Neoplasias

Question 1

A male patient presents with an asymptomatic hyperpigmented patch of about 15 centimeters over his right shoulder, extending to the right upper arm. The lesion was first noticed 2 years ago and has been gradually increasing in size. A skin biopsy shows acanthosis, mild hyperkeratosis, increase pigmentation in the basal layer, and increased follicular units. What condition may be associated with this diagnosis?

1. Accessory scrotum
2. Cataracts
3. Fibrous dysplasia
4. Subungual fibromas

Answer 1

1 - Accessory scrotum

• The diagnosis is Becker melanosis. It is a rare disease that primarily occurs in the peripubertal period, more commonly in males than females.
• Becker melanosis may be associated with other findings related to ectodermal abnormalities and is known as Becker nevus syndrome.
• Smooth muscle hamartomas, ipsilateral hypoplasia of the breast, pectoral muscle, and fat, limb hypertrophy, adrenal gland hyperplasia, and accessory scrotum can be seen in Becker nevus syndrome.
• Both conditions are considered sporadic but congenital and familial cases have been reported.

Question 2

A 45-year-old black male computer programmer presents to the clinic with a nonpainful black streak within the nail of his left index finger. He denies any significant medical history and takes no medications other than an occasional aspirin. He denies a history of skin cancer in himself or his family. His vital signs are within normal limits. He specifically denies any trauma to his fingers. The black streak was first noticed last year and has gotten longer and wider. The solitary band of pigmentation measures 4 mm at its proximal base and narrows to 2 mm wide at the distal free edge. Dermoscopy examination reveals multiple parallel pigmented bands of varying widths that are gray to black in color. No globules are seen. Which of the following is the best course of action?

1. Take a nail clip biopsy of the distal nail plate for fungal culture
2. Photograph the lesion and plan follow up examination in six months
3. Refer for subungual nail matrix biopsy of the proximal portion of the streak
4. Plan nail avulsion and shave biopsy of the distal 2/3 of the nail bed streak

Answer 2

3 - Refer for subungual nail matrix biopsy of the proximal portion of the streak

• Single streaks carry a higher risk of melanoma than multiple bilateral streaks.
• Benign subungual pigmented streaks typically do not leak pigment into the proximal nail fold and maintain less than a 3mm width throughout their length.
• Subungual hematomas are more likely to be transverse rather than longitudinal.
• Longitudinal pigmented nail streaks wider than 3mm are much more likely to represent subungual melanoma.

Question 3

A 60-year old farmer presents with several lesions on his head, neck, abdomen, and nose. He says he has had these skin lesions for many years but they do not seem to be going away. He has been a farmer all his life and has no other pertinent medical history. On physical exam, there are two lesions that appear waxy and have a central depression. The edges have a pearly appearance. Excisional biopsy of one of the lesions reveals that it is a malignancy. This type of malignancy has often been linked to intake of what metal?

1. Mercury
2. Arsenic
3. Lead
4. Chromium

Answer 3

2 - Arsenic

• While the majority of basal cell cancers are due to sun exposure, they can also occur as a result of ionizing radiation.
• X-ray therapy was once used to treat acne and resulted in basal cell cancers.
• Exposure to arsenic has also been linked to basal skin cancer of note it is seen in sun-exposed and non-sun exposed parts of the body.
• Treatment of chronic arsenic poisoning is possible. British anti-lewisite is prescribed in doses of 5 mg/kg up to 300 mg every 4 hours for the first day, then every 6 hours for the second day, and finally every 8 hours for 8 additional days. Blood, hair, nails, and urine may be tested for arsenic; however, these tests cannot foresee possible health outcomes from the exposure. Long-term exposure and consequent excretion have been linked to bladder and kidney cancer in addition to cancer of the liver, prostate, skin, and lungs.

Question 4

A 79-year-old woman presents with a one-month history of fatigue, recurrent fevers, diarrhea, and a florid but asymptomatic skin eruption initially on the thorax and then spreading to face, back and extremities. Her admission blood work revealed severe pancytopenia, while a skin biopsy and subsequent histologic evaluation of the lesions revealed infiltrated erythematous papules, nodules, and occasional plaques. She is a lifetime smoker but has been in good health, has no medical conditions and is not on any regular medications. What is the most likely diagnosis?

1. Erythema multiforme
2. Drug reaction
3. Leukemia cutis
4. Sweet syndrome

Answer 4

3 - Leukemia cutis

• Leukemia cutis may present as erythematous nodules/papules, macules, plaques or ulcers.
• The lesions of leukemia cutis are typically asymptomatic.
• The lesions may predate the onset of hematological findings, occur in conjunction with or after the onset of hematological/bone marrow findings. In some cases, they may represent relapse of leukemia in an individual in remission.
• The histological findings typically present with a dermal perivascular involvement. However, due to the variety of patterns that leukemia cutis takes, histopathologic confirmation can be challenging. Thus, prompt clinicopathologic and immunological correlation is necessary.

Question 5

A 17-year-old male patient presents with extensive skin furrows over his parietal scalp. The patient had a history of brownish lesions over the same site which was present since birth and had gradually increased in size. Over time, the skin over the scalp became progressively convoluted. There are no lesions elsewhere on the body. The patient does not have any other skin or systemic disease. A skin biopsy from the lesion showed clusters of nevus cells in the dermis with significant fibrosis. Which of the following is the most likely diagnosis?

1. Acanthosis nigricans
2. Neurofibromatosis
3. Nevus lipomatosis
4. Intradermal nevus

Answer 5

4 - Intradermal nevus

• The description of the scalp lesions is suggestive of cutis verticis gyrata.
• Secondary cutis verticis gyrata can be due to a number of dermatological conditions like neurofibromatosis, intradermal nevus, nevus lipomatosis, and acanthosis nigricans
• A skin biopsy is often required to pinpoint the exact underlying skin condition.
• In this case, the presence of a pre-existing lesion since birth and the histopathology strongly indicate the possibility of intradermal nevus.

Question 6

A 42-year-old female was diagnosed with the fibrosarcomatous variant of dermatofibrosarcoma protuberans (DFSP) and subsequently underwent wide local excision. About a year later, a red nodule recurred at the scar. A skin biopsy confirmed local recurrence of DFSP. Shortly after that, a lung mass was detected on a chest CT scan and was proven to be metastatic DFSP following wedge resection. Fluorescent in situ hybridization (FISH) analysis demonstrated the presence of the t(17;22)(q22;q13) translocation, resulting in the PDGFB/COL1A1 fusion protein. Which treatment would be most appropriate?

1. Repeat wide local excision and adjuvant radiation therapy
2. Mohs micrographic surgery and radiation therapy
3. Mohs micrographic surgery and imatinib mesylate therapy
4. Mohs micrographic surgery and vismodegib therapy

Answer 6

3 - Mohs micrographic surgery and imatinib mesylate therapy

• DFSP often exhibits subclinical extension, making the tumor prone to local recurrence, especially when treated with wide local excision alone.
• Mohs micrographic surgery (MMS) is the best surgical treatment option for most cases of DFSP. MMS is a surgical technique which ensures complete circumferential and deep margin assessment.
• An interprofessional approach should be used for metastatic disease. Imatinib mesylate, a tyrosine kinase inhibitor, is an oral medication which is FDA-approved for adults with unresectable, recurrent, or metastatic DFSP. Studies have shown that DFSPs with the t(17;22)(q22;q13) translocation respond well to imatinib mesylate therapy. Vismodegib is a drug used for metastatic basal cell carcinoma.
• Testing for the t(17;22) translocation should be performed prior to starting imatinib mesylate therapy. This can be completed via fluorescent in situ hybridization (FISH) or reverse transcription polymerase chain reaction (RT-PCR).