB-IIIA NSCLC.

METHODS

Using Health Insurance Review and Assessment claims data from South Korea, we included patients who underwent complete resection for stage IB-IIIA NSCLC during the index period (January 1, 2012, to October 31, 2018). Patients who experienced recurrence were matched with those who did not using 1:1 propensity score (PS) matching. The mean healthcare costs and resource utilization were analyzed from the date of complete resection to the last claims for cancer treatment. A generalized linear model (GLM) was used to estimate the impact of covariates on healthcare costs. A difference-in-difference (DID) analysis was conducted to analyze the healthcare costs between the two groups before and after recurrence.

RESULTS

Patients with recurrence incurred higher healthcare costs, particularly in outpatient settings. The cost of targeted therapy and immune checkpoint inhibitors primarily contributed to cost differences, and medication costs increased over time after complete resection. Patients with recurrence were also hospitalized more frequently (9.3 vs. 5.0, p < 0.0001) for a longer period (74 days vs. 42 days, p < 0.0001) than those without recurrence. GLM analysis showed that the total cost was 2.31-fold higher in patients with recurrence (95% confidence interval: 2.19-2.44). The DID analysis showed significantly increased total costs in patients with recurrence (β = 26,269, p < 0.0001), which was mostly attributed to medication costs (β = 17,951, p < 0.0001).

CONCLUSION

Recurrence of completely resected NSCLC leads to a substantial increase in healthcare costs and resource utilization. The results of this study show the economic burden of recurrence, which may help future economic analyses and resource allocation.

Cell-Free DNA in Oncology: Gearing up for Clinic

In the past several years, interest in the clinical utility of cell-free DNA as a noninvasive cancer biomarker has grown rapidly. Success in the development of plasma genotyping assays and other liquid biopsy assays has widened the scope of cell-free DNA use in research and the clinic. Already approved by the US Food and Drug Administration in the narrow context of epidermal growth factor receptor-mutated non-small cell lung cancer, plasma genotyping assays are currently being investigated in a wide array of clinical settings and modalities. These include plasma genotyping as a tool for early diagnosis, the detection of minimal residual disease, and the evaluation of treatment response/progression. In this review, we assess the clinical landscape of plasma genotyping assays and propose strategies for their further expansion into routine clinical care.

Successful treatment of limited-stage small-cell lung cancer in the right mainstem bronchus by a combination of chemotherapy and argon plasma coagulation

The current standard-of-care treatment for patients with limited-stage small-cell lung cancer (SCLC) is concurrent chemoradiotherapy for local and systemic control. However, standard-of-care treatment strategies have not been established for those with limited-stage SCLC who have a history of thoracic radiotherapy due to concerns with complications associated with radiation overdose. A 37-year-old male developed an aspergilloma in the postoperative left thoracic space after he was treated with concurrent chemoradiotherapy for mediastinal type lung adenocarcionoma and subsequent left upper lobectomy for heterochronous dual adenocarcinoma. Fiberoptic bronchoscopy was performed to examine the status of the suspected bronchopleural fistula when a polypoid mass was observed in the right mainstem bronchus. A histological examination showed that the mass was SCLC at a clinical stage of cTisN0M0, stageIA, without local invasion. Since thoracic radiotherapy was not an option due to a previous history of thoracic irradiation, a combination treatment of carboplatin and etoposide was administered for 4 cycles and resulted in good partial response. In addition, argon plasma coagulation (APC) was performed as an alternative to curative radiotherapy on day 22 of the 4th cycle. The 5th cycle was administered 7 days after APC at which the anticancer therapy was completed. The patient remains disease-free 60 months after the completion of treatment, which suggests that this combination therapy may resolve very early-stage SCLC.

Stereotactic Radiosurgery/Stereotactic Body Radiotherapy for Recurrent Lung Neoplasm: An Analysis of Outcomes in 100 Patients

BACKGROUND

A significant number of patients have recurrent or persistent lung cancer despite complete resection or treatment with definitive chemoradiation. Stereotactic radiosurgery (SRS)/stereotactic body radiation therapy is emerging as an important modality for the treatment of early-stage lung neoplasm; SRS may also offer an alternative treatment option for patients with recurrent lung disease. We evaluated outcomes after treatment with SRS for recurrent lung neoplasm in a large series of patients.

METHODS

Selected patients with limited recurrent, persistent, or progressive disease after one or more prior treatments for lung cancer were offered SRS. Thoracic surgeons evaluated all patients, placed fiducials when needed, and planned treatment in close collaboration with radiation oncologists and medical physicists. In our early experience, a single fraction of 20 Gy radiation was prescribed and was subsequently increased to 45 to 60 Gy in three to five fractions. The primary endpoint evaluated was overall survival.

RESULTS

We treated 100 patients with recurrent lung cancer (median age 72 years) with SRS. The postprocedure 30-day mortality rate was 0%; median follow-up was 51 months (range, 5 to 123). The median overall survival for the entire group was 23 months (95% confidence interval: 19 to 41). The probability of 2-year and 5-year overall survival was 49% (95% confidence interval: 40% to 60%) and 31% (95% confidence interval: 23% to 43%), respectively.

CONCLUSIONS

Our experience indicates that SRS is safe, and offers an alternative modality for selected patients with recurrent oligometastatic or persistent lung cancer. Thoracic surgeons should actively participate in SRS and continue to evaluate the efficacy of this treatment strategy.

Factors affecting tumor recurrence after curative surgery for NSCLC: impacts of lymphovascular invasion on early tumor recurrence

BACKGROUND

Although surgery is potentially curative treatment for non-small cell lung cancer (NSCLC), the risk of postoperative disease recurrence is still high. This study was conducted to assess the factors associated with postoperative tumor recurrence in patients who underwent curative surgery for NSCLC.

METHODS

One hundred seventy-one patients who underwent curative surgery for NSCLC were included in this study. Clinicopathological factors of histologic type, pathologic TNM stage, T stage, N stage, lymphovascular invasion (LVI), perineural invasion (PNI), surgical procedure, adjuvant chemotherapy and adjuvant radiotherapy were investigated. Gender, age, and clinicopathologic factors were included in univariate and multivariate analyses using the Kaplan-Meier method and Cox proportional hazards model, respectively. Mann-Whitney U and Kruskal-Wallis tests were used to investigate the significance of differences in recurrence-free interval (RFI) according to clinicopathological factors.

RESULTS

Median RFI was 20 months. Univariate and multivariate analyses for overall recurrence identified T stage, N stage, and LVI as significant factors (P=0.045, 0.044, and <0.001, respectively). Pathologic stage (P=0.005) was the only factor that was significantly associated with locoregional recurrence. T stage (P=0.040) and LVI (P<0.001) were significantly associated with distant recurrence. The difference in 2-year freedom from recurrence between LVI positive and negative groups was significant (14.9% vs. 44.6%, P<0.001). LVI was the only factor that was significantly associated with a shortened mean RFI (P<0.001).

CONCLUSIONS

LVI had a significant effect on both overall and distant recurrence rates as well as on early tumor recurrence after curative surgery for NSCLC.

Protein nanocages for self-triggered nuclear delivery of DNA-targeted chemotherapeutics in Cancer Cells

A genetically engineered apoferritin variant consisting of 24 heavy-chain subunits (HFn) was produced to achieve a cumulative delivery of an antitumor drug, which exerts its cytotoxic action by targeting the DNA at the nucleus of human cancer cells with subcellular precision. The rationale of our approach is based on exploiting the natural arsenal of defense of cancer cells to stimulate them to recruit large amounts of HFn nanoparticles loaded with doxorubicin inside their nucleus in response to a DNA damage, which leads to a programmed cell death. After demonstrating the selectivity of HFn for representative cancer cells compared to healthy fibroblasts, doxorubicin-loaded HFn was used to treat the cancer cells. The results from confocal microscopy and DNA damage assays proved that loading of doxorubicin in HFn nanoparticles increased the nuclear delivery of the drug, thus enhancing doxorubicin efficacy. Doxorubicin-loaded HFn acts as a "Trojan Horse": HFn was internalized in cancer cells faster and more efficiently compared to free doxorubicin, then promptly translocated into the nucleus following the DNA damage caused by the partial release in the cytoplasm of encapsulated doxorubicin. This self-triggered translocation mechanism allowed the drug to be directly released in the nuclear compartment, where it exerted its toxic action. This approach was reliable and straightforward providing an antiproliferative effect with high reproducibility. The particular self-assembling nature of HFn nanocage makes it a versatile and tunable nanovector for a broad range of molecules suitable both for detection and treatment of cancer cells.

Three-dimensional conformal reirradiation for locoregionally recurrent lung cancer previously treated with radiation therapy

BACKGROUND

To evaluate the efficacy and toxicity of reirradiation using three-dimensional conformal radiotherapy (3D-CRT) in symptomatic patients with locoregionally recurrent lung cancer.

METHODS

Between 2005 and 2012, 15 patients with locoregionally recurrent lung cancer were retreated with 3D-CRT after previously receiving thoracic radiotherapy. The median interval between the initial irradiation and reirradiation was 12 months (range, five to 41 months). The median initial radiotherapy dose was 63 Gy (range, 45-70 Gy), and reirradiation doses ranged from 25.2 to 45.2 Gy (median, 36 Gy), with daily fractions of 1.8-4 Gy (median, 2 Gy).

RESULTS

After reirradiation, 80% of the patients experienced resolved or diminished symptoms for one or more of their symptoms, with an 83% improvement in a total of 24 symptoms. The overall tumor response rate to reirradiation was 46.7%, with progressive disease occurring in only one patient. The median overall survival (OS) time was 11 months (range, one to 27 months), and the one-year OS rate was 47%. The progression-free survival time ranged from one to 10 months (median, five months). In univariate analysis, the use of combined chemotherapy and a higher reirradiation dose showed a trend toward improved survival after reirradiation. Treatment-induced toxicity included grade 2 radiation pneumonitis in only one patient, and there were no other complications, such as radiation esophagitis or myelopathy.

CONCLUSIONS

Reirradiation using 3D-CRT with moderate doses for locoregionally recurrent lung cancer can provide palliative benefits without severe complications to the majority of selected patients with symptoms as a result of a regrowing tumor.

Salvage stereotactic ablative irradiation for isolated postsurgical local recurrence of lung cancer

BACKGROUND

For isolated postsurgical local recurrences (IPSLR) of lung cancer, salvage resection is often unfeasible due to a high risk of morbidity and death. Stereotactic ablative body radiotherapy (SABR) provides excellent therapeutic effects, with mild toxicities, for patients with medically inoperable lung cancer. However, the outcomes of SABR for IPSLR have not been reported.

METHODS

Patients with IPSLR who were treated with SABR between 2005 and 2012 were retrospectively identified. The prescribed doses were 40 to 60 Gy per 5 to 10 fractions. Treatment outcomes and toxicities were evaluated.

RESULTS

We identified 23 patients with IPSLR, including 21 with bronchial stump or staple line recurrences and 2 with chest wall recurrences. During follow-up, IPSLR occurred at a median of 36.7 months (range, 5.0 to 190 months) after resection. All patients were N0 M0, and the T stages at recurrence were T1a, T1b, T2a, and T4 in 6, 5, 3, and 9 patients, respectively. The initial pathologic diagnoses were adenocarcinoma in 17 patients and squamous cell carcinoma in 6. At a median follow-up duration of 17.0 months (range, 6.0 to 89.6 months) after SABR, there were 2 local recurrences. Local control and overall survival rates at 1 and 2 years were 94.7% and 86.8% and 84.0% and 76.4%, respectively. Grade 3 to 5 radiation pneumonitis occurred in 1 patient each. Grade 3 temporary but repeated obstructive pneumonia occurred in 2 patients.

CONCLUSIONS

SABR for IPSLR achieved high local control with limited toxicities. SABR may lead to a potential cure and should be considered as a salvage treatment option for IPSLR.

Definitive high-dose-rate endobronchial brachytherapy of bronchial stump for lung cancer after surgery

PURPOSE

The aim of this work was to evaluate outcomes after definitive high-dose-rate endobronchial brachytherapy (HDR-BT) for lung cancer.

METHODS AND MATERIAL

We treated 34 patients after surgery for lung cancer, without nodal or distant metastases, with HDR-BT. Two groups were analyzed, one with local recurrence in stump after prior surgery (n = 13) and a second with nonradical primary lobar resection found in histopathologically positive margins (n = 21). There were 27 men and 7 women with a median age of 57.4 years. Twenty-five patients received sole brachytherapy with 4 fractions of 7.5 Gy and 9 received combined treatment consisting of 2 fractions of 6 Gy (HDR-BT) and 50 Gy from external beam radiotherapy. Overall survival time (OS) and overall disease-free survival time (OFS) were compared with prognostic factors.

RESULTS

The complete local and radiologic response rate evaluated at the first month after HDR-BT was 73.5% (25/34). The partial response rate was 26.5%. OFS time in total group was 17.4 months; OS was 18.8 months. Differences were found in OS between both groups-primary tumor or recurrence (log-rank test, p = 0.048). Differences were not found according to gender (p = 0.36), clinical stage (p = 0.76), histopathology (p = 0.93), treatment dose (p = 0.45), sole or combined treatment (p = 0.16), or grade of remission in week 4 (p = 0.15).

CONCLUSIONS

HDR-BT of a stump recurrence or after nonradical resection leads to a long-term OS rate in patients with localized lung cancer and could be considered curative. We found no correlations between OS and chosen clinical data; adjuvant HDR-BT gave better results.

Reirradiation and stereotactic radiotherapy for tumors in the lung: dose summation and toxicity

PURPOSE

To assess the accumulated dose and the toxicity after reirradiation for tumors in the lung using non-rigid registration.

MATERIAL AND METHODS

Twenty patients with a tumor in the lung were reirradiated with or after stereotactic radiotherapy. The summed dose distribution was calculated using non-rigid registration. All doses were recalculated to an equivalent dose of 2 Gy per fraction (EQD2). The median follow-up time was 12 months (range 2-52).

RESULTS

The median Dmax of the lung in the summed plans was 363 Gy3 (range 123-590). The median accumulated V20 of the lungs was 15.2%. Seven patients had in the heart and the trachea an accumulated dose ≥70 Gy3, with a median D(max) of the heart of 115 Gy3 and 89 Gy3 for the trachea. Eight patients had in the esophagus an accumulated dose ≥70 Gy3, with a median accumulated dose of 85 Gy3. No grade 3-5 toxicity was observed.

CONCLUSION

Reirradiation of the lung with or after stereotactic radiotherapy is feasible to a median Dmax of 363 Gy3 to the lung, as low toxicity was observed.

Ponicidin inhibits monocytic leukemia cell growth by induction of apoptosis

In this study two monocytic leukemia cell lines, U937 and THP-1 cells, were used to investigate the anti-proliferation effects caused by ponicidin. Cell viability was measured by an MTT assay. Cell apoptosis was assessed by flow cytometry as well as DNA fragmentation analysis. Cell morphology was observed using an inverted microscope and Hoechst 33258 staining. RT-PCR and Western blot analysis were used to detect survivin as well as Bax and Bcl-2 expressions after the cells were treated with different concentrations of ponicidin. The results revealed that ponicidin could inhibit the growth of U937 and THP-1 cells significantly by induction of apoptosis. The suppression was in both time- and dose-dependent manner. Marked morphological changes of cell apoptosis were observed clearly after the cells were treated with ponicidin for 48 approximately 72 h. RT-PCR and Western blot analysis demonstrated that both survivin and Bcl-2 expressions were down-regulated remarkably while Bax expression remained constant before and after apoptosis occurred. We therefore conclude that ponicidin has significant anti-proliferation effects by inducing apoptosis on leukemia cells in vitro, downregulation of survivin as well as Bcl-2 expressions may be the important apoptosis inducing mechanisms. The results suggest that ponicidin may serve as potential therapeutic agent for leukemia.

Isolation and characterization of radiation-resistant lung cancer D6-R cell line

OBJECTIVE

To isolate an isogenic radioresistant cancer cell line after fractioned X-ray radiation and characterize the resistant cells.

METHODS

D6 cells were exposed to repeated X-ray irradiation, and after a total dose of 5200 cGy in 8 fractions, a radioresistant monoclone D6-R was obtained. The radiosensitivity and drug sensitivity of the novel radioresistant D6-R cells, together with their parent D6 cells, were measured using clonogenic assay and MTT assay respectively. Cell cycle distribution was analyzed by flow cytometry. Fluorescence microscopy and flow cytometry were applied for apoptosis detection. Comet assay was used for the detection of DNA damage and repair.

RESULTS

D6-R cells showed higher and broader initial shoulder (D0=2.08 Gy, Dq=1.64 Gy, N=2.20) than the parent D6 cells (D0=1.84 Gy, Dq=0.34 Gy, N=1.20). They were 1.65-fold more radioresistant than D6 cells in terms of SF2 (63% vs 38%) and were more resistant to ADM (3.15-fold) and 5-FU (3.86-fold) as compared with the latter. It was found that D6-R cells had higher fractions of cells in S phase (53.4% vs 37.8%) and lower fractions of cells in G1 (44.1% vs 57.2%) and G2-M phase (2.5% vs 5%). There was no difference in radiation-induced apoptosis between D6-R and D6 cells. D6-R cells showed less initial DNA damage and increased capacity in DNA repair after irradiation, as compared with the parent cells.

CONCLUSIONS

D6-R cells have been isolated by exposing the parental D6 cells to repeated irradiation. The difference in cell cycle pattern together with the induction and repair of DNA damage might, at least partially, explain the mechanism of the radioresistance.

Special topics in immunotherapy and radiation therapy: reirradiation and palliation

Immunotherapy has revolutionized the treatment of non-small cell lung cancer (NSCLC). However, thus far, its use has only been established in patients with advanced disease either as first-line therapy in selected patients or following chemotherapy. What is not yet known is how best to incorporate radiation with immunotherapy agents. Many patients with advanced disease can benefit from palliative radiation, but the combination of radiation with immunotherapy has the potential to increase the toxicity of both modalities. Intriguingly, the combination also has the potential to enhance the efficacy of both modalities. For this reason, combining immunotherapy and radiation may help salvage patients with recurrent localized disease who are candidates for re-irradiation. We review the current data evaluating immunotherapy with both palliative radiation as well as definitive re-irradiation in NSCLC.

Follow up and surveillance of the patient with lung cancer: What do you do after surgery?

Of the new cases of lung cancer discovered each year, it has been estimated that 50-55% have localized disease and are thus candidates for potentially curative treatment. Some of these patients will refuse surgery or will have co-morbidities that preclude surgery. The remainder will undergo an attempted curative resection. A common clinical question arises in these patients: how should this patient be followed after surgery? Post-treatment surveillance is indicated to monitor for recurrence of the original tumor and for the development of a metachronous tumor. The appropriate protocol is controversial and current recommendations are primarily expert opinion or consensus-based and await further study. A suggested clinically reasonable and cost-effective surveillance approach would include a history, physical examination and an imaging study (either chest radiograph or CT) every 6 months for 2 years and then annually. Patients should be counselled on symptom recognition and advised to contact their physician should such symptoms appear.

Ponicidin, an ent-kaurane diterpenoid derived from a constituent of the herbal supplement PC-SPES, Rabdosia rubescens, induces apoptosis by activation of caspase-3 and mitochondrial events in lung cancer cells in vitro

Ponicidin, an ent-kaurane diterpenoid derived from a constituent of the herbal supplement PC-SPES, Rabdosia rubescens, is recently reported to have anti-tumor effects on a large variety of cancers. In this study, we demonstrate that ponicidin exhibits cytotoxicity, induces apoptosis, disrupts the mitochondrial membrane potential, and triggers the activation of caspase-3, -8 and -9 in lung cancer A549 and GLC-82 cells. Ponicidin treatment of lung cancer cells caused downregulation of anti-apoptotic protein Bcl-2 and survivin as well as upregulaton of pro-apoptotic protein Bax in a time dependent manner when apoptosis ocurred. Ponicidin induced activation of caspase-3 can be blocked by a caspase-3-specific inhibitor z-DEVD-FMK Furthermore, the caspase-8-specific inhibitor z-IETD-FMK could block the ponicidin-induced activation of caspase-3, PARP cleavage, and prevented the release of cytochrome c from mitochondria into the cytoplasm. This indicate that activated caspase-8 initiates the release of cytochrome c during ponicidin-induced apoptosis. We therefore conclude that ponicidin has significant apoptosis-inducing effects by activation of caspase-3 -8, and -9 as well as downregulation of anti-apoptotic protein Bcl-2, survivin and upregulation of pro-apoptotic protein Bax, with caspase-8 acting as an upstream activator. The data offer a potential mechanism for ponicidin-induced apoptosis in lung cancer cells, suggesting that ponicidin may severve as an effective reagent for the treatment of lung cancer, and that in vivo anti-cancer effects as well as its potential clinical effectiveness need further investigation.

Teaching cancer cells to die

Tumor cells have evolved numerous mechanisms to thwart apoptosis. As our understanding of the machinery which regulates cell-death evolves, these apoptotic defects have fallen into the crosshairs of cancer drug developers. The issues raised in exploiting these alterations for therapeutic benefit are discussed.