Paraneoplastic Acrokeratosis (Bazex Syndrome) associated with pulmonary adenocarcinoma

 Corresponding author: Lemyaa Es-solh Marhraoui. Copyright © 2025 Author(s) retain the copyright of this article. This article is published under the terms of the Creative Commons Attribution License 4.0. Paraneoplastic Acrokeratosis (Bazex Syndrome) associated with pulmonary adenocarcinoma Lemyaa Es-solh Marhraoui *, Fouzia Hali and Soumiya Chiheb Department of Dermatology and Venereology, Faculty of Medicine and Pharmacy, University of Hassan II Casablanca, IBN ROCHD University Hospital of Casablanca, Morocco. World Journal of Advanced Research and Reviews, 2025, 26(02), 3367-3369 Publication history: Received on 07 April 2025; revised on 19 May 2025; accepted on 21 May 2025 Article DOI: https://doi.org/10.30574/wjarr.2025.26.2.1946 Abstract Bazex paraneoplastic acrokeratosis is a rare dermatosis often preceding the diagnosis of internal malignancies, most commonly squamous cell carcinoma of the upper aerodigestive tract. We report the case of an 82-year-old man with pulmonary adenocarcinoma presenting with erythematous and scaly plaques with palmoplantar keratosis. Clinical and histologic findings supported the diagnosis of Bazex syndrome. This case emphasizes the importance of recognizing paraneoplastic skin signs as potential early indicators of hidden cancers. Keywords: Bazex Syndrome; Paraneoplastic Acrokeratosis; Pulmonary Adenocarcinoma; Paraneoplastic dermatosis; Acrokeratosis Paraneoplastica 1. Introduction Bazex paraneoplastic acrokeratosis is a rare paraneoplastic dermatosis characterized by symmetrical, erythematous to violaceous, scaly plaques that typically affect acral areas such as the hands, feet, ears, and nose. It is associated with underlying malignancies, particularly squamous cell carcinomas of the upper aerodigestive tract, although cases involving lung, gastrointestinal, and genitourinary tumors have also been reported. Since the cutaneous manifestations often precede the diagnosis of the underlying cancer in more than two-thirds of cases, early recognition of Bazex syndrome is essential. Prompt identification may facilitate earlier detection and management of an otherwise occult malignancy, potentially improving patient outcomes. 2. Case Report An 82-year-old male patient, a chronic smoker, was recently diagnosed with poorly differentiated and invasive pulmonary adenocarcinoma with adrenal metastases. He is currently undergoing palliative chemotherapy. Over the past six weeks, he developed pruritic, erythematous lesions in the axillary, inguinal, and intergluteal folds, which were treated empirically with antifungal agents without clinical improvement. On examination, erythematous, slightly infiltrated lesions with overlying scales were observed in the inguinal, axillary (figure 1), and intergluteal folds, as well as on the face and neck. These lesions were accompanied by palmoplantar keratosis (figure 2) and diffuse xerosis. World Journal of Advanced Research and Reviews, 2025, 26(02), 3367-3369 3368 Figure 1 Well-defined erythematous-squamous lesions localized in the axillary area Figure 2 Bilateral palmar keratosis A skin biopsy was performed, which, although non-specific, helped rule out other differential diagnoses such as psoriasis, eczema, seborrheic dermatitis, and cutaneous fungal infections. The patient was subsequently started on topical corticosteroids and phototherapy sessions. 3. Discussion Paraneoplastic acrokeratosis, also known as Bazex syndrome, is a rare cutaneous paraneoplastic manifestation first described by André Bazex in 1965. It remains a diagnostic challenge due to its rarity and its clinical overlap with more common dermatoses. While it is typically associated with squamous cell carcinomas of the upper aerodigestive tract [1], it can also be observed in association with other malignancies, such as pulmonary carcinoma, as reported in a few case series [2, 3, 4] and as demonstrated in our case. Clinical signs most often appear before the initial symptoms of the underlying neoplasm. They typically present as poorly defined, red to violaceous, scaly plaques located on the ears, nose, hands, and feet. Palmoplantar keratosis is frequently observed and may be one of the earliest signs. Knee involvement is reported in less than 25% of cases and usually occurs at a later stage. Nail changes are characterized by subungual hyperkeratosis and onycholysis [1, 3]. The pathogenesis is still unclear, several mechanisms have been proposed. One leading theory suggests that tumorsecreted growth factors, such as epidermal growth factor or transforming growth factor-alpha, may lead to epidermal proliferation and hyperkeratosis. Alternatively, autoimmune responses triggered by tumor antigens might result in cutaneous inflammation through molecular mimicry or epitope spreading [5]. Management of Bazex syndrome relies predominantly on treating the underlying neoplasm. In some cases, dermatologic symptoms regress entirely with tumor remission, highlighting the paraneoplastic nature of the condition. However, when curative treatment is not feasible, as in this case due to metastatic disease, symptomatic therapies such as Steroids, World Journal of Advanced Research and Reviews, 2025, 26(02), 3367-3369 3369 both topical and systemic, Oral retinoids, PUVA therapy may offer partial relief. In addition, other topical ointments reported include zinc ointment, emollients, salicylic acid, keratolytics, itraconazole, fluconazole, vitamin D analogues, and antibiotics [6]. This case underscores the importance of considering Bazex syndrome in the differential diagnosis of recalcitrant erythematous and scaly eruptions, particularly in elderly patients with a known or suspected malignancy. Early dermatologic referral and skin biopsy can contribute to prompt recognition and may even facilitate earlier detection of hidden tumors, potentially improving prognosis. 4. Conclusion Bazex paraneoplastic acrokeratosis, though rare, serves as a valuable clinical clue for underlying malignancy. Dermatologists and oncologists should maintain a high index of suspicion when encountering treatment-resistant erythematous and scaly lesions, especially in elderly or high-risk individuals. This case underscores the need for interdisciplinary collaboration to ensure timely diagnosis and management of associated cancers. Compliance with ethical standards Disclosure of conflict of interest The authors declared no potential conflicts of interest. Statement of informed consent The patient in this manuscript has given written informed consent to the publication of the case details and clinical images. References [1] Pulickal JK, Kaliyadan F. Acrokeratosis Paraneoplastica. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2025 Jan– [updated 2023 May 22]. [2] Amano M, Hanafusa T, Chikazawa S, et al. Bazex syndrome in lung squamous cell carcinoma: high expression of epidermal growth factor receptor in lesional keratinocytes with Th2 immune shift. Case Rep Dermatol. 2016;8:358–362. [3] Mititelu R, Powell M. A case report of resolution of acrokeratosis paraneoplastica (Bazex syndrome) post resection of non-small-cell lung carcinoma. SAGE Open Med Case Rep. 2019;7:2050313X19860164. [4] Aoshima Y, Karayama M, Sagisaka S, et al. Synchronous occurrence of Bazex syndrome and remitting seronegative symmetrical synovitis with pitting edema syndrome in a patient with lung cancer. Intern Med. 2019;58:3267–3271. 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