Transverse Melanonychia as A Rare Paraneoplastic Manifestation of Pancreatic Adenocarcinoma: A Case Report
Dr. Rishabh Gupta *1, Dr. Vidhi Agarwal 2, Dr. Maneesh Vijayavargiya 3
*Correspondence to: Dr. Rishabh Gupta, Department of Gastroenterology, Gupta Multispeciality hospital, Jaipur.
Copyright
© 2026 Dr. Rishabh Gupta, This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Received: 29 July 2026
Published: 11 August 2026
DOI: https://doi.org/10.5281/zenodo.21887347
Abstract
Transverse melanonychia is a rare nail pigmentation pattern and is usually related to benign conditions or systemic disorders. We report a 49-year-old male with pancreatic adenocarcinoma who presented with transverse hyperpigmented bands on multiple nails. Imaging and FNAC confirmed metastatic pancreatic cancer, and nail biopsy showed increased melanocytes with melanin deposition. No alternative etiologies for melanonychia were identified. To our knowledge, this is the first reported case of transverse melanonychia associated with carcinoma pancreas. This case underscores the importance of recognizing unusual nail changes as potential clues to internal malignancy.
Introduction
Melanonychia refers to black or brown discolouration of finger or toenail plate, commonly in darker skin tones [1,2]. Nail pigmentation is usually in the form of longitudinal pigmented bands and may be associated with pigmentation of lips and oral mucosa termed as Laugier Hunziker syndrome [1,3].
Total or Transverse melanonychia is rare. It is most commonly due to benign etiologies due to melanocytic activation, hyperplasia or melanin producing pathogens and rarely due to melanoma.
We present a rare case of transverse Melanonychia occurring in association with carcinoma pancreas with no other identifiable etiology and no family history of such lesions.
Case Report
A 49-year-old male presented with progressive Jaundice, epigastric pain, dark coloured urine, clay coloured stools, generalised pruritus, loss of appetite and weight loss for 4 months. He also reported brown - black discolouration of fingernails and toenails.
Past medical history, drug history and family history were unremarkable. On examination, patient was icteric and emaciated, with no palpable superficial lymph nodes. Multiple black transverse hyperpigmented bands were noted on most fingernails and toenails (FIGURE 1).
On Systemic examination, liver was firm and gallbladder was cystic in nature. CBC revealed a Hb of 10.7 gm/dL, WBC 10,100/cmm and platelets 244,000/cmm. ESR was 25 mm/hr. LFT showed total and direct bilirubin of 14.1 and 8.2 mg/dl respectively (reference range 0-1), ALT 92 IU/L (5 - 40), AST 54 U/L (5 - 40), alkaline phosphatase 839 IU/L (25 - 140), GGT 201 IU/L (1-94), total protein 5.2 gm/dl (6.2-8.5), albumin 2.5 gm/dl (3.4-5.0). Amylase 164 U/L (upto 90 U/L), Lipase 177 U/L (upto 90 U/ L). Renal function tests, PT/INR, PTT, thyroid function tests were normal. Serology were negative for HBsAg, HCV-Ab and HIV I/II. Chest and abdominal X-ray were normal.
Abdominal ultrasound revealed a poor echogenic irregular mass of 4*3 cm at the region of pancreatic head with multiple enlarged lymph nodes in peri-pancreatic region, dilated common bile duct upto 18 mm and Intrahepatic biliary radicles dilatation.
Contrast enhanced computed tomography (CT) abdomen revealed a heterogenously enhancing soft tissue lesion with internal areas of necrosis of 42*37 mm in pancreatic head which was hypoenhancing in arterial and portal phase with no contrast washout in venous phase. It was encasing the lower common bile duct with resultant dilatation of proximal CBD, CHD and intrahepatic biliary radicles. Few heterogenous lymph nodes were noted in para-gastric and peri-pancreatic regions. Few small heterogenously enhancing lesions were noted in right lobe of liver likely metastatic (FIGURE 2). CA 19-9 was > 1000 U/mL.
FNAC of Pancreatic and Liver lesions revealed moderately differentiated pancreatic adenocarcinoma with metastatic lesions in liver. Due to unresectable disease, Endoscopic Palliative drainage was performed. Endoscopic retrograde cholangiopancreatography (ERCP) was done and one 10 French double pigtail stent was placed.
Why this Case is Unique
To the best of our knowledge, transverse melanonychia has never been reported as a cutaneous or paraneoplastic manifestation of pancreatic adenocarcinoma.
This case highlights an unusual nail finding that may serve as a potential clinical clue for internal malignancy, especially when accompanied by systemic symptoms.
Discussion
Melanonychia results due to increased melanin pigment deposition in the nail plates and nail matrix epithelium with or without concurrent increase in number of melanocytes [1-4]. It is a diagnostic challenge for clinicians. Various causes are responsible for this condition and mostly are benign. Apart from dermatological conditions, it can be associated with systemic diseases, drugs etc. as illustrated in TABLE 1. (5)
Nail changes provide an important clue for the diagnosis of various inflammatory & systemic conditions and syndromes and can be an initial Red Flag sign of Internal malignancies. TABLE 2 illustrates various nail changes associated with internal malignancies and systemic diseases [6,9]. TABLE 3 illustrates various cutaneous manifestations of Internal malignancies.
So, a detailed history and physical examination is mandatory in all patients with nail and cutaneous manifestations. An algorithmic approach is the key to avoid misdiagnosis and delay in diagnosis.
Carcinoma pancreas can rarely present as cutaneous metastasis but, its association with melanonychia has never been reported so far [7,8].
For the diagnosis of Melanonychia, dermoscopy and biopsy of nail plate is helpful. Regarding management of melanonychia, there is no effective treatment available till now. Some nail changes may reverse with the underlying disease treatment.
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TABLE 3 : Cutaneous manifestations of Internal malignancies |
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Conclusion
This case emphasises the importance of recognising nail changes, such as melanonychia, as potential indicators of internal malignancy. Clinicians must acquaint themselves with the association of melanonychia and other nail and cutaneous manifestations with systemic diseases, drugs and Internal malignancies apart from dermatological causes to allow for early diagnosis and prevent misdiagnosis. Further studies are needed to explore whether melanonychia may serve as a paraneoplastic marker in pancreatic carcinoma.
Consent:
Written informed consent was obtained from the patient for publication of this case and accompanying images.
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