The consecutive impact of COVID-19 on thoracic surgical procedures in Japan: an analysis of data from the National Clinical Database

PURPOSE

The current study was designed to analyze the impact of the COVID-19 pandemic on general thoracic surgeries in Japan.

METHODS

Changes in surgeries for lung cancer and metastatic lung tumors were evaluated based on National Clinical Database data regarding cancer screening.

RESULTS

In 2021, surgeries for primary lung cancer increased by 3.4% compared to 2020, which, given the increase from 2014 to 2019, indicates an overall 11.1% decrease. In contrast, surgeries for metastatic lung tumors in 2021 decreased by 5.8% compared to 2020, which, given the increase from 2014 to 2020, indicates an overall 9.2% decrease. Half of the primary diseases for metastatic lung tumor were cases of colorectal cancer. Low anterior resection procedures in 2020 decreased by 5.5% compared to 2019. Lung and colon cancer screening examinees in 2021 were increased compared to 2020; however, they still showed respective decreases of 11% and 9.0% compared to 2019.

CONCLUSIONS

Surgeries for primary lung cancer still decreased substantially during the COVID-19 pandemic. The continued stagnation of screening was responsible for this decrease. Surgeries for metastatic lung tumors decreased profoundly, and the decrease in screening for primary tumors was responsible for this reduction. Our findings emphasize the significance of maintaining cancer screening efforts, even during a pandemic.

Multiple cavitary lung lesions from colorectal cancer responding to chemotherapy

Lung metastasis is an uncommon cause of multiple cavitary lung lesions. Herein, we report a case of multiple cavitary lung lesions of colorectal cancer that responded to chemotherapy. An 81-year-old woman was referred to our hospital for abdominal pain. Computed tomography revealed multiple cavitary lung lesions. The patient was diagnosed with lung metastases from colorectal cancer with a lower gastrointestinal endoscopy and bronchoscopy. Following chemotherapy, the cavitary lung lesions shrank. Lung metastases from colorectal cancer may appear as multiple cavitary lung lesions, which may be misdiagnosed as infections. Clinicians should consider lung metastases when multiple cavitary lung lesions are detected.

Metastatic lung tumor from hepatocellular carcinoma with tumor thrombus invasion in the pulmonary vein: a case report

BACKGROUND

Metastatic lung tumor with a tumor thrombus in the peripheral pulmonary vein is very rare. We present a case of a metastatic lung tumor from hepatocellular carcinoma (HCC) with tumor thrombus invasion in the pulmonary vein that was diagnosed preoperatively and underwent complete resection by segmentectomy.

CASE PRESENTATION

A 77-year-old man underwent laparoscopic lateral segment hepatectomy for HCC eight years ago. Protein induced by vitamin K absence or antagonist-II remained elevated from two years ago. Contrast-enhanced chest computed-tomography (CT) showed a 27 mm nodule in the right apical segment (S1). He was pathologically diagnosed with a metastatic lung tumor from HCC via transbronchoscopic biopsy. We planned to perform right S1 segmentectomy. Before surgery, contrast-enhanced CT in the pulmonary vessels phase for three-dimensional reconstruction showed that the tumor extended into the adjusting peripheral pulmonary vein, and we diagnosed tumor thrombus invasion in V1a. The surgery was conducted under 3-port video-assisted thoracic surgery. First, V1 was ligated and cut. A1 and B1 were cut. The intersegmental plane was cut with mechanical staplers. Pathological examination revealed moderately-differentiated metastatic HCC with tumor thrombus invasions in many pulmonary veins, including V1a. No additional postoperative treatments were performed.

CONCLUSIONS

As malignant tumors tend to develop a tumor thrombus in the primary tumor, it might be necessary to perform contrast-enhanced CT in the pulmonary vessel phase to check for a tumor thrombus before the operation for metastatic lung tumors.

Stereotactic ablative body radiotherapy with a central high dose using CyberKnife for metastatic lung tumors

BACKGROUND

The CyberKnife system features a robotically-positioned linear accelerator to deliver real-time image-guided stereotactic ablative body radiotherapy (SABR). It achieves steep dose gradients using irradiation from hundreds of different directions and increases the central dose of the gross tumor volume (GTV) without increasing the marginal dose to the planning target volume. We evaluated the effectiveness and safety of SABR with a central high dose using CyberKnife for metastatic lung tumors.

METHODS

A total of 73 patients with 112 metastatic lung tumors treated with CyberKnife were retrospectively analyzed. Local control, progression-free survival, and overall survival were calculated using the Kaplan-Meier method. The median age was 69.2 years. The most common primary sites were the uterus (n = 34), colorectum (n = 24), head and neck (n = 17), and esophagus (n = 16). For peripheral lung tumors, the median radiation dose was 52 Gy in 4 fractions, whereas for centrally located lung tumors, it was 60 Gy in 8-10 fractions. The dose prescription was defined as 99% of the solid tumor components of the GTV. The median maximum dose within the GTV was 61.0 Gy. The GTV and planning target volume were enclosed conformally by the 80% and 70% isodose lines of the maximum dose, respectively. The median follow-up period was extended to 24.7 months; it was 33.0 months for survivors.

RESULTS

The 2-year local control, progression-free survival, and overall survival rates were 89.1%, 37.1%, and 71.3%, respectively. Toxicities of grade ≥ 2 were noted as grade 2 and 3 radiation pneumonitis in one patient each. The two patients with grade 2 or higher radiation pneumonitis had both received simultaneous irradiation at two or three metastatic lung tumor sites. No toxicity of grade ≥ 2 was observed in patients with metastasis in one lung only.

CONCLUSIONS

SABR with a central high dose using CyberKnife for metastatic lung tumors is effective with acceptable toxicity.

TRIAL REGISTRATION

Number: 20557, Name: Stereotactic ablative radiotherapy using CyberKnife for metastatic lung tumor, URL: http://www.radonc.med.osaka-u.ac.jp/pdf/SBRT.pdf , Date of registration: April 1, 2021 (retrospectively registered), Date of enrollment: May 1, 2014.

Thyroid transcription factor-1 expression in rectal adenocarcinoma metastatic to the lung

Distinguishing metastatic lung tumors from primary lung cancer is essential for planning the appropriate treatment strategy. Thyroid transcription factor-1 (TTF-1) is a reliable immunohistochemistry (IHC) marker for differentiating between primary lung adenocarcinomas and metastatic lung tumors originating from colorectal adenocarcinomas. Herein, we report a rare case of TTF-1 expression in both the metastatic lung tumor and primary rectal adenocarcinoma. Aside from the similar histological characteristics of both tumors when stained with hematoxylin-eosin, the IHC patterns, including negative results for alveolar epithelium markers (napsin A and CK7) and positive results for intestinal markers (CK20, CDX2, SATB2, and β-catenin), of the lung tumor and the primary rectal adenocarcinoma strongly supported the final diagnosis. Considering the non-negligible frequency of TTF-1 positivity in colorectal adenocarcinomas, applying the IHC panel including multiple markers for alveolar epithelium and intestinal differentiation, would be helpful to support the diagnosis of metastatic lung tumor from a rectal adenocarcinoma.

Long-term survival of two patients with pancreatic cancer after resection of liver and lung oligometastases: a case report

Background

The efficacy of resection of pancreatic cancer metastases has not been established. We here report two patients with long-term survival after resection of lung and liver metastases.

Case presentation

The first patient underwent distal pancreatectomy for pancreatic cancer. One year later, she underwent partial hepatectomy for a single liver metastasis. She subsequently underwent pulmonary resections 7, 7.5, 9, and 10 years later for pulmonary metastases from pancreatic cancer. Thus, this patient underwent five surgeries for metastases, one for a liver metastasis and four for lung metastases. All of the tumors were pathologically diagnosed as metastatic pancreatic cancer. She is currently alive without new recurrence 10 years after the initial diagnosis. The second patient underwent pancreaticoduodenectomy for pancreatic cancer. Four years later, she underwent a thoracoscopic partial resection for lung metastasis. The tumor was similar to the pancreatic cancer on pathological examination. She is currently alive without new recurrences 6 years after the initial diagnosis.

Conclusion

Long-term survival can be achieved in some patients with pancreatic cancer by resection of metachronous liver or lung metastases.

Ciliated muconodular papillary tumor with a growing cavity shadow that mimicked colorectal metastasis to the lung: a case report

Background

Ciliated muconodular papillary tumor (CMPT) is a rare papillary nodule tumor with benign and malignant characteristics that occurs in the peripheral lung.

Case presentation

A 70-year-old woman who underwent right hemicolectomy for colorectal cancer (CRC; pT3N0M0, p-stage II) 2 years prior, presented with a sub-centimeter growing cavity shadow on chest computed tomography (CT), which was suspected to be a CRC metastasis. Because positron emission tomography CT suggested there was no other site suspicious of recurrence, thoracoscopic resection with preoperative pleural dye marking was planned to remove the small lesion, which seemed to be hardly palpable on CT. Immediately after pleural dye marking adjacent to the lesion using cone beam CT in the hybrid operating room, thoracoscopic wedge resection was performed and the tumor was finally diagnosed as CMPT, characterized by the papillary growth of mucus-producing cells in the alveoli.

Conclusion

We resected the non-palpable small lung lesions following preoperative marking using cone-beam CT in the hybrid operating room. This case highlights a rare cavitary CT image of a CMPT mimicking a metastatic lung tumor from colorectal cancer.

The neutrophil-to-lymphocyte ratio as a novel independent prognostic factor for multiple metastatic lung tumors from various sarcomas

PURPOSE

Sarcomas are among the most refractory malignant tumors and often recur as pulmonary metastasis. Although the presence of a high neutrophil-to-lymphocyte ratio (NLR) has been associated with the prognosis of several malignancies, the relationship between the NLR and sarcoma with pulmonary metastasis is unclear. We investigated the impact of the NLR in patients who underwent surgical resection for metastatic lung tumors from various sarcomas.

METHODS

The subjects of this retrospective study were 158 patients with metastatic lung tumors from various sarcomas, who underwent initial pulmonary metastasectomy between 2006 and 2015. We examined the clinicopathological variables, including the NLR and the characteristics of surgical procedures. Survival was estimated by the Kaplan-Meier method and prognostic factors were evaluated by multivariate analysis.

RESULTS

Multivariate analysis revealed significantly better survival of the group with an NLR < 2.26 immediately before the most recent pulmonary metastasectomy, in addition to such factors as the largest resected lesion being < 22 mm, a disease-free interval of > 2 years, and 3 or more pulmonary metastasectomies.

CONCLUSION

The NLR immediately before the most recent pulmonary metastasectomy is a novel independent prognostic factor, which may be helpful when considering repeated pulmonary metastasectomy.

Lung metastasis from gastric cancer presenting as diffuse ground-glass opacities

Most metastatic lung tumors display well-defined, round, multiple nodular shadows, whereas the presence of diffuse ground-glass opacities on chest computed tomography generally suggests non-malignant conditions. Here, we report an unusual case of pulmonary metastasis from gastric cancer in which diffuse ground-glass opacities were observed in all lung segments. A 59-year-old man with a 3-month history of worsening chest pain and shortness of breath was referred to the pulmonary clinic. Chest computed tomography revealed low attenuation areas, suggesting emphysema, along with diffuse ground-glass opacities and interlobular septal thickening in both lungs. A transbronchial lung biopsy specimen revealed signet-ring cell carcinoma infiltrating the alveolar septa. Immunohistochemical staining of the cancer cells was positive for CDX-2, cytokeratin 7, and cytokeratin 20, and negative for surfactant apoprotein-A, TTF-1, and Napsin A. Gastrointestinal endoscopy revealed an ulcerative tumor in the stomach, and a biopsy from the tumor demonstrated malignant cells with similar morphology and immunophenotypes as those in the lungs. The final diagnosis was diffuse lung metastasis from gastric cancer. Our case shows that although multiple, well-defined nodules are typically considered to be the classic presentation of pulmonary metastasis, clinicians should also be aware of the possibility of pulmonary metastasis presenting as diffuse ground-glass opacities.

A case of a primary pulmonary meningioma mimicking a metastasis from a papillary thyroid carcinoma due to a size reduction after radioactive iodine therapy

Background

Primary pulmonary meningiomas (PPMs) are a rare mostly benign disease presenting as a solitary pulmonary nodule and are hardly distinguishable from a metastatic tumor because of a lack of specific radiological features. We described a case of a PPM initially diagnosed as a metastatic lung tumor from thyroid cancer with a size reduction after radioactive iodine therapy.

Case presentation

A 62-year-old woman who had undergone a total thyroidectomy for a papillary thyroid carcinoma 6 years prior presented with an enlarging pulmonary nodule. The nodule had decreased in size from 7.0 to 5.5 mm after adjuvant radioactive iodine therapy and enlarged to 8.7 mm over the next 5 years. Under a clinical diagnosis of a metastatic lung tumor, she underwent a thoracoscopic pulmonary wedge resection and was pathologically diagnosed with a PPM.

Conclusion

A surgical resection is required for histological diagnoses of PPMs especially in patients with a history of a malignancy.

Differences in PD-L1 expression on tumor and immune cells between lung metastases and corresponding primary tumors

BACKGROUND

It has been reported that the tumor microenvironment, including tumor-associated immune cells (ICs) and programmed cell death-ligand 1 (PD-L1) expression, differs between primary and metastatic tumors. This study aimed to elucidate the differences in PD-L1 expression on tumor cells (TCs) and ICs between lung metastases and corresponding primary tumors.

METHODS

We analyzed paired lesions from 44 patients diagnosed with lung metastases between 2005 and 2017 at Kyushu University. The percentages of PD-L1-positive TCs and ICs in lung metastases and the primary tumor were classified into five categories (0: <1%; 1: 1%-4%; 2: 5%-9%; 3: 10%-49%; and 4: ≥50%). Lesions in which ≥1% of the TCs and ICs were PD-L1-positive were considered positive.

RESULTS

The primary cancers included rectal (n = 19), colon (n = 10), liver (n = 10), bile duct (n = 2), stomach (n = 1), gall bladder (n = 1) and breast (n = 1). Discrepancies in PD-L1 expression on TCs and ICs between lung metastases and primary lesions were observed in 5 (11.4%, κ = 0.23) and 9 (20.5%, κ = 0.11) of the 44 cases, respectively. PD-L1 expression on ICs was higher in lung metastases than paired primary tumors (p = 0.026), although the percentage of PD-L1-positive TCs was not significantly different between lung metastases and primary tumors (p = 0.767).

CONCLUSIONS

There were significant differences in PD-L1 expression on TCs and ICs between lung metastases and primary tumors. Clinicians should be aware of these differences in the tumor microenvironment when treating patients with immunotherapy.

Venous phase contrast-enhanced computed tomography facilitates the detection of pulmonary venous tumor thrombus

A 64-year-old woman, with a history of hepatocellular carcinoma, developed recurrent metastatic lung nodules after lung metastasectomy 10 years ago. Computed tomography (CT) revealed tumors in the right middle, and left lower lobes. We planned a right middle lobectomy. Before operating, a contrast-enhanced CT in the pulmonary venous phase revealed a tumor in the pulmonary vein resembling a thrombus, indicating that the CT failed to facilitate accurate diagnosis. Following venous clamping and incision, the intravenous polypoid mass was surgically removed. As contrast-enhanced CT focuses on pulmonary arterial phases and might not detect venous lesions, we highlight the usefulness of venous phase contrast-enhanced CT for detecting pulmonary venous tumor thrombosis. Large lung metastatic carcinomas with venous extension may embolize to distant organs. Therefore, venous phase contrast-enhancement is essential for preoperative assessments of large or persisting metastatic lung tumors.

A case report of successful diagnosis of a pulmonary nodule by a survey of oncogenic mutations; primary lung carcinoma or pulmonary metastasis?

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It is very difficult to make a differential diagnosis between primary and metastatic lung carcinoma.

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The NRAS mutation is detected in several tumors, but the sites and the amino changes of NRAS mutaion is various.

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Examination of oncogenic mutation is a useful in the diagnosis of pulmonary tumors.

Introduction

The number of patients diagnosed with solid carcinomas is increasing, and the most common site of metastasis is the lungs. It is often difficult to make a differential diagnosis between primary lung carcinoma and metastatic lung tumor in using histological examination and by determining their immunohistological status.

Presentation

A 64-years-old man presented with dyspnea with chest computed tomography (CT) findings of a pulmonary tumor, and afterwards suffered from a sudden bowel hemorrhaged due to colorectal carcinoma. The histological diagnosis of a pulmonary tumor was poorly differentiated adenocarcinoma. Both Thyroid transcription factor-1 (TTF-1) and Cytokeratin20 (CK20) were immunohistologically negative. Of the some oncogenic mutations investigated, a neuroblastoma RAS viral oncogen homolog (NRAS) codon13 G13D mutation was detected in both the colorectal carcinoma and the pulmonary tumor tissue samples. Based on the result, the pulmonary tumor was diagnosed as a metastasis derived from colorectal carcinoma.

Discussion

Recently, examination of the oncogenes of solid carcinomas has been clinically investigated in primary lung caricnoma and in colorectal carcinomas. The clinical advantage of the oncogenic mutation survey is to identify the site, and the type, of amino acid change in detail. This case is a rare successful case of a survey of the oncogenes for giving a differential diagnosis.

Conclusion

A survey of the oncogenic genes is very useful to make a differential diagnosis between primary lung carcinoma and metastatic lung tumor.