- arise from stromal or supporting tissues (CT, muscle, blood vessels)

- benign forms end in "-oma"

- malignant forms end in "-sarcoma"

- typically spread by blood (hematogenously)

Mesenchymal Neoplasms

 - benign/malignant neoplasm of fibrocytes

Fibroma/Fibrosarcoma

- benign/malignant neoplasm of adipocytes

Lipoma/Liposarcoma

- benign/malignant neoplasm of smooth muscle

Leiomyoma/Leiomyosarcoma

- benign/malignant neoplasm of Skeletal Muscle

Rhabdomyoma/Rhabdomyosarcoma

- benign/malignant neoplasm of blood vessels

Hemangioma/Angiosarcoma

- malignant neoplasms of astrocytes both low/high grade

Astrocytoma/Glioblastoma

- benign/malignant neoplasm of nerve cells

Neuroma/Neuroblastoma,Medulloblastoma

- malignant neoplasm of the retina

Retinoblastoma

- benign/malignant neoplasm of melanocytes in skin

Nevus/Melanoma

- arise from pleuripotent stem cells which can differentiate into cell lines of more than one dermal origin (multiple types of mature tissues)

Germ cell neoplasms

- malignant neoplasm of germ cells without differentiation

Seminoma (males) or Dysgerminoma (females)

- Benign/Malignant neoplasms of the placenta

Hydatidiform Mole/Choriocarcinoma

- benign/malignant neoplasm of mixture of mature tissues

Mature Teratoma/Immature Teratoma

- malignant neoplasms of the myeloid or lymphoid hematopoietic stem cells

- diffusely replace the bone marrow, spill into blood

- may be acute (immature/progressive) or chronic (mature/prolonged)

Leukemias

- malignancies of lymphocytes which form solid tissue masses

- do not spill over into the peripheral blood

- frequently involve marrow

- Hodgkin's or Non-Hodgkin's

Lymphomas

- always malignant

- 20% of lymphomas

- primarily involves lymph nodes

- Reed-Sternburg cells (giant, multinucleated cells w/ red nucleoli)

- non-neoplastic host response

- depression of T-cell function

Hodgkin's Lymphoma

- do not have Reed-Sternburg cells

- 80% of lymphomas

- involve lymph nodes

- 1/3 of cases are other tissues

- various stages of normal lymphocyte transformation

- B or T cell (80/20)

Non-Hodgkin's lymphomas

- malignant proliferation of plasma cells (transformed B cells)

- remains in bone marrow

- causes lytic lesions in the bones

- cells secrete monoclonal immunoglobulin (M-protein)

- Bence-Jones protein may show up in urine (kappa/lambda light chain)

- Amyloidosis is most often associated with Bence-Jones

- most pt's die of infection due to lowered immunity

Multiple myeloma