Aggressive Angiomyxoma – A rare locally aggressive soft tissue tumour

 

Aggressive angiomyxoma is a locally aggressive mesenchymal tumour. 

This tumour usually occurs in women of reproductive age and is located in the perineal or pelvic region.

Histologically, this enigmatic soft tissue tumour is characterized by a prominent myxoid matrix and numerous thin-walled blood vessels.

Elkattah R, Sarkodie O, Otteno H, Fletcher A. Aggressive Angiomyxoma of the Vulva: A Précis for Primary Care Providers. Case Reports in Obstetrics and Gynecology. 2013;2013:183725. doi:10.1155/2013/183725.

 

Myxofibrosarcoma – A malignant neoplasm of fibroblastic origin [Pathology Infographic]

 

Myxofibrosarcoma, is the most common soft tissue sarcoma in the extremities of the elderly patients ( between sixty and eighty years of age).

Histopathologically, the tumour is characterized by spindle cellular proliferation with moderate cellular density in fibromyxoid stroma.

Source: De Castro BAC, Piancastelli ACC, Meyer RLB, Piancastelli PM, Ribeiro CA, Miranda RMC. Myxofibrosarcoma – Case report. Anais Brasileiros de Dermatologia. 2016;91(1):97-99. doi:10.1590/abd1806-4841.20163922.

 

Myxoinflammatory Fibroblastic Sarcoma: A distinct soft tissue tumour of low-grade malignancy [Pathology Infographic]

 

Myxoinflammatory fibroblastic sarcoma is a rare, painless, and intermediate (rarely metastasizing) fibroblastic tumor, which commonly occurs in the extremities, with an equal sex predilection.

This sarcoma is composed of a mixed inflammatory infiltrate along with spindled, epithelioid, and bizarre tumor cells in a background of hyaline and myxoid areas.

In spite of such a distinctive morphology, the tumor can be a diagnostic challenge, simulating inflammatory conditions as well as neoplastic nature.

For accurate diagnosis, the tumor requires extensive clinical, radiological, and pathological investigations.

 

Source:

Kato M, Tanaka T, Ohno T. Myxoinflammatory Fibroblastic Sarcoma: A Radiographical, Pathological, and Immunohistochemical Report of Rare Malignancy. Case Reports in Orthopedics. 2015;2015:620923. doi:10.1155/2015/620923.

 

Giant cell angiofibroma : A soft tissue tumour with Floret-like giant cells [Pathology Infographic]

A giant cell rich form of hemangiopericytomas-solitary fibrous tumors was described by Dei Tos as  Giant cell angiofibroma (GCA).

Although originally identified in the orbital region, this tumor may occur in diverse locations.

GCAs are well-circumscribed variably encapsulated, small (median, 3 cm) lesions.

The morphological hallmark is a richly vascularized spindle cell proliferation containing pseudovascular spaces and floret -like multinucleate giant cells.

Mitotic activity range from 1 to 3 mitoses/10 high-power fields.

Treatment of GCA consists of simple tumorectomy.

Source: Pala EE, Beyhan R, Bayol U, Cumurcu S, Kucuk U. Giant Cell Angiofibroma in Unusual Localization: A Case Report. Case Reports in Pathology. 2012;2012:408575. doi:10.1155/2012/408575.

Superficial acral fibromyxoma – Fibromyxoid tumor of the hands and feet [Pathology Infographic]

 

Superficial acral fibromyxoma (SAF) is a fibromyxoid tumor with a predilection for the hands and feet, which was first described in 2001.

Superficial acral fibromyxoma most often presents as a slow-growing, nodular mass at acral sites.

Previously published series suggest that the toes are more commonly affected than the fingers, with the majority involving the subungual or periungual region; however, the heel, palm, and ankle can also be affected.

Males are affected approximately twice as often as females, with the average age of presentation in the fifth to sixth decade of life.

 Most tumors are asymptomatic or only mildly tender with pressure, often leading to a delay in patients seeking medical treatment.

Management of these tumors typically involves complete excision to rule out malignancy and prevent recurrence.

The gross appearance of the tumor is typically a firm, nodular, or lobulated mass with a whitish cut surface that can range from solid to gelatinous.

The tumor usually involves the dermis, often with extension into the subcutaneous tissue.

Occasionally, extension to the fascia or periosteum can cause pressure erosion of the underlying bone.

The histologic appearance of SAF consists of fibroblast-like cells with a storiform or fascicular pattern embedded in a predominantly myxoid, myxocollagenous, or collagenous matrix.

Increased numbers of ectatic blood vessels and mast cells are commonly seen.

Tumor cells typically express CD34, CD99, vimentin, and epithelial membrane antigen and are negative for cytokeratin, muscle, and melanocytic markers.

Wei C, Fleegler EJ. Superficial Acral Fibromyxoma of the Thumb. Eplasty. 2013;13:ic13.

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Park S-W, Kim J-H, Shin H-T, et al. Superficial Acral Fibromyxoma on the Palm. Annals of Dermatology. 2014;26(1):123-124. doi:10.5021/ad.2014.26.1.123.

Calcifying Aponeurotic Fibroma – A rare, benign fibrous tumour [Pathology Infographic]

 

Calcifying aponeurotic fibroma (CAF) is a rare, locally aggressive fibroblastic lesion that occurs predominantly in the distal extremities of children and adolescents.

CAF occurs in patients over a wide age range; however, it is most common in children and adolescents . The median ages for male and female patients are 11 and 12 years, respectively.

CAF grows in a diffuse, poorly circumscribed manner and is often attached to the aponeurosis, tendons or fascia. Complete local excision is the treatment of choice.

The histological examination of the lesion reveals two components:

i) Fibromatosis-like spindle-shaped cell elements, and ii) nodules of calcification, accompanied by more rounded, epithelioid cells.

Two phases have been described in the development of CAF  ; in the initial phase the tumor has an infiltrative growth and often lacks calcification, whilst in the later phase the tumor is more compact and nodular and exhibits a more prominent degree of calcification and cartilage formation, as seen in the present case.

The pathogenesis of CAF remains uncertain; however, a fibroblastic/myofibroblastic origin has been suggested . It has been previously demonstrated using immunohistochemistry that the tumor cells usually express vimentin and smooth muscle actin, but are negative for desmin , and these results are in accordance with this proposal.

Source: NISHIO J, INAMITSU H, IWASAKI H, HAYASHI H, NAITO M. Calcifying aponeurotic fibroma of the finger in an elderly patient: CT and MRI findings with pathologic correlation. Experimental and Therapeutic Medicine. 2014;8(3):841-843. doi:10.3892/etm.2014.1838.

 

Angiomyofibroblastoma [Pathology Infographic]

 

Angiomyofibroblastoma is a rare tumor that occurs in the genital tract, vulva, perineum, and pelvis of women.

In men, angiomyofibroblastoma-like tumors are known to occur in areas such as the inguinal area, scrotum, and perineum.

In 1997, Nucci et al first described an angiomyofibroblastoma-like tumor as a cellular angiofibroma .

Thereafter, in 1998, Laskin et al termed it an angiomyofibroblastoma-like tumor .

Clinically, the tumor has asymptomatic, well-circumscribed, and slowly growing characteristics.

Lee SH, Yang JW, Do JM, et al. Angiomyofibroblastoma-Like Tumor of the Scrotum. Korean Journal of Urology. 2010;51(5):365-367. doi:10.4111/kju.2010.51.5.365.

 

 

Pleomorphic Hyalinizing Angiectatic Tumour [Pathology Infographic]

 

Pleomorphic hyalinizing angiectatic tumors (PHATs) are non-metastasizing soft-tissue tumors of uncertain lineage occurring within the superficial subcutaneous tissues and muscles .

Presents in adults between the ages of 10 and 83 years (median age of 51 years), PHATs are more commonly observed in females than in males.

The majority of affected patients present with slowly-growing, painless masses, most commonly involving the lower extremities.

Rarer tumor sites include the arm, chest wall, axilla, popliteal fossa, buttocks, inguinal region, perineum, buccal mucosa and breast.

 

SUZUKI K, YASUDA T, HORI T, et al. Pleomorphic hyalinizing angiectatic tumor arising in the thigh: A case report. Oncology Letters. 2014;7(4):1249-1252. doi:10.3892/ol.2014.1883.

 

 

Alveolar Soft Part Sarcoma [Pathology Infographic]

 

Alveolar soft part sarcoma is a slow growing but, highly malignant tumour.

This rare, distinctive sarcoma, typically occurring in young patients was first described by Christopherson et al in 1952.

 

Cellular Neurothekeoma [Pathology Infographic]

Neurothekeoma  is an uncommon, benign, dermal tumour which should not be confused with a  Nerve sheath myxoma.

Important features of Cellular Neurothekeoma explained in an infographic .