Ossified soft tissue leiomyoma in a patient with sickle cell anemia

Osseous metaplasia in leiomyomas is extremely rare. Here, we report the case of an ossified subcutaneous leiomyoma in a 34-year-old African American man with sickle cell thalassemia who presented with a painful nodule of the scapular region, which appeared as a heavily mineralized soft tissue mass on chest radiographs. Histopathologic and immunohistochemical examination of the resected nodule revealed a benign soft tissue leiomyoma composed of intersecting fascicles of spindle cells that strongly expressed smooth muscle actin and caldesmon. Extensive intratumoral calcification and ossification were noticed. Only eight cases of ossified leiomyoma have been reported, of which two arose in the deep soft tissue.     

Two cases of male nipple leiomyoma: idiopathic leiomyoma and gynecomastia-associated leiomyoma

We describe 2 cases of male nipple leiomyoma. A 70-year-old man had a painful subcutaneous tumor on his left nipple of 6 months duration. Histopathology disclosed dermal spindle cells with oval-shaped nuclei forming interlacing bundles with irregular pattern. Glandular elements were absent. The spindle cells were positive to α-smooth muscle actin, desmin, and vimentin. Estrogen receptor (ER) and progesterone receptor (PrR) were negative. We diagnosed this case as male leiomyoma of the nipple. Another patient was a 61-year-old man with gynecomastia induced by spironolactone of 6 months duration. He also had a painful nodule on his left nipple and histopathology disclosed spindle-shaped tumor cells as in the previous patient. The tumor was accompanied by glandular elements in the deep dermis and subcutaneous tissue, which showed apocrine secretion and were positive for α-smooth muscle actin, ER, and PrR. These glandular elements were interpreted as mammary gland. But ER and PrR stain did not show positive results for leiomyoma in the upper dermis. To the best of our knowledge, this is the first report of male idiopathic and gynecomastia-induced leiomyoma with ER and PrR staining.     

Differential expression of smooth muscle myosin, smooth muscle actin, h-caldesmon, and calponin in the diagnosis of myofibroblastic and smooth muscle lesions of skin and soft tissue

The diagnosis of low-grade and pseudosarcomatous spindle cell lesions of skin and soft tissue can sometimes be problematic; in particular, distinction between fibroblastic, myofibroblastic, and smooth muscle proliferations can occasionally pose difficulties on routine histologic examination. We have applied a panel of immunohistochemical markers to a series of spindle cell lesions of skin and soft tissue to assess the utility of the differential expression of smooth muscle and myofibroblastic-associated markers. Twenty-eight cases of nodular fasciitis, 42 cases of fibromatosis, and 3 cases of myofibroblastic sarcoma were stained with antibodies against smooth muscle actin (SMA), smooth muscle myosin (SMMS), calponin, and high-molecular weight caldesmon (h-caldesmon). For comparison, 12 cases of cutaneous leiomyoma and 8 cases of leiomyosarcomas involving superficial soft tissues and fascia were studied with the same panel of antibodies. Thirty-eight of 42 cases of fibromatosis were positive for SMA, 42/42 cases were positive for calponin, 39/42 cases were negative for SMMS, and all cases were negative for h-caldesmon. All cases of nodular fasciitis were positive for SMA and calponin, and all were negative for h-caldesmon and SMMS. All cases of myofibroblastic sarcoma were positive for SMA and 2/3 cases for calponin, and were negative for SMMS and h-caldesmon. All cases of cutaneous leiomyoma and leiomyosarcoma were positive for all 4 markers tested. Our results demonstrate a remarkably consistent pattern of reactivity of muscle and myofibroblastic-associated markers in lesions predominantly composed of myofibroblastic spindle cells, characterized by positive staining for SMA and calponin and absence of reactivity for SMMS and h-caldesmon. Application of this panel of stains may be of aid in the differential diagnosis of low-grade myofibroblastic lesions such as nodular fasciitis and fibromatosis from smooth muscle tumors of skin and soft tissue. This panel may additionally be of assistance in the diagnosis of myofibroblastic sarcoma.     

Primary giant cell tumor of soft tissue

BACKGROUND: Primary giant cell tumor of soft tissue, also known as soft tissue giant cell tumor of low malignant potential, is a rare soft tissue tumor located in both superficial and deep soft tissue. Histologically, these lesions bear a close resemblance to their bony counterparts, giant cell tumor of bone, with round to spindle-shaped cells intimately admixed with uniformly scattered osteoclast-like multinucleated giant cells. In 1989 in the dermatology literature, two malignant giant cell tumors of soft parts were described that filled the dermis and extended into the subcutaneous tissue. METHODS: The authors report the rare occurrence of a giant cell tumor of soft tissue occurring primarily in the dermis that lacks overtly malignant features and clinically was thought to be an epidermal inclusion cyst. RESULTS: Light microscopy revealed a non-encapsulated cellular dermal tumor containing numerous osteoclast-like giant cells. Cytologic atypia was minimal and the mitotic count averaged 2-3/10 HPF. The histologic differential diagnosis is also discussed. CONCLUSION: Giant cell tumor of soft tissue is a rare neoplasm of the skin, however, recognition of this tumor is important due to its behavior as a low-grade malignancy.     

Ossifying fibromyxoid tumor – A case report

Ossifying fibromyxoid tumor (OFMT) is a rare soft tissue tumor of uncertain histogenesis, occurring predominantly in deep soft tissues of the extremities. Typically, OFMT presents in adults on the extremities or trunk, as a deep soft tissue mass. Less appreciated is the fact that OFMT may also present as a mass in the superficial subcutis or dermis. We herein report a female who presented with an asymptomatic subcutaneous nodule on the left thigh for 3 years, and who was diagnosed as having typical ossifying fibromyxoid tumor, by unique histopathologic and immunohistochemical studies. Most reported cases have pursued a benign clinical course. However, recent literature emphasized the existence of morphologically atypical and clinically malignant cases of OFMTs. Pathologic criteria for malignancy have been proposed, and reclassification of these tumors as tumors of intermediate malignancy, raise our attention while coping with OFMT clinically.     

A Case of Dedifferentiated LiposarcomaThat Developed in the Dermis

Dedifferentiated liposarcoma is a variant of liposarcoma, and this is characterized by the coexistence of well-differentiated liposarcoma with areas of poorly differentiated, non-lipogenic tumor and this is also known to be associated with more aggressive behavior. Dedifferentiated liposarcoma occurs principally in the retroperitoneum or the deep soft tissue of limbs, but it can also occur in subcutaneous locations. We report here on a peculiar case of dedifferentiated liposarcoma that developed in the dermis, which is an exceedingly rare location for this type of tumor. The occurrence of this tumor in the dermis made it easy to surgically remove and monitor for recurrence, and we expect this patient to have a better prognosis than that of a patient with dedifferentiated liposarcoma located in the retroperitoneum or deep soft tissue.     

Histopathologic diagnosis of superficial soft tissue tumors, related lesions, and simulators: an algorithmic approach based on colors: tumors with predominance of pink

An algorithmic approach based on colors for histopathologic diagnosis of soft tissue tumors and their simulators is proposed. At scanning magnification, in specimens stained with hematoxylin and eosin, mesenchymal tumors can be classified according to their color. The color of a tumor is basically determined by density, morphology, and distribution of neoplastic cells, and by density and quantity of the stroma. The basic colors that can be observed by neoplasms stained with hematoxylin and eosin are white, pink, red, and blue. Colors may be used as a first step in choosing the algorithm for specific diagnosis of a given mesenchymal neoplasm. Furthermore, colors may be helpful in understanding the histogenesis of a tumor, and this is especially important in soft tissue pathology, because criteria for benignancy and malignancy vary according to the nature of the neoplasm. In this article, tumors with a predominance of pink are analyzed. Pink tumors are composed of cells with abundant eosinophilic cytoplasm and sparse chromatin in their nuclei, such as leiomyoma. In other cases, the pink color in a tumor is determined by abundant fibrous stroma rather than by characteristics of neoplastic cells, such as sclerotic fibroma.     

Granular cell tumor of the suprasternal space

A case of granular cell tumor (GCT) was reported. We encountered a 33‐year‐old woman with a painless, elastic, hard mass in the soft tissue of the suprasternal space. The tumor was excised with several millimeters margin of normal tissue above the deep cervical fascia and the wound was closed primarily. Histological examination on hematoxylin–eosin stain showed a tumor growth in the mid‐ to deep dermis and eosinophilic small granules that were consistent with granular cell tumors. Immunohistochemical studies showed positive staining for S‐100 protein. We experienced a case of a granular cell tumor occurring in the suprasternal space and report the importance of including it in the differential diagnosis of subcutaneous soft tissue tumors.     

Subcutaneous tissue: anatomy and aging

A deep understanding of the soft tissue from the face and his aging is necessary when dealing with facial volume injections.     

Myoepithelial carcinoma on the right shoulder: Case report with published work review

Myoepithelial carcinoma is a malignant tumor that can differentiate towards myoepithelial cells and commonly occur in the salivary glands. There have been only a few reports of primary cutaneous myoepithelial carcinoma; however, most cases showed subcutaneous involvement and could also be diagnosed as soft tissue myoepithelial carcinoma arising from the subcutis with dermal involvement. It may thus be impossible to distinguish a primary cutaneous from a soft tissue myoepithelial carcinoma. Herein, we describe a case of myoepithelial carcinoma on the shoulder in an 85‐year‐old Japanese woman. The tumor was located in the whole dermis and subcutis; therefore, it could be diagnosed as either a cutaneous or soft tissue myoepithelial carcinoma. We reviewed previous cases of primary cutaneous and soft tissue myoepithelial carcinomas and compared their clinical and immunohistological features. We found no obvious differences in anatomical distribution or immunohistochemical findings. However, the recurrence rate of cutaneous myoepithelial carcinomas seems to be lower than that of soft tissue carcinomas. Such a difference may be attributable to the adequate surgical margin in cutaneous carcinomas compared with the deep‐seated soft tissue carcinomas. The metastatic frequency did not significantly differ between the two types. Although we could summarize from only a small number of cases, these results indicate the difficulty in distinguishing between cutaneous and soft tissue myoepithelial carcinomas; furthermore, it may not be suitable to distinguish them on the basis of aggressive behavior.     

Rare,risky, recurrent: An enigmatic cutaneous polyp

Myxofibrosarcomas (MFSs) are sarcomas most commonly seen in older patients. These are tumors of deep soft tissue seen in subcutaneous tissue and deep fascia, with frequent muscle involvement. These sarcomas are notorious for recurrences and progression to a higher grade with notable metastatic potential. They are very often under‐diagnosed owing to their inherent morphological variability. A case of MFS is presented as a cutaneous, exophytic, polypoidal mass because of its rarity and importance of timely diagnosis, as under‐diagnosis may lead to inadequate clearance of tumor, recurrences, metastases and increased mortality.     

Low-grade fibromyxoid sarcoma: case report and immunohistochemical study

A case is presented of low-grade fibromyxoid sarcoma involving the arm of a 52-year-olcl man. Low-grade fibromyxoid sarcoma is a recently described neoplasm of the deep and subcutaneous soft tissue which demonstrates a spectrum of histologic images. The current case demonstrated the typical patterns of intermixed, sweeping bands of fibrous and myxoid tissue, homogeneous foci of fibrous and myxoid tissue, focal areas of storiforming, and concentric perivascular cuffs of slender spindle cells, all lacking the nuclear anaplasia, mitotic activity, and necrosis generally associated with sarcomas. Immunohistochemical analysis performed on paraffin-embedded sections demonstrated strong labeling of the tumor cells by anti-CD34 antibody, moderate labeling for vimientin, and rare, focal positivity for muscle-specific actin. Tumor cells were negative for markers of epithelial, muscular, neural, histiocytic, melanocytic, and vascular differentiation. The constellation of histopathologic features described in this arid previous reports is characteristic of low-grade fibromyxoid sarcoma. Based on this case, it appears that the immunohistochemical features of low-grade fibromyxoid sarcoma can help to exclude many cutaneous and deep soft tissue tumors from the differential diagnosis. The findings support the interpretation that the neoplasm is essentially fibroblastic in nature.     

Bilateral tibialis anterior muscle herniation simulating a soft tissue tumour in a young amateur football player

Muscle herniation is a focal protrusion of muscle tissue through a defect in the deep fascial layer. Anterior tibial muscle is the most commonly affected muscle of the lower extremities because its fascia is the most vulnerable to trauma. Clinically it is characterized by asymptomatic or painful, skin‐coloured, soft, subcutaneous nodules of various size depending on the position. The diagnosis is usually made clinically based on its typical manifestations, but ultrasonographic examination is useful for detecting the fascial defect and excluding other conditions caused by soft tissue tumours such as lipomas, angiolipomas, fibromas, scwhannomas or varicosities. Although this entity is not rare, it has been less well documented in the dermatological literature. We report a case of bilateral tibialis anterior muscle herniation mimicking a soft tissue tumour in a young amateur football player.     

Neonatal Rhabdomyosarcoma Misdiagnosed as a Congenital Hemangioma

Abstract: Highly vascularized malignant soft‐tissue tumors can clinically and radiologically mimic deep hemangiomas. We present a case of congenital rhabdomyosarcoma of the neck, which was initially identified as congenital hemangioma.     

Childhood Cutaneous Leiomyosarcoma

Abstract:   Cutaneous leiomyosarcoma is a soft tissue neoplasm exhibiting an aggressive local behavior and a potential for distant metastases. It is rare during childhood and diagnosis can be challenging both clinically and histologically. Surgical excision with wide lateral and deep margins is the treatment of choice, whereas radiotherapy and chemotherapy are contraindicated. Long-term follow-up is necessary as recurrences are not infrequent.     

Benign fibrous histiocytoma of the eyelid with an unusual clinical presentation

Benign fibrous histiocytoma is a common soft tissue tumor that can be deep or superficially located. Although the deep type of fibrous histiocytoma has a predilection for the orbit, the eyelids are an unusual location for the cutaneous type. A 42-year-old woman had bilateral yellowish nodular masses of the eyelids for two years. Pathological examination after excision revealed benign fibrous histiocytoma. Our case is an unusual clinical presentation of cutaneous fibrous histiocytoma as well as a rare location such as the eyelids.     

Squamous cell carcinoma arising from an ischial pressure ulcer initially suspected to be necrotizing soft tissue infection: A case report

BackgroundPressure ulcers are the most common complications in bedridden patients or those with spinal cord injuries. Marjolin's ulcer refers to a malignant transformation arising from burn scars or chronic nonhealing wounds—such as pressure ulcers—over many years. Squamous cell carcinoma is the major histopathologic type of Marjolin's ulcer, and the gold standard for diagnosis is tissue biopsy. Medical professionals may have difficulty distinguishing pressure ulcers from Marjolin's ulcer, especially when the latter presents with invasive infections. Thus, malignant transformations arising from pressure ulcers are frequently overlooked. Herein, we describe a case of squamous cell carcinoma arising from pressure ulcers on the left ischium, which was initially identified as a necrotizing soft tissue infection.Case reportA 59-year-old paraplegic patient presented with stage 3 left ischial pressure ulcer, which involves full-thickness skin loss and extends into deep subcutaneous tissue, and arrived at our hospital with suspected sepsis. Upon physical examination, the patient presented with fever and shivering. Initial examination and imaging findings revealed the presence of necrotizing soft tissue infections. Three weeks later, rapid increase in granulation in the deep part of the ulcer was observed. Samples from multiples ulcer sites were collected for tissue biopsy. Finally, histological examination revealed well-differentiated squamous cell carcinoma. The patient received radiation therapy and chemotherapy and died 11 months after the diagnosis.ConclusionMalignant transformations arising from pressure ulcers may closely resemble pressure ulcer infections. In these cases, tissue biopsies should be performed during primary care for the infection to exclude malignant transformations.     

Malignant giant cell tumor of soft parts presenting as a skin tumor

Malignant giant cell tumor of soft parts is a rare neoplasm that histologically resembles a giant cell tumor of bone. It has a distinctive multinodular growth pattern and is composed of numerous osteoclast-like giant cells, histiocytes, and fibroblasts. Although this tumor is usually found in deep soft tissues, a superficial form has been described in the subcutaneous tissue and fascia. The authors report two patients, aged 75 and 78, with malignant giant cell tumors presenting as ulcerating skin nodules of the arm and foot. The tumors were relatively small, measuring less than 3.5 cm in greatest dimension, and involved the entire dermis and subcutaneous tissue. The clinical differential diagnoses included Kaposi's sarcoma, melanoma, and hematoma. Dermatopathologists and dermatologists should be aware of this entity to avoid confusion with other benign and malignant neoplasms that may contain multinucleated giant cells. The distinguishing histologic and immunohistochemical features of this tumor are discussed.     

Congenital extrarenal malignant rhabdoid tumor in an infant with distal 22q11.2 deletion syndrome: the importance of SMARCB1

Extrarenal rhabdoid tumor is a rare malignancy of infants and children, typically presenting in the soft tissue of deep, axial locations. We describe a rare dermal presentation of congenital extrarenal rhabdoid tumor in the left paraspinal region of a 6-month-old girl with germline deletion of chromosome 22q11.21q11.23. This case demonstrates that like other rhabdoid tumors, the SMARCB1 gene is also responsible for cutaneous extrarenal rhabdoid tumor oncogenesis.