Some autoimmune disorders like rheumatoid arthritis and psoriasis are indeed associated with an increased risk of cancer. The link between psoriasis and cancer was considered relatively recently.

A Danish systemic review, Prevalence, Incidence, and Risk of Cancer in Patients With Psoriasis and Psoriatic Arthritis: A Systematic Review and Meta-analysis (Vaengebjerg et al) made these observations about psoriasis:

> From a total of 112 studies included in the analysis, overall cancer prevalence among persons with psoriasis was 4.78% (95% CI, 4.02%-5.59%). When keratinocyte cancer was excluded from the analysis, the prevalence of overall cancer decreased to 4.06% (95% CI, 3.31%-4.87%). > > From the 14 studies that reported risk estimates in the context of overall cancer or included a reference group, the risk ratio for cancer development in those with psoriasis was 1.21 (95% CI, 1.11-1.33), but decreased to 1.14 (95% CI, 1.04-1.25) when keratinocyte cancer was excluded.

Here is an article summarizing the findings. Lymphomas and skin cancers are among the top cancers seen in among psoriasis patients.

A challenge with these studies is that they often look at people with severe manifestations of the disease, or that are being treated with immunosuppressive drugs such as biologics. The above study tries to account for the latter, but not (if I remember correctly) the former. While I don't have a citation in front of me, the association is mostly with severe psoriasis, not mild psoriasis.

Rheumatoid arthritis is another autoimmune disease tied to cancer. RA patients have double the risk of developing [lymphomas] https://www.arthritis.org/health-wellness/about-arthritis/related-conditions/other-diseases/arthritis-and-cancer-risk in particular.