Management of superficial basal cell carcinoma: focus on imiquimod

Early clinical experience with a degraded 4 MeV electron beam in radiotherapy of superficial basal cell carcinoma

The most common non-melanoma skin cancer is basal cell carcinoma (BCC). Surgery is the gold standard treatment but also non-surgical alternatives are needed. The purpose of this work was to present the early clinical experiences of degraded 4 MeV electron beam as a treatment method for superficial BCC. Twelve patients underwent two weeks radiation therapy treatment with either 5 × 7 Gy or 2 × 12 Gy. There were no significant differences in treatment outcome with different fractionations or lesion locations. The degraded beam method is a safe and valid non-surgical solution for suitable patients with superficial lesions.

Management of keratinocyte carcinoma - Special considerations in the elderly

Keratinocyte carcinomas (KCs) are now an epidemic in The United States of America, especially in elderly patients. KCs, including basal cell carcinoma and squamous cell carcinoma, can lead to disfigurement and occasionally death. However, the lower mortality rate associated with KC compared with melanoma allows for increased flexibility in the selection of treatment. Flexibility in treatment is particularly important in the elderly given that this patient population often has medical comorbidities that should be considered. These patients may have multiple KCs, higher risk tolerance to recurrence, and different concerns about cosmetic outcomes compared with their younger counterparts. We review treatment options for KCs and how the selection of each option may affect the elderly patient.

Colloidal (-)-epigallocatechin-3-gallate vesicular systems for prevention and treatment of skin cancer: A comprehensive experimental study with preclinical investigation

Skin carcinogenesis is a common malignancy affecting humans worldwide, which could benefit from nutraceuticals as a solution to the drawbacks of conventional skin cancer treatment. (-)-epigallocatechin-3-gallate (EGCG) is a promising nutraceutical in this regard; however, it suffers chemical instability and low bioavailability resulting in inefficient delivery. Therefore, EGCG encapsulation in ultradeformable colloidal vesicular systems, namely: penetration enhancer-containing vesicles (PEVs), ethosomes and transethosomes (TEs) for topical administration has been attempted in this study to overcome the problems associated with the use of free EGCG. The prepared vesicles were characterized for their entrapment efficiency, TEM visualization, chemical compatibility, antioxidant properties, ex-vivo skin deposition, photodegradation and physical stability after storage. Most of the prepared vesicles exhibited reasonable skin deposition and preservation of the inherent antioxidant properties of EGCG with good physical stability. EGCG-loaded PEVs and TEs exhibited an inhibitory effect on epidermoid carcinoma cell line (A431) in addition to reduced tumor sizes in mice, confirmed with histopathological analysis and biochemical quantification of skin oxidative stress biomarkers; glutathione, superoxide dismutase and catalase, as well as lipid peroxidation. EGCG PEVs succeeded in offering an effective delivery system targeting skin cancer, which is worthy of further experimentation.

Potent and Selective Inhibitors of MTH1 Probe Its Role in Cancer Cell Survival

Recent literature has claimed that inhibition of the enzyme MTH1 can eradicate cancer. MTH1 is one of the "housekeeping" enzymes that are responsible for hydrolyzing damaged nucleotides in cells and thus prevent them from being incorporated into DNA. We have developed orthogonal and chemically distinct tool compounds to those published in the literature to allow us to test the hypothesis that inhibition of MTH1 has wide applicability in the treatment of cancer. Here we present the work that led to the discovery of three structurally different series of MTH1 inhibitors with excellent potency, selectivity, and proven target engagement in cells. None of these compounds elicited the reported cellular phenotype, and additional siRNA and CRISPR experiments further support these observations. Critically, the difference between the responses of our highly selective inhibitors and published tool compounds suggests that the effect reported for the latter may be due to off-target cytotoxic effects. As a result, we conclude that the role of MTH1 in carcinogenesis and utility of its inhibition is yet to be established.

Review of natural compounds for potential skin cancer treatment

Most anti-cancer drugs are derived from natural resources such as marine, microbial and botanical sources. Cutaneous malignant melanoma is the most aggressive form of skin cancer, with a high mortality rate. Various treatments for malignant melanoma are available, but due to the development of multi-drug resistance, current or emerging chemotherapies have a relatively low success rates. This emphasizes the importance of discovering new compounds that are both safe and effective against melanoma. In vitro testing of melanoma cell lines and murine melanoma models offers the opportunity for identifying mechanisms of action of plant derived compounds and extracts. Common anti-melanoma effects of natural compounds include potentiating apoptosis, inhibiting cell proliferation and inhibiting metastasis. There are different mechanisms and pathways responsible for anti-melanoma actions of medicinal compounds such as promotion of caspase activity, inhibition of angiogenesis and inhibition of the effects of tumor promoting proteins such as PI3-K, Bcl-2, STAT3 and MMPs. This review thus aims at providing an overview of anti-cancer compounds, derived from natural sources, that are currently used in cancer chemotherapies, or that have been reported to show anti-melanoma, or anti-skin cancer activities. Phytochemicals that are discussed in this review include flavonoids, carotenoids, terpenoids, vitamins, sulforaphane, some polyphenols and crude plant extracts.

Thickness of superficial basal cell carcinoma (sBCC) predicts imiquimod efficacy: a proposal for a thickness-based definition of sBCC

BACKGROUND

Basal cell carcinoma (BCC) is the most common malignancy in the white population. It is an important driver of healthcare costs and causes significant morbidity. Topical imiquimod is a good noninvasive treatment alternative for surgical excision in superficial BCC (sBCC). However, there are currently no uniform histological definitions of sBCC. A definition based on tumour thickness might be a good alternative.

OBJECTIVES

To determine whether tumour thickness in sBCC is a predictor of treatment failure.

METHODS

We retrospectively examined 127 histological biopsy specimens of sBCC treated primarily with imiquimod five times a week for 6 weeks. Mean follow-up was 34 months (range 3-91). Recurrence was evaluated clinically with histological verification.

RESULTS

Among nonrecurrent cases the median tumour thickness was 0·26 mm (range 0·09-0·61), while for recurrent cases the median tumour thickness was 0·57 mm (range 0·41-1·41, P < 0·0001). Among lesions ≤ 0·40 mm in thickness, none recurred, whereas for lesions > 0·40 mm the recurrence rate was 58% (P < 0·0001).

CONCLUSIONS

We recommend the use of tumour thickness to define the superficial pattern in pathology reports for BCC as this can help to determine treatment response of sBCC to imiquimod.