Etc includes certain antigens that may have been masked by formalin
TECHNIQUES OF THE FROZENGood frozen section technique is learned gradually and only through experience. The resident shouldquestion the staff freely and attempt to observe all steps closely at first. He/she then should do asmany things as possible and practice as much as possible. The steps of frozen section pathology areas follows:1. Gross Tissue ExaminationThis step is probably the most important step and unfortunately is one that many pathologists havenot yet learned. With practice one can become adapt at predicting what a biopsy will show on thebasis of its gross appearance, i.e., fibroadenomas of the breast have a characteristic whorledappearance; scirrhous breast cancer is retracted, stellate, and gritty.The pathologist obtains gross dues not from just looking at the tissue, but also from feeling it andcutting it, i.e., soft or gritty. The pathologist records all gross expressions, i.e., size, adhesions,weight, similar to the recording of microscopic features.2. Proper Communication With The SurgeonsThis step is equally important as #1 and should occur either simultaneously with #2, before, or slightlyafter, but before any tissue is frozen.The intercom is located in the frozen section suite; the room where the surgeon is operating will beobtained from the Pathology Department secretary transmitting the request for frozen section.A list of operating room procedures appear the day before the planned surgery, and it is theresponsibility of the resident and staff to be familiar with each case in advance. This means knowingwhat tissues have been removed previously, reviewing any previous diagnoses that our departmenthas on file, and reviewing all previous slides on the patient This is important because the presentprocedure may be related to previous ones. This "research" Is the pathologist's equivalent of themedical history.Example: A patient with a history of osteogenic sarcoma of the leg develops pulmonary nodules.Obviously, a comparison of the pulmonary material with the original material is essential indetermining whether the pulmonary lesions are metastases or separate lesions.After each case is thoroughly researched in advance, often there are additional questions and step #2is for this purpose. Consider the possibility of obtaining microbiological cultures before contaminatingthe specimen. (Special research studies may also require sterile handling of tissues.) Considerpreparing touch preps. When relevant, ink margins before cutting the specimens.Based on steps #1 and #2 two critical decisions are made: Is a frozen section indicated and if so,what areas of the tissue should be frozen? The answer to this second part is often difficult, but isbased on the question being asked and the pathologist's gross impression. Obviously, in a breastbiopsy the pathologist should freeze the most suspicious areas.3. Embedding The TissueThe selected piece of tissue is then placed on a metallic holder and must be oriented a certain way sothat the future section will reveal proper spatial relationships, this orientation depends on the questionbeing asked. Sometimes orientation is not important; at other times it is of paramount importance.The tissue is embedded in OCT mounting medium and is then placed either in cooled 2-methylbutane or the cryostat machine where it is properly frozen.4. CryostatThe machine, which cuts the tissue, is the cryostat. Certain things should be routinely checked in theoperation of this machine:a) TemperatureThe temperature should be at -20°F for most tissues. For tissues with a large fat component, -40°F isoptimal. This temperature is critical for optimal sectioning• Too high, i.e., -10°F and the tissue will not stay frozen and firm and will not cut crisp.• Too cold, i.e., -50°F and the tissue will crumble and become powder. The Ideal tissueshould cut like butter, smooth and in one piece.b) Blade sharpness and angleThe blade should be sharp and should be changed approximately once every 2 weeks. A dull bladecuts dull. Equally important is the blade angle. There is an optimal angle between blade and tissue:• Too steep an angle and the tissue will crumble like it was too cold.• Too shallow, then two things will happen. The section will alternately skip and not cutand then it will cut, but too thick.This brings us to thickness and thinness of sections. In the rear of the machine is a device foradjusting thickness of sections. Ideal sections should be between 3 and 6 microns. But if the angle istoo shallow even with the machine set at 3 microns, sections greater than 12 microns will beproduced. If the blade angle is optimal, clean, thin intact sections should be obtained serially, i.e., withevery cut.When the tissue is cut the pathologist has the option of using a plastic tissue plate for ensuring thatthe tissue does not get folded, or manually knocking the tissue off the knife with a small brush. One'sexact technique will vary with experience and individual preference. The tissue is picked up onto aslide by direct contact, taking care to avoid folds.5. StainingOnce the tissue is on the slide it can be either air-dried or fixed in methanol. This depends on whichstaining procedure will be used. There are several stains available in the frozen section room andeach has certain advantages.Advantage DisadvantageHematoxylin and Eosin • Looks similar to permanentsection staining • Takes approximately 3 minutesToluidine Blue • Takes 10-20 seconds • Different appearance thanpermanentsGiemsa • Takes 10-20 seconds • Different appearance thanpermanents• Stains most cells with mucincontainingcells •Pneumocystis Stain • Rapid Toluidine Blue /"rapid"approx. 1 hour •The choice of stain depends on what the pathologist is trying to demonstrate. The resident shouldpractice all the stains and gain experience with their use.The step-by-step procedures for each stain are listed in the operating room and in the histology roomand are again summarized here.6. Interpreting The Frozen SectionThe results of one's labor now come to a climax when the resident and staff sit at the double-headedmicroscope and discuss the slide and render a diagnosis.Since rapid diagnosis takes precedence over everything else in the operating room, oftentimesadditionaldiscussion and questions occur after the diagnosis has been rendered. The resident,however, should arrive at his/her own diagnosis and question the staff person without any hesitation.7. ControlsIn all science, controls are necessary. Since pathology is not an exact science, controls cannot beexact, but an attempt is made to check our frozen section accuracy. The tissue, which is frozen, issubmitted for permanents and labeled "frozen section control." This should be kept separate from theother additional tissue submitted for permanents. In this way, the pathologist has a limited check onhis frozen. If anything shows up on the permanents that is substantially different than the frozen, thesurgeon or doctor taking care of the patient should be notified immediately.GENERAL PATHOLOGY AND SUMMARYThe pathologist should always be conservative with frozen section, but accurate. A diagnosis ofinvasive breast carcinoma should be, in fact, invasive breast carcinoma with no hesitation if that iswhat the slide shows. Too many surgeons and too many pathologists imply an uncertainty in allfrozen section and take the philosophy of waiting for permanents. If the frozen section is definite, andmany are, a definite diagnosis should be made.In the cases that are uncertain, it is here that a conservative approach should be employed. It isalways better to call a malignant disease "benign" that it is to call a benign disease "malignant.” Thisis because a diagnosis of malignancy carries with it a definite and irreversible action, i.e.,mastectomy, whereas a benign diagnosis can always be revised after more thorough review.As in so many thins, experience is no substitute for knowledge, but knowledge alone is no substitutefor experience. It takes years of frozen section experience to become a good diagnostic frozensection pathologist, and the resident should not be discouraged at first, but instead be encouraged toask the advice of the staff for help and assistance in the frozen section room.
IDC Mammary Duct Ectasia : There was plenty of fibrous tissue and inflammatory cells… We found atypical cells which could have been of inflammatory origin.. Its fine to be on a false negative side than a false positive side.. Fortunately the patient already had a mastectomy done n wasn’t because of frozen.False negatives :Inflammatory lesion IDC In this case there was only necrosis and inflammation And we were unable to locate malignant cells in the frozen section which led to this False negative2. Lobular hyperplasia IDC In this case, there were atypical cells in the frozen section, but not to the extent that one can call it an IDC The lobular hyperplasia was present but not atypical.. So, IDC wasn’t give on the frozen but it was of course communicated them to give final diagnosis on paraffin section.. ???ISNT THIS A DEFERRED CASE??
False negatives:Boderline Pap Ser Neopl Serous pap cystadenocarcinomawe had a non representative sample…The focus of malignancy was not in the area sampled…BoderlineEptumou MucinousCystadenocarcinomaOn frozen, in this case, clearcut evidence of invasion wasn’t found..But there was an evidence of layering with atypia…It was after multiple sections that we could find in paraffin the malignancy..Pap Ser Cystadenoma Serous micropap carcinoma: This was a similar case which appeared benign on frozen but turned out to be malignant in paraffin when multiple sections were given…DEFERRED DIAGNOSIS: We have a system here for two consultants to sign a frozen.. And when there is a controversy, well, we generally prefer to wait for paraffin.. This this was exactly what was done in this case…There was a cyst and a nodule…Cyst appeared benign and was given so…The nodule did show anisonucleosis and hyperchromatic nuclei…But eventually what we got on paraffin was clear cell carcinoma of ovary…!
False negative : Benign neoplasm Acinic cell carcinoma This was a similar case of the sample being non representative : In the sections we gave, we saw well formed glands But we learnt that it was malignant on paraffin when we gave multiple sections.Deferred Diagnosis: This was one of the very tricky cases that we had.. The patient had a long standing history of a lump, a neck swelling And here there was a strong clinical suspicion of malignancy, What happened on frozen was: Because of dense inflammation, the epithelial elements showed a considerable amount of atypia…And so confusion prevailed as to whether call it benign or malignant.. So we asked them to wait for paraffin..thats how this was a deferred diagnosis….
Ileocecal mass: Well, here what we actually received, wasn’t a mass…The tissue on frozen showed only some mononuclear cells within the muscle layer..and wasn’t looking like a lymphoma… But on paraffin, well it turned out to be NHLNasal mass: The sample was non representative…
Good easy fast comparable with other studies and our reports are also sameIntraoperqtie findings should be communicatedFrozen section diagnosis is very useful and highlyaccurate procedure. Gross inspection, sampling bypathologist, frozen complemented with cytologicaland histological review and intimal cooperation withsurgeon, good communication between surgeon andpathologist can avoid certain limitations and providerapid, reliable, cost effective information necessary foroptimum patient care.
Oral paper at apcon 2012 comparative study of frozen section diagnoses with histopathology.dr.arpan
1. To establish the presence and nature of a lesion2. To determine the adequacy of surgical margins3. To establish whether the tissue obtained contains diagnosable material.
1. Rapid2. Demonstration of fats, lipids, etc1. Costly2. Not as satisfactory as paraffin sections3. Stressful
1. Proper Communication with the Surgeons2. Gross Tissue Examination3. Cryostat • Temperature • Blade sharpness and angle4. Staining5. Interpreting the frozen section6. Counterparts of frozen are processed for paraffin to check our accuracy
Cases taken from S.S.G. Hospital, BarodaInstrument used Cryostat (Leica CM 1850)Period of Study July 2007 – June 2012No. of cases 117
Organs submitted for frozen sections & thedistribution of malignancies diagnosed in paraffin section No. of No. of Organ Submitted Cases malignancies Breast 29 16 Nervous system 2 0 GIT 14 6 Thyroid gland and 6 0 Parathyroid Ovary and FT 24 9 UB and Male Genital 5 5 Tract
Organs submitted for frozen sections & the distribution of malignancies diagnosed in paraffin section No. of Organ Submitted No. of Cases malignancies Pancreas 1 0 ENT 11 8 Hepatobiliary 2 2 Skin 3 3 Lymph Node 8 3 Uterus and Cervix 7 3 Bone 1 0 Salivary gland 2 1 Soft tissue 2 1
No. of False False Organ Accuracy cases positives negativesBreast 29 1 2 89.66GIT 14 0 1 92.86Ovary and FT 24 0 3 87.50ENT 11 0 1 90.91Salivary gland 2 0 1 50.00
Site Frozen diagnosis Final diagnosis Mammary DuctBreast IDC Ectasia
Site Frozen diagnosis Final diagnosis Breast Inflammatory lesion IDC Lobular hyperplasia Breast IDC with atypical cellsIleocecal mass margin Inflammatory lesion Non Hodgkins lymphoma Boderline Papillary Serous papillary Ovary Serous Neoplasm cystadenocarcinoma Boderline Epithelial Mucinous Ovary tumor Cystadenocarcinoma Papillary Serous Serous micropapillary Ovary Cystadenoma carcinomaNasal Mass Inflammatory lesion Non Hodgkins lymphomaSubmandibular gland Benign neoplasm Acinic cell carcinoma
Site Frozen diagnosis Final diagnosis Cyst : Benign Ovarian Cyst Clear cellOvary and FT Nodule : Anisonucleosis, Carcinoma Hyperchromatic Nuclei of Ovary ? Inflammatory Non specificSubmandibular ?Malignant sailadenitis gland Wait for paraffin