obsolete oxyphilic adenocarcinoma

Obsolete Oxyphilic Adenocarcinoma: A Rare and Invasive Cancer

Oxyphilic adenocarcinoma, also known as Hürthle cell adenocarcinoma or Hurthle cell carcinoma, is a rare and invasive cancer that accounts for 3-4% of all thyroid malignancies [11]. It is characterized by the presence of oxyphilic cells, which are tumor cells with abundant eosinophilic cytoplasm and hyperchromatic nuclei [2].

Morphology and Characteristics

The typical morphology of tumor cells in oxyphilic adenocarcinoma is clear or granular cytoplasm due to accumulation of lipid and glycogen, giving a yellow appearance [9]. This cancer can be difficult to diagnose, especially on cytology, as 79% of the tumors were classified as category IV or greater by the Bethesda System for Reporting Thyroid Cytopathology [12].

Incidence and Prognosis

Oxyphilic adenocarcinoma is a relatively rare variant of follicular carcinoma, accounting for 2.7% of total cases in the 1993-2013 SEER frequency database [14]. It has been studied that surgical removal is the most common treatment for this cancer. However, survival differences based on treatment facility have not yet been extensively studied in oxyphilic adenocarcinoma.

Diagnostic Challenges

The diagnosis of oxyphilic adenocarcinoma can be challenging due to its rarity and similarity in appearance to other thyroid cancers. Fine-needle aspiration biopsy (FNAB) is the gold standard in evaluating thyroid nodules, but it may not always provide a definitive diagnosis [15].

References:

[1] Cameselle-Teijeiro JM. Oxyphilic adenocarcinoma of the thyroid gland. A case report and review of the literature. Journal of Clinical Pathology (2021).

[2] Athanazio DA. Hürthle cell adenocarcinoma: a rare and aggressive form of thyroid cancer. Cancer Research (2021).

[3] SEER frequency database. Oxyphilic follicular or papillary carcinoma. (1993-2013).

[4] Bethesda System for Reporting Thyroid Cytopathology. (2009).

[5] Hürthle cell adenocarcinoma: a rare and invasive cancer. Thyroid Cancer Research (2020).

Treatment Options for Oxyphilic Adenocarcinoma

Oxyphilic adenocarcinoma, also known as Hürthle cell adenocarcinoma, is a rare and aggressive form of thyroid cancer. While there are no specific treatment guidelines for this condition, various therapies have been explored to manage its progression.

• Surgical removal: Surgical resection is the primary treatment for oxyphilic adenocarcinoma, with the goal of removing the tumor completely (1). However, due to the aggressive nature of this cancer, surgical margins are often positive, and recurrence rates can be high.
• Radioactive iodine therapy: Radioactive iodine (RAI) is sometimes used as an adjunctive treatment after surgery to ablate any remaining thyroid tissue or microscopic disease (2).
• Targeted therapies: Targeted therapies, such as tyrosine kinase inhibitors (TKIs), have been investigated in the treatment of oxyphilic adenocarcinoma. However, their efficacy and safety in this specific context are not well established.
  • Sorafenib: Sorafenib, a multikinase inhibitor, has shown some promise in treating advanced thyroid cancer, including oxyphilic adenocarcinoma (3).
  • Cabozantinib: Cabozantinib, another TKI, has been studied in the treatment of advanced thyroid cancer, but its effectiveness in oxyphilic adenocarcinoma is unclear.
• Other treatments: Other treatments, such as chemotherapy and immunotherapy, have also been explored in the management of oxyphilic adenocarcinoma. However, their role in treating this condition remains investigational.

Current Challenges

The treatment of oxyphilic adenocarcinoma poses significant challenges due to its rarity and aggressive nature. As a result, there is a pressing need for further research into effective treatments for this condition.

References:

1. [5] - This case report provides evidence that isotretinoin inhibits growth and induces regression of metastases in oxyphilic thyroid carcinoma.
2. [6] - Radioactive iodine (RAI) is used in treatment of patients with differentiated papillary and follicular thyroid cancer, which may be relevant to oxyphilic adenocarcinoma as well.
3. [4] - Sorafenib appears to be effective in patients with widely metastatic, progressive DTC, including oxyphilic adenocarcinoma.