Basal cell carcinoma (BCC) incidence is increasing, particularly among adults under the age of 40 years. Pigment-related characteristics are associated with BCC in older populations, but epidemiologic studies among younger individuals and analyses of phenotype-genotype interactions are limited. We examined self-reported phenotypes and melanocortin 1 receptor gene (MC1R) variants in relation to early-onset BCC. BCC cases (n=377) and controls with benign skin conditions (n=390) under the age of 40 years were identified through Yale's Dermatopathology database. Factors most strongly associated with early-onset BCC were skin reaction to first summer sun for 1 hour (severe sunburn vs. tan odds ratio (OR)=12.27, 95% confidence interval (CI)=4.08-36.94) and skin color (very fair vs. olive OR=11.06, 95% CI=5.90-20.74). Individuals with two or more MC1R non-synonymous variants were 3.59 times (95% CI=2.37-5.43) more likely to have BCC than those without non-synonymous variants. All host characteristics and MC1R were more strongly associated with multiple BCC case status (37% of cases) than a single BCC case status. MC1R, number of moles, skin reaction to first summer sun for 1 hour, and hair and skin color were independently associated with BCC. BCC risk conferred by MC1R tended to be stronger among those with darker pigment phenotypes, traditionally considered to be at low risk of skin cancer.

Basaloid follicular hamartoma (BFH) is a rare benignadnexal tumor with variable clinical presentation.We report a case of a 64-year-old man, whopresented with an incidental finding of a 3mmhyperpigmented macule on his cheek. Dermoscopyrevealed a structureless blue lesion. Histopathologyexamination showed interconnecting lobules andcords of bland pigmented epithelial cells within thedermal stroma, with the presence of pseudohorncysts. The lesional cells were faintly positive for Bcl2on immunohistochemical staining. These findingswere consistent with basaloid follicular hamartoma.Histological differential diagnoses include benignlesions such as trichoepithelioma, and malignantlesions such as basal cell carcinoma (BCC).

Basal cell carcinoma (BCC) can be a component of a collision tumor in which the skin cancer is present at the same cutaneous site as either a benign tumor or a malignant neoplasm. However, BCC can also concurrently occur at the same skin location as a non-neoplastic cutaneous condition. These include autoimmune diseases (vitiligo), cutaneous disorders (Darier disease), dermal conditions (granuloma faciale), dermal depositions (amyloid, calcinosis cutis, cutaneous focal mucinosis, osteoma cutis, and tattoo), dermatitis, miscellaneous conditions (rhinophyma, sarcoidal reaction, and varicose veins), scars, surgical sites, systemic diseases (sarcoidosis), systemic infections (leischmaniasis, leprosy and lupus vulgaris), and ulcers. The relationship between the BCC and the coexisting non-neoplastic condition may be coincidental or possibly related to the development of the BCC; alternatively, the development of the BCC may be unrelated to the coexisting non-neoplastic conditions and secondary to either a Koebner isomorphic response or a Wolf isotopic response in an immunocompromised district of skin. This paper reviews several of the case reports and studies that describe the association of BCC with these non-neoplastic cutaneous conditions.

Oculocutaneous albinism is a genetically heterogeneous, autosomal recessive group of disorders characterized by a generalized decreased or absence of melanin pigment in the eyes, hair, and skin. These patients have a greater sensitivity to UV radiation and a predisposition to skin tumors, mainly squamous cell carcinoma and basal cell carcinomas, and to a lesser extent malignant melanomas. Melanoma can be one of the most challenging cancers to diagnose in patients with albinism. We report an uncommon clinical presentation of melanoma, an amelanotic melanoma in the right supraciliar region in a patient with oculocutaneous albinism. The clinical presentation was an erythematous, scaly and ill-defined plaque. The skin biopsy revealed a lentigo maligna melanoma. Amelanotic melanomas are one of the two most difficult to diagnose subtypes of melanoma, together with the nevoid type. Melanoma in oculocutaneous albinism patients are often amelanotic, which makes their clinical diagnosis very difficult. These patients should be examined in the dermatology department at least once a year and it is recommended to have a high index of suspicion.

Non-invasive imaging devices are currently being utilized in research and clinical settings to help visualize, characterize, anddiagnose cancers of the skin. Speckle-variance optical coherence tomography (svOCT) is one such technology that offers considerable promise for non-invasive, real time detection of skin cancers given its added ability to show changes in microvasculature. We present four early lesions of the face namely sebaceous hyperplasia, basal cell skin cancer, pigmented actinic keratosis, and malignant melanoma in situ that each display different important identification markers on svOCT. Up until now, svOCT has mainly been evaluated for lesion diagnosis using transversal (vertical) sections. Our preliminary svOCT findings use dynamic en face (horizontal) visualization to differentiate lesions based on their specific vascular organizations. These observed patterns further elucidate the potential of this imaging device to become a powerful tool in patient disease assessment.

Background

Sex or gender disparity in skin cancer has been documented for a long time at the population level. UV radiation (UVR) is a common environmental risk for all three major types of skin cancer: cutaneous melanoma (CM), basal cell carcinoma (BCC) and cutaneous squamous cell carcinoma (cSCC). The underlying mechanism for sex disparity has been largely attributed to sex-differentiated behaviour patterns related to UVR. Non-UVR factors such as intrinsic physiological differences have been suggested but remain understudied.

Aims materials and methods

This review summarizes and compares the known sex differences in three skin cancer types with regard to body site distribution and age influence.

Results

We found a similar age-dependent sex difference pattern in CM and BCC. Specifically, CM and BCC tend to show higher incidence in young women and old men, with a switching age around menopause. The switching age suggests involvement of sex hormones, which has shown controversial influence on skin cancers at epidemiological level. Literatures regarding sex hormone receptors for oestrogen, androgen and progesterone are summarized for potential explanations at molecular level.

Discussion

Overall, more and more evidence suggests non-UVR factors such as sex hormones play critical roles in skin cancer (especially CM and BCC), yet solid population and molecular evidence are required. Incidences of skin cancer are increasing which suggests limited effect for the current UVR-avoidance prevention methods.

Conclusion

Fully understanding the causes of sex disparities in incidence is necessary for developing a comprehensive prevention strategy.

We report a case of a 60-year-old man who was a former cigar smoker with a slow-growing, large exophytic left shoulder mass (15 cm in diameter) and later found to have left axillary lymphadenopathy. Fine needle aspirate biopsy of the left shoulder mass revealed squamous cell carcinoma (SCC). However, pathology of the enlarged left axillary lymph node was reported as metastatic adenocarcinoma. The patient underwent surgical resection of the shoulder mass which comprised of SCC (>95%) and adenoid basal cell carcinoma (BCC) as a second component of the tumour. The BCC had identical histology as the metastatic carcinoma in the left axillary lymph node. Therefore, diagnosis was revised as cutaneous collision tumour with metastatic BCC. Six months later following adjuvant radiation therapy, the patient was diagnosed with metastatic BCC in the right lung. Stereotactic body radiation therapy (SBRT) and a selective hedgehog pathway inhibitor vismodegib were given with only limited efficacy. Clinical trial registration number NCT03132636.