Basal cell carcinoma is the most frequently occurring cancer in humans. It arises from the basal layer of the epidermis and grows slowly over multiple years.
Key risk factors for developing BCCs have been recognized, such as ultraviolet radiation, fair complexion, chronic arsenic exposure, ionizing radiation, personal or family history for BCC and genetic predisposition [3, 4].
In our case, the patient had no personal or family history of BCC and no prior exposure to ionizing radiation or other carcinogens. The location of the carcinoma on the scrotum in our case renders ultraviolet exposure an unlikely culprit.
Basal cell carcinoma has multiple histological subtypes, and they can be classed according to their risk of recurrence to low-risk and high-risk subtypes. The nodular, superficial, fibroepithelial, pigmented, and infundibulocystic BCC are classified as low-risk subtypes, while the infiltrative, micronodular, morpheaform, basosquamous, and BCC with sarcomatoid differentiation are considered as the higher-risk subtypes [5]. However, histological patterns may overlap.
Nodular BCC is the most common variant, characterized clinically by rolled edges, surface telangiectasia, and a central ulcer, giving rise to what is known as the rodent ulcer.
The micronodular variant is an aggressive type of BCC that is liable to recur and hard to eradicate. It occurs most frequently in the head and neck area [6]. Clinically, micronodular BCC typically presents as a poorly defined infiltrated flat lesion that rarely ulcerates.
Approximately, 80–85% of BCC occur on the head and neck, while 15% develop on the trunk [7]. According to a classic review conducted by Rabbari and Mehregan, less than 0.5% of BCCs were located in the genital area [8].
We searched the Pubmed database using the Medical Subject Headings (MeSH) Terms: “Carcinoma, Basal cell” AND “scrotum”.
Only 14 cases were reported over the past twenty years; the patients’ details, tumor morphology, and microscopic classification are summarized in Table 1.
Table 1
Case reports published in the past twenty years of BCC arising on the scrotum. Abbreviations: LN: lymph nodes, NF: neurofibromatosis.
Ref | Year | Authors | Country | Patient Age | Morphology | Pigmentation | Size( cm) | Microscopic type | Metastasis | Months to presentation | Carcinogen exposure |
9 | 2000 | Takahashi, et al. | Japan | 49 | Hyperkeratotic erythematous plaque | No | 1 | - | No | 12 | No |
10 | 2000 | Vandeweyer, et al. | Belgium | 66, 71, 58, 74 | Ulcer with pearly border, erythematous plaque | No | 0.5, 1.5, 0.9, 1.5 | Solid BCC | No | 9 | History of radiation exposure |
11 | 2002 | Chave, et al. | UK | 69 | Nodule with central ulcer | Side pigmentation | 1.5 | - | No | 3, 6 | No |
12 | 2002 | Ribuffo, et al. | Italy | 75 | Ulcer | No | - | - | Perineal skin | 60 | No |
13 | 2004 | Izikson, et al. | USA | 77 | Ulcerated nodule | Variegated | 4 | Nodular BCC | No, recurrence + | - | Coal tar, asbestos, machine oil, sulfur, hydraulic fluid, (smoker) |
14 | 2005 | Kinoshita, et al. | Japan | 80 | Ulcerated nodule | No | 2.5 | - | LN, recurrence | 96 | No |
15 | 2008 | Ouchi, et al. | Japan | 54 | Pedunculated nodule | Yes | 1.7 | Polypoid BCC | No | 6 | No |
16 | 2008 | Rao, et al. | India | 75 | Ulcerated nodule | Yes | 4 | - | No | 24 | No |
17 | 2011 | Jianwei, et al. | China | 74 | Ulcer with pearly border | No | 2 | Nodular BCC | No | 612 | Benzene |
18 | 2014 | Li, et al. | China | 61 | Eroded plaque, rolled border | No | 4 | Nodular BCC | No | 18 | No |
19 | 2016 | Delto, et al. | USA | 69 | Fungating verruciform mass, flat lesion | No | 10 | - | No | - | NF, (smoker) |
20 | 2016 | Hernandez, et al. | Spain | 50 | Eroded exophytic tumor | No | 1 | Solid BCC | No | 12 | Asbestos |
21 | 2018 | Padoveze et al. | Brazil | 87 | Perlaceous tumor with telangiectasias | No | 2.5 | Nodular BCC | No | 6 | No |
22 | 2020 | Han et al. | China | 74 | Nodule | No | 2 | Superficial BCC | No | 144 | No |
| 2021 | Current case | Syria | 55 | Nodule | Yes | 0.7 | Micronodular BCC | No | 24 | No |
The average age of patients was 67.6 years old (49–87 years) and the most commonly reported clinical morphology was the ulcerated nodule with pearly borders. The average age of the lesion at presentation was 6.5 years (3 months-51 years).
Unlike our case, the reported lesions were infrequently pigmented at presentation (4 cases).
There were no reported cases of micronodular BCCs arising from the scrotal dermis, our article is thus the first reported case of such a rare presentation in the literature.