Artefacts Produced by Normal Saline When Used as a Holding Solution for Biopsy Tissues in Transit

Abstract

Oral surgeons, surgeons and dentists carrying out small biopsy procedures on an out-patient basis have been frequently sending poorly stored biopsy tissues to the Departments of Oral Pathology of various dental colleges, wherein the tissues were being stored in normal saline and then transferred to formalin. Such tissues often show abnormal cellular and architectural changes, which pose a challenge to diagnosis, especially when the histopathologist is not aware that the tissue was stored in normal saline for some time. We wanted to know the extent of artefactually induced cellular and architectural changes in tissues that were transported in normal saline and received by us, based on the duration for which they were held in normal saline. Normal oral soft tissue was subjected to storage in normal saline for periods varying from 1 to 36 h, before being fixed in 10 % formalin. Soft tissue specimens were collected during routine surgical extractions and each was cut into six parts. One was transferred immediately to formalin as control and other bits kept in normal saline for intervals of 1, 3, 12, 24, and 36 h before fixing in formalin. A comparative photographic analysis was carried out to analyze the histopathological changes. The tissues kept in normal saline before fixation underwent various changes. In no way should normal saline be used, even for a short time, to store and transport excised tissue; it is imperative that such tissues be placed immediately in a proper fixative like 10 % formalin.

Clinicians’ role in the occurrence of oral biopsy artifacts as a potential diagnostic dilemma

“…19,32 Fixation stops these chan ges. 19,32,33 It maintains the integrity of cells and their chemi cal components, 34 preserving the tissue in conditions like when alive. 13,34 The time interval between the surgical removal of the sample and its immersion in a proper fix ative is referred to as the ischemia or hypoxia time, 34,35 which is associated with the activation of tissue enzymes, autolysis, and the degradation of proteins, DNA and RNA.…”

“…34 Tap water, 3 distilled water or saline are occasionally used for tissue fixation. 18,20,33 Tissues fixed with these solutions often show abnormal cellular or structural changes 33 that can pose a challenge for the correct diag nosis of the lesion. 33 Saline does not cause any fixation at all 19 and should not be used even for a short time.…”

“…18,20,33 Tissues fixed with these solutions often show abnormal cellular or structural changes 33 that can pose a challenge for the correct diag nosis of the lesion. 33 Saline does not cause any fixation at all 19 and should not be used even for a short time. 33 The immersion of the specimen in saline causes the bizarre appearance of epithelial cells, which can suggest malig nancy.…”

“…33 Saline does not cause any fixation at all 19 and should not be used even for a short time. 33 The immersion of the specimen in saline causes the bizarre appearance of epithelial cells, which can suggest malig nancy. 5 Antiseptics, mouthwashes or local anesthetic solutions are also inappropriate for tissue fixation.…”

Oral Pathology in Clinical Dentistry: A systematic approach

“…Studies have shown that if biopsy is placed in saline for 1 h, and then transferred to formalin fixative, distortion of tissues (cell vacuolization in basal layer of epithelium and reduced cohesiveness of collagen fibers in the connective tissue) take place, making the diagnosis problematic. [5] In case the dental surgeon believes that immunofluorescence would be necessary (for vesiculobullous lesions and/or autoimmune disorders), it is better to take two tissue samples: one in formalin for routine staining and the other in Michel's solution for direct immunofluorescence. [6] The container should be tightly sealed and properly labeled with patient's name, age, gender and site.…”