Metachronous Occurrence of Granular Cell Tumor in Breast Skin and Scalp: Diagnostic Challenging Differentiating Benign from Malignant and a Literature Review

Abstract

Granular cell tumor (GCT) is a Schwann cell related benign neoplasm of soft tissue. GCT is an uncommon entity that occurs in a wide variety of body sites, but it is generally presented in the skin, oral cavity, superficial soft tissue, and respiratory and digestive tracts. Most of the GCTs are benign but clinically and radiologically these may mimic malignancy. Histopathological diagnosis is gold standard for establishing the true nature of the lesion. GCT is most commonly solitary but in about 10% of cases can be multifocal, usually involving various skin and soft tissue sites versus involving various internal sites. Therefore, these can involve skin and soft tissue or submucosa and viscera. GCT is usually benign; however, local recurrence is common due to incomplete removal. Malignant cases are rarely reported in 1-2% of cases. In this study, we report clinical and histopathological findings of a 36-year-old woman with metachronous GCT in breast and scalp. The clinical features raise the question of whether these are metachronous benign GCTs or whether this is establishment of malignant behavior. The aim of this report is to present the histopathological and clinical features of GCT and the diagnostic challenge of differentiating benign from malignant GCT.

Granular Cell Tumour of Larynx— A Case Report

“…Malignant transformation of these tumours is extremely rare with occurrence in less than 2% of the cases [5]. We present this case report due to its rarity of occurrence.…”

Granular cell tumors of the breast: an unusual case of multifocality—a case report

“…They can arise in any body site but predominantly are found in the digestive tract, oral cavity, and skin. They typically present as soft tissue neoplasms and were first reported by Abrikossoff and referred to as "granular cell myoblastoma" in the tongue and pharynx (1). They typically stain positive for S100 which is a marker for Schwann cells and GCTs are thought to arise from peripheral nerves.…”

Two Cases of Granular Cell Tumors that Clinically Mimicked Hypertrophic Scars and Keloids

“…Granular cell tumors (GCTs) are rare soft tissue tumors that were first reported by Abrikossoff 1 in 1926. While the differentiation of neoplastic cells has been disputed, it is now believed that GCTs differentiate towards Schwann cells 2 . GCTs frequently occur on the oral cavity, the skin, and subcutaneous tissue.…”

“…GCTs frequently occur on the oral cavity, the skin, and subcutaneous tissue. Although GCTs are basically benign, cases with distant metastases have been reported 2 . Thus, it is desirable to be able to diagnose GCTs preoperatively.…”

“…Thus, it is desirable to be able to diagnose GCTs preoperatively. However, it is extremely difficult to diagnose GCTs because although they have very characteristic histopathological features, their clinical findings are generally non-specific and the incidence of GCTs is very small 2 . We report here two cases of GCTs that occurred in rare sites and clinically mimicked hypertrophic scars and keloids, respectively.…”