Atypical cervical polyp with intracytoplasmic inclusions

Infantile digital fibroma/fibromatosis: a clinicopathologic and immunohistochemical study of 69 tumors from 57 patients with long-term follow-up

The clinicopathologic and immunohistochemical features of 69 pediatric examples of infantile digital fibroma/fibromatosis (IDF) were analyzed. Thirty males, 26 females, and 1 child (sex unstated) ranging from newborn to 120 months of age (median, 12 mo) manifested 74 lesions (5 identified in follow-up) involving the toe or finger (n=71) and the hand or foot (n=3). Tumors ranged in size from 3 to 35 (median, 10) mm. All but 4 study members presented with a solitary lesion. Metachronous IDFs developed in 7 patients within 17 to 82 months. Microscopically, a cytologically bland, fibroproliferative lesion was observed forming a dome-shaped/polypoid nodule directly beneath the epidermis and invading dermal adnexa. Mitotic figures per 20 high-powered fields ranged from 0 to 7 (median, 1). Paranuclear cytoplasmic inclusions were identified in 57 tumors. Tumor cells immunohistochemically expressed calponin (11 of 11 tumors), desmin (9/9), alpha-smooth muscle actin (11/11), CD99 (11/11), CD117 (6/8), heavy caldesmon (2/11 and scattered cytoplasmic inclusions in 4 tumors), CD10 (1/9), nuclear beta-catenin (2/11), and CD34 (1/11), but not muscle actin (HUC1-1), keratins, estrogen/progesterone receptor proteins, or activated caspase-3. Twenty-eight of 38 patients (74%) experienced recurrent/persistent disease (single in 22; multiple in 6) (median, 4 mo after surgery). One recurrent tumor spontaneously regressed and the size of another remained unchanged for almost 17 years before reexcision. All 23 patients with >5 years follow-up are currently disease free (median disease-free interval, 23 y). Minor postoperative functional/cosmetic complaints were reported in 47%. No patient with adequate clinical data developed the digitocutaneous dysplasia syndrome or a conventional fibromatosis, or relayed a family history of IDF/conventional fibromatosis. Our results indicate that IDF is a unique myofibroblastic process separable from conventional fibromatoses and from histologic mimics. Conservative excision or observation after biopsy (with additional surgery employed as necessary) are recommended treatment options.

Actin inclusions in stromal cells of fibroepithelial tumor of breast: immunohistochemical and ultrastructural studies

An uncommon occurrence of actin inclusions in the stromal cells of a benign fibroepithelial tumor of breast is reported. Histologically, many of the stromal cells contained round and eosinophilic intracytoplasmic inclusions identical to those seen in inclusion body fibromatosis. Ultrastructurally, these inclusions represented dense spherical clumps of microfilaments derived from rough endoplasmic reticulum. The literature was reviewed and follow-up data showed that the clinical course of these morphologically distinctive benign fibroepithelial tumors was relatively indolent if completely excised, in contrast to inclusion body fibromatosis, which commonly recurs. The pathogenesis may be related to abnormal production of truncated actin filaments or alteration in microenvironment.