A 60-year-old gentleman was referred via his GP for a chest x-ray for left lower chest wall pain. Initial chest radiograph demonstrated a small pulmonary nodule within the left mid-zone. Before any further investigations were performed a repeat chest x-ray was performed two months later for persisting chest wall pain. This again demonstrated a left mid-zone pulmonary nodule however at this stage an approximately 2cm expansile lytic focus was seen within the right scapula, which had not been reported on previous imaging. Margins were well defined and there was no periosteal reaction.
Patient proceeded to CT chest.
CT chest demonstrated multiple left-sided lung nodules and appearances within the left scapula revealed the lytic lesion to be lobulated, expansile, peripherally sclerotic, predominantly lucent with mineralised architecture centrally and cortical breach anteriorly. Additional lucent and peripherally sclerotic lesion was present within the left proximal humerus. No locally aggressive features however lesion was suspicious for further disease.
Myeloma screen and PSA were normal. CT abdomen and pelvis did not reveal any significant abnormality.
MRI of the right scapula demonstrated the expansile bone lesion without soft tissue mass or periosteal reaction. Signal was intermediate on T1 with heterogenous intermediate to high signal on fluid sensitive sequences, T2 and STIR.
Given the indeterminate features, the lesion underwent CT guided biopsy which confirmed the lesion as epithelioid haemangioendothelioma.
Subsequent bone scintigraphy demonstrated increased uptake within the right scapular and proximal humeral lesions confirming metastatic disease.
Epithelioid haemangioendothelioma is a rare vascular tumour that commonly arises within lung, liver and superficial soft tissues [1]. Epithelioid haemangioendotheliomas have a prevalence of less than one in a million and presentation of the bone is an extremely rare occurrence compromising less than 1% of bone tumours [2,3].
Epithelioid haemangioendothelioma was first described in 1982 and is considered a low to intermediate grade malignant vascular tumour. Intraosseous lesions are predominantly located within the tubular bones but can arise anywhere within the skeleton. It can be multifocal in up to 64%[4,5].
Case series consisting of 46 patients with an average follow-up of 46 months demonstrated a post-resection local recurrence rate of 13%, metastatic rate of 31% and a mortality rate of 13%[5].
The most common presentation is within the second decade of life [6]. It is usually non-specific in nature with bony pain or superficial tissue swelling. Rarely, they can present as a pathological fracture [7]. Examination is also non-specific may reveal a pale or red firm mass.
As well as Epithelioid haemangioendothelioma, there are other subtype of haemangioendotheliomas, namely kaposiform dapska tumour, spindle-cell, retiform and composite. They are vascular in nature and composed of epithelioid-appearing endothelial cells which are organised into cords and nests within myxoid or hyaline stroma[8]. The pathogenesis remains uncertain however recent cytogenetic studies demonstrate that the tumorigenesis is a result of gene mutations, which is useful in demonstrating that multifocal disease is a result from metastases, and not concurrent neoplastic proliferation [9].
They have a variable appearance at imaging depending on level of aggressiveness. Radiographically they are lytic in nature and may have a honeycomb appearance. They may be bubbly in nature and can show bony expansion. In aggressive cases they may show permeative destruction [10]. Internal calcification or matrix, as is seen is this case, is considered very rare findings [11]. The presence of multifocal lesions throughout the skeleton or in one anatomic region can be a clue to indicate a disease is of vascular origin [12].
MR findings show inhomogeneous low T1 and inhomogeneous higher T2 signal. They will be diffusely enhancing and can have prominent peripheral vessels.
They will have a wide differential including plasmacytoma or giant cell tumour if unifocal, as metastases, brown tumours and multiple myeloma if multifocal. However given their non-specific appearances they require histology to confirm their diagnosis [13].
The multiple lung nodules were considered metastatic in nature. Repeat CT chest performed after a 4 month interval showed no interval change in appearances of the pulmonary nodules or bony lesions. Following sarcoma MDT and review by the regional oncology service patient was managed conservatively. Unfortunately, follow up CT studies demonstrated disease progression.
Epithelioid haemangioendothelioma of the bone is a rare entity and no standard treatment options have been proposed. Radical surgery is performed for resectable tumours, solitary or multiple. Radiofrequency ablation has also been used pre-operatively to reduce the extent of resection and improve aesthetics and need for amputations [14].
Learning points
Epithelioid haemangioendothelioma
This work is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License.
Based on the provided X-ray, CT, and MRI images, the following observations can be noted:
• A small pulmonary nodule is seen in the middle zone of the left lung field.
• In the right scapula, there is a lytic lesion approximately 2 cm in diameter with clear margins, showing an expansile change and no obvious periosteal reaction. On CT, a local “radiolucent area” can be observed, and some internal components are relatively well-demarcated from normal bone.
• There are multiple small nodules in the lungs, with no significant progression in size or morphology (no remarkable changes in the imaging studies taken several months apart).
• MRI shows an uneven signal in the right scapular lesion, relatively low signal on T1, high signal on T2, and heterogeneous enhancement after contrast administration. Partial internal septations or calcifications can be observed in certain areas of the tumor.
Based on the patient’s age (60-year-old male), the expansile lytic lesion of the scapula, and the presence of multiple nodules in the lungs, potential diagnoses and differential diagnoses include:
1. Metastatic tumor (bone metastases): Multiple pulmonary nodules are common in metastatic malignancies; bone destruction is also consistent with metastatic lesions. However, in this case, the lesion has well-defined margins and some vascular features suggested histologically, so metastatic disease would still need to be confirmed through pathology.
2. Multiple myeloma or plasmacytoma: Myeloma can present with lytic bone lesions and pain. Patients may have chest wall pain, but multiple small nodules in the lungs are not the most typical presentation. Further tests such as serum protein electrophoresis, urine light chains, and bone marrow biopsy are required to rule it out.
3. Giant cell tumor: Commonly seen in long bones or vertebral bodies, presenting as localized lytic destruction and expansion, sometimes with well-defined borders. However, given its location in the scapula and the concurrent presence of lung nodules, it requires careful consideration.
4. Vascular tumors (e.g., angiosarcoma, epithelioid hemangioendothelioma, etc.): Epithelioid hemangioendothelioma is a low-to-intermediate malignant vascular tumor that can affect bone as well as the lungs, liver, and other organs, fitting the multifocal presentation in this case.
5. Other rare tumors or infectious lesions: For instance, tuberculosis or granulomatous disease, but the imaging findings and clinical course seem less suggestive of these.
Combining the pathological examination results (epithelioid hemangioendothelioma) with the characteristics of multiple lesions in this patient, the most likely diagnosis is:
Epithelioid Hemangioendothelioma, involving bone with suspected pulmonary nodular involvement (possible metastases).
According to current evidence and literature, epithelioid hemangioendothelioma is rare in bone. However, it characteristically presents as solitary or multifocal lytic lesions that can involve the lungs, liver, and other organs simultaneously or sequentially.
If uncertainty remains or the diagnosis cannot be fully confirmed by routine imaging, further tissue biopsy or advanced molecular/genetic testing can be performed to assist in clarifying the final diagnosis.
Treatment Strategies:
1. Surgical resection or lesion debridement: For bone lesions that can be completely resected or are relatively localized, surgical removal may be considered. If there are multiple lesions that cannot be completely removed, curettage, decompression, or other limb-/function-preserving procedures may be performed.
2. Interventional and other local treatments: Such as radiofrequency ablation, which can help reduce tumor volume, alleviate pain, and improve local function. These may be combined with neoadjuvant therapies to decrease the extent of surgery required.
3. Systemic therapy: Because epithelioid hemangioendothelioma has some malignant potential, especially when accompanied by lung involvement, an oncology team should evaluate whether chemotherapy, targeted therapy, or immunotherapy is indicated.
4. Regular follow-up: There is a risk of recurrence and metastasis, necessitating adequate and ongoing imaging and clinical evaluations.
Rehabilitation and Exercise Prescription:
1. Early Phase: Emphasize protective exercises. Recommended activities include range-of-motion exercises and light resistance training to avoid excessive stress that might cause pathological fractures in areas with bone lesions. Examples include assisted shoulder exercises (passive or with small weights) and breathing exercises (deep breathing, blowing up balloons, etc.) to improve pulmonary function and endurance.
2. Intermediate Phase: Once pain is controlled and the condition is stable, gradually increase core strength and upper limb muscle training, such as light resistance band exercises, stationary cycling, or elliptical aerobic workouts (3–4 times per week, 20–30 minutes each session). Increase intensity and duration gradually based on subjective fatigue and pain assessments.
3. Late and Maintenance Phase: If the condition remains well controlled, moderate-intensity exercises (such as light dumbbell training, swimming, etc.) can be introduced under professional guidance. Adopt the FITT-VP principles (Frequency, Intensity, Time, Type, Volume, Progression) to progressively increase training volume. During stable phases, exercise 3–5 times per week for 30–45 minutes per session, maintaining a safe load and closely monitoring local lesion response.
4. Individualization and Safety: For patients with significant bone destruction, severe pain, or poor pulmonary function, weight-bearing and high-impact exercises should be reduced. Carefully monitor for any discomfort. If severe pain, sudden difficulty breathing, or other acute symptoms occur, stop immediately and seek medical evaluation.
Disclaimer:
This report is a reference analysis only and is not intended as a definitive medical diagnosis or treatment guide. It should not replace in-person consultations or the advice of specialist physicians. If you have any concerns or changes in condition, please consult a specialist promptly.
Epithelioid haemangioendothelioma
