FROZEN SECTIONS

Frozen sections FRCPath 2020 Dr. Leena Joseph Consultant Histopathologist MFT

• “Primum Non Nocere” (First do no harm)

Frozen sections

If a definitive diagnosis is not possible then judicious deferral or a generic diagnosis is the preferred route.

Communicate effectively.

Juan Rosai 7th Edition of Ackerman's Surgical Pathology

On frozen sections"one of the most important and difficult procedures a pathologist performs during his practice.

It requires experience, knowledge of clinical medicine and pathology, the capacity to make quick decisions under pressure, good judgment, an attitude that is conservative but not excessively so, and a keen awareness of the limitations of the method".

Frozen sections

A valuable tool in the intraoperative management of clinical problems mostly tumours.

Indications • To avoid unnecessary surgical procedures • Primary diagnosis when there is no preoperative diagnosis • Staging, if this is not possible by other means • Assessment of surgical margins

Frozen sections

• Tests competence and confidence • Ability to deal with suboptimal samples • Ability to work under time pressure • Ability to deal with uncertainty • Surgeons need answers • Expectations are not always realistic • Fence sitting is uncomfortable in the end

M61

Case 1 -CLINICAL HISTORY: Lt upper lobe nodule PET active.

Case 1

Diagnosis??

Diagnosis Frozen section diagnosisCaesating inflammatory lesion There is no evidence of malignancy Paraffin sectionsCaseating granulomatous lesion –AFB+ve • Relatively straight forward • Lymphoid follicles with germinal centres maybe mistaken for atypical cells

Lung –Frozen sections • Benign or malignant • ? Tumour ?inflammatory • Tumour ?Primary ?metastatic • Primary ?small cell ?non small cell Ask for further clinical information if necessary.

Beware of your limitations. Don’ t go too far!!!

Case2

M40 -Patient has MEN1. Has multigland hyperparathyroidism.

• Specimen A superior parathyroid • Specimen B inferior parathyroid

CASE2

Specimen B

Diagnosis?

A:Parathyroid tissue in keeping with a parathyroid adenoma B:Thyroid tissue

Case 2

Relatively easy Differentiate between normal, adenoma, hyperplasia.

What are the other glands like? You must ask!!

Pitfalls - Lymph node, Thyroid or thymic tissue.

Specimen “C”

Thymic tissue

Case3

F76 Large right breast Ca suspicious lymph node . FNA C2 Sentinel node for frozen section analysis

CASE3

Diagnosis

Case 3 Metastatic carcinoma • No need to specify primary site unless asked.

• Most lymph nodes will be normal or metastasis • Watch out for sinus histiocytosis which may look like carcinoma in frozen sections • Low grade lymphoma – unfair!

Case4 M 76 Previous Ca rectum.

Nodule right upper lobe for frozen section ?metastasis

CASE 4

Diagnosis?

Case 4 • Frozen section Diagnosis- Mucinous carcinoma

Paraffin tissue- primary mucinous carcinoma of lung (TTF1+ve)

• Relatively straightforward • Chronic inflammation and fibrosis may be mistaken for malignancy especially if prominent epithelial cells present

• Benign or malignant • ? Tumour ?inflammatory

Lung –Frozen sections

• Tumour ?Primary ?metastatic • Primary ?small cell ?non small cell Ask for further clinical information if necessary.

Beware of your limitations. Don’ t go too far!!!

Case 5

CLINICAL HISTORY: F59 -Chest pain, cough. O/E looks v.well.

- Multiple varying sized shadows both lungs. All PET +ve.

Biopsy (A) (L) lower lobe for frozen section

CASE 5

Case 5 M62- Bx lung Non caseating Granulomatous lesion No evidence of malignancy.

• Potential infectious aetiology- appropriate measures to reduce the risk of exposure to self and others • Send tissue for microbiological examination

Case 6 • F76 Ca Breast- Axillary node- ?involved

CASE 6

Diagnosis??

Frozen sections – case 6

• Female 51- Lymph node biopsy • Negative • Watch out for sinus histiocytosis which may look like carcinoma in frozen sections • Most lymph nodes will be normal or metastasis • Low grade lymphoma – unfair!

Case 7

75 F grade 1 TCC bladder densely adherent right lower ureter.

Bx right ureter.

CASE 7

Case 7 • ??Diagnosis

Case -7 M75 Ureteric margin Frozen section diagnosis-Inflammation with reactive atypia.

Paraffin sections- H&E – Chronic uretritis with Von Brunns nests

 Frozen sections of ureteric /urethral margins to look for insitu or invasive carcinoma- may limit surgical reconstruction if involved  Pitfalls- Inflammation Von Brunns nests

Case 8

F63 Hx of asbestos exposure (L) pleural effusion (L) base pleural/lung nodule biopsied

CASE8

DIAGNOSIS?

Case8 • Frozen section diagnosis- Fungal ball • Paraffin sections Aspergilloma • Relatively easy • Test of confidence

Case9

F74 Recurrent SCC. Frozen section Skin/mucosa right nose

CASE9

Diagnosis?

Diagnosis • Squamous cell carcinoma invading deep, cartilage uninvolved.

• Relatively easy • Test of confidence

Case10

• F33 yrs Right ovarian cyst ? dermoid, normal markers.

Diagnosis

Diagnosis • “The section shows a tumour composed of polygonal cells with cytonuclear pleomorphism, ill defined cytoplasmic boundaries and vacuolated cytoplasm. This is an unusual and difficult lesion with a differential diagnosis that includes steroid cell tumour and clear cell carcinoma.

The final diagnosis is deferred to paraffin sections.”

Case11 • F46 Donor kidney – small yellow lesion seen at the upper pole of frozen section prior to possible transplantation

Case 11

• Frozen answer = Adrenal tissue no evidence of neoplasia • Paraffin section = Adrenal rest

KIDNEY FROZENS

• Donor nodules and cysts – Clear cell lesions ? Carcinoma - remember adrenal and Xanthogranulomatous PN. • Frozens on larger lesions sometimes used to exclude/confirm Urothelial origin which would lead to nephroureterectomy • Frozens on partial nephrectomy tumour margins more common now but not without difficulties

Case12

• – Male: 69 year: Tongue tumour – margin ?involved Tongue -base bx

DIAGNOSIS?

Case12 • Diagnosis: Soft tissue with skeletal muscle and multiple mucous glands and small lingual tonsillar tissue

CASE 12 • Relatively easy • Epithelial islands may be mistaken for malignancy • Lymphoid aggregates may look malignant -Remember anatomy of site!!!

Case • M 64.

• Known adenocarcinoma stomach.

• Multiple small white nodules on surface of liver at laporotomy ?

Metastases

• Frozen section of nodules.

Case 4 • Bile duct hamartoma/ Von Meyenburg complex • Small 1-2mm white nodules on liver surface • Variable number of bile ducts embedded in a fibrous stroma.

• Represent ductal plate malformations of peripheral interlobular bile ducts “pollard willow”branching pattern

Frozen sections of liver nodules -Metastatic lesions -inflammatory/granulomatous lesions -microhamartomas -focal nodular hyperplasia usually solitary associated with oral contraceptive use ,central scar + -nodular regenerative hyperplasia- non neoplastic nodules of hyperplastic hepatocytes arranged in plates more than one cell thick not delimited by fibrous septae -Liver cell adenoma

Frozen sections • This section provides an opportunity to display important qualities • Less confrontational than before when double header was used • If you know the answer be confident and make your case • Detailed description is less important than the bottom line • Don’t Defer unless you have to