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.




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.




Floret Cells in Pleomorphic Lipoma [Pathology Infographic]


Pleomorphic lipoma occur in adults and are more common in males.
These are located on the back of the neck, upper back or shoulders.
These tumours usually present as a solitary, painless, slow growing, lobular mass with an average diameter of 5 cms. Rarely multiple lesions may develop.
Cut surface has a yellow or grayish – yellow colour. Sometimes mucoid areas are present.
There are overlapping features with spindle cell lipoma.

This tumour should not be mistaken for a  liposarcoma.