Enhanced systemic antitumor efficacy of PD-1/PD-L1 blockade with immunological response induced by photodynamic therapy.

BACKGROUND: Photodynamic therapy (PDT) is an antitumor therapy and has traditionally been regarded as a localized therapy in itself. However, recent reports have shown that it not only exerts a direct cytotoxic effect on cancer cells but also enhances body's tumor immunity. We hypothesized that the immunological response induced by PDT could potentially enhance the efficacy of programmed death-1 (PD-1) / programmed death-ligand 1 (PD-L1) blockade. METHODS: The cytotoxic effects of PDT on colon 26 cells were investigated in vitro using the WST assay. We investigated whether the antitumor effect of anti-PD-1 antibodies could be amplified by the addition of PDT. We performed combination therapy by randomly allocating tumor-bearing mice to four treatment groups: control, anti-PD-1 antibodies, PDT, and a combination of anti-PD-1 antibodies and PDT. To analyze the tumor microenvironment after treatment, the tumors were resected and pathologically evaluated. RESULTS: The viability rate of colon 26 cells decreased proportionally with the laser dose. In vivo experiments for combined PDT and anti-PD-1 antibody treatment, combination therapy showed an enhanced antitumor effect compared with the control. Immunohistochemical findings of the tumor microenvironment 10 days after PDT indicated that the number of CD8+ cells, the area of Iba-1+ cells and the area expressing PD-L1 were significantly higher in tumors treated with combination therapy than in tumors treated with anti-PD-1 antibody alone, PDT alone, or the control. CONCLUSIONS: PDT increased immune cell infiltration into the tumor microenvironment. The immunological response induced by PDT may enhance the efficacy of PD-1/PD-L1 blockade.

Long-term outcomes of PDT for centrally-located early lung cancers with tumor diameters > 2.0 cm.

BACKGROUND: Photodynamic therapy (PDT) is used for the treatment of centrally-located early lung cancers (CLELCs) and is recommended for tumors ≤ 1.0 cm in diameter. We previously reported that PDT using talaporfin sodium, second-generation photosensitizer, for tumors > 1.0 cm but ≤ 2.0 cm in diameter was able to achieve a therapeutic outcome comparable to that of tumors with a diameter of ≤ 1.0 cm. However, the effectiveness of PDT using talaporfin sodium for tumors > 2.0 cm in diameter remains unclear. We conducted a retrospective analysis of cases in which PDT was performed for flat-type CLELCs with tumor diameters of > 2.0 cm. METHODS: We retrospectively analyzed seven cases (eight lesions) with tumor diameters > 2.0 cm and no evidence of extracartilaginous invasion or lymph node metastasis. RESULTS: All the patients underwent multiple PDT sessions. The PDT treatment results over the study period were partial response in one case (14.3 %), stable disease (SD) in three cases (42.9 %), and progressive disease (PD) in three cases (42.9 %). At the time of writing this report, five of seven cases (71.4 %) are still undergoing treatment. The duration of SD-the time from the start of treatment until the criteria for PD were met (SD or better maintained)-ranged from 7 to 52 months (mean, 25.3 months). CONCLUSIONS: "Maintenance PDT" for CLELCs > 2.0 cm in diameter has the potential to inhibit tumor progression in the long term while maintaining quality of life, rather than simply aiming only for a quick radical cure.

A remarkable response to combination chemotherapy with nivolumab and ipilimumab in a patient with primary pulmonary choriocarcinoma: a case report.

Background: Primary pulmonary choriocarcinoma (PPC) is a rare malignancy, and only 41 PPC cases have been reported in males up to 2021. Due to its rarity, no standardized treatments for PPC have been established. Cytotoxic chemotherapy has limited efficacy, and the prognosis of advanced PPC is notably poor. Immune checkpoint inhibitors (ICIs) are expected to provide long-term survival for PPC patients, but only a few cases have been reported. The optimal treatment for PPC has not been determined. Case Description: Here, we report a 72-year-old male with post-surgery relapsed PPC, presenting with multiple pulmonary nodules and an intracardiac mass. The OncomineTM Dx target test showed no mutation of cancer-relevant genes, and programmed death-ligand 1 (PD-L1) expression was negative (0%) in the 22C3 assay. He received a combination of carboplatin, paclitaxel, nivolumab, and ipilimumab which is widely used as a first-line treatment for advanced non-small-cell lung cancer (NSCLC). Two months after treatment began, computed tomography (CT) showed multiple lung nodules and an intracardiac mass reduction, which has been sustained for 12 months. Grade 3 febrile neutropenia and grade 2 rash were observed, however, these adverse events were manageable. Conclusions: This is the first case of postoperative relapse PPC that has been successfully treated with the combination of chemotherapy, nivolumab, and ipilimumab. This therapy may be a promising option for advanced PPC.

Development of a new minimally invasive phototherapy for lung cancer using antibody-toxin conjugate.

BACKGROUND: Photodynamic therapy (PDT) is a cancer-targeted treatment that uses a photosensitizer (PS) and laser irradiation. The effectiveness of current PDT using red light for advanced cancers is limited, because red light can only reach depths within a few millimeters. To enhance the antitumor effect for lung cancers, we developed a new phototherapy, intelligent targeted antibody phototherapy (iTAP). This treatment uses a combination of immunotoxin and a PS, mono-L-aspartyl chlorin e6 (NPe6). METHODS: We examined whether cetuximab encapsulated in endosomes was released into the cytosol by PS in PDT under light irradiation. A431 cells were treated with fluorescein isothiocyanate-labeled cetuximab, NPe6, and light irradiation and were observed with fluorescence microscopy. We analyzed the cytotoxicity of saporin-conjugated cetuximab (IT-cetuximab) in A431, A549, and MCF7 cells and the antitumor effect in model A549-bearing mice in vivo using the iTAP method. RESULTS: Fluorescent microscopy analysis showed that the photodynamic effect of NPe6 (20 µM) and light irradiation (37.6 J/cm2 ) caused the release of cetuximab from the endosome into the cytosol. In vitro analysis demonstrated that the iTAP method enhanced the cytotoxicity of IT-cetuximab by the photodynamic effect. In in vivo experiments, compared with IT-cetuximab alone or PDT alone, the iTAP method using a low dose of IT-cetuximab showed the greatest enhancement of the antitumor effect. CONCLUSIONS: Our study is the first report of the iTAP method using NPe6 for lung cancer cells. The iTAP method may become a new, minimally invasive treatment superior to current PDT methods.

New Technique for Introducing a Surgical Stapler during Robot-Assisted Lobectomy for Lung Cancer.

BACKGROUND: The da Vinci Si version robot lacks a vascular stapler that can be controlled by the operating surgeon at the surgical console when dividing pulmonary vessels. Therefore, to initiate and safely perform robotic anatomical lobectomy for lung cancer, it is important to develop a safe method for introducing a surgical stapler. METHODS: We performed a retrospective study of the first 42 consecutive patients who underwent robotic lobectomy for lung cancer at Nippon Medical School Hospital between January 2019 and December 2020. RESULTS: Up to case 18, we performed robot-assisted thoracoscopic surgery (RATS) lobectomy by using a four-arm approach with two assistant ports. For dividing pulmonary vessels, the surgical stapler was introduced through the assist ports. However, since this is not the port position usually used in video-assisted thoracoscopic surgery (VATS), there were many difficult situations. For RATS lobectomy case 19 and all subsequent cases, we utilized a total port approach that uses three robotic arms and two assistant ports. To resect the pulmonary vessels or bronchi with endoscopic staplers, the port for the robotic arm was removed and the endoscopic staplers were placed through a 12-mm Xcel bladeless port. This change reduced operation time, blood loss, and robotic arm interference. No patient developed intraoperative complications during RATS lobectomy. CONCLUSION: The present total port approach, with three robotic arms, appears to be feasible for introducing surgical staplers during RATS with the da Vinci Si robotic system.

Usefulness of simultaneous type image-enhanced endoscope system in photodynamic therapy for centrally located lung cancer.

BACKGROUND: Photodynamic therapy (PDT) is established as one of the standard treatment options for centrally located early lung cancer. In order to improve the effectiveness of PDT, it is very important to accurately diagnose the extent of the tumor and focus the laser irradiation accurately. With the use of the conventional video-endoscope system, which adopts the frame-sequential (RGB-based) display method, mainly used in Japan, for PDT laser irradiation, the system only recognizes the strong white light, and color information is lost. Therefore, it is difficult to irradiate the lesion while simultaneously observing the lesion. In this study, we investigated the usefulness of a new type of video-endoscope system during PDT. METHODS: We used ELUXEO 7000® (FUJIFILM, Japan), which is a simultaneous-type video-endoscope system that has been in use at Nippon Medical School Hospital since October 2018. We analyzed the clinical usefulness of the ELUXEO® system for PDT as compared to other endoscope systems, such as EVIS LUCERA ELITE® (Olympus, Japan), an autofluorescence imaging (AFI) system. RESULTS: After the administration of talaporfin sodium for PDT, the tumor lesion was not visualized in magenta color with AFI, yielding false-negative results. On the other hand, no false-negative results after the administration of talaporfin sodium were obtained with the use of ELUXEO®. Using the ELUXEO® system in the blue light imaging (BLI) mode, we were able to deliver a red laser light while observing the extent of the tumor. Missed laser exposure was avoided and the accuracy of PDT was improved with the use of this system. CONCLUSIONS: ELUXEO® is useful for accurate evaluation of the extent of centrally located lung cancer and therefore, for accurate laser irradiation of the tumor lesion.

Antiaging gene Klotho regulates epithelial-mesenchymal transition and increases sensitivity to pemetrexed by inducing lipocalin-2 expression.

Epithelial-mesenchymal transition (EMT) is considered to serve an important role in the metastatic/invasive ability of cancer cells, in the acquisition of drug resistance, and in metabolic reprogramming. In the present study, it was hypothesized that the Klotho gene is involved in the metastatic/invasive ability of lung cancer. We previously reported an association between Klotho expression and overall survival in patients with small cell lung cancer and large cell neuroendocrine cancer. We also found that Klotho expression was associated with EMT-related molecules in lung squamous cell carcinoma. The present study aimed to analyze the function of the Klotho gene and to elucidate its relevance to the regulation of the EMT. For this purpose, GFP-Klotho plasmids were transfected into lung adenocarcinoma cells (A549) and cell lines with stable expression (A549/KL-1 and A549/KL-2) were established. A549/KL-1 cells expressed higher levels of Klotho protein by western blot analysis compared with A549/KL-2 cells. In western blotting of A549 and A549/KL-1 cells, the expression of the mesenchymal marker N-cadherin was found to be completely inhibited in A549/KL-1 cells suggesting that Klotho expression may regulate the EMT in cancer cells via the inhibition of N-cadherin. The results of the sensitivity tests demonstrated that A549/KL-1 cells were significantly more sensitive to pemetrexed compared with A549 cells (IC50 A549/KL-1 vs. A549 cells, 0.1 µM vs. 0.7 µM). The results of the microarray analysis demonstrated that a very high level of lipocalin-2 (LCN2) expression was induced in the A549/KL-1 cells. Klotho overexpression completely suppressed the expression of mesenchymal markers, such as N-cadherin and Snail1 (Snail). The results of the present study suggested that there may be a new mechanism of action for the antitumor effects of pemetrexed, namely, LCN2-mediated modulation of N-cadherin expression. Klotho expression during cancer treatment has great potential as a predictor for efficacy of pemetrexed and as a factor in the selection of personalized medicine for postoperative adjuvant chemotherapy.

[Therapeutic Strategies for Metachronous Multiple Primary Lung Cancer].

BACKGROUNDS: It is not uncommon to encounter metachronous primary lung cancer after surgical treatment along with the increase in the elderly patients. In consideration of increasing number of such patients, it is necessary to take various treatment strategies. METHODS: In order to establish a treatment strategy for multiple lung cancer, we retrospectively examined multiple lung cancer cases operated for primary lung cancer in our department from January 2013 to December 2019, and the future treatment strategy was examined. RESULTS: Of 821 patients who underwent surgery for primary lung cancer, 61 were multiple lung cancers, 31 were synchronous multiple lung cancers, and 30 were metachronous multiple lung cancers. Among the cases of metachronous multiple lung cancer, 28 cases had undergone lobectomy or more in the first operation, 1 case of segmental resection, and 1 case of partial resection. As for the treatment of secondary lung cancer lesions, 21 lesions were performed surgery( lobectomy;2, segmental resection;2, partial resection;17), 6 lesions of photodynamic therapy (PDT), and 3 lesions of stereotactic body radiation therapy (SBRT). Among the surgical cases, there were three cases on the same side as the first cancer and 18 cases on the opposite side. The three cases underwent partial resection. Among 21 patients, postoperative home oxygen therapy was introduced in 2 patients. Regarding the prognosis, three patients who had surgical resection, died of recurrence of the first lesion. One of the six PDT patients died of recurrence of the first lung cancer and another died of other disease. All three patients who underwent SBRT are alive without recurrence. CONCLUSIONS: If early detection and early diagnosis are made as a treatment strategy for metachronous multiple lung cancer, it may be possible to preserve lung function by reducing surgery or SBRT, PDT, and to cure without damaging the quality of life.

A Case of Pulmonary Adenofibroma Treated by Thoracoscopic Resection.

Pulmonary adenofibroma is a rare biphasic tumor that contains epithelial and stromal components. We report a case of pulmonary adenofibroma in which the tumor was resected by thoracoscopic surgery and the diagnosis was established by histopathology. A 59-year-old woman with a past medical history of pyelonephritis visited our hospital for evaluation of an abnormal opacity on a plain chest x-ray during a comprehensive medical examination. A follow-up chest x-ray showed enlargement of the lesion, and the patient was referred to our department for further management. Chest computed tomography revealed a well-circumscribed nodule measuring 1.4 cm in diameter in the upper lobe of the left lung. The chest imaging findings suggested a benign tumor, but because of evidence of lesion enlargement and elevated serum carcinoembryonic antigen levels, we performed wide wedge resection of the left upper lobe by video-assisted thoracoscopic surgery, for diagnosis and treatment. The resected specimen was submitted for rapid pathological diagnosis during the operation, and a benign tumor, possibly sclerosing pneumocytoma, was suspected. Therefore, we completed the operation with wide wedge resection. The final histopathological diagnosis was pulmonary adenofibroma. The patient had an uneventful postoperative course, and at this writing, 6 months postoperatively, there has been no evidence of tumor recurrence. We have reported this case of pulmonary adenofibroma because the tumor is rare, has not yet been well-characterized, and has an unclear prognosis. Collection of data from a larger number of patients is necessary.

Spontaneous pulmonary hematoma with diffuse pulmonary ossification requiring emergency treatment: a case report.

BACKGROUND: Pulmonary hematoma is most often caused by thoracic trauma. However, rare cases of pulmonary hematoma without any obvious cause are sometimes reported, when the condition is referred to as spontaneous or idiopathic pulmonary hematoma. Herein, we report a very rare case-to the best of our knowledge, this is the first case of pulmonary hematoma associated with diffuse pulmonary ossification requiring emergency treatment reported in the English literature. CASE PRESENTATION: Our patient was a 44-year-old man with a history of IgA nephropathy and had no history of trauma or anticoagulant use. He presented with the chief complaint of bloody sputum and was referred to our hospital for detailed examination. Chest computed tomography showed a right pleural effusion and a large round mass in the right lower lobe. We performed chest tube drainage of the right thorax and confirmed bloody pleural effusion. Although bronchial artery embolization was performed, the patient's anemia worsened, and we performed right lower lobectomy. Histopathological examination of the resected specimen showed a hematoma with diffuse pulmonary ossification, although the relationship between the two was unclear. There was no evidence of malignancy or angiitis. Therefore, we made the diagnosis of spontaneous pulmonary hematoma in this case. The postoperative course was uneventful. The patient is currently under observation as an outpatient, and a recent chest X-ray showed no evidence of recurrence. CONCLUSION: We report a case of spontaneous pulmonary hematoma with diffuse pulmonary ossification. Although the relationship between the two remains unclear, considering the possibility of appearance of new lesions/recurrence, we believe that careful follow-up is necessary for this patient.

[Complete Surgical Resection for Lung Cancer Invading Anterior Apex after Preoperative Chemoradiotherapy Via Transmanubrial Approach and Anterolateral Thoracotomy].

Surgical resection plays an important role as a radical treatment for lung cancers. Many lung cancer patients are found in an advanced state and it is currently in a condition that can not be operated, and the prognosis is also bad. For locally advanced lung cancer, complete resection including surrounding organs is expected by performing chemoradiotherapy before surgery. We report a case of complete surgical resection for lung cancer invading anterior apex after preoperative chemoradiotherapy via transmanubrial approach and anterolateral thoracotomy.