Download MBBS (Bachelor of Medicine and Bachelor of Surgery) Pathology Miscellanous Tumours
Lipoma
Miscellaneous tumors
? MC soft tissue tumor
? Painless except ______
? Cytogenetics: Chr 6p, 12q and 13q
? Usually cured by simple excision
Liposarcoma: Morphology
? Lipocytes with supernumerary rings & giant rod chromosomes -
12q (MDM2 oncogene)
? Lipoblasts: scalloping of nucleus
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Liposarcoma
? Most common sarcomas of adulthood
? MC: proximal extremities & retroperitoneum
? t(12;16): Myxoid/round cell variant of liposarcoma
Fibromatoses:
Superficial
Deep
? Palmar- Dupuytren
? Desmoid tumors-
Tumors & Tumor-like lesions
contracture
? Locally aggressive
? Plantar
? Associated with Gardner
of fibrous origin
? Penile: Peyronie disese
syndrome (APC)
? Recurs
? Rx- wide Excision
Fibrosarcoma
? MC in extremities
? Herringbone pattern
? Aggressive
? Recurs
? Metastasises
n
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Inflammatory myofibroblastic tumor
? Benign spindle cell tumor along with scattered inflammatory cells
(lymphocyte and plasma cells)
? Occurs in viscera (lungs)and soft tissue of children and young adults
? ALK (2p23) gene mutation (hereditary hemorrhagic telangiectasia-1,
Adenocarcinoma lung, Neuroblastoma, Large, anaplastic large B cell lymphoma
Rhabdomyosarcoma (RMS)
? Primitive mesodermal origin
? MC soft-tissue sarcoma of childhood & adolescence
Tumors of skeletal muscles
? Most common---head/neck; 2 nd Mc----genitourinary
tract
Histology of RMS
Embryonal RMS (MC, 60%)
? Rhabdomyoblast
? It includes sarcoma botryoides
? Stains --
? Occurs in children < 10 yrs of age
desmin, MYOD1 & myogenin.
? Chr 11p involved
? Histologically sub-classified into:
? embryonal
? A submucosal zone of
? alveolar
hypercellularity -> cambium layer.
? pleomorphic
Tadpole or strap cells
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Sarcoma Botryoides
Treatment and prognosis of RMS
? At age < 5 yrs
? Rx: Surgery and chemotherapy with or without RT
? Grape like clusters in vagina
? Histologic type and location of tumor influence survival
? H/E: Tennis racket cells
? Rx: surgery + Chemotherapy
Best prognosis: Botryoid subtype
Intermediate prognosis: Embryonal NOS
Poor prognosis: pleomorphic and alveolar
Synovial Cell Sarcoma
? Only 10% intra-articular!!!
? MC around knee
Tumors of uncertain histogenesis
? H/E: Biphasic- epithelial & mesenchymal (spindle cells)
? Stains: Keratin, vimentin, S-100 & EMA
? Cytogenetics: t(X;18)
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Squamous Cell Carcinoma (SCC)
? 2nd most common tumor arising on sun-exposed sites
? Males>females (except on lower legs)
? Locally invasive; Metastasis uncommon
Tumors of Skin
? Risk factors: UV light, immunosuppression, HPV (5 & 8), tobacco
? p53 mutation
Squamous cell carcinoma
Keratoacanthoma
? A variant of well-differentiated squamous cell carcinoma
? After a period of rapid growth, it usually regresses spontaneously
Keratin pearls
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Basal Cell Carcinoma (Rodent ulcer)
Basal Cell Carcinoma
? Most common invasive skin cancer
? Slow-growing tumors, rarely metastasize.
? Seen in immunosuppression & xeroderma pigmentosum
? NBCCS or Gorlin Syndrome ? AD, multiple sites,
Chr 9: PTCH gene receptor for product of SHH (Sonic Hedgehog)
-
Pearly, telangiectatic
Tumor nests
Pallisading
gene, p53 mutation
nodule
Separation artefact
Melanoma
? 3 mutations:
? Predisposing factors are inherited genes and sun exposure (induced
? Cell cycle regulators(p16/INK4a, CDK4),
? Growth factor receptors e.g. BRAF, RAS,
mutations)
? TERT- activate telomerase
Growth patterns:
? Prognosis: metastasis correlates with the depth of invasion, which by
? Radial growth- horizontal spread within epidermis/superficial dermis
convention is the distance from the superficial epidermal granular cell layer
? lentigo maligna: indolent lesion on the face of older men
to the deepest intradermal tumor cells (Breslow thickness)
? Superficial spreading: (MC) sun-exposed skin
?
?
Warning signs: ABCDE (1) asymmetry; (2) irregular borders; and (3)
Acral/mucosal lentiginous melanoma: unrelated to sun exposure
variegated color, (4) increasing diameter, and (5) evolution
? Vertical growth -appearance of a nodule & correlates with metastatic
potential
? Marker- HMB-45 (Tendon clear cell sarcoma & Angiomyolipoma)
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Endocrine
system
Colloid goitre
Thyroiditis: Inflammation of the thyroid gland
(1)Hashimoto thyroiditis: autoimmune disease that results in destruction of the
thyroid gland and gradual and progressive thyroid failure
(2) Granulomatous (de Quervain) thyroiditis is a self-limited disease, probably
secondary to a viral infection, and is characterized by pain and the presence of a
granulomatous inflammation in the thyroid.
(3) Subacute lymphocytic thyroiditis often occurs after a pregnancy
(postpartum thyroiditis), typically is painless, and is characterized by lymphocytic
inflammation in the thyroid.
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Hashimoto's thyroiditis
Hashimoto's thyroiditis
? Most common cause of hypothyroidism in Iodine-sufficient areas
? Most common clinically apparent cause of chronic thyroiditis
? M:F 1 : 10-20
-
? Genes involved: CTLA4 & PTPN22
? C/F: Painless enlargement of thyroid + hypothyroidism
? HPE: Lymphocytic infiltration of the gland, well-developed germinal
centers, atrophic thyroid follicles, H?rthle cell metaplasia or oxyphil
change (Hallmark)
Grave's disease
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Thyroid Ca
Papillary Ca
Microscopic hallmarks
? Branching papillae with a fibrovascular stalk
? Nuclear features: Hallmark of diagnosis
? Orphan Annie eye nuclei (clear or empty appearing ground-glass appearance),
? Pseudo-inclusions" ? invaginations in cytoplasm- appearance of intranuclear
inclusions or intranuclear grooves.
? Psammoma bodies (Absent in follicular and medullary Ca)
? Lymphatic invasion is common
Follicular Ca Thyroid
Gross: Single well circumscribed or widely
infiltrative nodule
Microscopically:
? Small follicles containing colloid, Hurthle
cell or oncocytic variant: cells with
abundant eosinophilic cytoplasm,
? Capsular &/or vascular invasion is the
sign of carcinoma & differentiates
follicular adenoma ,
? Lymphatic spread is uncommon
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Medullary Ca Thyroid
Pheochromocytoma
? Neuroendocrine neoplasm derived from the
parafollicular cells, or C cells, of thyroid
? MEN syndrome 2A or 2B or familial
medullary thyroid carcinoma,
Microscopy
? Polygonal spindle-shaped cells form nests,
trabeculae and follicles
? Acellular amyloid deposits (A cal)
? Tumor Markers: Calcitonin, serotonin, ACTH,
and vasoactive intestinal peptide (VIP)
Pheochromocytoma
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This post was last modified on 03 August 2021