A fifth of cancer patients at the Wye Valley Trust said they did not receive the right support from their GP practice during their care, new figures show.
Macmillan Cancer Support said everyone diagnosed with cancer "should be receiving support that's right for their needs".
Figures from NHS England's cancer patient experience survey showed 21% of 154 patients who said the support they received from their GP during their cancer care at Wye Valley NHS Trust last year was not right.
Across England, the proportion of patients who said the support from their GP was not good enough was 22%.
The figures also showed the average rating of the 214 people who received cancer care at the Wye Valley Trust and provided an overall score was 8.9 out of 10.
Nationally, the overall experience of cancer patients rose marginally to 8.9 out of 10 last year.
Meanwhile, transgender cancer patients endured worse experiences than cisgender patients, providing an average score of 8.3 compared with 8.9.
Black patients also said they suffered from poorer experiences than white people, while gay and lesbian, and bisexual patients also scored their care lower.
Sarah Ruane, director of advocacy at Macmillan Cancer Support said: "It’s unacceptable that some people from ethnically diverse backgrounds, the LGBTQ+ community, or with an additional long-term health condition are significantly more likely to report poorer overall experiences of cancer care.
"But it doesn’t have to be this way. Everyone diagnosed with cancer across the UK should be receiving support that’s right for their needs."
Meanwhile, 75 out of 89 patients said they had confidence and trust in every member of the team looking after them.
This was up slightly from 59 out of 80 the year before.
Cancer Research UK said people are waiting too long for a diagnosis and to begin treatment, despite the NHS treating more patients than ever before.
Director of evidence and implementation, Naser Turabi, said: "A dedicated long-term cancer strategy is desperately needed to bring cancer waiting times down in England.
"We urge the Government to deliver investment and reform across NHS cancer services to ensure all patients receive the level of care they deserve."
An NHS spokesperson said: "Patient experience of care is incredibly important to the NHS and this survey is vital in highlighting where we can improve services.
"It’s encouraging to see that, on average, patients rated their overall experience of care 8.89 out of ten compared to 8.88 last year – and that more than three quarters of those surveyed said they received the right amount of support from hospital staff.
"But we recognise that more work is needed to tackle the current challenges faced by cancer services and ensure all patients receive high-quality and timely care."