Deep Surgical Margins Research Articles

Predictable tissue shrinkage during frozen section histopathologic processing for Mohs micrographic surgery.

When confronted with a histologic specimen that is appreciably smaller than the same tissue specimen immediately after acquisition, the Mohs surgeon is faced with two possibilities, namely that the tissue has either shrunken during laboratory processing or that the histologic specimen is incomplete due to the introduction of technical errors during embedding, cutting, or staining of the skin specimen. Because the entire objective of Mohs micrographic surgery is to precisely examine the entire surgical margin of skin specimens, the surgeon must be able to determine that any size discrepancies introduced during laboratory processing are not related to incomplete surgical specimens. Although there are anecdotal suggestions that skin, like other human tissues, undergoes some degree of shrinkage during routine frozen section processing, the exact nature and magnitude of this phenomenon has not been previously investigated. To quantify the degree of tissue shrinkage in Mohs micrographic surgical specimens processed with routine frozen sections and subsequent hematoxylin and eosin staining. A total of 117 Mohs surgery patients (135 cutaneous tumors) were prospectively enrolled. The dimensions of initial stage surgical specimens were determined after removal from the patient, after freezing in a mounting medium, after placement on a glass microscopic slide, and after hematoxylin and eosin staining. Statistical analyses were performed in order to determine the significance of any discrepancies in specimen sizes introduced during laboratory processing. Skin specimens processed by frozen section techniques during Mohs micrographic surgery undergo statistically significant alterations in length. On average the measurements of specimens at the conclusion of histologic processing were 11.6% shorter than the measurements of the same specimens obtained immediately after surgical excision. Tissue specimens obtained from the trunk or extremities showed a greater degree of tissue shrinkage (16.3%) than specimens obtained from the head and neck (10.2%). Our results support anecdotal suggestions that skin specimens do indeed shrink during frozen section processing. By realizing that frozen section specimens can be expected to show some slight degree of shrinkage, the Mohs surgeon can appreciate situations that might allow greater confidence that a smaller specimen is nonetheless representative of the entire lateral and deep surgical margins.

舌癌Ｔ１・Ｔ２症例の再発因子 臨床病理学的検討

Significant factors related to primary recurrence of T1/T2 carcinoma of the tongue and neck lymph node metastasis were analyzed with the use of logistic analysis in 108 patients. All patients had undergone Cot laser resection between March 1980 and April 1997. The factors analyzed included: (1) primary site of the carcinoma, (2) differentiation of squamous cell carcinomas, (3) diameter of the primary tumor, (4) absence/presence of perineural invasion of the primary tumor, (5) absence/presence of intravascular invasion of the primary tumor, (6) absence/presence of in-tramuscular invasion of the primary tumor, (7) depth of primary tumor invasion. (8) surgical margin of the resected primary tumor, and (9) absence/presence of irradiation. Significant risk factors for primary recurrence were a surgical margin of less than 4 mm and tumor coverage of the posterior third of the mobile tongue. A significant risk factor in neck lymph node metastasis was depth of primary tumor invasion of more than 4 mm, no other significant factors for the primary recurrence or regional recurrence were observed. The results suggested that a deep surgical margin of more than 10 mm was nesessary, and that if the primary lesion occupied the posterior third of the mobile tongue, an extended surgical resection was nesessary. In addition, if the depth of the primary tumor invasion is more than 4 mm, preventive modified radical neck dissection is recommended.

Three-dimensional assessment of surgical excision margins in skin tumor resection biopsies

A new technique for the assessment of adequacy of surgical margins of excision in skin tumor resection biopsies is described. The technique essentially consists of staining the whole fresh or fixed biopsy tissue in eosin followed by Mayer's hematoxylin. Following staining, the epidermal perimeter of the skin ellipse and the deep surgical margin can be assessed using a stereo-microscope. Should areas suspicious of inadequate excision be identified these may be confirmed by directed frozen or paraffin section.