
==== Front
Respirol Case Rep
Respirol Case Rep
10.1002/(ISSN)2051-3380
RCR2
Respirology Case Reports
2051-3380
John Wiley & Sons, Ltd Chichester, UK

10.1002/rcr2.70028
RCR270028
Case Report
Case Report
Pulmonary Langerhans cell histiocytosis with multiple cavitary nodules after lung cancer surgery
PULMONARY LANGERHANS CELL HISTIOCYTOSIS
Sugihara et al.
Sugihara Minoru https://orcid.org/0009-0006-3949-8928
1 sugihara.minoru522@gmail.com

Okamoto Sawako 1
Taniguchi Tetsuo 1
1 Department of Thoracic Surgery Komaki City Hospital Komaki Japan
* Correspondence
Minoru Sugihara, Department of Thoracic Surgery, Komaki City Hospital, 1‐20, Jobushi, Komaki, Aichi 485‐8520, Japan.
Email: sugihara.minoru522@gmail.com

18 9 2024
9 2024
12 9 10.1002/rcr2.v12.9 e7002812 8 2024
11 9 2024
© 2024 The Author(s). Respirology Case Reports published by John Wiley & Sons Australia, Ltd on behalf of The Asian Pacific Society of Respirology.
https://creativecommons.org/licenses/by-nc-nd/4.0/ This is an open access article under the terms of the http://creativecommons.org/licenses/by-nc-nd/4.0/ License, which permits use and distribution in any medium, provided the original work is properly cited, the use is non‐commercial and no modifications or adaptations are made.

Abstract

Pulmonary Langerhans cell histiocytosis (PLCH) is a subtype of Langerhans cell histiocytosis, a rare neoplastic disease characterized by lung involvement. Here, we present a case involving a patient with multiple cavitary nodules who was diagnosed with PLCH during surveillance after lung cancer surgery. A 74‐year‐old woman underwent right upper lobe resection surgery for right upper lobe lung adenocarcinoma, pStage IIA, 5 years ago. The patient underwent surveillance without adjuvant chemotherapy. During the fifth year of follow‐up, multiple nodules with cavitation were observed on computed tomography in both lung fields. Chemotherapy was considered to address the suspected recurrence of lung cancer; however, video‐assisted thoracoscopic surgery was performed due to the need for biomarker testing. Pathological examination led to the diagnosis of PLCH. This case emphasizes the importance of a proactive histological diagnosis to determine the appropriate treatment strategy, even in situations where lung cancer recurrence is clinically suspected.

Pulmonary Langerhans cell histiocytosis is a subtype of Langerhans cell histiocytosis, a rare neoplastic disease characterized by lung involvement. We report a case of Pulmonary Langerhans cell histiocytosis that was diagnosed through the detection of multiple cavitary nodules in both lung fields during surveillance after lung cancer surgery.

lung cancer
multiple pulmonary nodules
pulmonary Langerhans cell histiocytosis
source-schema-version-number2.0
cover-dateSeptember 2024
details-of-publishers-convertorConverter:WILEY_ML3GV2_TO_JATSPMC version:6.4.8 mode:remove_FC converted:19.09.2024
Sugihara M , Okamoto S , Taniguchi T . Pulmonary Langerhans cell histiocytosis with multiple cavitary nodules after lung cancer surgery. Respirology Case Reports. 2024;12 (9 ):e70028. 10.1002/rcr2.70028

Associate Editor: Diego Castillo Villegas
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pmcINTRODUCTION

Pulmonary Langerhans cell histiocytosis (PLCH), a subtype of Langerhans cell histiocytosis (LCH), is a rare neoplastic disease characterized by the clonal proliferation of precursor cells in the bone marrow, leading to lesions in various organs. PLCH typically presents with respiratory symptoms in young smokers, with the distinctive presence of multiple nodules with cystic changes in both lung fields. Here, we report a case of PLCH that was diagnosed through the detection of multiple cavitary nodules in both lung fields during surveillance after lung cancer surgery.

CASE REPORT

The patient was a 74‐year‐old woman with a smoking history of half a pack per day for 55 years. Five years prior, she underwent right upper lobe resection for invasive, solid‐predominant, pT2bN0M0 Stage IIA (8th edition of the TNM classification of lung cancer) lung adenocarcinoma. The patient underwent surveillance without adjuvant chemotherapy and had remained recurrence free. She did not stop smoking after the surgery.

During the postoperative fifth‐year follow‐up, computed tomography (CT) revealed multiple nodules, with a maximum diameter of 10 mm, in both lung fields (Figure 1). Some of these nodules contained thin‐walled cavities, predominantly in the lower lobes.

Positron emission tomography‐CT revealed nodules in the lung fields with a mix of 18F‐fluorodeoxyglucose‐avid and non‐avid lesions, and a maximum standardized uptake value (SUVmax) of 8.6 (Figure 1). 18F‐fluorodeoxyglucose uptake was also observed in the liver. Blood tests revealed no signs of inflammation or elevated levels of tumour markers related to lung carcinoma.

FIGURE 1 Imaging findings. Computed tomography (CT) reveals multiple nodules in both lung fields. Some nodules contain thin‐walled cavities. Positron emission tomography‐CT reveals nodules in the lung fields with a mix of 18F‐fluorodeoxyglucose‐avid and non‐avid lesions. Asterisks indicate nodules resected during surgery.

Recurrence of multiple metastatic lung cancer and liver metastases was suspected, and chemotherapy was considered; however, surgical biopsy was scheduled for biomarker testing. Video‐assisted thoracoscopic surgery revealed palpable nodules with elastic consistency. Three nodules identified in the right lower lobe were biopsied via wedge resection.

Macroscopically, the resected specimens showed nodules with a maximum diameter of 8 mm that were uniformly white without cavitation, with clear borders and smooth edges (Figure 2). Pathologically, clustered histiocytes with a coffee‐bean nuclear groove were observed with eosinophilic infiltration in the fibrous stroma. The histiocytes were positive for S‐100 and CD1a, confirming PLCH (Figure 3). To rule out mycobacterium infection or bacteremic embolism, a bacterial culture test was performed, which yielded negative results.

FIGURE 2 Macroscopic findings. Resected specimens show uniform white nodules without cavitation.

FIGURE 3 Pathological findings. Clustered histiocytes with a coffee‐bean nuclear groove (long arrow) are observed, with eosinophilic infiltration (short arrow) in the fibrous stroma (haematoxylin–eosin stain[A]). Histiocytes are positive for S‐100 [B] and CD1a [C].

Smoking cessation was strongly advised, and a reduction in the size of multiple nodules was observed on CT 2 months later (Figure 4). Regarding the liver lesions, while the possibility of LCH‐related hepatic involvement could not be ruled out, an imaging follow‐up plan was chosen considering the high risk of biopsy.

FIGURE 4 Computed tomography findings. A reduction in the size of multiple nodules is observed on computed tomography (CT) 2 months after smoking cessation. *A‐1 to A‐3: CT before smoking cessation; B‐1 to B‐3: CT 2 months after smoking cessation.

DISCUSSION

PLCH can occur either as part of a multisystem LCH or as a lesion in a single‐system LCH (single‐system PLCH). Single‐system PLCH is strongly associated with a smoking history in >90% of patients and is prevalent among young adults aged 20–40 years. Initially, PLCH was considered an inflammatory or reactive disorder because of its strong association with smoking. However, PLCH is currently recognized as a neoplastic disorder involving clonal proliferation, supported by the identification of MAPK signalling pathway alterations in 85% of single‐system PLCH cases.

PLCH shows multiple centrilobular nodules in both lung fields, with a predominance in the apical and middle lobes. These nodules often progress to those with cystic changes, which can sometimes merge with each other. 1 , 2 The differential diagnosis for these multiple nodules with cystic changes include silicosis, sarcoidosis, granulomatosis with polyangiitis, lung cancer, metastatic lung tumour, mycobacterium infection, bacteremic pulmonary embolism, pneumocystis pneumonia, and others. Although diagnosis is possible through bronchoscopy, the diagnostic yield is low, ranging from 15% to 40%. Therefore, diagnosis using surgical lung biopsy is recommended. 1

Pathologically, PLCH is characterized by the neoplastic clonal proliferation of Langerhans cells, which are large round or oval cells with coffee‐bean‐shaped nuclei expressing CD1a and S‐100. Additionally, there is an infiltration of inflammatory cells, such as eosinophils.

Smoking cessation is critical for the stabilization and improvement of PLCH symptoms. For severe cases and those that progress despite smoking cessation, and for patients with multisystem LCH, systemic therapies, such as cladribine or BRAF/MEK inhibitors, are recommended.

In this case, multiple cavitary nodules were observed on CT during the fifth‐year follow‐up after lung cancer surgery. Although recurrence was suspected based on imaging, biopsy was performed due to the possibility of various differential diagnoses, as mentioned previously, and the need for biomarker testing before initiating chemotherapy. This led to the diagnosis of PLCH. Given the patient's advanced age and atypical predominance of lesions in the lower lobes, this case was unusual.

Although its associations with other malignancies, such as lung cancer, have been reported, 3 , 4 there has been only one reported case of PLCH requiring differentiation from recurrence after surgery 5 ; this case represents the second reported case. Even when lung cancer recurrence is suspected based on imaging, obtaining a definitive diagnosis through pathological tissue examination is crucial for determining the appropriate treatment.

This report discusses a rare case of PLCH during surveillance after lung cancer surgery and emphasizes the importance of a proactive histological diagnosis to determine an appropriate treatment strategy, even in situations where lung cancer recurrence is clinically suspected.

AUTHOR CONTRIBUTIONS

Minoru Sugihara wrote the article. Minoru Sugihara and Tetsuo Taniguchi performed the surgical procedure. Sawako Okamoto discussed the content of the manuscript. Tetsuo Taniguchi supervised the editing of the manuscript. All authors read and approved the final manuscript.

FUNDING INFORMATION

This study received no funding.

CONFLICT OF INTEREST STATEMENT

None declared.

ETHICS STATEMENT

The authors declare that appropriate written informed consent was obtained for the publication of this manuscript and accompanying images.

ACKNOWLEDGMENTS

We would like to thank Editage (www.editage.jp) for English language editing.

This case was presented as an abstract at the 39th Annual Meeting of the Japanese Association for Chest Surgery.

DATA AVAILABILITY STATEMENT

Data sharing not applicable to this article as no datasets were generated or analysed during the current study.
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