Drug – bio-affecting and body treating compositions – Preparations characterized by special physical form – Web – sheet or filament bases; compositions of bandages; or...
Reexamination Certificate
2000-02-16
2003-05-06
Page, Thurman K. (Department: 1615)
Drug, bio-affecting and body treating compositions
Preparations characterized by special physical form
Web, sheet or filament bases; compositions of bandages; or...
C424S443000, C424S484000, C424S485000, C424S486000, C424S487000, C424S488000, C424S078030, C424S448000
Reexamination Certificate
active
06558694
ABSTRACT:
BACKGROUND OF THE INVENTION
The present invention relates to the treatment of human melanoma, basal and squamous cell skin cancer, and a variety of other skin tumors and skin diseases. More particularly, the present invention relates to unit dose packaging of a zinc chloride mixture and used in a dosage specific applicator for the treatment of these skin diseases.
Melanoma is a potentially fatal form of skin cancer, usually appearing as a black or dark brown mole. The conventional treatment of cutaneous melanoma has been excision with a deep and wide margin of normal appearing tissue surrounding the tumor depending on the depth and thickness of the cancerous mole. However, microscopic satellite sites potentially occurring in the otherwise normal appearing skin surrounding the melanoma may be disturbed, and host resistance may be reduced following the excision of the melanoma. A decrease in host resistance may result in the appearance of cancer in distant sites of the body (metastases). (Smolle, J. et al,
Does Surgical Removal of Primary Melanoma Trigger Growth of Occult Metastases? An Analytical Epidemiological Approach.
Dermatologic Surgery, November, 1997). Cancer metastases can cause death of the patient. Although it is common to excise a margin of tissue surrounding the tumor, it is well known that increasing the size of the surgical margin to greater and greater extent does not affect survival rate.
Adjuvant therapy has been recommended for melanoma patients in whom clinical and histopathological parameters indicate a high risk of relapse. Interferon alpha
2
B has been approved by the United States Food and Drug Administration for treatment of such high-risk melanomas. However, the survival from high-risk melanomas remains poor, and additional modalities are needed. Clinical evidence shows that the pre-surgical application of zinc chloride paste improves the prognosis of melanoma.
Zinc chloride was discovered by Sir Humphry Davy of Bristol, United Kingdom, in 1815. It was used for the treatment of cancer by Canquoin of Paris and by Bougard of Brussels in the early part of the nineteenth century. Zinc chloride is a very potent chemical which deeply penetrates and kills tissue.
While a research assistant in the department of zoology at the University of Wisconsin, Dr. Frederic E. Mohs, founder of the American College of Mohs Micrographic Surgery and Cutaneous Oncology, observed that the injection of zinc chloride into cancerous tissue not only caused tissue necrosis (cell death), but, additionally, the microscopic structure of the killed tissue was retained as if the tissue had been excised and immersed in a fixative, or histologically preserving solution. Dr. Mohs developed an anti-skin cancer paste containing zinc chloride and the escharotic bloodroot plant,
Sanguinaria canadensis.
The formula is as follows: Stibnite (alpha, beta-Diphenylethylene 80-mesh sieve), 40 g;
Sanguinaria canadensis,
10 g; and zinc chloride, saturated solution, 34.5 mL (zinc chloride 45% by weight).
Since 1941, Dr. Mohs has published a textbook and numerous articles on the successful treatment of skin cancer and melanoma using this zinc chloride paste. Dr. Mohs referred to the paste as “zinc chloride fixative paste” and the surgery as “chemosurgery” or “fixed-tissue micrographic surgery”. For the treatment of melanoma, Mohs utilized a layer by layer excision technique in addition to in situ fixation of the tumorous tissue with zinc chloride fixative paste. In fixed-tissue surgery, a clinically apparent melanoma is first treated with zinc chloride fixative paste prior to any biopsy or debulking procedure. The next day, a layer of fixed tissue is excised and frozen histologic sections are made for microscopic examination to confirm the clinical diagnosis of melanoma. The melanoma is then excised layer-by-layer, with each successive layer first fixed in situ, then conservatively removed for microscopic scanning of the entire undersurface utilizing frozen histologic sections cut horizontally from the bottom of the excised specimens. The edges of the specimens are color coded by the application of dyes for precise orientation as the sections are scanned under the microscope. The zinc chloride paste is reapplied as necessary until a melanoma-free plane has been reached. An extra margin of surrounding tissue is then removed by zinc chloride fixed-tissue surgery to encompass satellite deposits that may be present in the surrounding skin lymphatics.
In 1977, Mohs published data on 103 consecutive patients with mainly advanced melanomas treated with zinc chloride fixative paste (64% Clark's level V lesions, 20% regional lymph node involvement). The 5-year cure rate was compared with a series of melanomas treated conventionally by surgical excision alone at the Massachusetts General Hospital, and stratified by Clark's level of invasion. In the Clark's melanoma classification system there are five levels. Clark's I being the most superficial and V being the deepest invasion of the skin and penetration into fatty tissue under the skin. Both studies were completed in 1968. In the conventional surgery series, all the melanomas were primary tumors without regional lymph node metastases, and the incidence of level V invasion was only one-sixth that of the zinc chloride fixative cases. Despite a 20% incidence of nodal metastases and a six times greater incidence of level V melanomas in the fixed tissue series, a significant (p=0.003) one and a half times improvement in five year survival was achieved using zinc chloride fixative paste. (Mohs, FE:
Chemosurgery for melanoma.
Arch Dermatol 133: 285-291,1977; Brooks, N A:
Fixed
-
tissue micrographic surgery in the treatment of cutaneous melanoma,
J. Dermatol Surg. Oncol. 1992; 18: 999-1000.)
Similar results have been found with the common skin cancers, basal cell and squamous cell carcinoma. In 1986, Dr. Almeida Goncalves and Dr. Ricardo Azevedo published their experience using a zinc chloride paste with a group of patients which consisted of 179 basal cell carcinomas and 33 squamous cell carcinomas of varying diameters. All patients had more than five years follow-up and no tumor persistence or recurrence was observed. (Goncalves J C A,
Chemosurgery without systematized microscopic control for malignant skin tumors—A new simplified technique.
Skin Cancer, 1986; 1: 137-150). This study continued until 400 basal cell and squamous cell skin cancers had been treated. Only one persistence had occurred resulting in a cure rate of 99.7%, which is much higher than the reported cure rate for curettage and desiccation, the most commonly used method for the treatment of basal and squamous cell skin cancer (Goncalves, J C A and Azevedo, R B R.
An attempt at reducing pain in cancer patients treated by chemosurgery without systemized microscopic control.
Skin Cancer, 1998; 13: 145-161.Salasche, S J.
Status of curettage and desiccation in the treatment of primary basal cell carcinoma.
J American Acad of Dermatology, 1984; vol 10: 285-287).
While the use of zinc chloride chemosurgery has been shown to produce remarkable life-saving results, these treatments have not been grasped by the medical community. This has been due, in part, to the lack of understanding of the manner in which zinc chloride prevents relapse in cancer and increases survival rates, the difficulty in following the Mohs procedure, and the potency and instability of zinc chloride pastes. A detailed discussion of why these treatments have been overlooked and underestimated follows.
The Mohs Technique is Difficult to Perform
The Mohs method is a laborious and time consuming process, requiring the repetitive examination of multiple layers of zinc chloride fixed tissue. Furthermore, Mohs taught of the use of dressings which are complicated and difficult to apply for the application of zinc chloride paste to the skin. In the Mohs' dressing technique, first a layer of dry cotton is applied over the zinc chloride paste to help hold it in place on the skin, then a gauz
Brooks Leslee S.
Brooks Norman A.
Ghali Isis
Kelly Bauersfeld Lowry & Kelley LLP
Page Thurman K.
LandOfFree
Zinc chloride unit dose packaging, applicator, and method of... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Zinc chloride unit dose packaging, applicator, and method of..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Zinc chloride unit dose packaging, applicator, and method of... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3076615