Increased risk of preneoplastic colonic lesions and colorectal carcinoma in acromegaly: multicenter case-control study

Incidence and risk factors of cancers in acromegaly: a Chinese single-center retrospective study

PURPOSE

To evaluate the incidence of malignancies in acromegaly and to identify risk factors for newly-diagnostic cancers, especially the excessive growth hormone (GH) and insulin-like growth factor-1 (IGF-1).

METHODS

A retrospective cohort including 1738 consecutive hospitalized patients with acromegaly in a single referral center between 2012 and 2020 (mean follow-up 4.3 years). A gender- and age-matched case-control study (280 patients from the cohort) was performed for risk factor analysis.

RESULTS

One hundred thirteen malignancies (67 diagnosed after acromegaly) were observed. The overall newly-diagnostic cancer risk of acromegaly was higher than the general population (standardized incidence ratio (SIR) 2.81; 95% CI 2.18-3.57). The risk of thyroid cancer (n = 33, SIR 21.42; 95% CI 13.74-30.08) and colorectal cancer (n = 8, SIR 3.17; 95% CI 1.37-6.25) was elevated. In the overall cohort, IGF-1 (ULN: 1.27 vs. 0.94, p = 0.057), GH (1.30 vs. 1.00 ng/ml, p = 0.12), and disease-controlled rate (34.9% vs. 45.9%, p = 0.203) at the last visit did not reach significance between patients with and without post-diagnostic cancer. In the case-control study, GH (1.80 vs. 0.90 ng/ml, p = 0.018) and IGF-1 (ULN: 1.27 vs. 0.91, p = 0.003) at the last visit were higher in patients with post-diagnostic cancers, with a lower disease-controlled rate. Elder age was a risk factor for cancer. Other metabolic comorbidities and the size of pituitary tumors were similar.

CONCLUSION

The risk of malignancies, especially thyroid cancer, was increased in patients with acromegaly in our center. More cancer screening should be considered when managing acromegaly, especially in patients with higher posttreatment GH and IGF-1.

Growth hormone and gastrointestinal malignancy: An intriguing link

Growth hormone (GH) excess is associated with several systemic complications, one of which is the increased risk of neoplastic processes particularly of the gastrointestinal (GI) tract. Among the GI neoplasms, the most reported association is with benign and malignant neoplasms of the colon. In the majority of published literature, an increased incidence of GI neoplasms, both colonic adenomas as well as colorectal carcinoma is reported. However, the studies on colon cancer-specific mortality rate are conflicting with recent studies reporting similar cancer-specific mortality rates in comparison to controls. Many studies have reported an association of colorectal neoplasms with GH levels. Pathogenic mechanisms put forward to explain this association of GH excess and GI neoplasms primarily involve the increased GH-insulin-like growth factor 1 (IGF-1) signaling. Both GH and IGF-1 have proliferative, anti-apoptotic, and angiogenic effects on the systemic tissues leading to cellular proliferation. Other contributing factors to the increased risk of GI neoplasms include slow intestinal transit with a redundant large bowel, altered bile acids, deranged local immune response, shared genetic susceptibility factors and hyperinsulinemia. In view of the increased risk association, most guidelines for the care of acromegaly patients recommend an initial screening colonoscopy. Recommendations for further follow-up colonoscopy differ but broadly, the guidelines agree that it depends on the findings at first colonoscopy and state of remission of GH excess. Regarding the concern about the risk of colorectal cancers in patients receiving recombinant GH therapy, most cohort studies do not show an increased risk.

Clinical Characteristics and Associated Factors of Colonic Polyps in Acromegaly

PURPOSE

To investigate the clinical characteristics and associated factors of colonic polyps in patients with acromegaly.

METHODS

Clinical characteristics and colonoscopy findings of 86 acromegaly patients who received treatment were retrospectively reviewed, and colonoscopy findings and the correlation with growth hormone (GH)-secreting pituitary adenoma (GHPA) volume and hormonal/metabolic levels were analyzed.

RESULTS

The prevalence of colonic polyps in acromegaly patients was 40.7% and increased significantly with advanced age, especially in those ≥50 years. Multiple polyps (62.8%) and colonic polyps in the left colon (54.2%) were detected more frequently. Compared to acromegaly patients without polyps, those with polyps displayed higher insulin-like growth factor-1 × upper limit of normal (IGF-1×ULN) levels (P=0.03). IGF-1 levels and GHPA volumes in patients with polyps showed increasing trends, although the differences were not significant. GH levels were higher in patients with polyps of diameter ≤5 mm than those with polyps of diameter >5 mm (P=0.031). The univariate and multivariate logistic regression analysis revealed that GHPA volumes (OR: 1.09, 95% CI: 1.01-1.20; P=0.039) and IGF-1×ULN Q2 levels (OR: 6.51, 95% CI: 1.20-44.60; P=0.038) were independent factors for predicting the risk of colonic polyp occurrence in acromegaly patients. A nomogram was prepared to evaluate the risk of colonic polyps in acromegaly patients.

CONCLUSION

The acromegalic patients are a population with a high prevalence of colonic polyps. GHPA volumes and IGF-1×ULN levels may be predictors of colonic polyp occurrence.

Cancer prevalence and cancer screening in patients with acromegaly: a single center experience

PURPOSE

To investigate the prevalence of cancer in patients with acromegaly and the variables associated with malignant and premalignant lesions detected by cancer screening.

METHODS

The data of 214 patients diagnosed with acromegaly in our institution were evaluated retrospectively. Prevalence of cancer was compared with national rates to estimate standardized incidence ratios (SIRs). The relationships of malignant and premalignant lesions detected by cancer screening with demographic, clinical, and radiological variables were also analyzed.

RESULTS

Cancer was detected in 24 (13.4%) of 179 patients enrolled in the study. Compared to the general population, the incidence of all malignancies was increased in both women and men with acromegaly (SIR: 4.78, 95% CI: 2.43-8.53, p = 0.002 and SIR: 8.97, 95% CI: 5.51-14.7, p < 0.001, respectively). The most common cancers were thyroid, colorectal, breast, kidney, gastric, and testicular cancer, respectively. Duration of disease was the only independent risk factor for the development of cancer (OR: 1.007, 95% CI: 1.002-1.011, p = 0.002). Malignant/premalignant lesions were detected in 21.5% of the patients with a colonoscopy scanning procedure and in 20.8% with an esophagogastroduodenoscopy procedure, and current age was found to be higher among the patients with malignant/premalignant lesions (p = 0.023 and p = 0.003, respectively). Breast cancer was detected in 3.7% of screening tests performed with mammography.

CONCLUSION

In this study, it was shown that the prevalence of cancer increases with acromegaly and this increase is associated with disease duration. Considering the increase in the number of premalignant lesions, the scope of cancer screening recommendations in the guidelines should be expanded to ensure early diagnosis.

Pituitary tumors and the risk of other malignancies: is the relationship coincidental or causal?

Pituitary adenomas are benign neoplasms of the pituitary. The most prevalent are prolactinomas and non-functioning pituitary adenomas, followed by growth hormone- and ACTH-secreting adenomas. Most pituitary adenomas seem to be sporadic and their persistent growth is very atypical. No molecular markers predict their behavior. The occurrence of pituitary adenomas and malignancies in the same patient can be either pure coincidence or caused by shared underlying genetic susceptibility involved in tumorigenesis. Detailed family history on cancers/tumors in the first, second and third generation of family members on each side of the family has been reported in a few studies. They found an association of pituitary tumors with positive family history for breast, lung and colorectal cancer. We have reported that in about 50% of patients with pituitary adenomas, an association with positive family history for cancer has been found independent of secretory phenotype (acromegaly, prolactinoma, Cushing's disease or non-functioning pituitary adenomas). We also found earlier onset of pituitary tumors (younger age at diagnosis of pituitary tumors) in patients with a strong family history of cancer. In our recent unpublished series of 1300 patients with pituitary adenomas, 6.8% of patients were diagnosed with malignancy. The latency period between the diagnosis of pituitary adenoma and cancer was variable, and in 33% of patients, it was longer than 5 years. Besides the inherited trophic mechanisms (shared underlying genetic variants), the potential influence of shared complex epigenetic influences (environmental and behavioral factors - obesity, smoking, alcohol intake and insulin resistance) is discussed. Further studies are needed to better understand if patients with pituitary adenomas are at increased risk for cancer.

Acromegaly and the Colon: Scoping Beyond the Pituitary

Acromegaly is a complex endocrinological disorder commonly caused by hypersecretion of growth hormone (GH) typically due to pituitary gland tumors. Patients with acromegaly who are successfully treated and biochemically managed have a reasonably average life expectancy. However, it causes a cascade of multi-systemic involvement throughout the patient's life, including cardiovascular, neuropsychiatric, respiratory, metabolic, neurological, neoplastic, and gastrointestinal involvement, resulting in a higher rate of hospitalization, lower quality of life, and a shorter life expectancy. Although cardiovascular complications are the primary cause of death in patients with acromegaly, malignancy is now emerging as a major killer in these individuals. Colorectal carcinoma has been reported to be prevalent in acromegaly individuals. This review article has compiled studies to demonstrate a link between acromegaly and colorectal neoplasia, intending to provide a strong foundation for their clinical relationship. This article has summarised a potential pathogenic mechanism and provided insights into the clinical presentation of such patients. Furthermore, this article has provided a brief overview of current screening recommendations for colorectal neoplasia in acromegaly patients.

Acromegaly: achieving timely diagnosis and improving outcomes by personalized care

PURPOSE OF REVIEW

Discuss recent literature regarding clinical manifestations and comorbidities in acromegaly, with focus on early diagnosis and customized care.

RECENT FINDINGS

The mean interval between onset of clinical manifestations and diagnosis is currently 3-5 years. Women, especially younger than 50 years of age, experience longer delays, have lower insulin-like growth factor 1 (IGF-1) levels and larger tumors than men. Development of comorbidities usually precedes the diagnosis and is influenced by age, sex, and biochemical disease activity. Comorbidities other than irreversible osteoarticular structural changes usually improve after acromegaly treatment. In patients with diabetes, the course of hyperglycemia not only depends on biochemical control but also on specific acromegaly therapies. Quality of life is influenced by sex, as well as by acromegaly symptoms, biochemical activity, and treatment. Quality of life remains lower than general population despite biochemical remission.

SUMMARY

Early diagnosis can be achieved by suspecting acromegaly based on suggestive clinical scenarios rather than obvious changes in appearance. Personalized care entails a proactive multidisciplinary approach to identify and treat comorbidities while carefully monitoring the effects of acromegaly treatment.

Insulin-Like Growth Factor 1 (IGF-1) Signaling in Glucose Metabolism in Colorectal Cancer

Colorectal cancer (CRC) is one of the most common aggressive carcinoma types worldwide, characterized by unfavorable curative effect and poor prognosis. Epidemiological data re-vealed that CRC risk is increased in patients with metabolic syndrome (MetS) and its serum components (e.g., hyperglycemia). High glycemic index diets, which chronically raise post-prandial blood glucose, may at least in part increase colon cancer risk via the insulin/insulin-like growth factor 1 (IGF-1) signaling pathway. However, the underlying mechanisms linking IGF-1 and MetS are still poorly understood. Hyperactivated glucose uptake and aerobic glycolysis (the Warburg effect) are considered as a one of six hallmarks of cancer, including CRC. However, the role of insulin/IGF-1 signaling during the acquisition of the Warburg metabolic phenotypes by CRC cells is still poorly understood. It most likely results from the interaction of multiple processes, directly or indirectly regulated by IGF-1, such as activation of PI3K/Akt/mTORC, and Raf/MAPK signaling pathways, activation of glucose transporters (e.g., GLUT1), activation of key glycolytic enzymes (e.g., LDHA, LDH5, HK II, and PFKFB3), aberrant expression of the oncogenes (e.g., MYC, and KRAS) and/or overexpression of signaling proteins (e.g., HIF-1, TGF-β1, PI3K, ERK, Akt, and mTOR). This review describes the role of IGF-1 in glucose metabolism in physiology and colorectal carcinogenesis, including the role of the insulin/IGF system in the Warburg effect. Furthermore, current therapeutic strategies aimed at repairing impaired glucose metabolism in CRC are indicated.