Soft Tissue Tumors Pathology Study Guide

Soft Tissue Pathology Video

Lipoma

A lipoma is a benign tumor composed of adipose tissue that typically develops just beneath the skin.

Lipomas are most commonly seen in adults.

Lipomas may be treated by surgical excision.

Definitive diagnosis of lipoma is made by pathology showing a well circumscribed mass composed of benign adipocytes.

Histologic presentation of atypical lipoma. Atypical lipoma composed of mature fat and fibrous tissue with scattered, enlarged, hyperchromatic cells.The use of radiation therapy in the management of selected patients with atypical lipomas. Kang J, Botros M, Goldberg S, Giraud C, Nielsen GP, Chen YL, Raskin K, Schwab J, Yoon SS, Hornicek FJ, Delaney TF - Sarcoma (2013). Not Altered. CC.
Lipoma. X-ray of a lipoma Sebastian E Valbuena, Greg A O'Toole and Eric Roulot - Sebastian E Valbuena, Greg A O'Toole and Eric Roulot. Not altered. CC BY-SA 2.0
Lipoma. Small lipomas removed from arms John Cummings - Not altered. CC BY-SA 4.0
Lipoma. Fibrolipoma: Large amounts of fibrous tissue. Mikael Häggström, M.D. Not altered. CC0
Lipoma. Lipoma Sikander Iqbal. Not altered. CC BY 3.0
A: pathology slide showing normal cardiac tissue on left lower side and lipoma on right upper stained with hematoxylin and eosin (H and E) at 100 magnification. B: high-1000 magnification of boundary of normal cardiac and lipoma tissue.A rare case of a intracardiac lipoma. Singh S, Singh M, Kovacs D, Benatar D, Khosla S, Singh H - International journal of surgery case reports (2015). Not Altered. CC.
Lipomas. Panel (a) shows the macroscopic appearance of the duodenal lipoma with naked fat sign; panel (b) demonstrates pathological changes in the resected sample confirming the diagnosis of submucosa lipomas (H&E, × 400). Multiple Duodenal Lipomas as a Rare Cause of Upper Gastrointestinal Obstruction: Case Report and Literature Review. Maowei Pei, Mingrong Hu, Wenbin Chen, Chao Q.- Gastroenterology Research (2017). Not Altered. CC.

Liposarcoma

Liposarcomas are malignant tumors of adipose tissue.

Liposarcomas are very rare compared to lipomas (their benign counterparts).

Liposarcomas may metastasize.

Adults are more commonly susceptible to developing liposarcomas compared to children.

Definitive diagnosis of liposarcoma is made by pathology showing malignant proliferation of adipose tissue.

Lipoblasts are the characteristic cells seen in liposarcoma.

Treatment of liposarcomas involves surgical excision.

Liposarcoma. Lower-power micrograph of myxoid liposarcoma tumor No machine-readable author provided. KGH assumed (based on copyright claims). Not altered. CC BY-SA 3.0
Liposarcoma. A) Photomicrograph (H&E) showing characteristic liposarcoma histology with juxtaposed well-differentiated (WD, low grade) and dedifferentiated (DD, high grade) areas of the same tumor. (B) Sectioned WD tumor with a probable focus of DD (white circle).Hypothesis: The Intratumoral Immune Response against a Cancer Progenitor Cell Impacts the Development of Well-Differentiated versus Dedifferentiated Disease in Liposarcoma. Tseng WW, Chopra S, Engleman EG, Pollock RE - Frontiers in oncology (2016). Not ALtered. CC.
Liposarcoma. Histopathology of liposarcoma, H&E stain, with the main features: - Spindle cells with enlarged, hyperchromatic nuclei. - Apparently univacuolated adipocytes (may look normal). - Lipoblasts (multivacuolated), but neither necessary nor sufficient for diagnosis. This case was likely a myxoid liposarcoma as per immunohistochemistry. Reference: Michael R. Clay, M.D.. Liposarcoma. PathologyOutlines. Topic Completed: 1 November 2017. Minor changes: 11 May 2021 Mikael Häggström, M.D. Not altered. CC0
Liposarcoma. Micrograph of a dedifferentiated liposarcoma tumor Nephron - Not altered. CC BY-SA 3.0
Liposarcoma. Micrograph of bone formation in a liposarcoma tumor Mikael Häggström, M.D.. Not altered. CC0
Liposarcoma. Ultrasonography of a liposarcoma with high-echo areas reflected from its lipomatous matrix and low-echo areas reflected from its non-lipomatous areas.[69] Chee-Wai Mak and Wen-Sheng Tzeng - Not altered. CC-BY-3.0
Liposarcoma. ALT/WDL, adipocytic/lipoma-like. At low magnification, the tumor mostly contains adipocytes that appear benign and mature, but high magnification of one fibrous band shows abnormal spindle-shaped cells with enlarged, heterochromatic nuclei. Mikael Häggström, M.D. . Not altered. CC0
Myxoid Liposarcoma. Histology of myxoid liposarcoma. Low magnification image of myxoid liposarcoma showing a variable number of adipocytes and a prominent capillary pattern ((A), hematoxylin and eosin stain, original magnification ×50); myxoid liposarcoma with relatively low cellularity showing uniform oval tumor cells and prominent, branching capillary pattern with variable numbers of non-atypical adipocytes ((B), hematoxylin and eosin stain, original magnification ×100); branching capillary pattern staining with CD34 ((C), original magnification ×100); and presence of some multi-vacuolated lipoblasts ((D), hematoxylin and eosin stain, original magnification ×600). Trabectedin as second-line treatment in metastatic myxoid liposarcoma: a case report. Pedrinaci IZ, Jurado JM, Carrillo J, Molina MC - Journal of medical case reports (2012). Not Altered. CC.
Well Differentiated Liposarcoma. Histological diagnosis with hematoxylin-eosin showing malignant fibrous histiocytoma-like findings mixed with those for well-differentiated liposarcoma, leading to the diagnosis of dedifferentiated liposarcoma. a Well-differentiated liposarcoma components and malignant fibrous histiocytoma-like findings with a distinct border. b Malignant fibrous histiocytoma-like findings. c Well-differentiated liposarcoma components. A Retroperitoneal Dedifferentiated Liposarcoma Producing Granulocyte Colony-Stimulating Factor Accompanied by Spontaneous Rupture: PET/CT Imaging of a G-CSF-Producing Tumor. Hara R - Case reports in oncology (2011). Not Altered. CC.

Rhabdomyoma

Rhabdomyomas are benign tumors composed of skeletal muscle.

Rhabdomyomas can develop in heart muscle, termed cardiac rhabdomyomas, which are associated with tuberous sclerosis.

Although rhabdomyomas are uncommon in general, they are the most frequent kind of cardiac tumor among infants and young children.

Rhabdomyoma. Photomicrograph of fetal-type rhabdomyoma: Note the plump, pink benign skeletal muscle cells. Jerad M Gardner, MD - Not altered. CC BY-SA 3
Rhabdomyoma. This is a surgically excised specimen (unfixed) from the tumor illustrated in figure 5-3 showing a whitish tan cut surface. The Armed Forces Institute of Pathology (AFIP) -Not altered. Public Domain
Rhabdomyoma. (a) Low power view of the rhabdomyoma (left) with adjacent hypercellular parathyroid (right). (b) Normal striated muscle intertwined with tumor cells. (c) High power view of rhabdomyoma; notice the eosinophilic granular cytoplasm with small eccentrically and centrally placed nuclei. Much of the cytoplasm is retracted from the cell membrane. (Hematoxylin-eosin, original magnification ×40 (a), original magnification ×100 (b), and original magnification ×400 (c).)A rare soft tissue tumor masquerading as a parathyroid adenoma in a patient with birt-hogg-dubé syndrome and multiple cervical endocrinopathies. Mikesell KV, Kulaylat AN, Donaldson KJ, Saunders BD, Crist HS - Case reports in pathology (2014). Not Altered. CC.

Rhabdomyosarcoma

Rhabdomyosarcomas are malignant tumors composed mainly of skeletal muscle.

Rhabdomyomas typically effect skeletal muscle, or occasionally hollow organs like the bladder or uterus.

Diagnosis is made by histology showing malignant skeletal muscle with rhabdomyoblasts, which are the characteristic cells of rhabdomyosarcoma.

Pathology stains for rhabdomyosarcoma will be desmin stain positive.

Rhabdomyosarcomas often involve the head and neck in the majority of patients, but the vagina is the classic site in young girls.

Rhabdomyosarcoma. Photomicrograph showing nodules of tumor cells separated by hyalinised fibrous septae (50×, HE stain). Inset: Discohesive large tumor cells with hyperchromatic nucleus and scant cytoplasm (200×, HE stain). The diagnosis was postauricular congenital alveolar rhabdomyosarcoma. Mahesha Vankalakunti et al. - Mahesha Vankalakunti, Ashim Das and Narasimhan KL Rao. Not altered. CC BY 2.0
Rhabdomyosarcoma. Non-contrast computed tomography of head showing the hypoechoeic mass without any intracranial extension. The diagnosis was postauricular congenital alveolar rhabdomyosarcoma Mahesha Vankalakunti, Ashim Das and Narasimhan KL Rao. Not Altered. CC BY 2.0
a - Radical trachelectomy specimen of case # 1 with 5.3 × 2.9 × 6.7 cm cervical RMS involving the lower aspect of the cervix. b - The completely excised embryonal rhabdomyosarcoma is observed in the trachelectomy specimen with negative vaginal, uterine and parametrial margins. Fertility-sparing surgery for the management of young women with embryonal rhabdomyosarcoma of the cervix: A case series. Gynecologic Oncology Reports. Not Altered. CC.
Key imaging and pathology results from the Rhabdomyosarcoma and Diffuse large B-cell lymphoma. a Axial view of the left thigh rhabdomyosarcoma demonstrating the lesion was FDG-avid on PET scan. b Morphology of rhabdomyosarcoma showing spindle cells in intersecting fascicles. (H&E, 200x) c Immunohistochemical stain for Desmin showing diffuse positivity supporting the diagnosis of rhabdomyosarcoma. d Axial view of the mediastinal diffuse large B-cell lymphoma demonstrating FDG-avidity on PET scan. e Morphology of lymph node showing involvement by diffuse large B-cell lymphoma. (H&E, 200x) f Higher power image of the lymphoma showing large lymphoid cells in sheets. (H&E, 400x). A case report of concurrent embryonal rhabdomyosarcoma and diffuse large B-cell lymphoma in an adult without identifiable cancer predisposition Biomarker Research. Not Altered. CC
Alveolar Rhabdomyosarcoma. Monomorphic dense cell proliferation with a high nucleocytoplasmic ratio (alveolar rhabdomyosarcoma). Pituitary metastasis of rhabdomyosarcoma: a case report and review of the literature. Ismail E, Issam L, Hamid M - Journal of medical case reports (2014). Not Altered. CC.
Embryonal Rhabdomyosarcoma. Embryonal rhabdomyosarcoma consisting almost entirely of differentiated rhabdomyoblasts (H&E staining, ×40). Embryonal rhabdomyosarcoma of upper lid in 15-year-old patient. Sharifi M - Case reports in ophthalmological medicine (2014). Not Altered. CC.