We present the case of a 79-year-old woman with multiple bilateral pulmonary nodules identified during an investigation for abdominal pain, initially suspected to represent metastatic disease. Extensive clinical, laboratory, and imaging workup failed to reveal a primary origin. After two non-diagnostic transthoracic biopsies, the patient underwent single-port video-assisted thoracoscopic surgery (VATS) with excision of two nodules from the upper and lower lobes of the right lung. Histopathological examination revealed an epithelioid hemangioendothelioma (EHE), a rare vascular neoplasm. This case illustrates the diagnostic process and pathological features of pulmonary EHE, with a brief clinical overview.

Accurate localization of nonpalpable pulmonary nodules is critical for successful surgical resection. This study aimed to evaluate the feasibility and safety of the watershed localization method (WALM), a technique that uses three-dimensional reconstruction and temporary occlusion of watershed arteries or veins combined with indocyanine green (ICG) fluorescence staining for real-time intraoperative navigation. Clinical data were collected from patients who underwent video-assisted thoracoscopic pulmonary wedge resection with arterial-WALM (A-WALM), venous-WALM (V-WALM), or CT-guided localization (CT-GL) from October 2023 to October 2025. Patients were divided into three groups according to the localization method. Perioperative data were compared to evaluate localization efficacy. Both A-WALM and V-WALM were associated with shorter localization procedure time, lower incidence of localization-related complications, and reduced total hospitalization costs as compared with CT-GL. However, they were associated with greater postoperative drainage volume and longer chest tube indwelling time, with no significant differences in other indicators. When the pulmonary fissure is completely developed, the A-WALM approach may be better suited for nodules located in the posterior segment of the right upper lobe, right middle lobe, apicoposterior segment of the left upper lobe, or dorsal and anteromedial basal segments of either lower lobe; V-WALM may be preferable for nodules located in the anterior and lingular segments of the left lung and the posterolateral basal segment of both lungs, while either A-WALM or V-WALM is suitable for nodules in the apical and anterior segments of the right upper lobe. When the pulmonary fissure is incompletely developed, V-WALM may be preferred for localizing nodules in the right middle lobe and apicoposterior segment of the left upper lobe. In conclusion, both A-WALM and V-WALM appear to be feasible intraoperative localization alternatives to CT-GL in selected patients with nonpalpable pulmonary nodules, although they are associated with increased postoperative drainage and longer chest tube duration.

Sarcoidosis is a multisystem granulomatous disease that can involve multiple organ systems, present with varied clinical features, and overlap diagnostically with malignancy and immune-mediated disorders. We report the case of a 39-year-old woman who presented with mild dyspnea, generalized weakness, and unintentional weight loss, accompanied by marked hypereosinophilia. Laboratory evaluation revealed a cholestatic pattern of liver injury, elevated total serum IgG, markedly elevated serum IgG4, elevated serum IgE, polyclonal hypergammaglobulinemia, and elevated serum angiotensin-converting enzyme levels. Cross-sectional imaging demonstrated marked hepatosplenomegaly with multiple nodular lesions, extensive abdominal and mediastinal lymphadenopathy, and bilateral subpleural pulmonary nodules. Given these findings, an infiltrative or malignant process was initially suspected. Excisional lymph node biopsy revealed non-necrotizing granulomatous inflammation consistent with sarcoidosis. Bone marrow aspiration and biopsy demonstrated preserved hematopoiesis without abnormal cellular infiltration, while acid-fast bacilli staining and mycobacterial cultures were negative, effectively excluding hematologic malignancy, tuberculosis, and primary hypereosinophilic syndromes. This case expands the limited literature on hepatic sarcoidosis presenting with marked hypereosinophilia and elevated serum IgG4, emphasizing the importance of histopathological confirmation and systematic exclusion of alternative diagnoses.

Intraplacental choriocarcinoma (ICC) is a rare gestational trophoblastic tumor that is often difficult to diagnose and is occasionally associated with fetomaternal hemorrhage (FMH). A 28-year-old woman presented with decreased fetal movements at 38 weeks of gestation. Due to a nonreassuring fetal heart rate pattern, an emergency cesarean section was performed. Severe neonatal anemia (3.2 g/dL) and markedly elevated maternal serum alpha-fetoprotein levels suggested FMH, despite normal maternal hemoglobin F levels. Initial placental pathology was unremarkable. Thirteen days postpartum, the patient developed massive vaginal bleeding requiring uterine artery embolization (UAE). Elevated serum β-hCG levels and multiple pulmonary nodules led to a clinical diagnosis of choriocarcinoma. Placental re-evaluation confirmed ICC. Chemotherapy with methotrexate, etoposide, and actinomycin D resulted in complete remission. In conclusion, ICC should be considered in cases of unexplained FMH or postpartum hemorrhage. UAE did not appear to impair the efficacy of subsequent chemotherapy in this case.

Background and Clinical Significance: Pulmonary crystal-storing histiocytosis (CSH) without an associated haematological malignancy, lymphoproliferative disorder, plasma cell disorder, or other identifiable underlying condition is exceptionally rare. Long-term radiological data from published cases remain limited, and this case, contextualised by a narrative review of the literature, may expand the recognised imaging spectrum of localised pulmonary CSH. Case Presentation: We report the case of a 59-year-old man with incidental multiple pulmonary lesions identified on CT thorax imaging. The lesions demonstrated an unusual combination of cystic change, cavitation, and surrounding ground-glass opacities. His medical history was significant for bipolar disorder treated with lithium and a 50-pack-year smoking history. Interval imaging showed progression, prompting further investigation and ultimately right upper lobectomy. Histopathological analysis confirmed pulmonary CSH; lesional cells contained crystalloid material and showed CD68 and PAS positivity, with dual kappa and lambda expression on immunohistochemistry. Markers for other differential diagnoses, including Congo red, birefringence, Langerin, and CD1a were negative. Following diagnosis and resection, serial imaging demonstrated fluctuating yet slowly progressive pulmonary abnormalities. No lymphoproliferative or plasma cell disorder has emerged after more than seven years of post-diagnostic surveillance and more than ten years since the initial imaging abnormality. Conclusions: This case demonstrates that the radiological spectrum of localised pulmonary CSH may include cystic, cavitary and ground-glass abnormalities, with subsequent fluctuating yet slowly progressive post-resection evolution. Pulmonary CSH should be considered in the differential diagnosis of unexplained or atypical pulmonary nodules, particularly when histiocyte-rich pathology with intracytoplasmic crystalloid material is identified. Long-term multidisciplinary surveillance is warranted.

Pulmonary neuroendocrine tumors are uncommon malignancies, and cutaneous metastasis as the initial presentation is exceedingly rare, often leading to diagnostic delays due to nonspecific clinical features. We reported a case of a 57-year-old male presenting with multiple progressively enlarging, painless cutaneous and subcutaneous nodules on the scalp and left chin without accompanying respiratory and constitutional symptoms. The lesions were initially treated as benign dermatological conditions without improvement. Excisional biopsy of a chin lesion demonstrated dermal infiltration by atypical polygonal cells with neuroendocrine morphology and dermal lymphatic invasion. Immunohistochemistry showed positivity for synaptophysin, cytokeratin 7 (CK7), and Cam5.2, consistent with neuroendocrine carcinoma. Contrast-enhanced computed tomography identified a heterogeneously enhancing mass in the left lower lobe of the lung with widespread metastatic disease. Further evaluation with Gallium-68 DOTATATE positron emission tomography/computed tomography, a somatostatin receptor-targeted imaging study, demonstrated avid lesions in the lung, lymph nodes, subcutaneous tissue, omentum, and skeleton. The patient was treated initially with octreotide hormone therapy. The patient had disease progression; therefore, therapy was changed to carboplatin and etoposide. This case highlights that unexplained skin lesions may present as the initial manifestation of an underlying visceral malignancy, signifying the role of early biopsy and comprehensive imaging to enable timely diagnosis and management of aggressive pulmonary neuroendocrine tumors.