Grossing Flashcards
THYMUS: Describe grossing procedure
- Record outer dimensions and weight of the specimen (normal 15-30g)
- Examine outer surface for adherant structures
- Ink the outer surface
- Serially section
- Describe any lesions including size, colour, relationshiop to capsule, circumscribed/infiltrative, calcification, necrosis, hemorrhage
- Describe uninvolved thymus (cystic, nodular, gritty, uniform) and relative proportions of fat and thymic parenchyma
- Examine for lymph nodes
- Put some tissue in RPMI for flow, remaining in formalin
- Submit 4-6 blocks of tumor w/ relationship to capsule/thymus, margins, uninvolved thymus
THMUS: What IHC stains are helpful in distinguising thymic carcinoma from other sites?
- CD5: epithelial cells from thymic carcinomas + vs thymomas, invasive thymomas, other carcinomas are NEG.
- CD99, TdT, CD19, CD1a: positive in thymomas/invasive thymomas, but not in carcinomas or non-thymic lesions. Stain up the complement of immature cortical thymocytes.
THYMUS: What are the expected gross findings for the following conditions:
a. normal thymus
b. myasthenia gravis
c. thymoma
d. thymic carcinoma
e. germ cell tumor
f. lymphoma
Normal thymus: atrophic, tan lobules thymic parenchyma separated by fibrous septae w/ abundant fat. May see Hassell’s corpuscles.
Myasthenia gravis: normal in size, slightly enlarged otherwise unremarkable.
Thymoma: Encapsulated, solid, yellow/gray, divided into lobules by fibrous septae. May have cystic degeneration. Possible invasion into soft tissue.
Thymic carcinoma: Hard, white, with hemorrhage and necrosis. No broad fibrous septae, clear invasion into soft tissue.
Germ cell tumor: Solid, homogenous, yellow-tan
Lymphoma: lobulated, fleshy-white
THYMUS: What items are required for synoptic reporting?
- Histologic type (A, AB, B1, B2, B3, thymic carcinoma & subtypes)
- Tumor extension (lung parenchyma, pleura, pericardium, diaphragm)
- Margins
- Treatment effect
- LVI
- lymph nodes
- stage: Modified Masaoka Stage for thymomas, TNM staging thymic carcinoma
THYMUS: Describe the Masaoka Clinical staging for thymomas
Stage I: Grossly and microscopically encapsulated (includes microscopic invasion into, but not
through, the capsule)
Stage IIa: Microscopic transcapsular invasion
Stage IIb: Macroscopic capsular invasion
Stage III: Macroscopic invasion of neighboring organs
Stage IVa: Pleural or pericardial dissemination
Stage IVb: Hematogenous or lymphatic dissemination
THYMUS: Describe the TNM staging for thymic carcinomas
pT0: No evidence of primary tumor
pT1: Tumor completely encapsulated
pT2: Tumor invades pericapsular connective tissue
pT3: Tumor invades neighboring structures, such as pericardium, mediastinal pleura, thoracic wall,
great vessels, and lung
pT4: Tumor with pleural or pericardial dissemination
pNX: Regional lymph nodes cannot be assessed
pN0: No regional lymph node metastases
pN1: Metastasis in anterior mediastinal lymph nodes
pN2: Metastasis in other intrathoracic lymph nodes, excluding anterior mediastinal lymph nodes
pN3: Metastasis in scalene and/or supraclavicular lymph nodes
THYROID: Describe the grossing procedure
- Weight and dimensions of R lobe, L lobe, isthmus
- Oriented by: concave posterior surface, tapering lobes superior, isthmus inferior
- Examine for parathyroid glands (brown-yellow ovoid bodies)
- Ink outer surface (3 colours preferred)
- Serially section from superior to inferior
- Describe each lesion (size, colour, consistency, necrosis, hemorrahge, encapsulation, relationship to capsule)
- Describe remaining parenchyma:
- Normal: red-brown beefy
- Pale: lymphocytic thyroiditis
- Amber and plastic-like: amiodarone
- Black: minocycline
- Describe adjacent soft tissue, submit lymph nodes
- Submit entire capsule of follicular lesions, 1/cm of papillary CA, 1 section/each different looking nodule in nodular hyperplasia.
- Submit 2 uninvolved thyroid sections/lobe, parathyroid tissue, lymph nodes
THYROID: What is the gross appearance of the following lesions:
- Adenoma
- Papillary carcinoma
- Follicular carcinoma
- Medullary carcinoma
- Anaplastic carcinoma
- Nodular hyperplasia
- Graves disease
Adenoma: Solitary, thinly encapsulated, pale tan-grey, soft & fleshy <3cm
Papillary carcinoma: 20-60% multicentric, size usually 2-3cm, white tan/granular, calcifications common. Rarely complete capsule.
Follicular: Solitary, usually thickly encapsulated, may have infiltration, hemorrahge, necrosis. Need to sample entire capsule for microscpic invasion.
Medullary carcinoma: Arise in middle/upper 1/3 of central lobe (where C cells lie), often multicentric, non-encapsulated but well-circumscribed. Soft, fleshy, grey/white/yellow. Size ranges from <1cm to entire gland.
Anaplastic carcinoma: Pale grey, firm, hemorrhage/necrosis. Widely Infiltrative.
Nodular hyperplasia: Enlarged, distorted, heterogenous nodularity. Some nodules appear encapsulated. Random scarring, hemorrhage, calcifications, cysts.
Graves: DIffusely enlarged, homogenous texture without noduels. Beefy red.
THYROID: Describe the grossing procedure for a prophylactic thyroidectomy
- Performed for history of familial medullary carcinoma (MTC, MEN2) or germ-line RET protoncogene mutations
- Examine entire middle-to upper 1/3 of lateral lobes for C-cell hyperplasia
- After serial sectioning submit representative sections from any gross lesions, lower/upper/isthmus
THYROID: What items are required for synoptic reporting?
- Procedure, specimen integrity, specimen size, specimen weight
- Tumor focality, tumor laterality, tumor size
- Histologic type, histologic subtype (for papillary, follicular)
- Margins, tumor capsule, tumor capsule invasion
- LVI, PNI, extrathyroid extension
- TNM staging
- Any additional parenchymal findings, parathyroid findings, C-cell hyperplasia
THYROID: Descibe situations in which capsular invasion is present for follicular carcinomas
- tumor totally transgresses the capsule invading beyond the outer contour of the capsule
- tumor clothed by thin (probably new) fibrous capsule but already extending beyond an imaginary (dotted) line drawn through the outer contour of the capsule
- satellite tumor nodule with similar features (architecture, cytomorphology) to the main tumor lying outside the capsule
- mushroom shaped bud completely transgressing fibrous capsule and grown out into surrounding thyroid
THYROID: Capsular invasion for follicular carcinoma
Capsular invasion: Focal, extensive, widely invasive (i.e. grossly visible)
THYROID: Describe situations qualifying for vascular invasion in follicular carcinomas
A. Bulging of tumor into vessels within the tumor proper does not constitute VI.
B: Tumor thrombus covered by endothelial cells in
intracapsular vessel is VI
C. Tumor thrombus in intracapsular vessel considered as VI since it is attached to
the vessel wall.
D: If not endothelized, tumor thrombus qualifies for VI because it is accompanied by a fibrin thrombus.
E: Endothelialized tumor thrombus in vessel outside the tumor capsule represents VI.
F: Artefactual dislodgement of tumor manifesting as irregular tumor fragments into vascular lumen unaccompanied by endothelial covering or fibrin thrombus DOES NOT COUNT AS VI
Extent: focal: < 4 vessels, extensive > 4 vessels
THYROID: Describe the criteria for invasion within follicular carcinoma
Vascular space invasion: blood vessels should be of venous caliber, located outside the tumor, within, or outside the capsule.
“minimally invasive” : capsular invasion but no vascular
invasion
THYROID: Define extrathyroidal extension (minimal and extensive)
minimal extrathyroidal extension : presence of carcinoma extending into perithyroidal tissues, ncluding infiltration of adipose tissue and skeletal muscle, as well as around (and into) sizable vascular structures and nerves
extensive extrathyroidal extension: extension into subcutaneous soft tissues; adjacent viscera, including the larynx, trachea and/or esophagus; the recurrent laryngeal nerve, carotid artery or mediastinal blood vessels.
THYROID: Describe the TNM staging
pT0 No evidence of primary tumor
pT1 2 cm or less, limited to thyroid
pT1a 1 cm or less, limited to the thyroid
pT1b >1 cm < 2 cm in greatest, limited to the thyroid
pT2 >2 cm<4 cm, limited to thyroid
pT3 >4 cm limited to thyroid or minimal extrathyroid extension
pT4a Moderately advanced disease. any size extending beyond the thyroid capsule to invade subcutaneous soft tissues, larynx, trachea, esophagus or recurrent laryngeal nerve
pT4b Very advanced disease. Tumor invades prevertebral fascia or encases carotid artery or
mediastinal vessels
*** All anaplastic are T4
pN1a Level VI (pretracheal, paratracheal and prelaryngeal/Delphian)
pN1b unilateral, bilateral or contralateral cervical (Levels I, II, III, IV, V) or retropharyngeal or superior mediastinal lymph nodes (Level VII).
THYROID: Describe the types of neck dissections that may accompagny a thryoidectomy
- Radical neck dissection
- Modified radical neck dissection, internal jugular vein and/or sternocleidomastoid muscle spared
- Selective neck dissection (SND), as specified by the surgeon
a. Supraomohyoid neck dissection
b. Posterolateral neck dissection
c. Lateral neck dissection
d. Central compartment neck dissection - Selective neck dissection (SND), as specified by the surgeon -“SND” with levels and sublevels
designated - Extended radical neck dissection, as specified by the surgeon
THYROID: Describe the lymph node levels of the neck
Level I.
- *Submental Group (IA)** (ant. digastric/hyoid bone)
- *Submandibular Group ( IB)** (post. digastric/mandible)
Level II.
Upper Jugular Group (Sublevels IIA and IIB)
(upper 1/3 int. jug. vein and spinal acc. nerve, from carotid bifurc. to hyoid/skull base)
(post. boundary is the post. border of the sternocleidomastoid muscle, anterior boundary is the lat.border of the sternohyoid muscle)
Level III. Middle Jugular Group
middle 1/3 of the int. jug. vein extending from the carotid bifurcation superiorly to the omohyoid muscle (surgical landmark)
Level IV. Lower Jugular Group
lower 1/3 int. jugular vein extending from the omohyoid muscle superiorly to the clavicle inferiorly.
Level V. Posterior Triangle Group (Sublevels VA and VB)
lower half of the spinal acc. nerve and the transverse cervical artery. The supraclavicular nodes are also included in this group. The post. boundary is the anterior border of the trapezius muscle, the
ant. boundary is the posterior border of the sternocleidomastoid muscle, inf. boundary clavicle
Level VI. Anterior (Central) Compartment
paratracheal nodes, precricoid (Delphian)
node, and the perithyroidal nodes, including the lymph nodes along the recurrent laryngeal nerve. The
superior boundary is the hyoid bone, the inferior boundary is the suprasternal notch, the lateral
boundaries are the common carotid arteries, and the posterior boundary by the prevertebral fascia.
Level VII. Superior Mediastinal Lymph Nodes
Metastases at Level VII are considered regional lymph node metastases
THYROID: Name 3 IHC stains that can be used in the diagnosis of papillary ca
- CK19
- Galectin 3
- HBME-1
THYROID: Name molecular mutations and associated histological subtypes of papillary CA of thyroid
RET/PTC1 translocations: 60% papillary carcinomas.
carcinoma with predominant papillary architecture and papillary microcarcinoma;
RET/PTC3 fusion: tall cell and solid variants, as well as to radiation-induced tumors.
BRAF mutation: can be seen from 30%-70% of papillary ca, esp. classic type, tall cell variant, Warthin-like, oncocytic type
RAS gene mutations/PAX8/PPAR translocation: follicular variant, rare to have RET/PTC or BRAF in this variant
PARATHYROID: Describe specimen grossing
- Weigh & record dimensions of each specimen
- Describe: color (brown-yellow), lesions, entire gland vs biopsy
- Normal weight: 27-33 mg men, 30-40 mg women
- any gland >50 mg is enlarged
- normal size 2x2x2mm
- either submit entirely or representative sections if large
PARATHYROID: What is the typical gross appearance of the following lesions:
- Adenoma
- Hyperplasia
- Carcinoma
Adenoma (85%): solitary lesion, >300mg, size 1-3 cm, loss of stromal fat and compression of normal gland
Hyperplasia (15%, mostly secondary): multiple glands, fat may be decreased, all enlarged to varying degrees.
Carcinoma (2%): large, >40 GRAMS, 2-6cm, firm, lobulated grey-tan mass adherant to soft tissue +/- apparent capsular invasion
PARATHYROID: What histologic features can help distinguish between adenoma, atypical adenoma, carcinoma?
- Relationship to surrounding tissue (adenomas encapsulated, carcionmas invade)
- Thick fibrous bands (present in carcinoma)
- Mitotic activity: <5/50 HPFs and ki <3% in atypical adenomas, >5/50 HPFs and ki >6% in carcinomas
- Perineural invasion: absent in adenoma
- Vascular invasion: absent in adenoma
- Necrosis: present in 1/3 of carcinomas
- Nuclear atypia: scattered in adenomas, marked pleomorphism with macronuclei in 1/2 of carcinomas
SOFT TISSUE: Name 5 features of a lipoma that raise the likelyhood of malignancy:
- large size >5cm
- infiltration into surrounding tissues
- Location in deep tissue/near spermatic cord
- History of recurrence
- Unusual gross appearance (white, homogenous, firm, fibrotic areas, attached tissue)
SOFT TISSUE: Describe the grossing protocol for a liopma
- Record size, thinly section for ususual findings
- Sample 1/cm and areas of varying appearance
- Consider touch preps or sending for FISH in cases of: deep seated location, unusual apperance, surgeon request
Retinoblastoma: How would you stage this tumor?
- Tumjor invades optic nerve head, past lamina cribrosa (so T3)
Diagnosis?
Retinoblastoma with clinical leukocoria
Diagnosis?
Retinoblastoma, endophytic growth
Diagnosis?
Retinoblastoma, extension into anterior chamber
In a retinoblastoma, What is the name of these structures?
Flexner-Winstersteiner rosettes.
Cells oriented around central lumen, no basement membrane at periphery, apically oriented
In a Retinoblastoma, what are these structures? Do they signify differentiation?
- Homer-wright rosettes, and do not signify differentiation
- Flexner-Wintersteiner rosettes and fleurettes imply differentiation
