eMedicine Specialties > Oncology > Carcinomas of the Skin

Lentigo Maligna Melanoma: Differential Diagnoses & Workup

Author: Winston W Tan, MD, Assistant Professor of Medicine, Mayo Medical School; Consulting Staff, Mayo Group Practices
Coauthor(s): Antony J Charles, MD, Fellow, Department of Hematology and Oncology, Mayo Clinic, St Luke's Hospital; Broc L Pratt, MD, Consulting Staff, Metrolina Plastic Surgery, Charlotte, North Carolina; B Todd Heniford, MD, Assistant Clinical Professor, Department of General Surgery, University of North Carolina; Chief, Division of Minimal Access Surgery, Carolinas Medical Center
Contributor Information and Disclosures

Updated: Mar 4, 2009

Differential Diagnoses

Other Problems to Be Considered

Solar lentigo
Pigmented actinic keratosis
Seborrheic keratosis
Common acquired nevi
Dysplastic nevi

Workup

Laboratory Studies

  • Patients with low-risk melanomas, less than 1 mm thick, do not routinely need laboratory studies. Most centers order liver function tests and lactose dehydrogenase (LDH) as part of the initial laboratory evaluation.

Imaging Studies

  • Chest radiograph is done by most institutions in patients with low-risk disease.
  • A PET scan, staging CT scans, or MRI can be performed for patients with node-positive disease or symptoms suggestive of metastasis, to determine extent of disease.

Other Tests

  • Dermoscopy is a newer tool available to help the dermatologist distinguish benign from malignant lesions. It is a hand-held instrument that magnifies the skin lesion 10 times to enable more accurate diagnosis.

Procedures

  • Skin biopsy
    • Ideal biopsy of lesions should include full-thickness skin extending to the subcutaneous fat.
    • Avoid superficial skin biopsy by shaving, scissors excision, or curettage because these techniques do not allow for assessment of tumor thickness, which is important for prognostication and treatment planning.
    • A better choice would be excisional biopsy with a narrow margin of normal-appearing skin, which can usually be performed on lesions unless the result would be disfiguring, in which case incisional biopsy is considered reasonable. Incisional biopsy is also indicated for lesions that are too large for complete excision.
    • The type of biopsy does not influence patient survival or rate of metastasis. Previous concerns that incision into a melanoma promotes its dissemination have been allayed. The excisional biopsy specimen may be obtained by elliptical excision, saucerization, or punch biopsy, if the lesion is small enough. The specimen should include a portion of subcutaneous fat to ensure that accurate microstaging can be determined.
  • Lymph node biopsy
    • Sentinel lymph node biopsy is done to assess regional lymph node involvement and to decide on adjuvant therapy. It is indicated in all melanoma patients except stage 0 or stage 1A, that is, patients with a lesion less than 1 mm.
    • If metastasis is present, a full nodal dissection is done to fully stage the disease.

Staging

Lentigo maligna is melanoma in situ.

Lentigo maligna melanoma is melanoma.

The American Joint Committee on Cancer (AJCC) 2002 Tumor, Node, Metastases (TNM) staging for melanoma uses tumor size, rather than invasion, and ulceration to stage the tumor.

  • Tumor staging is as follows (for the stages below, a indicates without ulceration, and b indicates with ulceration):
    • Tx - Primary tumor cannot be assessed (eg, regressed primary)
    • Tis - Melanoma in situ
    • T1 - Less than 1 mm
    • T2 - 1.01-2.0 mm
    • T3 - 2.01-4.0 mm
    • T4 - Greater than 4.0 mm
  • Nodal staging is as follows (for the stages below, a indicates micrometastasis [clinically occult], and b indicates macrometastasis [clinically apparent]):
    • N - Nodal involvement
    • N1 – One node
    • N2 - 2-3 nodes
    • N3 - 4 nodes or more
  • M indicates metastasis.

More on Lentigo Maligna Melanoma

Overview: Lentigo Maligna Melanoma
Differential Diagnoses & Workup: Lentigo Maligna Melanoma
Treatment & Medication: Lentigo Maligna Melanoma
Follow-up: Lentigo Maligna Melanoma
References
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References

  1. Jemal A, Siegel R, Ward E, et al. Cancer statistics, 2006. CA Cancer J Clin. Mar-Apr 2006;56(2):106-30. [Medline].

  2. Rigual NR, Popat SR, Jayaprakash V, et al. Cutaneous head and neck melanoma: the old and the new. Expert Rev Anticancer Ther. Mar 2008;8(3):403-12. [Medline].

  3. Liu V, Mihm MC. Pathology of malignant melanoma. Surg Clin North Am. Feb 2003;83(1):31-60, v. [Medline].

  4. American Cancer Society. Facts and Figures for 2008. Available at http://www.cancer.org/downloads/STT/2008CAFFfinalsecured.pdf. Accessed 10/21/2008.

  5. Rigel DS, Friedman RJ, Kopf AW. The incidence of malignant melanoma in the United States: issues as we approach the 21st century. J Am Acad Dermatol. May 1996;34(5 Pt 1):839-47. [Medline].

  6. Holman CD, Mulroney CD, Armstrong BK. Epidemiology of pre-invasive and invasive malignant melanoma in Western Australia. Int J Cancer. Mar 15 1980;25(3):317-23. [Medline].

  7. Goldstein AM, Dracopoli NC, Engelstein M, et al. Linkage of cutaneous malignant melanoma/dysplastic nevi to chromosome 9p, and evidence for genetic heterogeneity. Am J Hum Genet. Mar 1994;54(3):489-96. [Medline].

  8. Holman CD, Armstrong BK. Cutaneous malignant melanoma and indicators of total accumulated exposure to the sun: an analysis separating histogenetic types. J Natl Cancer Inst. Jul 1984;73(1):75-82. [Medline].

  9. Weinstock MA, Sober AJ. The risk of progression of lentigo maligna to lentigo maligna melanoma. Br J Dermatol. Mar 1987;116(3):303-10. [Medline].

  10. Buettiker UV, Yawalkar NY, Braathen LR, et al. Imiquimod treatment of lentigo maligna: an open-label study of 34 primary lesions in 32 patients. Arch Dermatol. Jul 2008;144(7):943-5. [Medline].

  11. NCCN practice guidelines in oncology for melanoma. v.2.2006.

  12. Agarwal-Antal N, Bowen GM, Gerwels JW. Histologic evaluation of lentigo maligna with permanent sections: implications regarding current guidelines. J Am Acad Dermatol. Nov 2002;47(5):743-8. [Medline].

  13. Stevenson O, Ahmed I. Lentigo maligna : prognosis and treatment options. Am J Clin Dermatol. 2005;6(3):151-64. [Medline].

  14. McKenna JK, Florell SR, Goldman GD, et al. Lentigo maligna/lentigo maligna melanoma: current state of diagnosis and treatment. Dermatol Surg. Apr 2006;32(4):493-504. [Medline].

  15. Bub JL, Berg D, Slee A, et al. Management of lentigo maligna and lentigo maligna melanoma with staged excision: a 5-year follow-up. Arch Dermatol. May 2004;140(5):552-8. [Medline].

  16. Gross EA, Andersen WK, Rogers GS. Mohs micrographic excision of lentigo maligna using Mel-5 for margin control. Arch Dermatol. Jan 1999;135(1):15-7. [Medline].

  17. Clark GS, Pappas-Politis EC, Cherpelis BS, et al. Surgical management of melanoma in situ on chronically sun-damaged skin. Cancer Control. Jul 2008;15(3):216-24. [Medline].

  18. Hazan C, Dusza SW, Delgado R, et al. Staged excision for lentigo maligna and lentigo maligna melanoma: A retrospective analysis of 117 cases. J Am Acad Dermatol. Jan 2008;58(1):142-8. [Medline].

  19. Abeldano AM, Saadi ME, Brea P. Amelanotic lentigo maligna melanoma. Skinmed. Jan-Feb 2004;3(1):41-4. [Medline].

  20. Albert VA, Koh HK, Geller AC. Years of potential life lost: another indicator of the impact of cutaneous malignant melanoma on society. J Am Acad Dermatol. Aug 1990;23(2 Pt 1):308-10. [Medline].

  21. Bastian BC. Understanding the progression of melanocytic neoplasia using genomic analysis: from fields to cancer. Oncogene. May 19 2003;22(20):3081-6. [Medline].

  22. Cohen LM. Lentigo maligna and lentigo maligna melanoma. J Am Acad Dermatol. Dec 1995;33(6):923-36; quiz 937-40. [Medline].

  23. Koh HK, Michalik E, Sober AJ, et al. Lentigo maligna melanoma has no better prognosis than other types of melanoma. J Clin Oncol. Sep 1984;2(9):994-1001. [Medline].

  24. Lachiewicz AM, Berwick M, Wiggins CL, et al. Survival differences between patients with scalp or neck melanoma and those with melanoma of other sites in the Surveillance, Epidemiology, and End Results (SEER) program. Arch Dermatol. Apr 2008;144(4):515-21. [Medline].

  25. Langford FP, Fisher SR, Molter DW. Lentigo maligna melanoma of the head and neck. Laryngoscope. May 1993;103(5):520-4. [Medline].

  26. Schiffner R, Schiffner-Rohe J, Vogt T, et al. Improvement of early recognition of lentigo maligna using dermatoscopy. J Am Acad Dermatol. Jan 2000;42(1 Pt 1):25-32. [Medline].

  27. Su LD, Fullen DR, Lowe L. Desmoplastic and neurotropic melanoma. Cancer. Feb 1 2004;100(3):598-604. [Medline].

  28. Whiteman DC, Stickley M, Watt P, et al. Anatomic site, sun exposure, and risk of cutaneous melanoma. J Clin Oncol. Jul 1 2006;24(19):3172-7. [Medline].

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Further Reading

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Keywords

skin cancer, skin cancer diagnosis, skin cancer treatment, skin cancer symptoms, malignant melanoma, skin malignancy, cutaneous malignancy, cutaneous melanoma, skin melanoma, cutaneous neoplasm, skin neoplasm, Hutchinson's melanotic freckle, Hutchinson melanotic freckle, freckle cancer, lentigo maligna, LM, lentigo maligna melanoma, LMM, melanoma in-situ, UV light exposure, ultraviolet light exposure, UV radiation exposure, ultraviolet radiation exposure, melanocytic nevus, melanocytic nevi

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Contributor Information and Disclosures

Author

Winston W Tan, MD, Assistant Professor of Medicine, Mayo Medical School; Consulting Staff, Mayo Group Practices
Winston W Tan, MD is a member of the following medical societies: American College of Physicians, American Society of Clinical Oncology, American Society of Hematology, Philippine Medical Association, and Texas Medical Association
Disclosure: Roche Grant/research funds Other; Sanofi Aventis Grant/research funds Other; Genentech Grant/research funds Other; Bristol Myers Squibb Grant/research funds Other

Coauthor(s)

Antony J Charles, MD, Fellow, Department of Hematology and Oncology, Mayo Clinic, St Luke's Hospital
Antony J Charles, MD is a member of the following medical societies: American Society of Clinical Oncology
Disclosure: Nothing to disclose.

Broc L Pratt, MD, Consulting Staff, Metrolina Plastic Surgery, Charlotte, North Carolina
Disclosure: Nothing to disclose.

B Todd Heniford, MD, Assistant Clinical Professor, Department of General Surgery, University of North Carolina; Chief, Division of Minimal Access Surgery, Carolinas Medical Center
B Todd Heniford, MD is a member of the following medical societies: Alpha Omega Alpha, American College of Surgeons, American Medical Association, American Society for Gastrointestinal Endoscopy, Association for Academic Surgery, and Society for Surgery of the Alimentary Tract
Disclosure: Nothing to disclose.

Medical Editor

Michael Perry, MD, MS, MACP, Nellie B Smith Chair of Oncology Emeritus, Professor, Department of Internal Medicine, Division of Hematology and Oncology, University of Missouri /Ellis Fischel Cancer Center
Michael Perry, MD, MS, MACP is a member of the following medical societies: Alpha Omega Alpha, American Association for Cancer Research, American College of Physicians, American College of Physicians-American Society of Internal Medicine, American Medical Association, American Society of Clinical Oncology, American Society of Hematology, International Association for the Study of Lung Cancer, and Missouri State Medical Association
Disclosure: Bionumerik Consulting fee Consulting; Proactya Consulting fee Consulting; GSK Consulting fee Consulting; NovoNordisk Consulting fee Consulting; Amgen Honoraria Speaking and teaching; GSK Consulting fee Speaking and teaching

Pharmacy Editor

Francisco Talavera, PharmD, PhD, Senior Pharmacy Editor, eMedicine
Disclosure: Nothing to disclose.

CME Editor

Rajalaxmi McKenna, MD, FACP, Consulting Staff, Department of Medicine, Southwest Medical Consultants, SC, Good Samaritan Hospital, Advocate Health Systems
Rajalaxmi McKenna, MD, FACP is a member of the following medical societies: American Society of Clinical Oncology, American Society of Hematology, and International Society on Thrombosis and Haemostasis
Disclosure: Nothing to disclose.

Chief Editor

Jules E Harris, MD, Clinical Professor of Medicine, Division of Hematology/Medical Oncology, Department of Internal Medicine, University of Arizona College of Medicine at Tucson; Consulting Staff, Arizona Cancer Center
Jules E Harris, MD is a member of the following medical societies: American Association for Cancer Research, American Association for the Advancement of Science, American Association of Immunologists, American Society of Hematology, and Central Society for Clinical Research
Disclosure: GlobeImmune Salary Consulting; Amplimed Consulting fee Consulting

 
 
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