58. Basal Cell Carcinoma of the Eye Area

Introduction Because of the potential consequences of failure to cure an invasive malignancy of the eyelid, most dermatologist and surgeons of today lean heavily toward the use of microscopically controlled removal techniques; favorite of such procedures being Mohs micrographic technique. Surgeons not trained in Mohs might utilize frozen sections at the time of surgery. Fixed tissue histologic analysis of the margins of excised tissue may be used by other surgeons. The consensus is that some form of microscopic analysis of the margins is highly preferred to assure much as possible the certainty of a clear surgical margin after tumor removal. Cryosurgery remains a viable option for the treatment of eyelid neoplasms and benign conditions such as trichiasis. Therapeutic Alternatives Besides the treatments described in the introduction, radiation, electrodessication and curettage, and combinations such as surgical removal followed by radiation of the perimeter are all methods that while still providing a very high cure rate, do not provide histologic control of the margin after treatment of the tumor. Cryosurgery Cryosurgery has been used widely and extensively throughout the world for the destruction of malignant tissue. The method of LN application by either direct spray or probe technique is well accepted as suitable for the destruction of malignant cells. Other cryogens are typically not utilized because of their lesser abilities to rapidly reduce tissue temperature or cost and handling requirements. LN is readily available and reasonably inexpensive throughout the world. Metodology (How I Do It) The standard and accepted method of LN cryosurgery involves either spray or probe application to the surface of the lesion until a margin of tissue 3 mm removed from its clinical margin is reduced to a −40 °C, as measured by a thermocouple. When −40 °C is registered at the selected margin of treatment, the delivery of LN is stopped. The frozen ice ball is then allowed to thaw in unassisted fashion. After the lesion has thawed in its entirety, the sequence is repeated. This method of double freeze slow thaw cycle is generally accepted principle for the maximal destruction of tissue (Figs. 58.1, 58.2, 58.3, 58.4, and 58.5). Fig. 58.1 Basal cell carcinoma of the eyelids before cryosurgery Fig. 58.2 Post-op at 1 week Fig. 58.3 Post-op at 6 weeks Fig. 58.4 Post-op at 6 months Fig. 58.5 Post-op at 5 years × × × × × Success Rates In most instances cryosurgery accomplishes cure rates in the range of 95–99 % for all cutaneous basal cell carcinomas (BCC). Although cryosurgery is very effective for the destruction of BCC, most physicians with experience in the treatment of periocular lesions would limit its use for those lesions with well-defined margins and reasonably small diameter. Fraunfelder and other would suggest that the selection of lesions best be limited to those BCC of less 1 cm in diameter and of nodular or nodular-ulcerative type with sharp clinical margins [1]. BCC with infiltrative characteristics have a lower cure rate by virtue of the difficulty in clinically defining the presumed margins of the tumor. Without reasonably defined clinical margins, it is difficult to determine the desired endpoint of the cryosurgical destructive isotherm. By carefully selecting smaller, nodular BCC and by the use of appropriate technique, a cure rate equal to, or in excess of 97 % is reasonably expected. Two significant contributions to the field of cryosurgery of BCC on the eyelids were published recently; a series of 781 lesions averaging less than 1 cm, in 768 patients treated over 30 years and prospectively followed for over 10 years – those operated on the first 20 years of the study, and for at least a year the rest – showed recurrences in only three patients [2]; a series of 220 patients followed for at least 5 years showed recurrences in only 5.1 % after a first attempt and of 0.6 % after a second cryosurgery [3]. Complications Significant eyelid and periocular edema is a natural and accepted consequence of cryosurgery in the periocular zone. The edema may reach such level in the immediate postoperative days as to occlude vision. This can be reduced through the use of postoperative systemic steroids and cold compresses to the area. The edema typically resolves within 7 days. If a tumor involves the full thickness of the lash margin, a rounded defect may occasionally occur. Loss of lashes within the treated part is to be expected. Ectropion may occur but not commonly. If innercanthal lesions are treated, punctal and canalicular occlusion may occur. Avoidance of that area is strongly recommended. Hyperthophic scars occur highly uncommonly. Ectropion as result of scar retraction may happen and is more common if the lesion treated is located in an inferotemporal location. Most of the scars resulting from cryosurgery are cosmetically acceptable. Rarely, pseudoepitheliomatous hyperplasia develops in the months following treatment; typically, it resolves spontaneously. Should regrowth suggestive of recurrence occur, a repeat biopsy should be promptly done. Healing after cryosurgery typically requires 4–8 weeks, depending upon the size of the lesion; it may be associated with edema, serous discharge, and scar formation if the wound is allowed to remain dry. Depigmentation may be a problem particularly after healing in darkly pigmented skin. Conclusion Although the complications from cryosurgery may seem an obstacle, the good cosmetic results and high cure rates in the hands of well-trained cryosurgeons, make the treatment, in most instances, highly satisfactory.

Medicine Matters Oncology

58. Basal Cell Carcinoma of the Eye Area

Abstract