Elastofibroma Dorsi: Causes, Symptoms, Diagnosis, and Treatment

What is Elastofibroma dorsi?

Elastofibroma dorsi, also simply known as elastofibroma, is a rare, slow-growing benign tumor (non-cancerous growth) that arises in the deep soft tissues of the back, specifically beneath the scapula (shoulder blade). The term itself is descriptive: elasto refers to the elastic fibers that characterize its microscopic appearance, fibroma denotes a fibrous tumor, and dorsi is Latin for “of the back”.

This tumor most commonly develops in the subscapular region, which is the area located below and behind the scapula. The scapula is the flat, roughly triangular bone that forms the posterior component of the shoulder girdle. It connects the upper arm bone (humerus) with the collarbone (clavicle) and provides attachment points for many muscles of the shoulder and upper back. The elastofibroma grows in the deep tissue between the lower pole of the scapula and the chest wall, embedded within or beneath the serratus anterior and rhomboid muscles.

Several demographic and clinical features characterize this condition:

• It occurs predominantly in older adults, most commonly in individuals over the age of 50
• It shows a marked female predominance, with women diagnosed far more frequently than men
• It is often bilateral, present on both sides of the back simultaneously, in a significant proportion of patients. Estimates suggest this occurs in one in three to as many as two in three patients
• It grows very slowly, typically over years, and often goes unnoticed until it reaches a size sufficient to cause symptoms or be detected incidentally during imaging performed for other reasons
• It is deeply located beneath the skin, developing within the muscular and fascial layers of the back rather than in the superficial subcutaneous tissue

Clinically, patients most commonly notice or are told about a firm, deep-seated mass in the lower angle of the scapular region. This mass may or may not be associated with discomfort or movement-related symptoms (discussed in detail below).

Importantly, elastofibroma dorsi has no malignant potential. It does not undergo cancerous transformation, and it cannot produce metastases. In other words, it cannot spread to distant organs or lymph nodes. While surgical removal is the primary treatment option when intervention is required, the prognosis is excellent. No fatal outcomes attributable to elastofibroma dorsi are documented in the medical literature.

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Causes

The precise etiology of elastofibroma dorsi, or the biological mechanism behind its development, remains incompletely understood. Since its first description in the medical literature by Järvi and Saxén in 1961, researchers have proposed several explanations for its origins, but none has been definitively proven.

Who Is Most Affected?

Elastofibroma dorsi is observed almost exclusively in patients in the fifth decade of life or older, with the peak incidence in the sixth and seventh decades. The strong female predilection suggests that hormonal or constitutional factors may play a role, though these have not been clearly elucidated.

The tumor appears to be more prevalent in the Japanese population compared to Western populations, suggesting that genetic or ethnic factors influence susceptibility. Some studies conducted in Japan have found relatively higher rates of incidental detection during imaging or autopsy series, raising the possibility that the condition may be underdiagnosed in other populations.

Theories About the Underlying Cause

Genetic Predisposition

There is meaningful evidence supporting a hereditary or genetic component in the development of elastofibroma dorsi. Family clustering of cases has been reported, and cytogenetic studies have identified abnormalities involving chromosome 1 in some tumor samples. However, the specific gene or genes involved have not been definitively characterized. This genetic susceptibility may explain why some individuals develop the tumor while others with apparently similar mechanical or lifestyle exposures do not.

Repetitive Mechanical Trauma

One of the most widely discussed (though not universally accepted) theories proposes that repetitive mechanical stress or friction between the lower pole of the scapula and the chest wall may trigger a reactive proliferation of fibrous and elastic connective tissue, eventually leading to the formation of an elastofibroma.

Several observations lend some support to this hypothesis: The tumor almost always develops at the same anatomical location, specifically the inferior angle of the scapula. This is where mechanical friction between the scapula and the posterolateral chest wall is greatest during arm movement.

• The condition is somewhat more common on the right side of the body, which may reflect the greater mechanical use of the dominant arm in most right-handed individuals
• Some early case reports described the condition in individuals engaged in heavy manual labor involving repetitive overhead arm movements

However, this theory remains controversial and not fully supported by the available evidence. Many patients with elastofibroma dorsi have no history of unusual mechanical stress or heavy manual labor, and the extremely consistent anatomical localization of the tumor may reflect a specific tissue vulnerability at that site rather than purely mechanical causation.

Reactive vs. Neoplastic Nature

There is ongoing debate in the pathological literature about whether elastofibroma dorsi is a true neoplasm (an autonomous clonal proliferation of cells) or a reactive lesion (an exaggerated tissue response to external stimuli). Some pathologists classify it as a pseudotumor or reactive fibroproliferative lesion rather than a true tumor, though in clinical practice this distinction has limited practical significance for patient management.

Age-Related Elastic Fiber Degeneration

Another proposed mechanism involves age-related abnormalities in elastic fiber metabolism. The characteristic microscopic appearance of elastofibroma, which includes degenerated and fragmented elastic fibers mixed with collagen and mature fat cells, may reflect an abnormal accumulation of dysfunctional elastic material. This process could occur in genetically susceptible individuals and might be worsened by local mechanical stress.

Summary of Risk Factors

While no definitive causal pathway has been established, the following factors are associated with an increased likelihood of developing elastofibroma dorsi:

• Advanced age (typically over 50 years)
• Female sex
• Family history of elastofibroma dorsi
• Possible genetic predisposition (chromosome 1 abnormalities)
• Possibly repetitive mechanical stress to the subscapular region, though this remains debated
• Japanese or East Asian ethnic background (higher prevalence reported)

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Symptoms

One of the clinically important aspects of elastofibroma dorsi is that it is frequently asymptomatic. Many patients have no complaints at all and often remain unaware of the tumor’s presence until it is discovered incidentally. This typically occurs during imaging performed for an unrelated reason, such as a chest CT scan for respiratory symptoms or a cardiac evaluation.

When symptoms do occur, they are typically mild to moderate in severity and are directly related to the mass and its effects on surrounding structures. The most commonly reported symptoms include:

Palpable Mass

The most frequent presentation occurs when either the patient or a clinician notices the tumor. This typically involves the sensation or detection of a firm, deep-seated lump in the lower angle of the scapular region. Because the tumor is located deep beneath the skin, within the muscular planes of the back, it may not be immediately visible but can often be felt as a distinct solid mass when the examiner’s fingers are pressed firmly into the subscapular area. The mass is typically:

• Firm to hard in consistency
• Non-tender (painless on palpation in many cases)
• Fixed or only slightly mobile, given its deep location between bony and muscular structures
• Slow-growing: patients may notice the mass has been present and stable for months or years
• Variable in size, ranging from a few centimeters to over 10 centimeters in the largest reported cases

Pain and Discomfort

While many patients are asymptomatic, a proportion experience pain or discomfort in the subscapular or periscapular area. This pain may be:

• Dull and aching, worsening with prolonged sitting, certain postures, or activities involving movement of the shoulder and arm
• Intermittent or positional: symptoms that are more noticeable in certain positions or after physical activity
• Radiating in some cases to the shoulder or upper arm, particularly if the mass is large enough to cause traction on adjacent structures

Scapular Snapping and Movement Abnormalities

A particularly characteristic symptom of elastofibroma dorsi is a phenomenon called “snapping scapula” or “winging scapula” though this symptom is not universally present. It involves the following:

• An audible or palpable snapping or clicking sensation may occur when the scapula moves over the chest wall during arm elevation or shoulder rotation. This happens because the tumor is mechanically interposed between the scapula and the chest wall during movement
• A metallic or grinding sound (crepitus) accompanying shoulder movement in some patients
• Limited range of motion of the shoulder or scapula, particularly during activities requiring raising the arm above the head or reaching behind the back
• A subjective sensation of tightness or restriction in the shoulder girdle

These mechanical symptoms can range from mildly annoying to significantly limiting, depending on the size and precise location of the tumor.

Bilateral Presentation

It is worth emphasizing that elastofibroma dorsi is bilateral in a substantial proportion of patients. Some sources estimate that between one-third and two-thirds of affected individuals have tumors on both sides of the back. However, the tumors may vary considerably in size between sides. In many cases, only the larger or more symptomatic side is initially identified, with the contralateral tumor discovered only during the diagnostic imaging workup.

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Diagnosis

Diagnosing elastofibroma dorsi requires a combination of clinical assessment, imaging studies, and, in most cases, histopathological confirmation through biopsy. The rarity of the condition and its imaging characteristics, which can closely resemble normal muscle, make diagnosis genuinely challenging even for experienced clinicians.

Clinical Assessment

The diagnostic process typically begins when a patient reports a palpable mass in the subscapular area, or when a clinician detects one during a physical examination. The location, consistency, size, and associated symptoms provide important diagnostic clues. A careful history can help raise or lower clinical suspicion for elastofibroma dorsi. This should include the patient’s age, sex, duration of the mass, and any family history of similar lesions.

Imaging Studies

Once a subscapular mass is identified or suspected, imaging is the next step in characterization. Different imaging modalities have varying diagnostic value for elastofibroma dorsi:

Plain X-Ray (Radiograph)

Plain radiographs of the chest or shoulder are generally of limited diagnostic value for elastofibroma dorsi. The tumor is composed of soft tissue and does not contain calcium deposits or other radiodense material that would make it visible on X-ray in most cases. Radiography may occasionally suggest a soft tissue mass by demonstrating subtle displacement of adjacent structures, but it cannot characterize the tumor meaningfully.

Ultrasound

Ultrasound can detect elastofibroma dorsi as a heterogeneous mass between the chest wall and the lower pole of the scapula, and may show alternating echogenic (bright) and hypoechoic (dark) bands corresponding to the interleaved fat and fibrous tissue of the tumor. However, ultrasound is operator-dependent and has limited specificity for elastofibroma dorsi. It cannot reliably distinguish this tumor from other soft tissue masses, and it provides less comprehensive anatomical detail than cross-sectional imaging.

Magnetic Resonance Imaging (MRI)

MRI is the imaging modality of choice for suspected elastofibroma dorsi. On MRI, the tumor typically displays a characteristic appearance:

• Isointense to muscle on T1-weighted sequences (similar signal to muscle) with interspersed areas of fat signal (high signal on T1)
• Heterogeneous signal on T2-weighted sequences, with alternating bands of low-signal fibrous tissue and high-signal fatty components
• A lenticular or crescent-shaped mass located between the inferior angle of the scapula and the chest wall
• No significant contrast enhancement with gadolinium, which reflects the predominantly fibrous and paucicellular nature of the tumor

This characteristic MRI appearance, particularly the interspersed fat signal within a fibromuscular mass at the typical location, is highly suggestive of elastofibroma dorsi. In many cases, it may allow for a confident radiological diagnosis. The bilateral nature of the tumor, when present, further supports the diagnosis.

CT Scan (Computed Tomography)

CT imaging can demonstrate elastofibroma dorsi as a heterogeneous soft tissue mass between the chest wall and scapula, with areas of fat attenuation interspersed within a predominantly soft tissue density lesion. However, CT is considered less sensitive and specific than MRI for characterizing this tumor and is generally reserved for patients in whom MRI is contraindicated (e.g., those with pacemakers or severe claustrophobia).

The Challenge of Diagnosis

An important clinical caveat must be acknowledged: because elastofibroma dorsi consists mainly of fibrous tissue, which has a density and MRI signal similar to normal skeletal muscle, and because it is a rare condition that many clinicians and radiologists are unfamiliar with, the diagnosis can be surprisingly challenging to establish confidently. The tumor may be underrecognized or misclassified, particularly when the radiologist is not specifically considering elastofibroma in the differential diagnosis.

Biopsy and Histopathological Confirmation

While MRI findings may be highly suggestive, definitive diagnosis of elastofibroma dorsi requires histopathological examination of tissue obtained by biopsy. This is important for several reasons:

1. To confirm the benign nature of the lesion: Ruling out malignancy is essential before deciding on a conservative management approach.
2. To avoid unnecessary or inappropriate surgery: If the lesion is not an elastofibroma but instead something else, such as a malignant soft tissue tumor, the surgical approach must be far more aggressive. This requires wider margins of resection.
3. To provide pathological certainty: In a location as surgically challenging as the subscapular region, avoiding surgery on a lesion that has not been histologically confirmed is prudent.

Microscopically, elastofibroma dorsi shows a characteristic but non-specific appearance: an abundance of thick collagen bundles interspersed with degenerated, fragmented, and beaded elastic fibers that have an unusual “serrated” or “globular” appearance, along with mature adipose (fat) tissue and occasional fibroblasts. Special stains for elastic fibers (such as Verhoeff-van Gieson stain) help highlight the abnormal elastin material.

Core needle biopsy, performed with a large-gauge needle under ultrasound or CT guidance, is the most commonly used technique for obtaining tissue from a deep subscapular mass. It is minimally invasive, can typically be performed as an outpatient procedure, and provides sufficient tissue for histopathological analysis in most cases.

Differential Diagnosis

Elastofibroma dorsi must be distinguished from other conditions that can present as a soft tissue mass in the subscapular or periscapular region, including:

• Lipoma: A benign tumor composed entirely of mature adipose tissue, appearing uniformly bright on T1-weighted MRI. Unlike elastofibroma, lipomas do not contain significant fibrous components and are typically homogeneous on imaging.
• Liposarcoma: A malignant tumor of adipose tissue that can have imaging features overlapping with elastofibroma, making biopsy particularly important in cases of diagnostic uncertainty
• Desmoid tumor (aggressive fibromatosis): A locally aggressive but non-metastasizing fibroblastic tumor that can occur in the soft tissues of the trunk
• Sarcoma: Various types of malignant soft tissue tumors (fibrosarcoma, undifferentiated pleomorphic sarcoma, synovial sarcoma) can arise in the periscapular region and must be excluded
• Fibromatosis: Benign but locally infiltrative proliferations of fibrous tissue
• Metastatic deposits: In patients with a known primary malignancy, soft tissue metastases must be considered
• Subscapular bursitis: Inflammatory conditions of the bursa between the scapula and chest wall can occasionally mimic the presentation of elastofibroma clinically

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Treatment

When Is Treatment Necessary?

Given the benign nature and typically indolent behavior of elastofibroma dorsi, treatment is not always required. Management decisions are individualized based on:

• The presence and severity of symptoms
• The size and rate of growth of the tumor
• The patient’s overall health status and fitness for surgery
• The patient’s preferences and concerns

For asymptomatic tumors that are incidentally discovered during imaging and confirmed to be elastofibroma by biopsy, a policy of watchful waiting (active surveillance) is entirely appropriate and widely recommended. Regular clinical and imaging follow-up, typically using MRI every one to two years, allows for monitoring of any changes in size or symptoms over time. The vast majority of elastofibromas remain stable for many years, and some may even remain unchanged indefinitely.

Remarkably, spontaneous complete regression has been documented in some cases, though this appears to be uncommon. The mechanism underlying spontaneous resolution is not understood.

Surgical Treatment

If treatment is required for reasons such as significant pain, functional limitation, rapid growth, cosmetic concerns, or diagnostic uncertainty, the standard approach is surgical excision. This involves the complete removal of the tumor through an open surgical procedure.

Indications for Surgery

• Symptomatic tumors: Significant pain, snapping scapula syndrome, or restriction of shoulder mobility that impairs daily activities or quality of life
• Large or growing tumors: Progressive enlargement that suggests a more active lesion or raises concern about the diagnosis
• Diagnostic uncertainty: When biopsy results are inconclusive and malignancy cannot be confidently excluded
• Patient preference: Some patients, even with asymptomatic tumors, prefer definitive surgical removal once the diagnosis is established

The Surgical Approach

Surgical excision of elastofibroma dorsi typically involves open surgery via a posterior approach to the subscapular region. The surgeon must navigate through multiple layers of muscle and fascia to reach the tumor, which is often densely adherent to the chest wall, the inferior angle of the scapula, and the surrounding musculature. This anatomical complexity is one reason why the surgery carries a relatively higher risk of complications compared to excision of more superficial soft tissue tumors.

Potential surgical complications include:

• Seroma (fluid collection in the surgical site) is one of the most common post-operative complications
• Wound infection
• Hematoma (blood collection)
• Injury to the long thoracic nerve, which supplies the serratus anterior muscle, can result in winging of the scapula
• Injury to the thoracodorsal nerve or vessels
• Incomplete resection: Because the tumor is often adherent, achieving complete margins can be challenging. Residual tumor may then contribute to recurrence

Risk of Recurrence

Elastofibroma dorsi can recur after surgical excision, particularly if the resection is incomplete. However, because the tumor is benign, recurrence does not imply malignant transformation. Instead, it simply means that residual tumor tissue has regrown over time. The decision to re-operate on a recurrent tumor must weigh the symptoms and impact on quality of life against the risks of repeat surgery.

Non-Surgical Management

For patients who are not surgical candidates (due to advanced age, significant comorbidities, or personal preference) or for those with mild symptoms that do not significantly impair function, non-surgical symptomatic management may be appropriate:

• Physical therapy: Exercises targeting the shoulder girdle musculature and periscapular stabilizers may help reduce mechanical symptoms and improve range of motion
• Analgesic medications: Non-steroidal anti-inflammatory drugs (NSAIDs) or acetaminophen may provide pain relief
• Activity modification: Avoiding specific movements or activities that provoke symptoms

There is no established pharmacological therapy that induces regression of elastofibroma, and radiation therapy has no role in the management of this benign condition.

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Prognosis and Long-Term Outlook

The prognosis for elastofibroma dorsi is excellent. Key prognostic points include:

• No malignant potential: Elastofibroma dorsi does not undergo malignant transformation and cannot produce metastases. It is unequivocally a benign condition.
• No known fatal outcomes: No deaths attributable to elastofibroma dorsi itself are documented in the peer-reviewed medical literature.
• High rates of symptomatic improvement after surgery: Most patients who undergo surgical excision for symptomatic elastofibroma experience significant or complete relief of their symptoms.
• Possible recurrence after surgery: Incomplete excision may be followed by tumor regrowth, but this remains a benign process.
• Stability of untreated tumors: Many elastofibromas remain stable in size and symptoms for many years without treatment, and some may spontaneously regress.

The principal concerns in the long-term management of elastofibroma dorsi are therefore not oncological (cancer-related) but instead functional and symptomatic. The focus is on ensuring the tumor does not cause unacceptable pain, movement restriction, or cosmetic distress. Additionally, when surgical intervention is necessary, it should be performed safely with an acceptable risk-benefit balance.

Follow-Up After Diagnosis

For patients managed conservatively (without surgery), periodic follow-up with clinical examination and imaging is appropriate to:

• Monitor for any significant change in size
• Assess for development or worsening of symptoms
• Confirm the stability of the diagnosis

Because elastofibroma is a benign tumor with no malignant potential, intensive oncological surveillance is not required. The follow-up schedule can be individualized based on the patient’s situation, typically involving an MRI every one to two years in the early period following diagnosis, with less frequent imaging if the tumor remains stable.

For patients who have undergone surgical excision, follow-up focuses primarily on monitoring for recurrence, which typically becomes apparent within the first few years after surgery.

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Elastofibroma Dorsi vs. Other Soft Tissue Tumors

To help patients understand where elastofibroma dorsi fits within the broader landscape of soft tissue tumors, it is useful to compare it with some related conditions:

This comparison highlights why biopsy plays such a critical role in the diagnostic process. The imaging findings of these conditions often appear similar, so confirming the histological diagnosis is essential for treatment planning and determining prognosis.

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Living with Elastofibroma Dorsi

For many patients, receiving a diagnosis of elastofibroma dorsi brings significant relief, especially after a period of anxiety about an undiagnosed mass. Understanding that the condition is benign, non-cancerous, and generally not life-threatening allows patients to approach management decisions with a clearer perspective.

Here are some practical considerations for patients living with elastofibroma dorsi:

Monitoring Your Symptoms

Keep track of any changes in your symptoms. Pay special attention to new or worsening pain, changes in the size of the mass you can feel, any new restriction in shoulder movement, or any new symptoms on the opposite side of the back. Report these changes to your doctor promptly, as they may warrant repeat imaging.

Understanding Bilateral Disease

If you have been told that you have elastofibroma dorsi on one side, be aware that a significant proportion of patients have bilateral tumors. Ask your doctor whether imaging of the opposite side has been performed or is recommended. Finding a second tumor on the other side is not necessarily alarming. This finding aligns with the known bilateral nature of this condition in many patients. However, it remains important information for your clinical team.

Discussing Surgery Carefully

If your doctor recommends surgical excision, take the time to discuss the procedure thoroughly, including:

• What type of anesthesia will be used
• What the expected recovery time is
• What the risks and potential complications are
• What happens if the tumor recurs after surgery
• Whether watchful waiting might be an equally reasonable option in your specific case

Surgery for elastofibroma dorsi is generally not urgent. In most cases, there is time to seek a second opinion, consult with a specialized orthopedic or thoracic surgeon with experience in this type of procedure, and make an informed decision.

Emotional and Psychological Wellbeing

Even when a diagnosis is confirmed as benign, the experience of discovering a tumor and navigating the diagnostic process can be emotionally challenging. Feelings of anxiety, uncertainty, and concern are natural. If you find that worry about your condition is significantly affecting your quality of life, speaking with your doctor, a counselor, or a patient support network can be genuinely helpful.

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Frequently Asked Questions

Is elastofibroma dorsi cancer?

No. Elastofibroma dorsi is a benign tumor, meaning it is not cancer. It has no capacity to spread to lymph nodes or other organs (no metastatic potential) and does not undergo malignant transformation. The prognosis is excellent.

Can elastofibroma dorsi go away on its own?

In some documented cases, spontaneous complete regression of elastofibroma dorsi has been observed without any treatment. However, this appears to be uncommon. Most untreated tumors remain stable in size for many years.

Does elastofibroma dorsi always need to be removed?

No. Surgical removal is not always necessary. For asymptomatic tumors that have been confirmed by biopsy to be elastofibroma, a policy of watchful waiting with periodic imaging follow-up is entirely appropriate and widely practiced. Surgery is generally recommended when the tumor causes significant pain, functional limitation, or when diagnostic uncertainty cannot be resolved conservatively.

Can elastofibroma dorsi come back after surgery?

Yes, recurrence is possible, particularly if the surgical excision is incomplete. However, any recurrence remains a benign process, and the decision to re-operate must weigh the benefits against the risks of repeat surgery.

Is elastofibroma dorsi hereditary?

There is evidence of familial clustering and possible genetic susceptibility involving chromosome 1, suggesting a hereditary component in some cases. If you have a first-degree relative with elastofibroma dorsi, it is worth mentioning this to your doctor.

Can both sides be affected at the same time?

Yes. Bilateral involvement, meaning tumors on both sides of the back, occurs in a significant proportion of patients. This affects roughly one-third to two-thirds of those diagnosed. The tumors may differ in size between sides, and one may be asymptomatic while the other causes symptoms.

What kind of doctor should I see for elastofibroma dorsi?

Depending on the clinical situation, relevant specialists may include:

• An orthopedic surgeon with experience in soft tissue tumors or shoulder surgery
• A thoracic surgeon if the chest wall is significantly involved
• A radiologist specializing in musculoskeletal imaging for MRI interpretation
• A pathologist for biopsy interpretation
• An oncologist (specifically a sarcoma specialist) if there is any diagnostic uncertainty about malignancy

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Sources and Bibliography

• Elastofibroma: An Uncommon Tumor Revisited – Rashmi Patnayak, Amitabh Jena, Sarla Settipalli, and N Nagesh. NCBI PMC.
• Medscape – Elastofibroma Overview
• Chest Wall Tumors – Tushar Bajaj; Ayham Aboeed. StatPearls, NCBI Bookshelf.
• Järvi OH, Saxén AE. Elastofibroma dorsi. Acta Pathol Microbiol Scand Suppl. 1961;51(Suppl 144):83–84.
• Brandser EA, et al. Elastofibroma dorsi: prevalence in an elderly patient population as revealed by CT. AJR Am J Roentgenol. 1998;171(4):977–980.
• Muramatsu K, et al. Elastofibroma dorsi: diagnosis and treatment. J Shoulder Elbow Surg. 2007;16(5):591–595.
• Nishio J, et al. Elastofibroma dorsi: new observations on clonal karyotypic abnormalities. Cancer Genet Cytogenet. 2002;139(2):166–169.
• Daigeler A, et al. Elastofibroma dorsi, a rare benign pseudotumor, is typically found in the body. Eur J Med Res. 2007;12(3):131–136.