What Is Nodular Fasciitis?

Introduction

Nodular fasciitis is an uncommon benign soft tissue lesion characterised by the rapid proliferation of a type of cell called fibroblasts (which are involved in the formation of connective tissue) in the tissue under the skin and surrounding muscles.¹ Nodular fasciitis is not cancerous, despite its resembling some malignant growths, and it usually goes away on its own or can be surgically removed. Nodular fasciitis primarily affects young and middle-aged adults and affects all genders equally.¹ Nodular fasciitis is comparatively uncommon, making up a negligible portion of soft tissue tumours. Studies indicate an incidence rate of roughly 1.3 incidents per 100,000 people annually.¹ Clinically, nodular fasciitis usually presents as a painless nodule that expands quickly. Due to its propensity to mimic aggressive soft tissue growths like sarcomas, a precise diagnosis requires careful histological analysis and immunohistochemistry.¹

When examined histologically (through a microscope), Nodular Fasciitis displays a characteristic pattern of rounded spindle cells organised randomly that are frequently accompanied by myxoid stroma changes and inflammation.² Nodular fasciitis can be distinguished from cancerous growths using immunohistochemical markers, meaning the presence of certain molecules that can be detected through tissue staining and microscope analysis. Common markers for Nodular fasciitis include smooth muscle actin and desmin.² The majority of the time, Nodular Fasciitis is a self-limiting disorder with the tendency to spontaneously regress within a few weeks to months despite its problematic presentation. The main course of treatment for patient worries and establishing a confident diagnosis is surgical excision.² Given this condition’s benign nature and potential for spontaneous resolution, it is crucial to accurately identify it to prevent needless invasive treatments.

Causes and risk factors of nodular fasciitis

The exact cause of Nodular fasciitis' is still unknown; however, reactive or inflammatory processes are thought to be responsible rather than any genetic factors. Physical trauma, minor injuries, and tissue irritation are examples of potential risk factors since they may result in aberrant responses in the healing process of the tissue.³ There have also been suggestions that hormonal effects, such as pregnancy and hormone treatments, could also lead to the development of nodular fasciitis.³ Although nodular fasciitis can strike anyone at any age, it primarily affects people in their 20s to 40s.³ Although the illness is mostly non-cancerous and doesn't often return after excision, a precise biopsy diagnosis is essential to rule out any possibility of malignancy. To avoid additional treatments and guarantee the best results, early detection and effective care are essential. 

Signs and symptoms of nodular fasciitis

A variety of signs and symptoms associated with nodular fasciitis commonly appear, varying in severity. The common traits are as follows:

• Rapid Growth: The most obvious characteristic is the nodule or lump in the affected area that quickly grows in size. This expansion happens gradually over a few weeks or months.⁴
• Pain or Discomfort: Because of the nodule's quick growth and impact on surrounding tissues, there may be pain, tenderness, or discomfort.⁴
• Skin Redness and Swelling: Localised inflammation can cause redness and swelling of the skin, which frequently looks like an infection or another inflammatory condition.⁴
• Mobility: Unlike more adherent or immovable masses, the nodule is typically mobile under the skin.⁴
• Size: Nodular fasciitis can range in size from a few millimetres to several centimetres. Due to its rapid growth, it may vary in shape over time.⁴
• Location: Lesions are usually in the extremities, particularly the upper limbs; the tumour typically develops in the subcutaneous tissue, deep fascia, or muscle layers.⁴
• Skin Changes: As a result of the growth's impact on nearby structures, the skin that overlays the affected area may experience changes like discolouration, thinning, or dimpling.⁴
• Firmness and Consistency: The nodule is typically firm to the touch, though it may have a softer centre because of enhanced blood flow.⁴

Diagnostic methods of nodular fasciitis

Diagnostic procedures such as imaging, histological examination, and clinical evaluation are frequently combined to diagnose nodular fasciitis. The main diagnostic techniques are listed below:

Clinical evaluation

 It is essential to conduct a comprehensive medical history and physical examination. Nodular fasciitis may be suspected if a deep-seated or subcutaneous nodule grows quickly and exhibits accompanying symptoms like pain and soreness.

Imaging studies

 Although they are not always required, imaging tests such as an ultrasound, MRI, or CT scan can help determine the size and location of the nodule.⁵ These tests can help rule out further problems and direct additional diagnostic procedures.

Biopsy

A biopsy is typically used to provide a conclusive diagnosis of nodular fasciitis. A small tissue sample is often removed from the nodule using an incisional biopsy or fine-needle aspiration (FNA).⁵ After that, a pathologist will examine the sample under a microscope.

Histopathological examination

A pathologist examines the tissue sample under a microscope. A characteristic feature of nodular fasciitis is the presence of spindle-shaped fibroblasts that divide quickly and the presence of inflammatory cells. These cells frequently have a "myxoid" appearance, which describes them as seeming gelatinous or mucous-like.⁵

The distinction between nodular fasciitis and other illnesses, such as sarcomas or other benign tumours, can occasionally be difficult. Therefore, a proper diagnosis is crucial to directing the right care, which may include either surgical removal or monitoring. To ensure the correct diagnosis and best course of treatment a medical specialist, typically an oncologist or pathologist, should be seen.⁵

Differential diagnosis of nodular fasciitis

The symptoms of Nodular fasciitis often resemble those of other illnesses. Differential diagnosis entails evaluating these alternative diagnoses and distinguishing nodular fasciitis from them. The following are some of the primary conditions that are considered for making a nodular fasciitis differential diagnosis:

• Fibromatosis (Desmoid Tumour): Like nodular fasciitis, fibromatosis is a benign but locally aggressive tumour that develops from fibrous tissue.⁶ Based only on clinical and imaging characteristics, it might be challenging to distinguish from nodular fasciitis.
• Superficial fibromatosis: Also known as palmar or plantar fibromatosis, superficial fibromatosis causes nodules or lumps to appear on the palms of the hands or soles of the feet.⁶ Though less aggressive and more slowly growing than nodular fasciitis, they share several common features
• Neurofibroma: Peripheral nerve tumours called neurofibromas can appear as nodules under the skin. They may seem somewhat like nodular fasciitis; however, they are related to neurofibromatosis type 1 (NF1) and have different histological characteristics.⁶
• Synovial Sarcoma: This cancerous tumour, particularly in its early stages, might resemble nodular fasciitis in appearance. Histopathological analysis is essential to rule out the malignant tumour.⁶
• Fibrosarcoma: Although nodular fasciitis is benign, it might mimic a malignant fibrosarcoma.⁶ To draw a clear differentiation, histopathological examination is required.
• Inflammatory Myofibroblastic Tumour: This uncommon tumour can develop in a variety of organs and tissues and may resemble nodular fasciitis in its symptoms.⁶ For proper management, it is crucial to distinguish between the two.
• Giant Cell Tendon Sheath Tumour: This benign tumour frequently affects the hand and digits and might clinically resemble nodular fasciitis.⁶ For a precise diagnosis, histopathology is essential.
• Lipoma: If found deeper within tissues, lipomas, which are benign fatty tumours, may occasionally be mistaken for nodular fasciitis.⁶

Treatment and management of nodular fasciitis

The size, location, and symptoms of the tumour, as well as the patient's general health, all play a role in the management and treatment of nodular fasciitis. The principal methods are as follows:

Observation

A "wait and watch" strategy may be suitable in some circumstances, particularly when the nodule is small and asymptomatic. Imaging and regular monitoring can be used to monitor the growth and ensure it is benign.

Surgery

The most frequent form of treatment for nodular fasciitis is surgical excision. When the nodule is causing pain, discomfort, or functional impairment, surgical removal of the tumour is the choice of treatment.

Corticosteroid injections

If surgery is not immediately possible or if the tumour is causing severe discomfort, corticosteroid injections into the nodule may be explored in some circumstances. By doing so, you can lessen inflammation and limit growth.⁷

Conservative measures

Painkillers and anti-inflammatory medication may be provided to treat tumour-related symptoms such as pain, discomfort, and swelling.

Physical therapy

Following surgery, physical therapy and rehabilitation may be advised to regain mobility and function in the injured area.

Regular follow-up appointments are necessary to track the healing process and catch any potential recurrences, regardless of the chosen treatment.⁷

Prognosis

Nodular fasciitis typically has a good prognosis. It is a benign disorder with little chance of metastasizing or spreading. Recurrence is rare after surgical removal of the tumour. Early discovery, proper diagnosis, and suitable care result in little to no long-term damage. A regular check-up ensures continuous health and keeps an eye out for any possible recurrence.⁸

Summary

Nodular fasciitis is an uncommon benign soft tissue tumour with nodular formation and rapid growth. Although the actual origin is still unknown, the illness often has a good prognosis and is not malignant. To rule out malignancy and provide proper therapy, which frequently entails surgical excision, early detection through biopsy is essential. Nodular fasciitis has a minimal recurrence rate following correct removal.. Patients, healthcare professionals, and pathologists are required to work together to provide an accurate diagnosis, prompt intervention, and advise the best course of treatment.